JP2007208140A - Coating method, coating apparatus and coating treatment program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a control of a film thickness when employing a suck back method in a spinless coating using a longer nozzle, and to elevate a quality of a coat. <P>SOLUTION: In the end of coat scanning, a discharge rate of treatment liquid of a nozzle is increased for a moment, whereby, a heaped-up portion of a coating film on a substrate is formed at the predetermined position on the substrate, preferably, near a boundary between a film-thickness guaranteed area and its unguaranteed area. Then, the nozzle is allowed to carry out the suction of the treatment liquid, i.e. suck back, at the scanning ending position on the substrate just after the scanning ending to remove an extra treatment liquid on the coating scanning ending portion. At that time, the effect of suck back (suction action) is canceled on the heaped-up treatment liquid portion, thereby preventing the film thickness in the film thickness guaranteed area from being lower than a tolerance. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coating method, a coating apparatus, and a coating processing program for forming a coating film of a processing liquid on a substrate to be processed using a long nozzle.

  In a photolithography process in the manufacturing process of flat panel displays (FPD) such as LCD, a long resist nozzle having a slit-like discharge port is scanned to apply a resist solution onto a substrate to be processed (glass substrate or the like). A spinless coating method is often used.

In such a spinless coating method, for example, as disclosed in Patent Document 1, a substrate is placed horizontally on a mounting table or a stage, and a substrate on the stage and a discharge port of a long resist nozzle are formed. A minute gap of several hundred μm or less is set between them, and the resist nozzle is moved in the scanning direction (generally in the horizontal direction perpendicular to the longitudinal direction of the nozzle) above the substrate, and the resist solution is discharged onto the substrate in a band shape and applied. By simply moving the long resist nozzle once from one end to the other end of the substrate, the resist coating film can be formed on the substrate with a desired film thickness without dropping the resist solution outside the substrate.
JP-A-10-156255

  In the conventional spinless coating method, there is room for improvement in the control of the film thickness of the resist coating film, and in-plane uniformity is particularly a problem. Specifically, the resist solution in the resist nozzle is connected to the resist solution film on the substrate only by stopping the pump of the resist solution supply source at the end of the coating scan and withdrawing the resist nozzle as it is outside or above the substrate. Since the liquid is drained after being discharged, there is a problem that the resist coating film tends to rise at the rear end portion of the substrate in the coating scanning direction.

  Generally, a margin area having a predetermined width is set at the peripheral edge of the upper surface (surface to be processed) of the substrate, and a device is formed in a product area inside the margin area. Therefore, in the resist coating process, if the product area is a guaranteed area where the film thickness of the resist coating film must be guaranteed, and the film thickness of the resist coating film is within a predetermined allowable range throughout the guaranteed area. In general, even if a bulge exceeding the allowable range occurs in the peripheral margin region, the film thickness profile of the resist coating film does not become defective.

  However, since the peripheral resist applied to the margin area may cause particles, it is removed in a subsequent process using a peripheral exposure machine or the like. However, if the resist film thickness is large, it may not be able to be removed completely. In this respect, the swell of the resist coating film at the coating scanning end portion becomes a problem.

  In order to suppress the swell of the resist coating film at the coating scanning end portion, the coating scanning end position is set on the substrate, the resist nozzle is temporarily stopped there, and the resist solution is stopped or stopped at rest. A so-called suck back method has been conventionally performed in which a resist solution is sucked from a substrate by reversing a pump of a supply source.

  However, when the suck-back method is used under the conventional technology, the thinning of the resist coating film by absorbing the resist solution through the resist nozzle does not stop within the margin area, but extends to the film thickness guarantee area. There was a possibility that the resist film thickness of the inside would fall below a set value or an allowable range.

  In addition, the air in the atmosphere (air) is sucked into the resist nozzle together with the resist solution on the substrate during suck back, and this is the basis for the single wafer continuous coating process. There is also a problem that the resist film thickness at the coating scanning start portion is remarkably lowered as the number of treatments is increased. That is, the long resist nozzle has a buffer chamber for temporarily buffering or storing the resist solution sent from the resist solution supply source in the nozzle in order to equalize the discharge pressure at the slit-like discharge port. A slit-like discharge passage having the same gap size as the discharge port is provided from the cavity to the discharge port. As described above, air sucked into the discharge port of the resist nozzle together with the resist solution on the substrate at the time of suck back enters the inner cavity through the discharge passage, and then diffuses and diffuses in the room. Mix in resist solution. If the number of continuous coating treatments, that is, the number of suckbacks, is increased, the amount of air mixing also increases. When the resist solution supply source pump is started at the start of the application scan, the discharge pressure from the pump decreases due to the mixed air in the cavity (air engagement occurs), and thereby the rise until the set pressure is reached. As a result, the resist coating film at the coating scanning start portion becomes thin.

  The present invention has been made in view of such problems of the prior art, and improves film thickness controllability when using a suck back method in a spinless coating method using a long nozzle and improves coating quality. An object is to provide a coating method, a coating apparatus, and a coating processing program.

  In order to achieve the above object, in the first coating method of the present invention, the substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a minute gap therebetween, and A coating method for forming a coating film of the processing liquid on the substrate by performing coating scanning in which the nozzle is moved in a relatively horizontal direction while discharging the processing liquid from the nozzle, wherein the nozzle is formed on the substrate. And setting a scanning end point position for relatively stopping the nozzle, and at a final stage of the coating scan, a relative horizontal movement speed of the nozzle with respect to the substrate is substantially equal to zero from the first horizontal movement speed. 2 to reduce the horizontal movement speed to a position where the nozzle is at the scanning end position, and at the end of the coating scan, the gap between the substrate and the nozzle is made larger than the first distance interval. Small second In the process of decreasing to the separation interval and at the end of the coating scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate higher than the first discharge rate, and then the second Decreasing the discharge rate and stopping the supply of the processing liquid; and causing the nozzle at the scanning end position to suck a predetermined amount of the processing liquid on the substrate.

  A first coating apparatus according to the present invention includes a substrate support unit for supporting a substrate to be processed substantially horizontally and a long length for discharging a processing liquid across a small gap on the upper surface of the substrate during coating scanning. Shaped nozzle, a processing liquid supply source for pumping the processing liquid to the nozzle during application scanning, and a scanning unit for moving the nozzle relative to the substrate during application scanning And a lifting unit for moving the nozzle in a vertical direction relative to the substrate, and the scanning unit to control the horizontal movement of the nozzle relative to the substrate at the end of the coating scan. Is reduced from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero, the nozzle is positioned at the scanning end point position, and the elevating unit is controlled to control the application scanning. At the end, between the substrate and the nozzle The gap is decreased from the first distance interval to a second distance interval smaller than the first distance interval, and the treatment liquid supply source is controlled to set the rate at which the treatment liquid is discharged from the nozzle at the end of the coating scan. The discharge rate is temporarily increased from the discharge rate to a second discharge rate higher than that, and then decreased from the second discharge rate to stop the supply of the processing liquid, and through the nozzle that has reached the scanning end point position. And a controller that sucks a predetermined amount of the processing liquid on the substrate.

  Further, the first coating processing program of the present invention causes the substrate to be processed and the discharge port of the long nozzle to face each other almost horizontally with a small gap, and supplies the processing liquid to the substrate from the nozzle. A coating processing program for forming a coating film of the processing liquid on the substrate by performing coating scanning that moves the nozzle in a relatively horizontal direction while relatively moving the nozzle on the substrate. And setting a scanning end point position to be stopped at the end of the coating scan, and at a final stage of the coating scan, a relative horizontal movement speed of the nozzle with respect to the substrate is substantially equal to zero from a first horizontal movement speed. Decreasing the moving speed to place the nozzle at the scanning end position, and at the end of the coating scan, the gap between the substrate and the nozzle is made smaller than the first distance interval. And at a final stage of the coating scan, the rate at which the processing liquid is discharged from the nozzle is temporarily increased from the first discharge rate to a second discharge rate higher than the first discharge rate. A step of decreasing the second discharge rate to stop the supply of the processing liquid and a step of sucking a predetermined amount of the processing liquid on the substrate by the nozzle that has arrived at the scanning end point position are executed.

  In the first coating method, the coating apparatus, and the coating processing program, the long nozzle relatively moves in the horizontal direction while discharging the processing liquid onto the substrate in a band shape through a minute gap. A coating film of the processing liquid is formed from the front end side to the rear end side of the substrate in the scanning direction. Then, at the end of the coating scan, by increasing the processing liquid discharge rate of the nozzle for a moment at a predetermined scanning position or timing, a raised portion is preferably formed on the coating film on the substrate near the boundary between the film thickness guarantee area and the non-guaranteed area. Form. Immediately after the end of scanning, the processing liquid is sucked or sucked back at the scanning end position on the substrate to remove excess processing liquid at the coating scanning end portion, and the influence of sucking back (sucking action) at that time Is canceled at the processing liquid swell portion, the film thickness in the film thickness guarantee region on the substrate is prevented from becoming below the allowable range. In a preferred aspect of the present invention, the treatment liquid discharge rate is made to reach the second discharge rate when the nozzle passes in the vicinity of the boundary between the film thickness guarantee region and the non-guarantement region in the direction of application scanning.

  In the second coating method of the present invention, the substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a minute gap therebetween, and the processing liquid is discharged from the nozzle to the substrate. A coating end point position where a nozzle is moved relatively in a horizontal direction to form a coating film of the treatment liquid on the substrate, and the nozzle is relatively stopped on the substrate. And at the end of the application scan, the relative horizontal movement speed of the nozzle relative to the substrate is reduced from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero. The gap between the substrate and the nozzle is temporarily increased from a first distance interval to a second distance interval larger than that at the end of the coating scan in the step of placing the nozzle at the scanning end position. Let Next, a step of reducing the second distance interval to a third distance interval smaller than the first distance interval, and a rate at which the processing liquid is discharged from the nozzle at the final stage of the coating scan is a first discharge rate. Increasing the second discharge rate to a larger second discharge rate and then decreasing the second discharge rate to stop the supply of the processing liquid, and the substrate at the nozzle at the scanning end point position. And a step of sucking out a predetermined amount of the above processing liquid.

  The second coating apparatus of the present invention includes a substrate support part for supporting the substrate to be processed substantially horizontally and a long length for discharging the processing liquid with a small gap on the upper surface of the substrate during the coating process. Shaped nozzle, a processing liquid supply source for pumping the processing liquid to the nozzle during the coating process, and a scanning unit for moving the nozzle in a horizontal direction relative to the substrate during the coating process And a lifting unit for moving the nozzle in a vertical direction relative to the substrate, and the scanning unit to control the horizontal movement of the nozzle relative to the substrate at the end of the coating scan. Is reduced from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero, the nozzle is positioned at the scanning end point position, and the elevating unit is controlled to control the application scanning. At the end, between the substrate and the nozzle Increasing the gap from a first distance interval to a second distance interval greater than the first distance interval and then decreasing the gap from the second distance interval to a third distance interval smaller than the first distance interval; By controlling the processing liquid supply source, at a final stage of the coating scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate higher than the first discharge rate, and then the first discharge rate is increased. And a controller that stops the supply of the processing liquid from the discharge rate of 2, and sucks a predetermined amount of the processing liquid on the substrate through the nozzle that has arrived at the scanning end point position.

  The second coating processing program of the present invention is such that the substrate to be processed and the discharge port of the long nozzle are opposed to each other substantially horizontally with a small gap while supplying the processing liquid from the nozzle to the substrate. A coating processing program for performing coating scanning for relatively moving the nozzle in the horizontal direction to form a coating film of the processing liquid on the substrate, and relatively stopping the nozzle on the substrate And a second horizontal movement speed which is substantially equal to zero from the first horizontal movement speed at a final stage of the coating scan and the relative horizontal movement speed of the nozzle with respect to the substrate. And at the final stage of the application scan, the gap between the substrate and the nozzle is larger than the first distance interval. Increasing the distance to a distance distance of 2 and then decreasing the distance distance from the second distance distance to a third distance distance smaller than the first distance distance; A step of temporarily increasing the discharge rate from the first discharge rate to a second discharge rate higher than the first discharge rate and then decreasing the discharge rate from the second discharge rate to stop the supply of the processing liquid; and the scanning end point And a step of sucking a predetermined amount of the processing liquid on the substrate by the nozzle that has arrived at a position.

  In the second coating method, the coating apparatus, and the coating processing program, the long nozzle moves relatively in the horizontal direction while discharging the processing liquid onto the substrate in a band shape through a minute gap. A coating film of the processing liquid is formed from the front end side to the rear end side of the substrate in the scanning direction. Then, at the end of coating scanning, the processing liquid discharge rate of the nozzle is increased momentarily at a predetermined scanning position or timing, and preferably a raised portion is formed on the coating film on the substrate near the boundary between the film thickness guarantee area and the non-guaranteed area. Form. In addition, the coating gap is instantaneously increased in combination with the momentary increase in the discharge rate, so that the side edge of the coating film is constricted inward to further increase the film thickness of the raised portion. Thus, immediately after that, when simultaneously reducing the scanning speed and reducing the coating gap between the nozzle and the substrate, the coating film near the boundary between the guaranteed region and the non-guaranteed region in the scanning direction on the substrate. The spread in the side direction can be prevented or suppressed. Immediately after the end of scanning, the processing liquid is sucked or sucked back at the scanning end position on the substrate to remove excess processing liquid at the coating scanning end portion, and the influence of sucking back (sucking action) at that time Is canceled at the constricted portion, the film thickness of the processing liquid in the film thickness guarantee region on the substrate is prevented from becoming below the allowable range. In a preferred aspect of the present invention, the gap is made to reach the second distance interval in the vicinity of the nozzle passing near the boundary between the film thickness guarantee region and the non-guaranteed region in the coating scan direction.

  According to a preferred aspect of the present invention, in order to improve the spread of the processing liquid at the coating scanning end portion and the stability and reproducibility of the film thickness, the suction of the processing liquid is started when the nozzle arrives at the scanning end position. A predetermined delay time is set until

  Furthermore, according to a preferred aspect of the present invention, immediately after finishing the sucking of the processing liquid by the nozzle at the scanning end point position, the nozzle is separated from the processing liquid on the substrate and sucked together when sucking the processing liquid. In order to discharge the air, the nozzle discharges the processing liquid. And after performing the process liquid discharge for this air discharge | emission, a priming process is performed. In the priming process, the discharge port at the lower end of the nozzle and the top of the cylindrical priming roller face each other with a desired gap at a predetermined priming position, discharge the processing liquid from the nozzle and rotate the priming roller to A liquid film of the processing liquid is formed on the lower end of the substrate. In the coating apparatus of the present invention, preferably, the nozzle has a cavity for temporarily storing the processing liquid before discharge and a slit-shaped discharge passage extending from the cavity to the discharge port, and discharges the processing liquid for air discharge. The amount is set within a range of 1/2 to 1 times the volume of the discharge passage.

  In general, the air in the atmosphere is sucked into the nozzle together with the processing liquid on the substrate just before the end of sucking (sucking back) the processing liquid, and the air immediately after being sucked into the nozzle is in the discharge passage, up to the cavity. Not in. However, if left as it is, the air in the discharge passage diffuses or moves upward relatively soon and mixes with the processing liquid in the cavity. In the present invention, immediately after completion of suck back, the nozzle is retracted upward from the application scanning end position by a necessary minimum distance, and the processing liquid is discharged quickly, so that the nozzle is still sucked in the discharge passage of the nozzle. Soon air is discharged out of the nozzle outlet. At that time, by setting the treatment liquid discharge amount to an appropriate amount (preferably within a range of 1/2 to 1 times the volume of the discharge passage), the air was discharged together with the air while being fully discharged. The treatment liquid can be retained around the nozzle discharge port by surface tension to prevent dripping.

  According to the coating method, the coating apparatus, and the coating processing program of the present invention, the film thickness in the vicinity of the coating scanning end portion when the suck back method is used in the spinless coating method using the long nozzle due to the configuration and operation as described above. The controllability can be improved, and the film thickness controllability in the vicinity of the coating scanning start portion can be improved, and as a result, the coating quality can be greatly improved.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a coating and developing treatment system as a configuration example to which the coating method, the coating apparatus, and the coating processing program of the present invention can be applied. This coating / development processing system is installed in a clean room and uses, for example, an LCD substrate as a substrate to be processed, and performs cleaning, resist coating, pre-baking, development, and post-baking in the photolithography process in the LCD manufacturing process. is there. The exposure process is performed by an external exposure apparatus (not shown) installed adjacent to this system.

  This coating and developing system is roughly divided into a cassette station (C / S) 10, a process station (P / S) 12, and an interface unit (I / F) 14.

  A cassette station (C / S) 10 installed at one end of the system includes a cassette stage 16 on which a predetermined number, for example, four cassettes C for storing a plurality of substrates G can be placed, and a side on the cassette stage 16. And a transport path 17 provided in parallel with the arrangement direction of the cassette C, and a transport mechanism 20 that is movable on the transport path 17 and that allows the substrate C to be taken in and out of the cassette C on the stage 16. The transport mechanism 20 has a means for holding the substrate G, for example, a transport arm, can be operated with four axes of X, Y, Z, and θ, and is transported on the process station (P / S) 12 side described later. And the substrate G can be transferred.

  The process station (P / S) 12 includes, in order from the cassette station (C / S) 10 side, a cleaning process unit 22, a coating process unit 24, and a development process unit 26, a substrate relay unit 23, a chemical solution supply unit 25, and It is provided in a horizontal row via (spaced) the space 27.

  The cleaning process unit 22 includes two scrubber cleaning units (SCR) 28, an upper and lower ultraviolet irradiation / cooling unit (UV / COL) 30, a heating unit (HP) 32, and a cooling unit (COL) 34. Contains.

  The coating process unit 24 includes a spinless resist coating unit (CT) 40, a vacuum drying unit (VD) 42, an upper and lower two-stage adhesion / cooling unit (AD / COL) 46, and an upper and lower two-stage heating / cooling. A unit (HP / COL) 48 and a heating unit (HP) 50 are included.

  The development process unit 26 includes three development units (DEV) 52, two upper and lower two-stage heating / cooling units (HP / COL) 53, and a heating unit (HP) 55.

  Conveying paths 36, 51, and 58 are provided in the longitudinal direction in the center of each process unit 22, 24, and 26, and the conveying devices 38, 54, and 60 move along the conveying paths 36, 51, and 58, respectively. Each unit in the process unit is accessed to carry in / out or carry the substrate G. In this system, in each process part 22, 24, 26, a liquid processing unit (SCR, CT, DEV, etc.) is disposed on one side of the transport paths 36, 51, 58, and heat treatment is performed on the other side. System units (HP, COL, etc.) are arranged.

  The interface unit (I / F) 14 installed at the other end of the system is provided with an extension (substrate transfer unit) 56 and a buffer stage 57 on the side adjacent to the process station 12, and is transported to the side adjacent to the exposure apparatus. A mechanism 59 is provided. The transport mechanism 59 is movable on the transport path 19 extending in the Y direction, and is used to load and unload the substrate G with respect to the buffer stage 57, and to extend from the extension (substrate transfer unit) 56 and the adjacent exposure device. The substrate G is transferred.

FIG. 2 shows a processing procedure in this coating and developing processing system. First, in the cassette station (C / S) 10, the transport mechanism 20 takes out one substrate G from a predetermined cassette C on the cassette stage 16, and the cleaning process unit 22 of the process station (P / S) 12. It is transferred to the conveying device 38 (step S1).
In the cleaning process section 22, the substrate G is first sequentially carried into an ultraviolet irradiation / cooling unit (UV / COL) 30, subjected to dry cleaning by ultraviolet irradiation in the first ultraviolet irradiation unit (UV), and then subjected to the next cooling unit ( In COL), the temperature is cooled to a predetermined temperature (step S2). This UV cleaning mainly removes organic substances on the substrate surface.

  Next, the substrate G is subjected to a scrubbing cleaning process by one of the scrubber cleaning units (SCR) 28 to remove particulate dirt from the substrate surface (step S3). After the scrubbing cleaning, the substrate G is subjected to dehydration treatment by heating in the heating unit (HP) 32 (step S4), and then cooled to a constant substrate temperature by the cooling unit (COL) 34 (step S5). Thus, the pretreatment in the cleaning process unit 22 is completed, and the substrate G is transferred to the coating process unit 24 by the transfer device 38 via the substrate transfer unit 23.

  In the coating process unit 24, the substrate G is first sequentially carried into an adhesion / cooling unit (AD / COL) 46, and undergoes a hydrophobic treatment (HMDS) in the first adhesion unit (AD) (step S6). The cooling unit (COL) cools to a constant substrate temperature (step S7).

  Thereafter, the substrate G is coated with a resist solution by a spinless method in a resist coating unit (CT) 40, and then subjected to a drying process by reduced pressure in a reduced pressure drying unit (VD) 42 (step S8).

  Next, the substrate G is sequentially carried into the heating / cooling unit (HP / COL) 48, and the first heating unit (HP) performs baking after coating (pre-baking) (step S9), and then the cooling unit ( COL) to cool to a constant substrate temperature (step S10). In addition, the heating unit (HP) 50 can also be used for baking after this application | coating.

  After the coating process, the substrate G is transported to the interface unit (I / F) 14 by the transport device 54 of the coating process unit 24 and the transport device 60 of the development process unit 26, and is passed from there to the exposure apparatus (step). S11). In the exposure apparatus, a predetermined circuit pattern is exposed on the resist on the substrate G. After the pattern exposure, the substrate G is returned from the exposure apparatus to the interface unit (I / F) 14. The transport mechanism 59 of the interface unit (I / F) 14 passes the substrate G received from the exposure apparatus to the development process unit 26 of the process station (P / S) 12 via the extension 56 (step S11).

  In the development process unit 26, the substrate G is subjected to development processing in any one of the development units (DEV) 52 (step S12), and then sequentially carried into one of the heating / cooling units (HP / COL) 53, Post baking is performed in the first heating unit (HP) (step S13), and then the substrate is cooled to a constant substrate temperature in the cooling unit (COL) (step S14). A heating unit (HP) 55 can also be used for this post-baking.

  The substrate G that has undergone a series of processing in the development process section 26 is returned to the cassette station (C / S) 10 by the transfer devices 60, 54, and 38 in the process station (P / S) 24, where the transfer mechanism 20 Is stored in one of the cassettes C (step S1).

  In this coating and developing system, the present invention can be applied to, for example, the resist coating unit (CT) 40 of the coating process unit 24. Hereinafter, an embodiment in which the present invention is applied to a resist coating unit (CT) 40 will be described with reference to FIGS.

  FIG. 3 shows the overall configuration of the resist coating unit (CT) 40 and the vacuum drying unit (VD) 42 in this embodiment.

As shown in FIG. 3, a resist coating unit (CT) 40 and a vacuum drying unit (VD) 42 are arranged in a horizontal row on the support base or support frame 70 in the X direction. A new substrate G to be subjected to the coating process is carried into the resist coating unit (CT) 40 as indicated by an arrow F _A by the transfer device 54 (FIG. 1) on the transfer path 51 side. Substrate G after completion of the coating process in the resist coating unit (CT) 40 is a transfer arm 74 which is movable in the X direction is guided by the guide rails 72 on the support table 70, a vacuum drying unit as indicated by the arrow F _B (VD) 42. Substrate G having been subjected to the drying treatment in a vacuum drying unit (VD) 42 is drawn off as shown by the arrow F _C by the transfer device 54 of the transport path 51 side (FIG. 1).

  The resist coating unit (CT) 40 includes a stage 76 that extends long in the X direction, and a long shape disposed above the stage 76 while carrying the substrate G in a flat flow on the stage 76 in the same direction. A resist solution is supplied onto the substrate G from the resist nozzle 78, and a resist coating film having a constant film thickness is formed on the upper surface (surface to be processed) of the substrate by a spinless method. The configuration and operation of each part in the unit (CT) 40 will be described in detail later.

  The vacuum drying unit (VD) 42 includes a tray or shallow container type lower chamber 80 having an open upper surface, and a lid-shaped upper chamber configured to be tightly fitted or fitted to the upper surface of the lower chamber 80. (Not shown). The lower chamber 80 is substantially rectangular, and a stage 82 for placing and supporting the substrate G horizontally is disposed at the center, and exhaust ports 83 are provided at the four corners of the bottom surface. Each exhaust port 83 communicates with a vacuum pump (not shown) through an exhaust pipe (not shown). With the lower chamber 80 covered with the upper chamber, the sealed processing space in both chambers can be depressurized to a predetermined degree of vacuum by the vacuum pump.

  4 and 5 show a more detailed overall configuration in the resist coating unit (CT) 40 in one embodiment of the present invention.

  In the resist coating unit (CT) 40 of this embodiment, the stage 76 does not function as a mounting table for fixing and holding the substrate G as in the prior art, but a substrate for floating the substrate G in the air by the force of air pressure. It functions as a levee. Then, the linear movement type substrate transport portions 84 arranged on both sides of the stage 76 hold both side edges of the substrate G floating on the stage 76 in a detachable manner, and the stage longitudinal direction (X direction) The substrate G is transferred to the substrate.

Specifically, the stage 76 is divided into _five regions M ₁ , M ₂ , M ₃ , M ₄ , and M ₅ in the longitudinal direction (X direction) (FIG. 5). The leftmost area M ₁ is a carry-in area, and a new substrate G to be subjected to the coating process is carried into a predetermined position in this area M ₁ . In this carry-in area M ₁ , the substrate G is received from the transfer arm of the transfer device 54 (FIG. 1) and loaded onto the stage 76 so as to move up and down between the original position below the stage and the forward movement position above the stage. A plurality of possible lift pins 86 are provided at predetermined intervals. These lift pins 86 are driven up and down by, for example, a lift pin lift unit 85 (FIG. 13) for carrying in using an air cylinder (not shown) as a drive source.

The loading area M ₁ is also the area substrate transfer of a floating starts, high-pressure or positive pressure to the stage upper surface of the region to float in flying height or flying height H _a for carrying the substrate G A number of jet outlets 88 for jetting compressed air are provided at a constant density. Here, the flying height H _a of the substrate G in the carrying region M ₁ does not require a particularly high accuracy, for example if kept in the range of 250～350Myuemu. Further, it is preferable that the size of the carry-in area M ₁ exceeds the size of the substrate G in the transport direction (X direction). Further, an alignment unit (not shown) for aligning the substrate G on the stage 76 may be provided in the carry-in area M ₁ .

A region M ₃ set at the center of the stage 76 is a resist solution supply region or a coating region, and the substrate G is supplied with the resist solution R from the upper resist nozzle 78 when passing through the coating region M ₃ . The substrate flying height _Hb in the coating region M ₃ defines a coating gap S (for example, 240 μm) between the lower end (discharge port) of the nozzle 78 and the upper surface of the substrate (surface to be processed). The coating gap S is an important parameter that affects the film thickness of the resist coating film and the resist consumption, and must be kept constant with high accuracy. From this, on the upper surface of the stage of the application region M ₃ , for example, a jet that ejects high-pressure or positive-pressure compressed air to float the substrate G with a desired flying height H _b in an arrangement or distribution pattern as shown in FIG. An outlet 88 and a suction port 90 for sucking air with a negative pressure are mixed and provided. Then, a vertical upward force due to compressed air is applied from the jet outlet 88 to a portion passing through the coating region M ₃ of the substrate G, and at the same time, a vertical downward force due to a negative pressure suction force is applied from the suction port 90. In addition, the flying height _Hb for application is maintained in the vicinity of a set value H _S (for example, 50 μm) by controlling the balance of the opposing forces. The size of the coating region M ₃ in the transport direction (X direction) only needs to be large enough to stably form the narrow coating gap S as described above immediately below the resist nozzle 78, and is usually larger than the size of the substrate G. It may be small, for example, about 1/3 to 1/4.

As shown in FIG. 6, in the application region M ₃ , the jet ports 88 and the suction ports 90 are alternately arranged on a straight line C that forms an angle inclined with respect to the substrate transport direction (X direction). An appropriate offset α is provided for the pitch on the straight line C between the columns. According to such an arrangement pattern, not only can the mixing density of the nozzles 88 and the suction ports 90 be made uniform, the substrate levitation force on the stage can be made uniform, but also when the substrate G moves in the transport direction (X direction). It is also possible to make the ratio of the time facing the 88 and the suction port 90 uniform in each part of the substrate, whereby the coating film formed on the substrate G is traced or transferred by the ejection port 88 or the suction port 90. Can be prevented. At the entrance of the coating region M ₃ , the jet outlets 88 arranged in the same direction (on the straight line J) so that the tip of the substrate G stably receives a uniform levitation force in the direction (Y direction) perpendicular to the transport direction, and It is preferable to increase the density of the suction port 90. Also in the coating region M ₃ , it is preferable to arrange only the ejection port 88 at both side edges (on the straight line K) of the stage 76 in order to prevent the both side edges of the substrate G from dripping.

5 again, the middle region M _2, which is set between the loading area M ₁ and the application area M ₃ are, coating the flying height of the substrate G during transport from the flying height H _a of the loading area M ₁ it is a transition region for changing or transition to flying height H _b in the area M _3. Even in the transition region M ₂ , the jet port 88 and the suction port 90 can be mixed and arranged on the upper surface of the stage 76. In that case, the density of the suction port 90 gradually increases along the conveying direction, whereby it as the flying height of the substrate G during transport moves in H _b from progressively H _a. Alternatively, in this transition region M ₂ , a configuration in which only the ejection port 88 is provided without including the suction port 90 is also possible.

A region M ₄ adjacent to the downstream side of the coating region M ₃ is a transition region for changing the flying height of the substrate G from the flying height H _b for coating to the flying height H _c (for example, 250 to 350 μm) during transportation. It is. Even in the transition region M ₄ , the ejection port 88 and the suction port 90 may be mixed on the upper surface of the stage 76, and in this case, the density of the suction port 90 should be gradually reduced along the transport direction. . Alternatively, a configuration in which only the ejection port 88 is provided without including the suction port 90 is also possible. In addition, as shown in FIG. 6, in the transition region M ₄ as well as the coating region M ₃ , the suction port 90 (and the spray nozzle 90) is used to prevent the transfer mark from being applied to the resist coating film formed on the substrate G. It is preferable that the outlet 88) is disposed on a straight line E that forms a certain inclined angle with respect to the substrate transport direction (X direction), and an appropriate offset β is provided in the arrangement pitch between adjacent rows.

A region M ₅ at the downstream end (right end) of the stage 76 is a carry-out region. The resist coating unit (CT) substrate G having received a coating process with 40, the transport arm 74 from a predetermined position or unloading position of the unloading area M ₅ vacuum drying unit on the downstream side next (FIG. 3) (VD) 42 ( 3). In the carry-out area M ₅ , a number of jet outlets 88 for floating the substrate G with a flying height H _c for carrying out are provided on the upper surface of the stage at a constant density, and the substrate G is unloaded from the stage 76. Thus, a plurality of lift pins 92 that can be moved up and down between the original position below the stage and the forward movement position above the stage are provided at predetermined intervals for delivery to the transfer arm 74 (FIG. 3). These lift pins 92 are driven up and down by, for example, a lift pin lift unit 91 (FIG. 13) for carrying out using an air cylinder (not shown) as a drive source.

  The resist nozzle 78 has a length that can cover the substrate G on the stage 76 from one end to the other end, and has a slit-like discharge port 78a at the lower end of a long nozzle body that extends in the horizontal direction (Y direction) perpendicular to the transport direction. And is attached to a nozzle-shaped or inverted U-shaped nozzle support 130 so as to be movable up and down, and is connected to a resist solution supply pipe 94 (FIG. 4) from the resist solution supply mechanism 170 (FIGS. 12 and 13). .

  As shown in FIGS. 4, 7, and 8, the substrate transport unit 84 includes a pair of guide rails 96 arranged in parallel on the left and right sides of the stage 76, and an axial direction (X direction) on each guide rail 96. A slider 98 movably attached to each other, a transport drive unit 100 for moving the slider 98 linearly on each guide rail 96, and right and left side edges of the substrate G extending from each slider 98 toward the center of the stage 76. And a holding portion 102 that holds the detachable holder.

  Here, the conveyance drive unit 100 is configured by a linear drive mechanism such as a linear motor. The holding unit 102 supports the suction pad 104 coupled to the lower surfaces of the left and right side edges of the substrate G by a vacuum suction force, and supports the suction pad 104 at the distal end, with the proximal end on the slider 98 side serving as a fulcrum. And a plate spring type pad support portion 106 that can be elastically deformed so that the height position of each can be changed. The suction pads 104 are arranged in a line at a constant pitch, and the pad support part 106 supports each suction pad 104 independently. As a result, the individual suction pads 104 and the pad support portions 106 can stably hold the substrate G at independent height positions (even at different height positions).

  As shown in FIGS. 7 and 8, the pad support portion 106 in this embodiment is attached to a plate-like pad elevating member 108 attached to the inner surface of the slider 98 so as to be elevable. A pad actuator 109 (FIG. 13) made of, for example, an air cylinder mounted on the slider 98 moves the pad elevating member 108 from the original position (retracted position) lower than the flying height position of the substrate G and the flying height of the substrate G. It is configured to move up and down between the forward movement position (coupling position) corresponding to the position.

  As shown in FIG. 9, each suction pad 104 is provided with a plurality of suction ports 112 on the upper surface of a rectangular parallelepiped pad body 110 made of, for example, synthetic rubber. These suction ports 112 are slit-like long holes, but may be round or rectangular small holes. For example, a belt-like vacuum tube 114 made of synthetic rubber is connected to the suction pad 104. The pipe lines 116 of these vacuum pipes 114 respectively communicate with the vacuum source of the pad suction control unit 115 (FIG. 13).

  As shown in FIG. 4, the holding unit 102 preferably has a separation type or completely independent type in which the vacuum suction pads 104 and the pad support units 106 on one side are separated for each set. However, as shown in FIG. 10, a single plate spring provided with a notch 118 is used to form a pad support portion 120 for one row on one side, and a vacuum suction pad 104 is placed on one row on the pad support portion 120. Configuration is also possible.

As described above, the large number of jets 88 formed on the upper surface of the stage 76, the compressed air supply mechanism 122 (FIG. 11) for supplying the compressed air for generating the levitation force to them, and the coating region M _{3 of the} stage 76. The substrate G is carried in the carry-in area M ₁ and the carry-out area M ₅ by a large number of suction ports 90 formed in the inside of the jet outlet 88 and a vacuum supply mechanism 124 (FIG. 11) for supplying vacuum pressure thereto. A stage substrate floating portion 145 (FIG. 13) for floating the substrate G at a set floating amount H _S suitable for stable and accurate resist coating scanning is formed in the coating region M ₃ . Has been.

FIG. 11 shows the configuration of the nozzle lifting mechanism 75, the nozzle horizontal movement mechanism 77, the compressed air supply mechanism 122, and the vacuum supply mechanism 124. The nozzle raising / lowering mechanism 75 is attached to the gate-shaped frame 130 and the portal frame 130 laid so as to straddle the coating region M _{3 in} the horizontal direction (Y direction) orthogonal to the transport direction (X direction). It has a pair of left and right vertical motion mechanisms 132L and 132R, and a nozzle support 134 of a moving body (lifting body) straddling between these vertical motion mechanisms 132L and 132R. The drive units of the vertical motion mechanisms 132L and 132R include electric motors 138L and 138R made of, for example, pulse motors, ball screws 140L and 140R, and guide members 142L and 142R. The rotational force of the pulse motors 138L and 138R is converted into a linear motion in the vertical direction by the ball screw mechanisms (140L and 142L) and (140R and 142R), and the registration nozzle 78 is moved up and down integrally with the nozzle support 134 of the lifting body. Moving. The amount of elevation movement and the height position of the left and right sides of the registration nozzle 78 can be arbitrarily controlled by the rotation amounts and rotation stop positions of the pulse motors 138L and 138R. The nozzle support 134 is made of, for example, a prismatic rigid body, and a resist nozzle 78 is detachably attached to the lower surface or side surface of the nozzle support 134 via a flange, a bolt, or the like.

  The nozzle horizontal movement mechanism 77 includes a pair of left and right guide rails (not shown) for guiding the portal frame 130 in a horizontal direction (X direction) orthogonal to the longitudinal direction of the nozzle, and the portal frame 130 on the guide rails. It has a pair of left and right horizontal movement mechanisms that move linearly, for example, a pulse motor driven ball screw mechanism 135L, 135R, and is configured so that the portal frame 130 can be positioned at an arbitrary position on the guide rail.

  The compressed air supply mechanism 122 includes a positive pressure manifold 144 connected to a jet outlet 88 for each of a plurality of areas divided on the upper surface of the stage 76, and compressed air from a compressed air supply source 146 of factory force, for example, to the positive pressure manifold 144. Compressed air supply pipe 148 and a regulator 150 provided in the middle of the compressed air supply pipe 148. The vacuum supply mechanism 124 includes a negative pressure manifold 152 connected to the suction port 90 for each of a plurality of areas divided on the upper surface of the stage 76, and a vacuum that feeds, for example, vacuum from a vacuum source 154 of factory power into the negative pressure manifold 152. A pipe 156 and a throttle valve 158 provided in the middle of the vacuum pipe 156 are provided.

  FIG. 12 shows the configuration of the resist solution supply mechanism 170. The resist solution supply mechanism 170 pre-fills the resist pump 176 with the resist solution R for at least one application process (for one substrate) from the bottle 172 storing the resist solution R through the suction pipe 174 to apply the resist solution R. At the time of processing, the resist solution R is sent from the resist pump 176 to the resist nozzle 78 through the discharge pipe or the resist liquid supply pipe 94 at a predetermined pressure, and the resist liquid R is discharged onto the substrate G from the resist nozzle 78 at a predetermined flow rate. It is like that.

The bottle 172 is hermetically sealed, and pressurized gas such as N ₂ gas is supplied at a constant pressure from the gas pipe 178 toward the liquid level in the bottle. The gas pipe 178 is provided with an on-off valve 180 made of an air operated valve, for example.

  A filter 182, a deaeration module 184, and an on-off valve 186 are provided in the middle of the suction pipe 174. The filter 182 removes foreign matter (dust) in the resist solution R sent from the bottle 172, and the degassing module 184 removes bubbles in the resist solution. The on-off valve 186 is composed of, for example, an air operated valve, and turns on (fully opens) or turns off (cuts off) the flow of the resist solution R in the suction pipe 174.

  An open / close valve 188 is provided in the middle of the resist solution supply pipe 94. There is no filter or suckback valve. The on-off valve 188 is composed of, for example, an air operated valve, and turns on (fully opens) or turns off (cuts off) the flow of the resist solution R in the resist solution supply pipe 94.

  The resist pump 176 includes, for example, a syringe pump, and includes a pump main body 190 having a pump chamber, a piston 192 for arbitrarily changing the volume of the pump chamber, and a pump drive unit 194 for reciprocating the piston 192. is doing.

  The resist solution supply control unit 196 is a local controller, and in response to a command from a main controller 200 (FIG. 13) to be described later, each unit in the resist solution supply mechanism 170, particularly the pump drive unit 194 of the resist pump 176 and each on-off valve. 180, 186, 188 and the like are controlled.

  As shown in FIG. 5, the resist coating unit (CT) 40 has a nozzle standby unit 210 disposed slightly upstream from the stage 76 in the substrate transport direction (X direction). A priming processing section is provided in the interior.

  FIG. 34 shows a configuration in the nozzle standby unit 210. As illustrated, the nozzle standby unit 210 has a priming processing unit 212, a solvent atmosphere chamber 214, and a cleaning unit 216 arranged in a horizontal row in the X direction. Among them, the priming processing unit 212 is installed at a location closest to the coating processing position. The straight drive units 135L and 135R of the nozzle horizontal movement mechanism 77 (FIG. 11) extend to the nozzle standby unit 210 (FIG. 3), and the resist nozzle 78 is transferred to each part (212, 214, 216) in the nozzle standby unit 210. It can be done.

The cleaning unit 216 has a nozzle cleaning head 218 that moves or scans in the longitudinal direction (Y direction) under the resist nozzle 78 positioned at a predetermined position. The nozzle cleaning head 218 is equipped with a cleaning nozzle 220 and a gas nozzle 222 for spraying a cleaning liquid (for example, thinner) and a drying gas (for example, N ₂ gas) toward the lower end portion of the resist nozzle 78 and the discharge port 78a. In addition, a drain portion 224 is provided for collecting and collecting the cleaning liquid that has fallen on the resist nozzle 78 with a vacuum force.

  The solvent atmosphere chamber 214 is a length that covers the entire length of the resist nozzle 78 and extends in parallel with the nozzle longitudinal direction (Y direction), and a solvent such as thinner is contained in the chamber. On the upper surface of the solvent atmosphere chamber 214, a V-shaped lid 226 having a slit-like opening 226a extending in the longitudinal direction (Y direction) is attached. When the nozzle portion of the resist nozzle 78 is aligned with the lid 226 from above, only the discharge port 78a and the lower end of the tapered nozzle are exposed to the solvent vapor standing in the room through the opening 226a. Yes. While the coating process is not performed on the stage 76 for a while, the resist nozzle 78 is cleaned by the cleaning unit 216 of the discharge port 78a and the nozzle unit, and then waits in the solvent atmosphere chamber 214.

  In the priming processing unit 212, a columnar priming roller 228 that covers the entire length of the resist nozzle 78 and extends in the horizontal direction (Y direction) is disposed in the solvent bath 230. In the solvent bath 230, a solvent or a cleaning liquid such as a thinner is accommodated at a liquid level such that the lower part of the priming roller 228 is immersed. A rotation support mechanism 232 disposed outside the solvent bath 230 supports the rotation shaft of the priming roller 228 and rotationally drives the priming roller 228. Further, a solvent nozzle 234 for spraying a new solvent onto the outer peripheral surface of the priming roller 228 and a wiper 236 that rubs against the outer peripheral surface of the priming roller 228 are provided in the solvent bath 230 at a position above the cleaning liquid reservoir. Yes. The operation of the priming processing unit 212 will be described later.

  FIG. 13 shows the main configuration of the control system in the resist coating unit (CT) 40 of this embodiment. The controller 200 is formed of a microcomputer, and each part in the unit, in particular, a resist solution supply mechanism 170, a nozzle lifting mechanism 75, a stage substrate floating portion 145, a substrate transport unit 84 (a transport drive unit 100, a pad suction control unit 115, a pad actuator). Eta 109), carry-in lift pin raising / lowering unit 85, carry-out lift pin raising / lowering unit 91, priming roller rotation support mechanism 232, nozzle cleaning head 218, and the like, and individual operations (sequence) are controlled.

  Next, the coating processing operation in the resist coating unit (CT) 40 of this embodiment will be described.

  The controller 200 takes in and executes a coating process program stored in a storage medium such as an optical disk in the main memory, and controls a series of programmed coating process operations.

When the transport device 54 new substrate G (FIG. 1) than the untreated is carried into the carry-area M ₁ stage 76, the lift pins 86 receives the substrate G at the forward position. After conveying device 54 has exited, the lift pins 86 are lowered down to a height position that is floating position H _a for conveying the substrate G (Figure 5). Next, an alignment unit (not shown) is operated, and a pressing member (not shown) is pressed against the floating substrate G from four directions to align the substrate G on the stage 76. When the alignment operation is completed, the pad actuator 109 is actuated immediately after that in the substrate transport section 84, and the suction pad 104 is raised (UP) from the original position (retracted position) to the forward movement position (coupled position). The suction pad 104 is vacuum-on from before, and is bonded by a vacuum suction force as soon as it comes into contact with the side edge of the floating substrate G. Immediately after the suction pad 104 is coupled to the side edge of the substrate G, the alignment unit retracts the pressing member to a predetermined position.

  Next, the substrate transport unit 84 moves the slider 98 straight from the transport start point position to the transport direction (X direction) at a relatively high constant speed while holding the side edge of the substrate G by the holding unit 102. In this way, the substrate G moves straight in the transport direction (X direction) while floating on the stage 76, and when the front end of the substrate G reaches a set position near the position immediately below the resist nozzle 78, the substrate transport unit 84 is the first. Stop substrate transfer in stages. At this time, the nozzle raising / lowering mechanism 75 waits for the resist nozzle 78 at the upper retracted position.

When the substrate G stops, the nozzle raising / lowering mechanism 75 operates to lower the resist nozzle 78 vertically downward, and the distance between the nozzle discharge port and the substrate G or the coating gap is adjusted to the initial value (for example, 60 μm). Next, the resist solution supply mechanism 170 starts discharging the resist solution from the resist nozzle 78 toward the upper surface of the substrate G. At the same time, the substrate transport unit 84 also starts the second stage substrate transport, while the nozzle lifting mechanism 75 The resist nozzle 78 is raised until the coating gap reaches a set value S _A (for example, 240 μm) (for example, for 0.1 second), and thereafter the substrate G is moved horizontally. _A relatively low first speed V _A (for example, 50 mm / s) is selected for the second stage, that is, the substrate conveyance during coating.

Thus, in the coating region M ₃ , the substrate G moves in a horizontal posture at a constant speed V _A in the transport direction (X direction), and at the same time, the long resist nozzle 78 faces the substrate G directly below the resist solution. by discharging R a strip with a constant first pump pressure P _a, the coating film RM of the resist liquid toward the rear side from the front end side of the substrate G, as shown in FIG. 14 is gradually formed. During this coating scanning, the resist solution R discharged onto the substrate G adheres to one side of the resist nozzle 78, that is, the side surface 78b on the back side in the coating scanning direction, and spreads in the height direction due to the wetting phenomenon. ) Extending to) is formed.

In this embodiment, the scanning speed (substrate conveyance speed), the coating gap, and the pump pressure (the output side pressure of the resist pump 176) are controlled as shown in FIG. Changes with different time characteristics. More specifically, the resist solution supply mechanism 170 of the resist pump 176 is controlled under the control of the controller 200 from the time t ₁ when the resist nozzle 78 relatively passes a predetermined passing point X ₁ set on the substrate G. The discharge pressure, that is, the pump pressure is instantaneously increased from the first pump pressure P _A so far to the second pump pressure P _B (for example, P _B = 1.3 P _A ) that is one step higher than that. The rate or flow rate at which the resist solution is discharged from the resist nozzle 78 in the resist solution supply mechanism 170 is proportional to the pump pressure. Accordingly, the instantaneous increase in the pump pressure (P _A → P _B ) increases the flow rate of the resist solution R supplied from the resist nozzle 78 onto the substrate G as shown in FIG. Thus, when the second pump pressure P _B at the peak value is reached at the predetermined time point t ₂ , thereafter, the pump pressure is lowered at once or stepwise to the reference standby pressure P _s set to a value near atmospheric pressure.

On the other hand, in conjunction with a decrease in the pump pressure (P _B → P _S ), under the control of the controller 200, the substrate transport unit 84 changes the scanning speed (substrate transport speed) to the first speed V _A (50 mm). / S) to a second speed V _B that takes a value at or near zero at a predetermined deceleration rate (for example, −100 mm / s ² ), and at the same time, the nozzle lifting mechanism 75 moves the resist nozzle 78 in the vertical direction (Z The coating gap is lowered by a predetermined distance (for example, 140 μm) at a predetermined moving speed (for example, 280 μm / s) in the direction), and the coating gap is increased from the distance distance S _A (240 μm) to a distance distance S _C (100 μm) smaller than that. Narrow.

Here, the passage point X ₁ (or timing t ₁ ) at which the instantaneous increase in pump pressure starts is the characteristics of the resist solution (viscosity, etc.), application conditions (film thickness, standard scanning speed, etc.), application specifications ( The size may be appropriately selected according to the margin size. Preferably, the upper surface (surface to be processed) of the substrate G is set on the inner side so that the pump pressure reaches the second pump pressure P _B having a peak value around the resist nozzle 78 relatively passing the guaranteed region boundary L _X. A boundary (hereinafter referred to as “guaranteed area boundary”) L _X that is divided in half into a product area (film thickness guaranteed area) E _S and an outer margin area (film thickness non-guaranteed area) E _M (guaranteed area E the pass point X ₁ may be set in _S). Similarly, a passing point or timing at which the scanning speed (substrate conveyance speed) and the reduction of the coating gap are started are also selected as appropriate.

FIG. 17 shows how the coating gap also decreases while the scanning speed decreases between the resist nozzle 78 and the substrate G just before the end of coating scanning. As shown in the figure, a local bulge RK of the resist coating film is formed in the vicinity of the guaranteed region boundary L _X where the discharge rate of the resist nozzle 78 increases momentarily.

Thus the resist nozzle 78 is therefore temporarily stops arrived at preset scanning end position X _e on the substrate G at the predetermined time t ₃ (FIG. 18), when the pump pressure is a predetermined one behind this same time or phase At t ₄ , the reference standby pressure P _s near atmospheric pressure is reached, and the resist solution discharge operation ends (FIG. 15). Then, even after the pump pressure has dropped to the reference standby pressure P _s , the pause state is maintained for a while. During this time, the resist solution R spreads from the discharge port 78a of the resist nozzle 78 to the periphery, particularly in the horizontal direction (Y direction) perpendicular to the application scan, and reaches the corner of the rear end of the substrate fully.

Next, the resist solution supply mechanism 170 causes the resist pump 176 to perform a suction operation after a lapse of a predetermined time T _s from the time point t ₄ when the pump pressure drops to the reference standby pressure P _s . That is, in the configuration example of FIG. 12, the piston 192 is moved backward by a fixed stroke. The resist nozzle 78 by blotting the resist solution R on the substrate G by the pump suction operation, the resist film thickness of the coating film RM towards the inside of the substrate G from the scanning end position X _e decreases. Resist liquid supply mechanism 170, lower pump pressure to a predetermined suction pressure P _C, immediately returned to the reference standby pressure P _s. Thus, the resist liquid R of the fixed amount from the substrate G is sucked into the resist nozzle 78 at a scanning end position X _e immediately after the end of the application scan.

In this embodiment, a raised portion RK is formed in the vicinity of the guaranteed region boundary L _{X in} the process of coating scanning as described above, and the resist of the raised portion RK is removed during sucking (suck back) immediately after the end of scanning as described above. by liquid is drawn to the scanning end position X _e side, as shown in FIG. 19, guarantee area boundary L around _X (especially guaranteed area E _S) resist film thickness of the coating film RM set value or within the allowable range of Adjusted or retained.

After suck-back at the scanning end position X _e as described above is carried out, under the control of the controller 200 moves the nozzle lift mechanism 75 is a resist nozzle 78 upward (retreat), where the resist solution supply mechanism 170 However, in order to discharge (discharge) air from the resist nozzle 78, the pump pressure is momentarily increased to the positive pressure side to cause the resist nozzle R to discharge a predetermined amount of resist liquid R. The function and operation of this nozzle air discharge will be described in detail later.

On the other hand, under the control of the controller 200, the substrate conveying section 84 resumes the substrate conveyed to the unloading area M _5. This final stage substrate conveyance is performed at a larger conveyance speed than during the application scanning. When the substrate G arrives at the conveying end position in the unloading area M _5, the substrate conveying unit 84 to stop the substrate carrying the third stage. Immediately after this, the supply of the vacuum to the suction pad 104 is stopped, and the suction pad 104 descends from the forward movement position (coupling position) to the original position (retraction position) and is separated from both end portions of the substrate G. Instead, the lift pins 92 rise from the original position below the stage to the forward movement position above the stage in order to unload the substrate G.

Thereafter, the unloader, that is, the transfer arm 74 accesses the unloading area M ₅ , receives the substrate G from the lift pins 92, and unloads it out of the stage 76. The substrate transport unit 84 immediately returns the substrate G to the loading region M ₁ at a high speed when the substrate G is transferred to the lift pins 92. When the processed substrate G is unloaded as described above in the unloading area M ₅ , loading, alignment, or transfer start is performed on the new substrate G to be subjected to the next coating process in the loading area M ₁ .

As described above, in this embodiment, at the end of the coating scan, the pump pressure of the resist solution supply mechanism 170, that is, the resist solution discharge rate, is increased for a moment, thereby increasing the RK of the resist coating film near the guaranteed region boundary L _X. Form. Then, scan end by causing the suck back to the resist nozzle 78 at a scanning end position X _e on the substrate G immediately remove excess resist liquid coating scan end portion, the influence of the suck-back at that time (blotting action) it is possible to prevent the by resist solution cancel protuberances RK of membrane, the resist film thickness in the guarantee area E _s becomes below the set value also allowable range.

FIGS. 20 to 22 show, as a comparative example, the operation when the step of increasing the pump pressure (resist solution discharge rate) for a moment at the end of the coating scan is omitted. In this case, as shown in FIGS. 20 and 21, the resist liquid film maintaining a substantially constant thickness up to scan end position X _e on the substrate G, the resist coating film in the protuberances near guaranteed area boundary L _X Not formed. Then, when the resist nozzle 78 is stopped at the scanning end position X _e performs a suck back, guarantee area boundary L resist coating liquid in the vicinity of _X is also attracted to the scanning end position X _e side result, as shown in FIG. 22, resist film thickness of the coating film RM in guarantee area E _s becomes thinner than the set value.

In the coating processing method (FIG. 15) in the above-described embodiment, the thickness of the resist coating film is controlled in the scanning direction (−X direction) at the end of coating scanning. However, when the suck back method is used, it may be necessary to control the film thickness from another angle in the horizontal direction (Y direction) orthogonal to the scanning direction. That is, in the suck back method, as described above, the scanning speed and the coating gap are simultaneously reduced between the resist nozzle 78 and the substrate G just before the end of the coating scanning. As shown in FIG. The resist coating film RM spreads over a wide range from the vicinity of the region boundary L _{X to the} vicinity of the substrate edge in the side direction (Y direction). By the side direction of spread of such a resist coating film RM, the resist film thickness in the guarantee area E _s close to the same direction of the guarantee area boundary L _Y becomes thin, before the start suck back depending on the type of the resist or sack, It may become lighter than the set value or set range after the back end. In such a case, the film thickness control in the scanning direction in the above embodiment may not be able to cope with it.

In order to cope with this problem, the present invention provides effective film thickness control in the horizontal direction or the side direction (Y direction) orthogonal to the scanning direction. In this embodiment, at the end of coating scanning, the scanning speed (substrate transport speed), coating gap, and pump pressure are each changed with time characteristics as shown in FIG. Among these characteristics, what is different from the control of FIG. 15 is the time characteristic of the coating gap. That is, by causing the resist nozzle 78 to move up and down by the nozzle lifting mechanism 75 under the control of the controller 200 at the end of the coating scan, the coating gap is changed from the first distance interval S _A (eg, 240 μm). It is once increased at a predetermined vertical movement speed (for example, 600 μm / s) up to a larger second distance interval S _B (for example, 300 μm), and then the predetermined vertical distance to a minimum distance interval S _C for sucking back (for example, 100 μm). Decrease at the moving speed (for example, 400 μm / s).

The passing point where the coating gap as described above starts to increase from the first distance interval S _A to the second distance interval S _B is also the characteristics of the resist solution (viscosity, etc.) and application conditions (film thickness, scanning speed). Etc.), application specifications (margin size, etc.) may be selected as appropriate, and may usually be set near the guaranteed region boundary L _X in the scanning direction.

24 to 27 show the operation when each part is controlled with the above time characteristics (FIG. 23). First, at the end of the coating scan, the coating gap instantaneously increases in combination with a momentary increase in the pump pressure, that is, the resist solution discharge rate, so that the raised portion RK of the resist coating film is formed as shown in FIG. As shown in FIGS. 25 and 26, the side edge portion (end portion in the Y direction) of the resist coating solution RM is moved inward (necked), and the film thickness is increased. . Thus, immediately after that, even if the scanning speed is reduced and the coating gap is reduced simultaneously between the resist nozzle 78 and the substrate G, as shown in FIG. 27, in the vicinity of the guarantee region boundary L _X in the scanning direction. The spreading of the resist coating film RM in the side direction (Y direction) can be prevented or suppressed. However, to put a predetermined period of time before starting suck back in order to stabilize the film thickness applied scan end portion (T _s), the resist coating film side direction near the scanning end position X _e as shown in FIG. 27 While extending to the substrate edge in a distant place from the guarantee area boundary L _X, not very even liquid amount spread.

As understood from comparison with the comparative example (FIG. 28), in this embodiment (FIG. 27), the side edge of the resist coating film RM is narrowed inward in the vicinity of the guarantee region boundary L _{X in the} scanning direction. resist film thickness guaranteed area boundary L _Y guarantee near region E _s of the correspondingly side direction (Y direction) is increased. As a result, when performing the suck-back at the scanning end position X _e, you are possible to resist film thickness in the guarantee area E _s is prevented from becoming thinner than the allowable range at the end of the side direction (Y-direction) .

FIG. 29 shows a film thickness profile on the straight line X _s passing through the guarantee area E _s slightly inside the guarantee area boundary L _Y in the side direction (Y direction) at the rear end of the substrate G in the scanning direction (X direction). An example (FIG. 29) and a comparative example (FIG. 28) are shown in comparison. As shown in FIG. 29, the thickness of the resist coating film RM in the scanning direction is exponentially decreasing towards the scanning end position X _e, not comparative example (FIG. 28) in the margin area EM only guarantee area E _s thinner than the set value D _s at the inner, but can hold the set value D _s in example (Fig. 27) in the guarantee area E _s.

  As described above, in this embodiment, the film thickness control method by increasing / decreasing the coating gap is used in combination with the film thickness control method by instantaneously increasing the treatment liquid discharge rate, so that the film thickness uniformity can be further improved by the synergistic effect of both. This can be further improved. However, depending on the application, it is also possible to use only the film thickness control method by increasing or decreasing the coating gap. 15 and FIG. 23, the timing at which each parameter changes and the mutual timing relationship are merely examples, and various modifications and changes can be made according to the type of resist solution, coating conditions, coating specifications, and the like as described above. is there. For example, in the characteristics shown in FIG. 23, the pump pressure (treatment liquid discharge rate) and the timing for increasing / decreasing the coating gap are made to coincide with each other, but the timings of both can be appropriately shifted.

FIG. 30 and FIG. 31 show the procedure of main steps constituting one cycle of the single wafer coating process in the resist coating unit (CT) 40 of this embodiment. As shown in the figure, coating scanning (step A ₁ ), suck back (step A ₂ ), nozzle air discharge (step A ₃ ), and priming processing (step A ₄ ) are sequentially executed, and after the priming processing (step A ₄ ). The application scan (step A ₁ ) of the next cycle is executed. Among these, the contents of each process of coating scanning (step A ₁ ) and suck back (step A ₂ ) are as described above. Hereinafter, each of the steps will be described the contents of Nozuruea discharge (Step A ₃₎ and priming (Step A _4).

Nozzle air discharge (step A ₃ ) is a process in which the pump pressure is momentarily increased to the positive pressure side immediately after suck back (step A ₂ ), and a predetermined amount of resist solution R is discharged to the resist nozzle 78. It is a characteristic of Specifically, in FIGS. 15 and 23, immediately after the end of suckback (t _{6 to} t ₇ ), the height of the application gap S _c (for example, several mm) at which the nozzle lifting mechanism 75 completely separates the resist nozzle 78 from the substrate G is increased. Immediately thereafter (t _{8 to} t ₉ ), the resist solution supply mechanism 170 changes the pump pressure (output side pressure of the resist pump 176) from the reference standby pressure P _s so far to a predetermined pressure that is a positive pressure. The pressure is instantaneously increased to P _E (for example, P _E = 0.5 to 0.8 P _A ) and immediately returned to the reference standby pressure P _s . As a result, a predetermined amount of the resist solution R is discharged from the discharge port 78a in the resist nozzle 78, and is sucked together with the resist solution on the substrate G at the time of the previous suck back, and the air is discharged.

Rise rate and peak value P _E of the pump pressure in the Nozuruea discharge operation, dripping and that integrity to the air bled from the resist nozzle 78, the underlying resist liquid R out of the discharge nozzles 78a It is set to satisfy the two conditions of not dripping. As will be described later, since the volume of the discharge passage 250 (FIG. 32) in the registration nozzle 78 is only about 1.5 ml (milliliter), for example, even if a discharge amount corresponding to the volume of the discharge passage 250 is set, that is, Even if all of the resist solution in the discharge passage 250 (FIG. 32) is discharged, it is possible to avoid dropping off due to the holding force of the surface tension. Therefore, the resist solution discharge amount in the nozzle air discharge operation may be preferably set within a range of 1/2 times to 1 time the discharge passage volume. Further, the discharge start timing (t ₈ ) is better as the elapsed time from the end of suckback (t ₅ ) is shorter, and may be set within 2 seconds, more preferably within 1 second. In the resist solution supply mechanism 170, the on-off valve 188 of the resist solution supply pipe 94 is kept open even after the suck back is finished, and is closed immediately after the nozzle air discharge operation is finished.

  FIG. 32 shows a specific configuration example of the resist nozzle 78. The illustrated nozzle structure is extremely general, and is configured by abutting two divided nozzle portions 242 and 244 from the left and right with one shim 240 interposed therebetween. A buffer cavity 246 extending in the longitudinal direction of the nozzle is formed on the inner wall of one divided nozzle portion 242, and an introduction passage 248 connecting the external resist solution supply pipe 94 and the buffer chamber 246 is formed inside the other divided nozzle portion 244. Is formed. A slit-like discharge passage 250 is formed between the cavity 246 and the nozzle discharge port 78a at the lower end, and a gap (slit gap) J between the discharge passage 250 and the nozzle discharge port 78a is defined by the thickness of the shim 240. The When the vertical size (land length) of the discharge passage 250 is L and the horizontal size (discharge width) is W, the volume (slit volume) U in the discharge passage 250 is represented by U = J × L × W. The As an example, when J = 60 μm, L = 25 mm, and W = 996 mm, U = 1.494 ml (milliliter).

  As described above, air is sucked into the resist nozzle 78 together with the resist solution on the substrate G as described above, but most of the air enters just before the end of the suck back. That is, when the resist coating film on the substrate G is thinned by suck back and the liquid film level becomes lower than the discharge port 78a of the resist nozzle 78, the surrounding air is mixed with the resist solution on the substrate G and enters the discharge port 78a. Inhaled. Therefore, the air AR immediately after being sucked into the resist nozzle 78 exists in the discharge passage 250 and does not enter the cavity 246.

However, as time elapses, the air AR in the discharge passage 250 diffuses or moves upward, and enters the cavity 246 relatively soon (usually after 4 to 5 seconds have passed since the end of suckback). When the nozzle air discharge (step A ₃ ) of the present embodiment is omitted, at least 4 to 5 seconds or more are required for movement, setup, etc. from the end of suck back (step A ₂ ) to the start of priming process (step A ₄ ). Usually, the air AR enters the cavity 246 from the discharge passage 250 within this time. Once the air AR enters the cavity 246, it mixes with the resist solution R in the cavity 246, and unless the resist nozzle 78 performs a dummy dispense by the cleaning unit 216 (FIG. 34) of the wafer standby unit 210, the air enters the cavity 246. AR is present. In the single-wafer type continuous coating process, in order to increase the production efficiency, only the priming process (step A ₄ ) is performed during standby in one cycle of the coating process as shown in FIG. The air AR mixed into the resist solution in the cavity 246 increases cumulatively as the number of is increased. Then, as described above as a problem of the prior art, the pump pressure is lowered by the mixed air in the cavity 246 at the start of the coating scan (the air bite is generated), thereby reaching the set pressure P _A for coating. As a result, the start-up is delayed, and as a result, the resist coating film at the coating scanning start portion becomes thin.

  In this regard, in this embodiment, the resist nozzle 78 is retracted upward from the coating scanning end position by a necessary minimum distance after the completion of suck back, and the nozzle air discharging operation as described above is executed promptly, thereby performing the resist nozzle 78. The air AR that has just been sucked into the discharge passage 250 is discharged out of the discharge port 78a. At that time, as shown in FIG. 33, the resist solution discharged together with the air AR forms a convex liquid film RB around the discharge port 78a by the surface tension, and remains there without dropping. As described above, since the nozzle air discharging operation is performed as a subsequent process every time application scanning and suck back are performed, the cavity 246 of the resist nozzle 78 can be constantly kept in a state free from air mixing. As a result, it is possible to prevent the occurrence of air biting at the resist nozzle 78 immediately after the start of coating scanning, and consequently to prevent the film thickness of the resist coating film from decreasing at the coating scanning start portion.

In the priming process (step A ₄ ) performed after the nozzle air discharge operation (step A ₃ ), a resist solution is undercoated on the discharge port 78 a of the resist nozzle 78 or the lower part of the back surface 78 for the next coating scan (step A ₁ ). This is preprocessing. Under the control of the controller 200, the nozzle raising / lowering mechanism 75, the nozzle horizontal moving mechanism 77 (FIG. 11) and the like work together to move the resist nozzle 78 to the priming processing section 212 of the nozzle standby section 210, and the resist liquid supply mechanism 170 (FIG. 12) and the priming roller rotation support mechanism 232 (FIG. 34) and the like work together to execute the priming process.

  In this priming process, as shown in FIG. 34, the resist nozzle 78 is close to the priming roller 228 to a position where the discharge port 78a of the resist nozzle 78 faces the top of the priming roller 228 in parallel with a gap Q of the set interval. To do. Under this proximity state, the resist liquid R is discharged to the resist nozzle 78, and simultaneously with or immediately after this, the priming roller 228 is rotated in a certain direction (clockwise in FIG. 35). Then, as shown in an enlarged view in FIG. 35, the resist solution R that has come out from the discharge port 78a of the resist nozzle 78 wraps around the nozzle back surface 78c and is wound around the outer peripheral surface of the priming roller 228. The outer peripheral surface of the priming roller 228 on which the resist solution is taken up immediately enters a solvent bath to wash off the resist solution R. Then, the outer peripheral surface of the priming roller 228 raised from the solvent bath is finished with a new liquid solvent sprayed from the solvent nozzle 234, and immediately after that, the liquid is wiped off by the wiper 236 to restore a clean surface. Then, it passes under the discharge port 78a of the resist nozzle 78 again and receives the resist solution there. The amount of rotation of the priming roller 228 for the priming process may be arbitrary, for example, half rotation. The gap Q formed between the discharge port of the resist nozzle 78 and the priming roller 228 is an application gap S formed between the discharge port of the resist nozzle 78 and the substrate G on the stage 76 during the coating process. It may be set to the same or similar size (for example, 240 μm).

  In this priming process, it is preferable to start the rotation operation of the priming roller 228 after a certain delay time (for example, 1 second) after the resist nozzle 78 starts the resist solution discharge operation. R can be fully and evenly wound around the taper back surface 78c side of the resist nozzle 78. Thus, even after the priming process is completed, a resist solution liquid film that extends straight and uniformly in the longitudinal direction of the nozzle (Y direction) is formed below the discharge port 78a or the back surface 78b of the resist nozzle 78 as shown in FIG. RF remains.

  In the priming process as described above, the liquid film RB adhering to the periphery of the discharge port 78a of the resist nozzle 78 as a result of the nozzle air discharge operation in the previous process is separated from the resist nozzle 78 by the pump pressure immediately after the start of the priming process. Collected by the priming roller 228.

The resist nozzle 78 that has undergone the priming process as described above is subjected to the coating process of the next cycle by the nozzle elevating mechanism 75 and the nozzle horizontal moving mechanism 77 (FIG. 11) at a predetermined timing under the control of the controller 200. It is moved to the application position on the stage 76. That is, as described above, when the unprocessed substrate G is transferred from the carry-in portion M ₁ to the coating region M ₃ , the resist nozzle 78 is lowered to a height position that forms a predetermined initial coating gap with the substrate G. Then, as shown in FIG. 37, the resist solution liquid film RF adhering to the discharge port of the resist nozzle 78 and the lower end on the back adheres to the substrate G so as to block the coating gap of the set size d in a bead shape ( Liquid). Then, when the resist solution supply mechanism 170 starts discharging the resist solution R, the substrate transport unit 84 starts the second-stage substrate transport, whereby the application scanning (step A ₁ ) is performed on the substrate G.

In this case, in the resist solution supply mechanism 170, the discharge operation of the resist pump 176 is started in a state where the air AR is not mixed in the resist nozzle 78 (particularly, in the cavity 246). It rises stably and quickly up to the set value P _A without lowering within 78 (no air biting occurs). As a result, as shown in FIG. 38, the film thickness TH of the resist coating film RM can be controlled within a set value or an allowable range at the coating scanning start portion.

FIG. 39 shows data obtained by measuring the film thickness of the resist coating film formed at the coating scanning start portion in this embodiment in comparison with the case where the nozzle air discharge operation is omitted (comparative example). The film thickness measurement position is selected at a position near the guaranteed area boundary L _X (for example, a position 10 mm inside from the starting edge of the substrate). In the examples, it was confirmed that the film thickness at the coating scanning start portion was stable in the vicinity of the set value (16000 mm) even when the continuous coating treatment was performed 100 times. On the other hand, in the comparative example, as the number of continuous coating processes is increased, the film thickness of the coating scanning start portion decreases exponentially, and when the allowable film thickness range is, for example, ± 5%, the allowable range is only 5 times. It was confirmed that the lower limit value (15200cm) of this was divided.

  The film thickness control at the coating scanning start portion by the nozzle air discharge operation of the present invention can be applied independently to the coating process of the suck back method independently from the film thickness control at the coating scanning end portion.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea. For example, when a tube diaphragm pump is used for the resist pump 176 of the resist solution supply mechanism 170, the pump pressure rise / fall speed is low, and the pump pressure from the peak value P _B to the reference standby pressure P _S at the end of the coating scan. Residual pressure is likely to occur when lowered. In that case, it may be open to residual pressure temporarily by pulling negative pressure side after lowering the tubephragm pump to the reference standby pressure P _S. Further, the present invention is not limited to the levitation conveyance type spinless coating method as in the above embodiment. A substrate is fixedly mounted horizontally on a mounting stage, and a resist solution is discharged onto the substrate in a strip shape while the long resist nozzle is moved in the horizontal direction perpendicular to the longitudinal direction of the nozzle above the substrate. The present invention can also be applied to a spinless coating method.

  Although the above-described embodiment relates to the resist coating apparatus in the coating and developing processing system of LCD manufacturing, the present invention is applicable to any coating method for coating a processing liquid on a substrate to be processed. Therefore, as the processing liquid in the present invention, in addition to the resist liquid, for example, a coating liquid such as an interlayer insulating material, a dielectric material, and a wiring material can be used, and a developing liquid or a rinsing liquid can also be used. The substrate to be processed in the present invention is not limited to an LCD substrate, and other flat panel display substrates, semiconductor wafers, CD substrates, photomasks, printed substrates and the like are also possible.

It is a top view which shows the structure of the application | coating development processing system which can apply this invention. It is a flowchart which shows the procedure of the process in the application | coating development processing system of embodiment. It is a schematic plan view showing the entire configuration of a resist coating unit and a vacuum drying unit in the coating and developing treatment system of the embodiment. It is a perspective view which shows the whole structure of the resist coating unit in embodiment. It is a schematic front view which shows the whole structure of the resist coating unit in embodiment. It is a top view which shows an example of the array pattern of the jet nozzle and suction inlet in the stage application | coating area | region in the said resist application unit. It is a partial cross section schematic side view which shows the structure of the board | substrate conveyance part in the said resist application unit. It is an expanded sectional view which shows the structure of the holding | maintenance part of the board | substrate conveyance part in the said resist application unit. It is a perspective view which shows the structure of the pad part of the board | substrate conveyance part in the said resist application unit. It is a perspective view which shows one modification of the holding | maintenance part of the board | substrate conveyance part in the said resist application unit. It is a figure which shows the structure of the nozzle raising / lowering mechanism, compressed air supply mechanism, and vacuum supply mechanism in the said resist application unit. It is a figure which shows the structure of the resist liquid supply mechanism in the said resist application unit. It is a block diagram which shows the main structures of the control system in the said resist application unit. It is a side view which shows one step of the application | coating scanning in embodiment. It is a timing diagram which shows the time characteristic (1st Example) of the main parameters of the application | coating scanning end stage in embodiment. It is a partial cross section side view which shows the operation | movement of the one step of the application | coating end stage in embodiment. It is a partial cross section side view which shows the operation | movement of the one step of the application | coating end stage in embodiment. It is a partial cross section side view which shows the state at the time of completion | finish of application | coating scanning in embodiment. It is a partial cross section side view which shows the state of the resist coating film at the time of completion | finish of sack back | bag in embodiment. It is a partial cross section side view which shows the operation | movement of the one step just before completion | finish of application | coating scanning in a comparative example. It is a partial cross section side view which shows the state at the time of completion | finish of application | coating scanning in a comparative example. It is a partial cross section side view which shows the state of the resist coating film at the time of completion | finish of sackback in a comparative example. It is a timing diagram which shows the time characteristic (2nd Example) of the main parameters of the application | coating scanning end stage in embodiment. It is a partial cross section side view which shows the operation | movement of the one step of the application | coating end stage in embodiment. It is a partial expanded sectional view which shows the effect | action of the one stage of the application | coating scanning final stage in embodiment. It is a partial enlarged plan view which shows the operation | movement of the one step just before completion | finish of the application | coating scanning in embodiment. It is a partial enlarged plan view showing the state just before the end of application scanning in an embodiment. It is a partial enlarged plan view showing the state just before the end of coating scanning in a comparative example. It is a figure which shows the film thickness profile of the resist coating film in the application | coating scanning termination | terminus part on a board | substrate by contrasting an Example and a comparative example. It is a flowchart figure which shows the procedure of the main processes which comprise 1 cycle of the single wafer application | coating process in embodiment. It is a schematic diagram which shows the procedure of the main process which comprises 1 cycle of the single wafer application | coating process in embodiment. It is a longitudinal cross-sectional view which shows the specific structural example of the resist nozzle used by embodiment. It is a longitudinal cross-sectional view which shows the effect | action of the nozzle air discharge operation | movement in embodiment. It is a partial cross section side view which shows the structure of the nozzle standby part in the said resist application unit. It is a partial cross section side view which shows the priming process in the said resist application unit. It is sectional drawing which shows the liquid film formed in the lower end part of a resist nozzle by a priming process. It is a perspective view which shows a liquid landing state when a long resist nozzle is lowered | hung to the application | coating start position on a board | substrate after a priming process. It is a partial cross section side view which shows the film thickness state of the resist coating film formed in the application | coating scanning start part in embodiment. It is a graph which shows the data which measured the film thickness of the resist coating film formed in the application | coating scanning start part in embodiment.

Explanation of symbols

40 resist coating unit (CT)
75 Nozzle lifting mechanism 76 Stage 78 Resist nozzle 78a Discharge port 84 Substrate transport unit 170 Resist liquid supply mechanism 176 Resist pump 196 Resist liquid supply control unit 200 Controller 246 Cavity 250 Discharge passage

Claims (18)

The substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a small gap, and the nozzle is moved relatively in the horizontal direction while discharging the processing liquid from the nozzle to the substrate. A coating method for performing a coating scan to form a coating film of the treatment liquid on the substrate,
Setting a scanning end point position for relatively stopping the nozzle on the substrate;
At the end of the application scan, the nozzle is scanned by reducing the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero. A process of arriving at the end position;
Reducing the gap between the substrate and the nozzle from a first distance interval to a smaller second distance interval at the end of the application scan;
At the end of the application scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate larger than the first discharge rate, and then decreased from the second discharge rate. A step of stopping the supply of the processing liquid;
And a step of sucking a predetermined amount of the processing liquid on the substrate by the nozzle that arrives at the scanning end point position. The substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a small gap, and the nozzle is moved relatively in the horizontal direction while discharging the processing liquid from the nozzle to the substrate. A coating method for performing a coating scan to form a coating film of the treatment liquid on the substrate,
Setting a scanning end point position for relatively stopping the nozzle on the substrate;
At the end of the application scan, the nozzle is scanned by reducing the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero. A process of arriving at the end position;
At the end of the application scan, the gap between the substrate and the nozzle is increased once from a first distance interval to a second distance interval greater than the first distance interval, and then from the second distance interval to the first distance interval. Reducing to a third distance interval smaller than the distance interval;
At the end of the application scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate larger than the first discharge rate, and then decreased from the second discharge rate. A step of stopping the supply of the processing liquid;
And a step of sucking a predetermined amount of the processing liquid on the substrate by the nozzle that arrives at the scanning end point position.   An area where the film thickness of the coating film should be guaranteed is set inside a boundary passing through a position offset from the outer peripheral edge of the substrate by a predetermined distance toward the center of the substrate, and the nozzle is positioned in the coating scanning direction. The coating method according to claim 2, wherein the gap reaches the second distance interval around the vicinity.   An area where the film thickness of the coating film should be guaranteed is set inside a boundary passing through a position offset from the outer peripheral edge of the substrate by a predetermined distance toward the center of the substrate, and the nozzle is positioned in the coating scanning direction. The coating method according to claim 1, wherein the treatment liquid discharge rate reaches the second discharge rate in the vicinity of passing through the vicinity.   The coating method according to any one of claims 1 to 4, wherein the suction of the processing liquid is started after a predetermined time has elapsed since the nozzle arrived at the scanning end point position.   Immediately after finishing the sucking of the processing liquid by the nozzle at the scanning end point position, the nozzle is separated from the processing liquid on the substrate, and the air sucked together at the time of sucking the processing liquid is discharged. The coating method according to claim 1, wherein the nozzle discharges the treatment liquid.   The coating method according to claim 6, wherein the discharge amount is set so that the processing liquid that has flowed out of the discharge port of the nozzle does not drip when the processing liquid is discharged for discharging the air.   In preparation for the next coating process, after discharging the processing liquid for discharging the air, a desired gap is formed between the discharge port at the lower end of the nozzle and the top of the cylindrical priming roller at a predetermined priming position. 8. The method according to claim 6 or 7, further comprising a step of forming a liquid film of the processing liquid on a lower end portion of the nozzle by facing each other and discharging the processing liquid from the nozzle and rotating the priming roller. Application method. A substrate support for supporting the substrate to be processed substantially horizontally;
An elongated nozzle for discharging a processing liquid across a minute gap on the upper surface of the substrate during application scanning;
A treatment liquid supply source for pumping the treatment liquid to the nozzle during application scanning;
A scanning unit for moving the nozzle in a horizontal direction relative to the substrate during application scanning;
An elevating unit for moving the nozzle in a vertical direction relative to the substrate;
Controlling the scanning unit to reduce the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero at the end of the application scan; Then, the nozzle is placed at the scanning end point position, and the lifting / lowering unit is controlled so that the gap between the substrate and the nozzle is smaller than the first distance interval at the final stage of the coating scan. Decreasing to the second distance interval, controlling the processing liquid supply source, and at the end of the coating scan, changing the rate at which the processing liquid is discharged from the nozzle from the first discharge rate to a second discharge higher than that. The rate is once increased to the rate and then decreased from the second discharge rate to stop the supply of the processing liquid, and a predetermined amount of the processing liquid on the substrate is sucked through the nozzle at the scanning end point position. Coating apparatus and a that controller. A substrate support for supporting the substrate to be processed substantially horizontally;
An elongated nozzle for discharging a processing liquid across a small gap on the upper surface of the substrate during the coating process;
A processing liquid supply source for pumping the processing liquid to the nozzle during the coating process;
A scanning unit for moving the nozzle in a horizontal direction relative to the substrate during a coating process;
An elevating unit for moving the nozzle in a vertical direction relative to the substrate;
Controlling the scanning unit to reduce the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero at the end of the application scan; Then, the nozzle is placed at the scanning end point position, and the lift is controlled so that the gap between the substrate and the nozzle is larger than the first distance interval at the end of the coating scan. Increasing to a second distance interval and then decreasing from the second distance interval to a third distance interval smaller than the first distance interval; and controlling the processing liquid supply source to apply the coating At the end of the scan, the rate at which the processing liquid is discharged from the nozzle is temporarily increased from the first discharge rate to a second discharge rate that is higher than the first discharge rate, and then decreased from the second discharge rate. The feed is stopped, and the coating device and a control unit for the predetermined amount of the treatment liquid on the substrate through the nozzle arriving at the scanning end position blotted.   Immediately after finishing the suction of the processing liquid by the nozzle at the scanning end point position, the control unit controls at least one of the scanning part and the elevating part to separate the nozzle from the processing liquid on the substrate, 11. The coating apparatus according to claim 9, wherein the processing liquid supply source is controlled to discharge the processing liquid to the nozzle in order to discharge the air sucked together when the processing liquid is sucked.   The coating apparatus according to claim 11, wherein the discharge amount is set so that the processing liquid that has flowed out of the discharge port of the nozzle does not droop down when the air is discharged. The nozzle has a cavity for temporarily storing the processing liquid before discharge and a slit-like discharge passage extending from the cavity to the discharge port;
The coating apparatus according to claim 11 or 12, wherein a discharge amount of the processing liquid for discharging the air is set within a range of 1/2 to 1 times a volume of the discharge passage.   At a predetermined priming position for preparation of the coating process, the discharge port at the lower end of the nozzle and the top of the cylindrical priming roller face each other with a desired gap therebetween, and the priming roller is rotated while the priming roller is rotated. The coating apparatus according to claim 9, further comprising a priming processing unit that discharges the processing liquid and forms a liquid film of the processing liquid at a lower end portion of the nozzle after completion of the discharging. The substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a small gap, and the nozzle is moved in the horizontal direction while supplying the processing liquid from the nozzle to the substrate. A coating processing program for performing coating scanning and forming a coating film of the processing liquid on the substrate,
Setting a scanning end point position for relatively stopping the nozzle on the substrate;
At the end of the application scan, the nozzle is scanned by reducing the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero. A step to reach the end point;
Reducing the gap between the substrate and the nozzle from a first distance interval to a smaller second distance interval at the end of the application scan;
At the end of the application scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate larger than the first discharge rate, and then decreased from the second discharge rate. A step of stopping the supply of the treatment liquid;
And a step of causing the nozzle attached at the scanning end position to suck a predetermined amount of the processing liquid on the substrate. The substrate to be processed and the discharge port of the long nozzle are opposed substantially horizontally with a minute gap, and the nozzle is relatively moved in the horizontal direction while supplying the processing liquid from the nozzle to the substrate. A coating processing program for performing coating scanning and forming a coating film of the processing liquid on the substrate,
Setting a scanning end point position for relatively stopping the nozzle on the substrate;
At the end of the application scan, the nozzle is scanned by reducing the relative horizontal movement speed of the nozzle relative to the substrate from a first horizontal movement speed to a second horizontal movement speed substantially equal to zero. A step to reach the end point;
At the end of the application scan, the gap between the substrate and the nozzle is increased once from a first distance interval to a second distance interval greater than the first distance interval, and then from the second distance interval to the first distance interval. Reducing to a third distance interval smaller than the distance interval;
At the end of the application scan, the rate at which the processing liquid is discharged from the nozzle is once increased from the first discharge rate to a second discharge rate larger than the first discharge rate, and then decreased from the second discharge rate. A soup for stopping the supply of the treatment liquid;
And a step of causing the nozzle attached at the scanning end position to suck a predetermined amount of the processing liquid on the substrate.   Immediately after finishing the sucking of the processing liquid by the nozzle at the scanning end point position, the nozzle is separated from the processing liquid on the substrate, and the air sucked together at the time of sucking the processing liquid is discharged. The coating processing program according to claim 15 or 16, wherein a step of causing the nozzle to discharge the processing liquid is executed. In preparation for the next coating process, after discharging the processing liquid for discharging the air, a desired gap is formed between the discharge port at the lower end of the nozzle and the top of the cylindrical priming roller at a predetermined priming position. 18. The step of discharging the processing liquid from the nozzle while rotating the priming roller facing each other and forming a liquid film of the processing liquid on the lower end of the nozzle after the discharge is completed is performed. Application processing program.

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