JP4318714B2 - Coating device - Google Patents

Description

The present invention relates to a coating apparatus for forming a coating film of the treatment liquid on the substrate to be processed by the levitation transportation equation.

  In a photolithography process in the manufacturing process of a flat panel display (FPD) such as an LCD, a long resist nozzle having a slit-like discharge port is scanned relatively to form a resist on a substrate to be processed (such as a glass substrate). A spinless coating method in which a liquid is applied is often used.

  As one form of such a spinless coating method, for example, as disclosed in Patent Document 1, a stage for supporting a rectangular substrate to be processed (for example, a glass substrate) for FPD is configured to be a floating type, Then, the substrate is transported in one horizontal direction (stage longitudinal direction) while floating in the air, and the resist solution is directed toward the substrate passing directly under the long resist nozzle installed above the stage at a predetermined position during transport. A levitation transport method is known in which a resist solution is applied from one end to the other end of a substrate by discharging it in a strip shape.

  The levitation transfer method is a conventional nozzle movement method, that is, a substrate is fixed on a suction-type stage, and a resist solution is ejected in a strip shape while moving a long resist nozzle in the horizontal direction above the substrate. Compared with the method of applying a resist solution from one end to the other end, it can be applied and scanned with the long resist nozzle fixed, which is advantageous for increasing the size of the substrate (ie, increasing the thickness of the resist nozzle). Yes.

  A conventional resist coating apparatus that employs a levitation transport method is a pair of guide rails arranged on both the left and right sides of a stage and in parallel along the guide rails in order to levitate and transport a substrate on a levitation stage. A pair of left and right sliders that move linearly, a pair of left and right suction pads that are detachably attached to both left and right sides of the board, and a pair of left and right suction pads that are connected to the left and right sliders, respectively, and the flying height of the board And a connecting member such as a leaf spring that moves up and down following the height.

  Usually, the flying height (flying height) of the substrate is determined by the pressure of gas (generally air) applied to the substrate from the upper surface of the flying stage, and the optimum flying height for each region on the floating stage divided along the transfer direction The amount is set. That is, a stage in which a relatively large flying height of, for example, 250 to 350 μm is set in the regions (loading region and unloading region) at both ends of the stage where the substrate is loaded and unloaded, and the resist solution is supplied onto the substrate from the resist nozzle. In the central area (application area), a small flying height of, for example, 30 to 60 μm is set. Then, when the substrate is levitated and conveyed from the loading area to the unloading area through the coating area on the levitation stage, the flying height of the substrate changes, and each position in the conveying direction follows the flying height of the substrate. The connecting means is displaced up and down.

  In addition, in the levitation transport method, in order to form a certain narrow gap between the resist nozzle and the substrate, not only control for matching the flying height of the substrate to the set value with high accuracy is required, but also the resist The nozzle height position must also be managed accurately. The relative height position or gap of the resist nozzle with respect to the stage is measured during the setting of the device or between operation of the device, and the reference value is determined based on the measured value. Initialization or error correction is performed.

Conventionally, to measure the gap between the stage and the resist nozzle, place a block-shaped jig on the stage so that the measurement point protrudes outside (side) the stage, and use it as the measurement point of the jig. Press the dial gauge stylus from the bottom to measure the height position of the upper surface (reference) of the stage from the gauge reading, then remove the jig and press the dial gauge stylus from the bottom to the lower end of the resist nozzle. The height position of the lower end of the resist nozzle is measured from the gauge reading. Then, the first measurement value (the height position of the upper surface of the stage) is subtracted from the second measurement value (the height position of the lower end of the resist nozzle), and the difference is used as the gap measurement value.
JP 2005-244155 A

  As described above, the conventional levitation transfer type resist coating apparatus variably controls the flying height (floating amount) of the substrate by the gas pressure applied to the substrate from the levitation stage, and the suction pad or connecting member for holding the substrate is provided. The board is displaced up and down following the flying height of the board. However, there has been a problem that the front end portion and the rear end portion of the substrate flutter up and down during floating transportation. That is, at the moment when the front edge of the substrate almost completely covers each row on the stage upper surface or each individual jet or suction port, the floating pressure received from the stage side changes abruptly, causing vertical vibration in the substrate. Even at the moment when the rear end opens each row or each individual spout or suction port to the atmosphere, the levitation pressure changes abruptly, causing vertical vibrations in the substrate. At that time, the suction pad and the connecting member that hold the substrate also vibrate together with the substrate. As described above, when the front end portion and the rear end portion of the substrate are fluttered during levitation conveyance, the film thickness of the resist coating film becomes unstable, and striped coating unevenness may occur.

  In addition, the conventional method using a dial gauge to measure the height position of the resist nozzle as described above is not only troublesome to install and handle the dial gauge but also a contact type. There is a problem that the nozzle is scratched or the gauge stylus is soiled with a resist, which is easily detected erroneously.

The present invention has been made in view of the above-described problems of the prior art, and the flying height of the substrate is such that the front end portion and the rear end portion of the substrate to be processed do not flutter during floating transportation. accurately stably controlled, and a first object to provide a coating equipment of the levitation transportation scheme so as to improve the thickness quality of the coating film.

Furthermore, a second object of the present invention is to provide a levitation conveyance type coating apparatus that can measure the height position of a nozzle simply, safely and accurately.

In order to achieve the first object, the coating apparatus according to the first aspect of the present invention is detachable from a stage that floats a rectangular substrate to be processed by gas pressure, and the substrate that is floating on the stage. A holding unit that holds the substrate in a predetermined transfer direction on the stage and moves the holding unit holding the substrate in the transfer direction to float and transfer the substrate in the transfer direction; A long nozzle disposed above, and in order to form a coating film of the processing liquid on the substrate, the processing liquid is supplied from the nozzle toward the substrate that passes directly below the nozzle in the floating conveyance. And a processing liquid supply unit for discharging, a holding member that holds the four corners of the substrate locally, and a lifting unit for moving the holding member up and down or displacing the holding member. have a door, the coercive The member supports four suction pads each capable of being sucked on the back surfaces of the four corners of the substrate, and supports each of the suction pads at two positions at predetermined intervals in the transport direction. First and second pad support portions.

In the present invention, the holding member of the holding unit provided in the transport unit includes four suction pads that can be sucked on the back surfaces of the four corners of the substrate, and 2 each of which is spaced by a predetermined interval in the transport direction. The first and second pad support portions that regulate and support the displacement in the vertical direction at each location, and stably hold the four corners of the substrate substantially without bending . Thus, even when the floating pressure received from the stage side fluctuates when the conveyance unit floats and conveys the rectangular substrate on the stage, the front end portion of the substrate or the holding portion or the holding member is caused by the rigid holding force or restraining force of the holding portion or holding member. Fluctuation of the rear end can be suppressed.

Oite to one preferred embodiment of the coating apparatus of the present invention, in order to absorb the lifting error between the first and second pad support, both the first and second pad support is a suction pad that has a horizontal rotary shaft to allow rotational displacement in a vertical plane around, that one of the first and second pad support portion having a linear axis which allows linear displacement of the suction pad in a horizontal direction. As a preferable aspect, the elevating unit integrally controls the first and second actuators for independently elevating and driving the first and second pad support units, and the driving operation of the first and second actuators. And an elevation control unit. Here, the first actuator includes a first motor and a first transmission mechanism that converts the rotational driving force of the first motor into a linear motion in the vertical direction of the first pad support portion. Good. The second actuator may include a second motor and a second transmission mechanism that converts a rotational driving force of the second motor into a vertical movement of the second pad support portion.

  As described above, according to the configuration in which the suction pad is moved up and down by two axes and is suction-coupled to the four corners of the substrate, the horizontal posture of the suction pad, and consequently, the level of the front end portion and the rear end portion of the substrate can be stably and reliably maintained.

  In a preferred aspect, the elevation control unit includes first and second encoders for detecting the rotation angles of the first and second motors, respectively, and the elevation movement distance of the first pad support unit is determined. In order to control, the rotation signal of the first motor is controlled by using the output signal of the first encoder as a feedback signal, and the output signal of the second rotary encoder is controlled to control the vertical movement distance of the second pad support part. The amount of rotation of the second motor is controlled as a feedback signal. Or as another suitable one aspect, the raising / lowering control part may have the 1st and 2nd distance sensor for detecting the raising / lowering movement distance of a 1st and 2nd pad support part, respectively. Also in this case, in order to control the up / down movement distance of the first pad support part, the rotation amount of the first motor is controlled by using the output signal of the first distance sensor as a feedback signal, and the second pad support part is raised / lowered. In order to control the movement distance, the rotation amount of the second motor may be controlled using the output signal of the second distance sensor as a feedback signal.

  In a preferred aspect of the present invention, the suction pad fulcrum is provided between the first and second pad support portions so that the height position of the nozzle with respect to the discharge port becomes a uniform level over the entire upper surface of each suction pad. A suction pad leveling adjusting unit that relatively adjusts the height position of the pad is also provided.

  According to a preferred aspect of the present invention, the transport unit is mounted with a pair of guide rails extending in the transport direction on both sides of the stage and a holding unit, and is movable along the guide rails. And a conveyance driving unit that linearly drives along the rail.

In order to achieve the second object, the coating apparatus according to the second aspect of the present invention can attach and detach a stage that floats a rectangular substrate to be processed by gas pressure and the substrate that is floated on the stage. A holding unit that holds the substrate in a predetermined transfer direction on the stage and moves the holding unit holding the substrate in the transfer direction to float and transfer the substrate in the transfer direction; A long nozzle disposed above, and in order to form a coating film of the processing liquid on the substrate, the processing liquid is supplied from the nozzle toward the substrate that passes directly below the nozzle in the floating conveyance. In order to optically measure the distance between the processing liquid supply section to be discharged, the nozzle lifting mechanism for moving the nozzle up and down, and the measurement object directly below, the nozzle or the supporting and supporting nozzle is lifted and lowered integrally. Move An optical distance sensor attached to a nozzle support, wherein the holding portion holds the four corners of the substrate locally and does not flex substantially, and the holding member moves up and down or is displaced. An elevating part for causing the optical distance sensor to measure a distance interval with the suction pad,

In order to achieve the second object, a coating apparatus according to a third aspect of the present invention includes a stage that floats a rectangular substrate to be processed by gas pressure, and the substrate that is in a floating state on the stage. A holding unit that detachably holds, and a transfer unit that moves the holding unit holding the substrate in the transfer direction to float and transfer the substrate in a predetermined transfer direction on the stage; and A long nozzle disposed above the stage, and processing from the nozzle toward the substrate passing directly under the nozzle in the levitation transport to form a coating film of a processing solution on the substrate; A treatment liquid supply section that discharges the liquid, and the holding section holds the four corners of the substrate locally and does not flex substantially, and the holding member moves up and down or is displaced. An elevating part, The serial holding part, attaching the optical position sensor for detecting the height position of the nozzle optically.
This optical position sensor is preferably provided integrally with at least one suction pad, and is preferably provided on both the left and right sides of the stage with the transport direction as the front. As a preferred aspect, the optical position sensor includes a light projecting unit that emits a light beam substantially horizontally at an angle parallel or oblique to the transport direction, and a size that allows a lower end of the nozzle to enter and exit from above. There may be provided a light receiving portion that has a light receiving surface that faces the exit surface of the light projecting portion and directly in front of the light emitting portion, and that generates an electrical signal indicating whether or not the light beam reaches the light receiving surface.

According to the coating apparatus of the present invention , the flying height of the substrate is accurately and stably controlled so that the front end and the rear end of the substrate to be processed do not flutter during floating transportation by the above-described configuration and operation. In addition, the film quality of the coating film can be improved. Furthermore, according to the coating apparatus of this invention, the height position of a nozzle can be measured simply and safely accurately by the structure provided with the above optical position sensors.

  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 one configuration example to which the coating apparatus of the present invention can be applied. The coating and developing processing system 10 is installed in a clean room. For example, a rectangular glass substrate is used as a processing target G, and a series of cleaning, resist coating, pre-baking, developing, post-baking, and the like in a photolithography process in an LCD manufacturing process. The process is performed. The exposure process is performed by an external exposure device 12 installed adjacent to this system.

  In the coating and developing system 10, a horizontally long process station (P / S) 16 is disposed at the center, and a cassette station (C / S) 14 and an interface station (I / F) are disposed at both ends in the longitudinal direction (X direction). ) 18.

  The cassette station (C / S) 14 is a cassette loading / unloading port of the system 10, and arranges up to four cassettes C that can accommodate a plurality of substrates C in a horizontal direction (Y direction) by stacking substrates G in multiple stages. A cassette stage 20 that can be placed, and a transport mechanism 22 that takes in and out the substrate G to and from the cassette C on the stage 20 are provided. The transport mechanism 22 has a transport arm 22a that can hold the substrate G in units of one or two, can operate on four axes of X, Y, Z, and θ, and is adjacent to a process station (P / S). The substrate G can be transferred to and from the 16 side.

  In the process station (P / S) 16, the processing units are arranged in the order of the process flow or the process on a pair of parallel and opposite lines A and B extending in the horizontal system longitudinal direction (X direction).

  More specifically, the upstream process line A from the cassette station (C / S) 14 side to the interface station (I / F) 18 side includes a carry-in unit (IN PASS) 24, a cleaning process unit 26, a first The thermal processing section 28, the coating process section 30, and the second thermal processing section 32 are arranged in a line in this order from the upstream side along the first flat flow path 34.

  More specifically, the carry-in unit (IN PASS) 24 receives the unprocessed substrates G from the transport mechanism 22 of the cassette station (C / S) 14 in units of one or two, and in a predetermined tact one by one. It is configured so as to be fed into one flat flow path 34. The cleaning process unit 24 includes an excimer UV irradiation unit (E-UV) 36 and a scrubber cleaning unit (SCR) 38 in order from the upstream side along the first flat flow path 34. The first thermal processing unit 28 includes an adhesion unit (AD) 40 and a cooling unit (COL) 42 in order from the upstream side.

  The coating process unit 30 includes a pass unit (PASS) 43, a resist coating unit (COT) 44, a pass unit (PASS) 45, and a vacuum drying unit (VD) 46 in order from the upstream side, and a pass unit (PASS) 43, A conveyance device 47 and a bypass conveyance path 49 are provided for detouring the substrate G between the first flat flow conveyance path 34 to the outside (laterally) once between the substrate 45 and the resist coating unit (COT) 44. Yes. More specifically, the upstream pass unit (PASS) 43 passes the substrate G transported in a flat flow from the first thermal processing unit 28 to the transport device 47 of the bypass transport path 49, and the transport device 47 The received substrate G is carried into the resist coating unit (COT) 44 via the bypass conveyance path 49. Then, the transfer device 47 carries out the substrate G that has been subjected to the resist coating process in the resist coating unit (COT) 44 and passes it to the downstream pass unit (PASS) 45 via the bypass transport path 49. The substrate G is again sent from the pass unit (PASS) 45 to the reduced pressure drying unit (VD) 46 by the flat flow on the first flat flow transfer path 34. The reduced-pressure drying unit (VD) 46 has a chamber in which the substrate G can be stored and depressurized, and a transfer mechanism that carries the substrate G in and out of the chamber in a flat flow.

  The second thermal processing unit 32 includes a pre-bake unit (PRE-BAKE) 48 and a cooling unit (COL) 50 in order from the upstream side. A pass unit (PASS) 52 is provided at the end point of the first flat flow conveyance path 34 located adjacent to the downstream side of the second thermal processing unit 32. The substrate G that has been transported in a flat flow on the first flat flow transport path 34 is transferred from the pass unit (PASS) 52 at the end point to the interface station (I / F) 18.

  On the other hand, in the downstream process line B from the interface station (I / F) 18 side to the cassette station (C / S) 14 side, a development unit (DEV) 54, a post-bake unit (POST-BAKE) 56, a cooling unit are provided. A unit (COL) 58, an inspection unit (AP) 60 and a carry-out unit (OUT-PASS) 62 are arranged in a line in this order from the upstream side along the second flat flow path 64. Here, the post-bake unit (POST-BAKE) 56 and the cooling unit (COL) 58 constitute a third thermal processing unit 66. The carry-out unit (OUT PASS) 62 receives the processed substrates G one by one from the second flat-carrying transport path 64 and supplies them to the transport mechanism 22 of the cassette station (C / S) 14 in units of one or two. Configured to pass in.

  An auxiliary transfer space 68 is provided between the process lines A and B. It should be noted that a shuttle (not shown) that can horizontally place the substrates G in units of one sheet may be moved in both directions in the process line direction (X direction) by a drive mechanism (not shown). .

  The interface station (I / F) 18 includes a transfer device 72 for exchanging the substrate G with the first and second flat flow transfer paths 34 and 64 and the adjacent exposure device 12. A rotary stage (R / S) 74 and a peripheral device 76 are arranged around the periphery. The rotary stage (R / S) 74 is a stage that rotates the substrate G in a horizontal plane, and is used to change the orientation of the rectangular substrate G when it is transferred to the exposure apparatus 12. In the peripheral device 76, for example, a titler (TITLER), a peripheral exposure device (EE), and the like are provided on a floor above the second flat flow path 64. Although not shown, a starting point pass unit (PASS) for receiving the substrate G from the transfer device 72 and placing it on the second flat flow transfer path 64 is provided below the peripheral device 76.

  FIG. 2 shows a processing procedure of all steps for one substrate G in this coating and developing processing system. First, in the cassette station (C / S) 14, the transport mechanism 22 takes out one or two substrates G from any one cassette C on the stage 20, and removes the removed substrates G from the process station (P / S). ) It is carried into the carry-in unit (IN PASS) 24 on the process line A side of 16 (step S1). From the carry-in unit (IN PASS) 24, the substrates G are transferred or loaded onto the first flat flow path 34 one by one with a predetermined tact.

  The substrate G put into the first flat transport path 34 is first subjected to an ultraviolet cleaning process and a scrubbing cleaning process by the excimer UV irradiation unit (E-UV) 36 and the scrubber cleaning unit (SCR) 38 in the cleaning process unit 26. Sequentially applied (steps S2, S3). The scrubber cleaning unit (SCR) 38 removes particulate contamination from the substrate surface by performing brushing cleaning and blow cleaning on the substrate G that moves horizontally on the flat flow path 32, and then rinses. Finally, the substrate G is dried using an air knife or the like. When a series of cleaning processes in the scrubber cleaning unit (SCR) 38 is completed, the substrate G passes through the first thermal processing section 28 as it is down the first flat flow path 34.

  In the first thermal processing unit 28, the substrate G is first subjected to an adhesion process using vapor HMDS in the adhesion unit (AD) 40, and the surface to be processed is hydrophobized (step S4). After the completion of this adhesion process, the substrate G is cooled to a predetermined substrate temperature by the cooling unit (COL) 42 (step S5). Thereafter, the substrate G is transported down the first flat flow transport path 34 to the coating process unit 30.

  When entering the coating process unit 30, the substrate G is transferred from the pass unit (PASS) 43 to the resist coating unit (COT) 44 via the bypass transfer path 49, and is spin-lifted for floating transfer using a long slit nozzle. A resist solution is applied to the upper surface (surface to be processed) by the method. Next, it is sent to the reduced pressure drying unit (VD) 46 via the bypass conveyance path 49 and the pass unit (PASS) 45, where it is subjected to a normal temperature drying process under reduced pressure (step S6).

  The substrate G that has left the coating process unit 30 passes through the second thermal processing unit 32 through the first flat flow path 34. In the second thermal processing section 32, the substrate G is first pre-baked by the pre-bake unit (PRE-BAKE) 48 as a heat treatment after resist coating or a heat treatment before exposure (step S7). By this pre-baking, the solvent remaining in the resist film on the substrate G is evaporated and removed, and the adhesion of the resist film to the substrate is enhanced. Next, the substrate G is cooled to a predetermined substrate temperature by the cooling unit (COL) 50 (step S8). Thereafter, the substrate G is taken from the pass unit (PASS) 52 at the end point of the first flat flow transport path 34 to the transport device 72 of the interface station (I / F) 18.

  In the interface station (I / F) 18, the substrate G is subjected to, for example, a 90-degree direction change by the rotary stage 74 and then carried into the peripheral exposure device (EE) of the peripheral device 76, where it adheres to the peripheral portion of the substrate G. After receiving the exposure for removing the resist to be developed, the resist is sent to the adjacent exposure apparatus 12 (step S9).

  In the exposure apparatus 12, a predetermined circuit pattern is exposed to the resist on the substrate G. Then, when the substrate G that has undergone pattern exposure is returned from the exposure apparatus 12 to the interface station (I / F) 18 (step S9), it is first carried into a titler (TITLER) of the peripheral device 76, where there is a predetermined on the substrate. Predetermined information is written in the part (step S10). Thereafter, the substrate G is carried from the transfer device 72 to the start point path unit (PASS) of the second flat flow transfer path 64 laid on the process line B side of the process station (P / S) 16.

  In this way, the substrate G is transferred on the second flat flow transfer path 64 toward the downstream side of the process line B. In the first development unit (DEV) 54, the substrate G is subjected to a series of development processes of development, rinsing, and drying while being conveyed in a flat flow (step S11).

  The substrate G that has undergone a series of development processes in the development unit (DEV) 54 is sequentially passed through the third thermal processing unit 66 and the inspection unit (AP) 60 while being put on the second flat flow path 64 as it is. To do. In the third thermal processing section 66, the substrate G is first subjected to post-baking as post-development heat treatment in the post-bake unit (POST-BAKE) 56 (step S12). By this post-baking, the developing solution and the cleaning solution remaining in the resist film on the substrate G are removed by evaporation, and the adhesion of the resist pattern to the substrate is enhanced. Next, the substrate G is cooled to a predetermined substrate temperature by the cooling unit (COL) 58 (step S13). In the inspection unit (AP) 60, non-contact line width inspection, film quality / film thickness inspection, and the like are performed on the resist pattern on the substrate G (step S14).

  The carry-out unit (OUT PASS) 62 receives the substrates G that have been processed in all processes from the second flat-carrying transport path 64 one by one, and the cassette station (C / S) 14 in units of one or two. To the transport mechanism 22. On the cassette station (C / S) 14 side, the transport mechanism 22 receives either one (usually the original) processed substrate G received from the carry-out unit (OUT PASS) 62 in units of one or two. Housed in cassette C (step S1).

  In the coating and developing treatment system 10, the present invention can be applied to the resist coating unit (COT) 44 in the coating process unit 30. Hereinafter, an embodiment in which the present invention is applied to a resist coating unit (COT) 44 will be described in detail with reference to FIGS.

  3 to 5 show the overall configuration of the resist coating unit (COT) 44 in this embodiment, FIG. 3 is a schematic plan view, FIG. 4 is a perspective view, and FIG. 5 is a schematic front view.

As shown in FIG. 3, the resist coating unit (COT) 44 includes a stage 80 that extends long in the transport direction (X direction) of the first flat flow transport path 34 (FIG. 1). A new substrate G to be subjected to the coating process is carried into the area (carrying area M ₁ ) at the conveyance upstream end of the stage 80 from the bypass conveyance path 49 by the conveyance device 47 as indicated by the arrow F _A. Then, the substrate G that has undergone the spinless resist coating process by the floating conveyance as indicated by the arrow F _B on the stage 80 is indicated by the arrow F _C from the conveyance downstream end area (unloading area M ₅ ) of the stage 80. Then, it is taken up by the transfer device 47 on the bypass transfer path 49 side. A long resist nozzle 82 for supplying a resist solution to the substrate G is disposed above the central region (application region M ₃ ) of the stage 80 in the longitudinal direction.

  As shown in FIG. 4, the stage 80 is configured as a floating stage that floats the substrate G in the air by the force of gas pressure, and a plurality of outlets 88 that eject a predetermined gas (usually air) on the upper surface thereof. Is formed on one side. Then, the linearly-moving-type substrate transfer units 84 arranged on the left and right sides of the stage 80 hold the substrate G floating on the stage 80 in a detachable manner and transfer the substrate G in the longitudinal direction of the stage (X direction). It is supposed to be. On the stage 80, the substrate G is levitated and transported in a horizontal posture in which the pair of sides are parallel to the transport direction (X direction) and the other pair of sides are orthogonal to the transport direction.

The stage 80 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 region M ₁ is a carry-in region, and a new substrate G to be subjected to the coating process is carried into the carry-in region M ₁ from the bypass conveyance path 49 as described above with reference to FIG. In this carry-in area M ₁ , a plurality of substrates that can move up and down between the original position below the stage and the forward movement position above the stage in order to receive the substrate G from the transfer arm of the transfer device 47 and load it onto the stage 80. The lift pins 86 are provided at predetermined intervals. These lift pins 86 are driven up and down by a carry-in lift pin lift unit 85 (FIG. 12) using, for example, an air cylinder (not shown) as a drive source.

The loading area M ₁ is also a region levitation transportation of the substrate G is started, the 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 80 may be provided in the carry-in area M ₁ .

A region M ₃ set at the center in the longitudinal direction of the stage 80 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 82 when passing through the coating region M _3. receive. The substrate flying height _Hb in the coating region M ₃ defines a coating gap S (for example, 200 μm) between the lower end (discharge port) of the resist nozzle 80 and the substrate upper surface (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. For this reason, on the upper surface of the stage in the application region M ₃ , for example, an ejection port that ejects high-pressure or positive-pressure compressed air to float the substrate G at a desired flying height H _b in an arrangement pattern as shown in FIG. 88 and a suction port 90 for sucking air with negative pressure are provided in a mixed manner. Then, a vertical upward force by compressed air is applied from the jet outlet 88 to a portion located in the coating region M ₃ of the substrate G, and at the same time, a vertical downward force by 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 (for example, 30 to 50 μm) by controlling the balance of the opposing forces that oppose each other.

The size of the coating region M ₃ in the transport direction (X direction) is sufficient if there is enough room to stably form the narrow coating gap S as described above immediately below the resist nozzle 82, 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 ejection ports 88 and the suction ports 90 are alternately arranged adjacent to each other on a straight line C that forms a certain inclined angle with respect to the transport direction (X direction). An appropriate offset α is provided for the pitch on the straight line C between the rows. According to such an arrangement pattern, not only can the mixing density of the ejection ports 88 and the suction ports 90 be made uniform so that the substrate levitation force on the stage 80 is 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 outlet 88 and the suction port 90 uniform in each part of the substrate, whereby traces or transfer traces of the jet port 88 or the suction port 90 are formed on the coating film formed on the substrate G. It can be prevented from sticking. 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 ports 88 at both side edges (on the straight line K) of the stage 80 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, the flying height H _a flying height of the substrate G in the carrying region M ₁ during transport it is a transition region for changing or transition flying to a height H _b in the coating 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 80. 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 , it is possible to adopt a configuration in which only the spout 88 is provided in an appropriate arrangement pattern without including the suction port 90.

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. Also 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 80, and in that 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 in an appropriate arrangement pattern 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 80 is a carry-out region. The resist coating unit (COT) 44 substrate G received the coating process, the carry-out area M ₅ from the transport apparatus 47 vacuum drying unit via the bypass conveying path 49 (FIG. 1) downstream (VD) 46 ( 1). In the carry-out area M ₅ , a number of jet outlets 88 for floating the substrate G with the 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 80. 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. These lift pins 92 are driven up and down by an unloading lift pin lifting / lowering unit 95 (FIG. 12) using, for example, an air cylinder (not shown) as a drive source.

  The resist nozzle 82 has a slit-like discharge port 82a that can cover the substrate G on the stage 80 from one end to the other end, and is attached to a gate-shaped or inverted U-shaped frame 138 (FIGS. 3 and 11) so as to be movable up and down. And connected to a resist solution supply pipe 98 (FIG. 4) from the resist solution supply mechanism 96 (FIG. 12).

  As shown in FIGS. 3, 4, and 7, the substrate transport unit 84 includes a pair of left and right guide rails 100 </ b> L and 100 </ b> R arranged in parallel on both sides of the stage 80, and a transport direction on these guide rails 100 </ b> L and 100 </ b> R. A pair of left and right sliders 102L and 102R attached so as to be movable in the (X direction), a transport drive unit 104 that linearly moves both sliders 102L and 102 simultaneously or in parallel on both guide rails 100L and 100R, and a substrate G A holding portion 106 mounted on both the sliders 102L and 102 is provided in order to be detachably held. The conveyance drive unit 104 is configured by a linear drive mechanism such as a linear motor.

  As shown in FIGS. 3, 4, and 7 to 9, the holding unit 106 includes four suction pads 108 (1) and 108 (2) that are bonded to the back surfaces (lower surfaces) of the four corners of the substrate G by vacuum suction force. ), 108 (3), 108 (4), and the suction pads 108 (i) (i = 1 to 4) are restricted in vertical displacement at two positions spaced apart in the transport direction (X direction). And a pair of pad actuators 112a and 112b for moving the pair of pad support portions 110a and 110b up and down independently or moving them up and down independently.

  More specifically, each suction pad 108 (i) is provided with a plurality of suction ports 114 on the upper surface of a rectangular parallelepiped pad body made of, for example, stainless steel (SUS), as shown in FIGS. . Further, in the illustrated configuration example, a rubber bellows 116 is partly exposed and attached to each suction port 114 in order to enhance adhesion or adsorption force to the substrate. Each suction port 114 is connected to an external vacuum tube 118 (FIG. 8) via a vacuum passage in the pad main body. The vacuum tube 118 communicates with a vacuum source (not shown) of the pad suction control unit 115 (FIG. 12).

  The pad support portions 110a and 110b are L-shaped rigid bars made of, for example, stainless steel (SUS). The front pad support portion 110a has a lower end portion (base end portion) extending in the vertical direction and coupled to the front pad actuator 112a, and an upper end portion extending in the horizontal direction so that the suction pad 108 (i) Connected to the front. The rear pad support 110b has a lower end (base end) that extends in the vertical direction and is coupled to the rear pad actuator 112b, and an upper end that extends in the horizontal direction to the rear of the suction pad 108 (i). Are combined.

Here, the connection relationship between the suction pad 108 (i) and the two pad support portions 110a and 110b is preferably configured so that the lifting error between the two pad support portions 110a and 110b can be absorbed on the suction pad 108 (i) side. For this purpose, both of the pad support portions 110a and 110b have a horizontal rotation shaft that allows the suction pad 108 (i) to be rotationally displaced in the vertical plane around it, and one of the pad support portions 110a and 110b. However, it is preferable that the suction pad 108 (i) has a linear motion shaft that can be linearly displaced in the horizontal direction. In this embodiment, for example, as shown in FIG. 10, the front bearing 122a is attached to the front part of the suction pad 108 (i) via the joint part 120a, and the X-direction straight line is attached to the rear part of the suction pad 108 (i). Install the rear bearing 122b through the dynamic guide 120b, respectively coupled both pad support 110a, a horizontal upper portion of 110b to the front bearing 122a and a rear bearing 122 b.

  The front pad actuator 112a includes, for example, a servo motor 124a and, for example, a ball screw mechanism integrated with a linear motion guide that converts the rotational driving force of the servo motor 124a into a vertical linear motion of the front pad support portion 110a. And a transmission mechanism 126a. The rear pad actuator 112b is a transmission composed of, for example, a servo motor 120b and, for example, a ball screw mechanism integrated with a linear motion guide that converts the rotational driving force of the servo motor 120b into a linear motion in the vertical direction of the front pad support 110b. And a mechanism 122b. A rotary encoder (not shown) for detecting the respective rotation angles is attached to both servo motors 124a and 124b. By controlling the rotation amounts of both servo motors 124a and 124b using the output signals of these rotary encoders as feedback signals, the vertical movement distances of the front and rear pad support portions 110a and 110b can be made to match substantially accurately. .

  Further, in this embodiment, as shown in FIGS. 8 and 9, in order to further improve the accuracy of the above-described up-and-down movement control with respect to both pad support portions 110a and 110b, the up-and-down positions of both pad support portions 110a and 110b are used. Alternatively, linear scales 124a and 124b for actually measuring and moving up and down the moving distance are provided. Each linear scale 124a, 124b is attached to each pad support part 110a, 110b for optically reading the scale part 126 extending in the Z direction attached to the slider 102L (102R) and the scale part 126. A scale reading unit 128 is included.

  As described above, the holding unit 106 of this embodiment includes a pair of pad actuators 112a and 112b via a pair of rigid pad support portions 110a and 110b that do not substantially deflect each suction pad 108 (i). Therefore, each suction pad 108 (i) can be moved up and down stably while maintaining a fixed posture (particularly a horizontal posture).

  It should be noted that all electrical wiring, piping, and the like that connect each portion mounted on the sliders 102L and 102R to the stationary control unit and power supply source in the substrate transport unit 84 are housed in a flexible cable bear (not shown). ing.

  In FIG. 9, an optical position sensor 130 is attached to the suction pad 108 (1) on the left side of the front row. A similar optical position sensor 130 is also attached to the suction pad 108 (2) on the right side of the front row. This optical position sensor 130 is used for measuring the height position of the resist nozzle 82 in place of the conventional dial gauge, and the configuration and operation thereof will be described in detail later with reference to FIGS. 9, 16, and 17. To do.

As described above, the large number of jets 88 formed on the upper surface of the stage 80, the compressed air supply mechanism 134 (FIG. 11) that supplies compressed air for generating levitation force to them, and the coating region M _{3 of the} stage 80. A 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 a mixed manner with the jet ports 88 and a vacuum supply mechanism 136 (FIG. 11) for supplying vacuum pressure thereto. Stage substrate floating surface 135 for floating at floating heights H _a and H _c suitable for exit and high-speed conveyance, and for floating substrate G at set flying height H _b suitable for stable and accurate resist coating scanning in coating area M _3. (FIG. 12) is configured.

FIG. 11 shows configurations of the nozzle lifting mechanism 132, the compressed air supply mechanism 134, and the vacuum supply mechanism 136. Nozzle elevator mechanism 132 includes a horizontal direction (Y direction) portal frame 138 is bridged so as to cross the perpendicular to the conveying direction (X-direction) over the coating area M _3, mounted on the portal frame 138 A vertical linear motion mechanism 140L, 140R, and a nozzle support 142, which is a moving body (lifting body) horizontally extending, are provided between the vertical linear motion mechanisms 140L, 140R. The drive units of the linear motion mechanisms 140L and 140R include, for example, pulse motors 144L and 144R, ball screws 146L and 146R, and guide members 148L and 148R. The rotational force of the pulse motors 144L and 144R is converted into a linear motion in the vertical direction by the ball screw mechanisms (146L and 148L) and (146R and 148R), and the registration nozzle 82 is moved up and down integrally with the nozzle support 142 of the lifting body. Moving. The up / down movement amount and the height position of the registration nozzle 82 can be arbitrarily controlled by the rotation amount and rotation stop position of the motors 144L, 144R. The nozzle support 142 is made of, for example, a prismatic rigid body, and a resist nozzle 82 is detachably attached to one side thereof via a flange, a bolt, or the like.

  The compressed air supply mechanism 134 includes a positive pressure manifold 150 connected to a jet outlet 88 for each of a plurality of areas divided on the upper surface of the stage 80, and compressed air from a compressed air source 152 of factory power, for example, to the positive pressure manifold 150. A compressed air supply pipe 154 to be fed in and a regulator 156 provided in the middle of the compressed air supply pipe 154 are provided. The vacuum supply mechanism 136 includes a negative pressure manifold 158 connected to the suction port 90 for each of a plurality of areas divided on the upper surface of the stage 80, and a vacuum that sends vacuum from the vacuum source 160 of factory power to the negative pressure manifold 158. It has a pipe 162 and a throttle valve 164 provided in the middle of the vacuum pipe 162.

  In addition, the resist coating unit (COT) 44 is optically connected to the nozzle support 142 as shown in FIG. 11 in order to measure the distance between the resist nozzle 82 and the substrate G or each suction pad 108 (i). The distance sensor 166 (166L, 166R) is attached. The optical distance sensor 166 moves up and down integrally with the nozzle support 142 and the resist nozzle 82, and is spaced from an arbitrary height position, that is, a distance to the substrate G on the stage 80 or each suction pad 108 ( The distance distance from i) can be measured optically. For this optical distance measurement, the optical distance sensor 166 includes a light projecting unit that projects a light beam vertically downward, and light reflected from an object (substrate or suction pad) that is exposed to the light beam. And a light receiving unit that receives light at a position corresponding to the measurement distance. In the illustrated configuration example, the distance from the substrate G or the suction pad 108 (i) is measured on both the left and right sides using a pair of left and right optical distance sensors 166L and 166R.

  FIG. 12 shows the main configuration of the control system in the resist coating unit (COT) 44 of this embodiment. The controller 170 includes one or a plurality of microcomputers, and each part in the unit, in particular, a resist solution supply mechanism 96, a nozzle lifting mechanism 132, a stage substrate floating portion 135, a substrate transfer portion 84 (transfer drive portion 104, pad suction). The control unit 115, the pad actuator 112), the carry-in lift pin lift unit 85, the carry-out lift pin lift unit 95, and other individual operations and the overall operation (sequence) are controlled. In particular, the controller 170 has a program memory for storing a program (software) for executing any control relating to the coating process and any control relating to various additional functions, and a central processing control unit (CPU) of the microcomputer. However, a required program is sequentially read from the program memory and executed. Various storage media such as a hard disk, an optical disk, and a flash memory can be used for program storage management.

  Next, the coating processing operation in the resist coating unit (COT) 44 of this embodiment will be described. The controller 170 controls a series of coating processing operations in accordance with a resist coating processing program stored in the program memory as described above.

When a new unprocessed substrate G is carried into the carry-in area M ₁ of the stage 80 from the transfer device 47 (FIG. 1), the lift pins 86 receive the substrate G at the forward movement position. After the transfer arm of the transfer device 47 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, the alignment unit (not shown) is operated, and a pressing member (not shown) is pressed from four directions to the floating substrate G to align the substrate G on the stage 80. In the width direction (Y direction), the size of the stage 80 is somewhat smaller than the size of the substrate G, and the left and right ends of the substrate G protrude beyond the stage 80 (for example, about 6 to 10 mm). Yes.

The substrate transport unit 84 is waiting in the carry-in unit M ₁ , and when the alignment operation is completed, the four corners of the substrate G and the suction pads 108 (1), 108 (2), 108 (3), 108 ( 4) face each other vertically. Immediately after, the holding unit 106 at each position simultaneously operates the front and rear pad actuators 112a and 112b to move the front and rear pad support units 110a and 110b upward at the same timing and stroke, thereby 108 (i) is raised from the original position (retracted position) to the forward movement position (holding position). Immediately before this, the pad suction control unit 115 turns on the vacuum supply to the suction pads 108 (1) to 108 (4), and the four suction pads 108 ( 1) to 108 (4) are brought into contact with each other from below and bonded by a vacuum adsorption force. In this way, the substrate G receives a pneumatic levitation force from the stage 80 on the entire substrate, and only the four corners thereof are locally sucked and held by the four suction pads 108 (1) to 108 (4) of the holding unit 106. . When the holding unit 106 receives the substrate G, immediately after this, the alignment unit retracts the pressing member to a predetermined position.

Next, the substrate transport unit 84 starts floating transport of the substrate G in a state where the four corners of the substrate G are held by the suction pads 108 (1) to 108 (4) of the holding unit 106. That is, the transport driving unit 104 moves both the left and right sliders 102L and 102R straight from the transport start position to the transport direction (X direction) at a relatively high speed. In this way, the substrate G moves on the stage 80 by levitation conveyance toward the coating region M ₃ , and when the front end portion of the substrate G arrives at a set position near the resist nozzle 82 soon, the substrate conveyance unit 84 performs this operation. The first stage substrate conveyance is stopped. At this time, the nozzle raising / lowering mechanism 132 waits the resist nozzle 82 at the upper retracted position.

When the substrate G stops, the nozzle raising / lowering mechanism 132 operates to lower the registration nozzle 82 vertically downward, and the nozzle lowering operation is stopped when the distance interval or the gap S between the nozzle discharge port 82a and the substrate G reaches the set value. . Next, the resist solution supply mechanism 96 starts discharging the resist solution from the resist nozzle 82 toward the upper surface of the substrate G. On the other hand, the substrate transport unit 84 starts the second-stage substrate transport. _A relatively low constant speed V _A is selected for the second stage, that is, for transporting the substrate 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 82 applies the resist solution R toward the substrate G immediately below. By discharging in a strip shape at a constant flow rate, a coating film RM of resist solution is formed from the front end side to the rear end side of the substrate G as shown in FIG.

When the above-described coating process is completed in the coating region M ₃ , the substrate G is transported toward the carry-out region M ₅ . Here, the substrate transport section 84 switches to the third stage substrate transport with a relatively high transport speed. 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 pad suction control unit 115 stops supplying vacuum to the suction pads 108 (1) to 108 (4), and at the same time, the front and rear pad actuators 112a and 112b of the holding unit 106 are operated, Then, the rear pad support portions 110a and 110b are moved downward at the same timing and stroke to lower each suction pad 108 (i) from the forward movement position (holding position) to the original position (retraction position). Thus, the four suction pads 108 (1) to 108 (4) are separated from the four corners of the substrate G all at once. 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 device 47 accesses the unloading area M _{5 from} the bypass passage 49, receives the substrate G from the lift pins 92, and unloads it from the stage 80. 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, this embodiment locally holds the four corners of the substrate G floating on the stage 80 with the four suction pads 108 (1) to 108 (4) in the substrate transport unit 84, and Each suction pad 108 (i) is supported by a rigid pad support 110 that does not flex substantially, and is moved up and down or displaced up and down to a desired height by the up and down driving force of the pad actuator 112. ing. Moreover, since the pair of pad support portions 110a and 110b and the pair of pad actuators 112a and 112b are driven up and down by two axes and controlled by servo, each suction pad 108 (i) is in a fixed posture (particularly horizontal posture). And can be moved up and down or displaced up and down stably.

  According to such a configuration of the substrate transport unit 84, while the substrate G is levitated and transported on the stage 80, the front end of the substrate G is in each row on the upper surface of the stage or each individual jet port 88 or suction port 90. Even if the flying pressure received from the stage 80 side suddenly fluctuates at the moment when the substrate G is almost completely covered, or at the moment when the rear end of the substrate G opens each row or each individual jet port 88 or suction port 90 to the atmosphere, Flapping of the front end portion or the rear end portion of the substrate G can be suppressed by the rigid holding force or restraining force of the holding portion 106.

Further, when the substrate G is floated and conveyed from the carry-in area M ₁ through the coating area M ₃ to the carry-out area M ₅ on the stage 80, each suction is performed according to the substrate flying height set for each area. The height positions of the pads 108 (1) to 108 (4) can be variably controlled as appropriate.

More specifically, first, immediately after and immediately before starting the floating transfer of the substrate G, as will become substantially horizontal in flying height H _a of the substrate G is set in the loading area M _1, the suction pads 108 (1) ~ 108 (4) can be aligned at the same height position.

Then, when the front end of the substrate G passes through the transition region M ₂ between the loading area M ₁ and the application area M ₃ are, substrate flying height in this interval is to fit the changes from H _a in H _b , front row right and left holding portions 106 are front row each set of pads activator eta (112a, 112b) suction pads 108 (1) of the front row left actuates the, 108 (2) the same height difference at the same timing (H _a -H _b ) Lower only. Thus, when the front end of the substrate G arrived beneath the resist nozzle 82 enters the coating area M _3, when further to start the coating process scan (substrate transfer of the second step), as shown in FIG. 14, the front row By the rigid restraining force of the left and right holding portions 106, the front end portion of the substrate G can be stably and reliably kept horizontal at the set flying height _Hb . Thereby, the uniformity of the film thickness of the resist coating film RM formed on the front end portion of the substrate G can be improved. Incidentally, when the front end of the substrate G is moved immediately below the resist nozzle 82, the rear end of the substrate G is still in carry-area M ₁ in flying height H _a.

Further, when the rear end of the substrate G passes through the transition region M ₂ also, the holding portion 106 is back row each set of pads activator eta (112a, 112b) to actuate the rear row of suction pads 108 (3), 108 ( 4) Move down at the same timing by the same height difference (H _a -H _b ). Thus, when the rear end of the substrate G passes just below the resist nozzle 82 in the coating region M ₃ , the front end of the substrate G is stably and reliably set by the rigid restraining force of the holding units 106 on the left and right in the rear row. It can be kept horizontal at the flying height _Hb . Thereby, the uniformity of the film thickness of the resist coating film RM formed on the rear end portion of the substrate G can be improved. When the rear end portion of the substrate G passes immediately below the resist nozzle 82, the front end of the substrate G is moving in the flying height H _c falls within out region M _5.

  In order to inspect or correct the level of each suction pad 108 (i) with respect to the resist nozzle 82, an optical distance sensor 166L (166R) attached to the nozzle support 142 of the nozzle lifting mechanism 132 can be used. . That is, as shown in FIG. 15, by moving the suction pad 108 (1) directly below the optical distance sensor 166L, the distance interval from the optical distance sensor 166L, that is, the distance interval J from the resist nozzle 82 is absorbed. It is possible to inspect whether each part on the upper surface of the pad 108 (1) is uniform. Further, the front and rear pad actuators 112a and 112b are controlled so that the distance interval J from the upper surface of the suction pad 108 (i) is equal at the position corresponding to the fulcrum of the front and rear pad support portions 110a and 110b. In this way, the suction pad 108 (1) can be leveled. Although only the suction pad 108 (1) on the left side of the front row is shown in FIG. 15, the same leveling inspection or correction is performed for the other suction pads 108 (2), 108 (3), 108 (4). Can do.

  Next, with reference to FIG. 9, FIG. 16, FIG. 17, the configuration and operation of the optical position sensor 130 provided in the holding unit 106 in this embodiment will be described. As described above, the optical position sensor 130 is used for measuring the height position of the resist nozzle 82 in place of the conventional dial gauge.

  As shown in FIG. 9, for example, the pad body of the suction pad 108 (1) on the left in the front row is extended in the transport direction (X direction), and the optical position sensor 130 is attached to the extension block 172. More specifically, the extension block 172 has a groove 174 formed at the center in the longitudinal direction so that the lower end of the resist nozzle 82a can enter and exit from above, and light is projected on both sides of the groove 174. A part 176 and a light receiving part 178 are arranged.

  As shown in FIG. 17, the light projecting unit 176 includes an optical fiber 182 that is optically coupled to a light emitting element 180 such as a light emitting diode or a laser diode, and the end face (outgoing surface) of the optical fiber 182. The light beam LB is emitted toward the light receiving unit 178 substantially horizontally at an angle parallel or oblique to the transport direction (X direction). The light receiving unit 178 has an optical fiber 186 that is optically coupled to a light receiving element (photoelectric conversion element) 184 such as a photodiode, for example, and the end surface (light receiving surface) of the optical fiber 186 is emitted from the light projecting unit 176. It faces the front and the front. The controller 170 drives the light emitting element 180 of the light projecting unit 176 to emit light and takes in an output signal from the light receiving element 184 of the light receiving unit 178 so that the light beam LB emitted from the light projecting unit 176 crosses the groove 174. Thus, it is possible to determine whether or not the light is incident on the light receiving surface of the light receiving unit 178, in other words, whether or not there is anything in the groove 174 that blocks the propagation of the light beam LB.

  In order to measure the height position of the resist nozzle 82 using the optical position sensor 130, first, the height position of the upper surface (reference) of the stage 80 is determined as shown in FIG. More specifically, a jig 186 as shown in the figure is placed on the stage 80, and the optical position sensor 130 reads the tip of the L-shaped probe 186a protruding from the stage 80 of the jig 186. That is, the optical position sensor 130 is slowly lifted from a position lower than the stage 80 by using the raising / lowering drive of the pad actuators (112a, 112b) and the pad support portions (110a, 110b) of the holding unit 106, and an L-shaped probe. The height position of the optical position sensor 130 when the tip of 186a blocks the light beam LB in the groove 174 is detected. This height position can be read using an encoder or a linear scale 124 provided in the holding unit 106. The tip of the L-shaped probe 186a may be set at a height position corresponding to the upper surface of the stage 80.

  Next, the jig 186 is removed from the stage 80, and instead, as shown in FIG. 17, the nozzle elevating mechanism 132 is operated to slowly lower the resist nozzle 82 from the reference height position for the coating process. At this time, as shown in the figure, the lower end (discharge port) of the resist nozzle 82 is positioned directly above the groove 174 of the optical position sensor 130. Thus, the height position of the resist nozzle 82 when the lower end (discharge port) of the resist nozzle 82 enters the groove 174 of the optical position sensor 130 and blocks the light beam LB is detected. This nozzle height position can be read using, for example, an encoder (EC) 188 provided in the motor 144L (144R) of the nozzle elevating unit 132. In this way, the distance interval (gap) between the reference height position for the coating process of the resist nozzle 82 and the stage 80 can be measured. If the gap measurement value is different from the set value, the reference height position of the resist nozzle 82 may be corrected so as to match.

  As described above, in the resist coating unit (COT) 44 of this embodiment, the height position of the resist nozzle 82 is set by the configuration in which the optical position sensor 130 is attached to the holding unit 106 of the substrate transport unit 84. Optical detection is simple and safe (without damaging the nozzle) and can be detected with high accuracy.

By measuring the distance between the substrate G on the stage 80 (particularly on the coating region M ₃ ) and the optical distance sensor 166L (166R) attached to the nozzle support 142 of the nozzle lifting mechanism 132. The gap S between the discharge port 82a of the resist nozzle 82 and the substrate G and the flying height _Hb can be measured from the distance measurement value. In this case, since the reference height position of the resist nozzle 82 can be inspected or corrected as needed, the reliability of the measurement function using the optical distance sensor 166L (166R) can be improved.

  16 and 17 show only the optical position sensor 130 provided integrally with the suction pad 108 (1) on the left side of the front row, but is provided integrally with the suction pad 108 (2) on the right side of the front row. The optical position sensor 130 can also perform the same nozzle height measurement as described above. Thereby, it is possible to adjust the parallelism of the nozzle outlets 82a by aligning the height positions of the left and right ends of the resist nozzle 82.

  In the above embodiment, the optical position sensor 130 is provided integrally with the left and right suction pads 108 (1) and 108 (2) in the front row, but is provided integrally with the left and right suction pads 108 (3) and 108 (4). It is also possible to have a structure or a structure provided integrally with any one of the four suction pads 108 (1) to 108 (2), or separate from the suction pad 108 (i) to provide pad support portions (110a, 110b). ) Or a structure attached to the pad actuator (112a, 112b). Furthermore, the optical position sensor 130 of the present invention can be provided in a holding unit capable of moving up and down to hold the substrate with a configuration or action different from that of the holding unit of the present invention.

  The substrate to be treated in the present invention is not limited to a glass substrate for LCD, and other flat panel display substrates, photomasks, printed substrates and the like are also possible. The processing liquid applied on the substrate is not limited to the resist liquid, and processing liquids such as an interlayer insulating material, a dielectric material, and a wiring material 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 process sequence in the said application | coating development processing system. It is a schematic plan view which shows the whole structure of the resist application unit in the embodiment. It is a perspective view which shows the whole structure of the said resist application unit. It is a schematic front view which shows the whole structure of the said resist application unit. 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 side view which shows the structure of the board | substrate conveyance part in the said resist application unit. It is an enlarged side view which shows the structure of the holding | maintenance part in the said board | substrate conveyance part. It is a perspective view which shows the structure of the holding | maintenance part in the said board | substrate conveyance part. It is a perspective view which shows one suitable structural example in which the pad support part supports a suction pad in the said holding | maintenance part. 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 block diagram which shows the main structures of the control system in the said resist application unit. It is a side view which shows a mode that a resist coating film is formed on a board | substrate in the said resist coating unit. It is a side view which shows the state of each part when a resist coating film is formed in the front-end part of a board | substrate in the said resist coating unit. It is a side view which shows one step of the method of performing the leveling test | inspection thru | or correction | amendment of a suction pad in the said resist application unit. It is a perspective view which shows the method to measure the height of a stage using the optical position sensor of embodiment in the said resist application unit. It is a perspective view which shows the method to measure the height position of a resist nozzle using the optical position sensor of embodiment in the said resist application unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Coating development processing system 30 Coating process part 44 Resist coating unit (COT)
80 Stage 82 Resist nozzle 82a Discharge port 84 Substrate transport unit 96 Resist liquid supply mechanism 104 Transport drive unit 106 Holding unit 108 (1) to 108 (4) Suction pad 110a, 110b Pad support unit 112a, 112b Pad actuator 130 Optical Position sensor 132 Nozzle lifting mechanism 170 Controller

Claims (15)

A stage for floating a rectangular substrate to be processed by gas pressure;
A holding unit that detachably holds the substrate in a floating state on the stage, and the holding unit that holds the substrate to float and convey the substrate in a predetermined conveyance direction on the stage. A transport unit that moves in the transport direction;
An elongated nozzle disposed above the stage, and from the nozzle toward the substrate that passes directly under the nozzle in the levitation conveyance to form a coating film of a processing solution on the substrate; A processing liquid supply section for discharging the processing liquid;
With
The holding portion is, possess a holding member that does not deflect substantially to locally hold the four corners of the substrate, and a lifting part for vertically moving or displacing the holding member,
The holding member regulates vertical displacement at two locations, each having four suction pads that can be sucked on the back surfaces of the four corners of the substrate, and each suction pad at a predetermined interval in the transport direction. And first and second pad support portions for supporting
Coating device. Both of the first and second pad support portions have a horizontal rotation shaft that allows the suction pad to be rotationally displaced in a vertical plane around the suction pad,
One of the first and second pad support portions has a linear motion shaft that allows the suction pad to be linearly displaced in the horizontal direction .
The coating apparatus according to claim 1 . The elevating part is
First and second actuators for independently raising and lowering the first and second pad support portions;
A lift control unit that comprehensively controls the driving operation of the first and second actuators ,
The coating apparatus of Claim 1 or Claim 2 . The first actuator includes a first motor and a first transmission mechanism that converts a rotational driving force of the first motor into a linear motion of the first pad support portion in a vertical direction,
The second actuator includes a second motor, and a second transmission mechanism that converts a rotational driving force of the second motor into a linear movement of the second pad support portion in a vertical direction .
The coating device according to claim 3. The elevating control unit includes first and second encoders for detecting rotation angles of the first and second motors, respectively, and controls the elevating movement distance of the first pad support unit. The output signal of the first encoder is used as a feedback signal to control the amount of rotation of the first motor, and the output signal of the second encoder is used as a feedback signal to control the vertical movement distance of the second pad support part. controlling the amount of rotation of the second motor as coating apparatus according to claim 4. The elevating control unit has first and second distance sensors for detecting the elevating movement distances of the first and second pad support parts, respectively, and the elevating movement distance of the first pad support part is determined. In order to control, the amount of rotation of the first motor is controlled using the output signal of the first distance sensor as a feedback signal, and the second distance is used to control the vertical movement distance of the second pad support part. The coating apparatus according to claim 4 , wherein the rotation amount of the second motor is controlled by using an output signal of the sensor as a feedback signal. The height position of the fulcrum of the suction pad is relatively set between the first and second pad support portions so that the height position of the nozzle with respect to the discharge port is uniform over the entire upper surface of each suction pad. The coating apparatus according to any one of claims 1 to 6 , further comprising a suction pad leveling adjustment unit that adjusts the pressure. The transport unit is
A pair of guide rails extending in the transport direction on both sides of the stage;
A slider mounted with the holding portion and movable along the guide rail;
A conveyance drive unit that drives the slider to travel straight along the guide rail,
Coating apparatus according to any one of claims 1-7. A nozzle lifting mechanism for moving the nozzle up and down;
The distance interval between the measurement object just below to measure optically, claim and an optical distance sensor attached to the nozzle support body for vertically moving together with supporting the nozzle or it 1-8 The coating apparatus as described in any one of these. To measure the distance interval between the substrate on the stage to the optical distance sensors, coating apparatus according to claim 9. A stage for floating a rectangular substrate to be processed by gas pressure;
A holding unit that detachably holds the substrate in a floating state on the stage, and the holding unit that holds the substrate to float and convey the substrate in a predetermined conveyance direction on the stage. A transport unit that moves in the transport direction;
An elongated nozzle disposed above the stage, and from the nozzle toward the substrate that passes directly under the nozzle in the levitation conveyance to form a coating film of a processing solution on the substrate; A processing liquid supply section for discharging the processing liquid;
A nozzle lifting mechanism for moving the nozzle up and down;
An optical distance sensor attached to the nozzle or a nozzle support that moves up and down integrally with the nozzle in order to optically measure the distance between the object to be measured directly below;
With
The holding part has a holding member that does not bend substantially holding the four corners of the substrate locally, and a lifting part for moving the holding member up and down or displacing the holding member,
Causing the optical distance sensor to measure a distance interval with the suction pad;
Coating device. A stage for floating a rectangular substrate to be processed by gas pressure;
A holding unit that detachably holds the substrate in a floating state on the stage, and the holding unit that holds the substrate to float and convey the substrate in a predetermined conveyance direction on the stage. A transport unit that moves in the transport direction;
An elongated nozzle disposed above the stage, and from the nozzle toward the substrate that passes directly under the nozzle in the levitation conveyance to form a coating film of a processing solution on the substrate; A processing liquid supply section for discharging the processing liquid;
With
The holding part has a holding member that does not bend substantially holding the four corners of the substrate locally, and a lifting part for moving the holding member up and down or displacing the holding member,
An optical position sensor for optically detecting the height position of the nozzle is attached to the holding portion.
Coating device. The optical position sensor is provided integrally with at least one of said suction pad, coating apparatus according to claim 12. The optical position sensor is provided on both left and right sides of the stage the conveying direction forward, coating apparatus according to claim 12. The optical position sensor is
A light projecting unit that emits a light beam substantially horizontally at an angle parallel or oblique to the transport direction;
Whether or not the lower end portion of the nozzle has a light receiving surface opposed to the light exit surface of the light projecting portion with a gap having a size that allows entry and exit from above, and whether or not the light beam reaches the light receiving surface. A light receiving section for generating an electrical signal representing ,
Coating apparatus according to any one of claims 12-14.

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