JP5016525B2 - Substrate processing method and substrate processing apparatus - Google Patents

Description

  The present invention provides a substrate in which a processing liquid is supplied to a substrate surface and a predetermined wet process is performed on the substrate surface, and then a low surface tension solvent is supplied to the substrate surface wetted with the processing liquid to replace the processing liquid. The present invention relates to a processing method and a substrate processing apparatus. The substrates to be processed include semiconductor wafers, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, FED (Field Emission Display) substrates, optical disk substrates, and magnetic disks. And a magneto-optical disk substrate.

  IPA (isopropyl alcohol: isopropyl alcohol: isopropyl alcohol, which has a lower surface tension than pure water) is one of the methods for removing the rinsing liquid adhering to the substrate surface after chemical liquid treatment with chemical liquid and rinse treatment with pure water or the like is performed. A treatment method using a liquid (low surface tension solvent) containing an organic solvent component such as alcohol) is known. For example, in Patent Document 1, after the pure water rinse process, the rotation speed of the substrate is reduced to the paddle process rotation speed and then the supply of pure water is stopped, and then an organic solvent such as IPA is supplied to the substrate to supply pure water. Is described, and further, the rotation speed of the substrate is increased to shake off the organic solvent and dry the substrate.

JP 2006-140285 A (FIGS. 4 and 5)

  In the technique described in Patent Document 1 described above, the low surface tension solvent is supplied from the center of the substrate while maintaining the substrate at the paddle processing rotation speed. The low surface tension solvent is a paddle-like liquid film formed by a rinsing liquid. A certain amount of time is required to exert the effect of diffusing into the inside and lowering its surface tension. In particular, when the substrate to be processed has a fine pattern formed on its surface, it takes a considerable amount of time (for example, 10 seconds or more) to spread the low surface tension solvent over the entire surface of the substrate. . During this time, if the supply of the low surface tension solvent is continued, the amount used will increase. Also, if the rotation speed of the substrate is increased too much so that the low surface tension solvent spreads quickly over the entire surface of the substrate, the rinse liquid may remain in the back of the pattern, or at the interface between the rinse liquid with a different surface tension and the low surface tension solvent. Problems such as exposure of the substrate surface may occur.

  The present invention has been made in view of the above problems. In a substrate processing method and a substrate processing apparatus for replacing a processing liquid on a substrate surface with a low surface tension solvent such as IPA, the processing liquid is used with a small amount of low surface tension solvent used. It aims at providing the technique which can be replaced efficiently and reliably.

  In order to achieve the above object, the substrate processing method according to the present invention includes a wet processing step of performing a wet processing on the substrate surface using a processing liquid while rotating a substantially horizontal substrate at a first speed, A paddle forming step of reducing the rotational speed of the substrate to a second speed to form a liquid film of the processing liquid on the substrate in a paddle shape, and a surface tension higher than that of the processing liquid while moving a supply position on the substrate; A first solvent supply step of supplying a low first low surface tension solvent to the liquid film on the substrate, and after the first solvent supply step, toward the center of the substrate than the treatment liquid A replacement step of replacing the liquid on the substrate with the second low surface tension solvent by increasing the rotational speed of the substrate while supplying a second low surface tension solvent having a low surface tension; The liquid on the substrate Was removed from the surface is characterized by comprising a drying step of drying the substrate surface.

  In the invention configured as described above, after the paddle-like liquid film is formed on the substrate by the processing liquid, the first low surface tension solvent is first supplied to the liquid film on the substrate while moving the supply position. Thereafter, the rotation speed of the substrate is increased while supplying the second low surface tension solvent to the center of the substrate. For this reason, the following effects can be obtained as compared with the conventional technique in which the low surface tension solvent is supplied only from the center of the substrate and is distributed over the entire substrate by centrifugal force.

  First, the time required to spread the low surface tension solvent over the entire substrate can be shortened. In order to maintain the paddle-like liquid film formed on the substrate, it is necessary to lower the rotational speed of the substrate and suppress the centrifugal force acting on the liquid film. However, the lower the rotational speed, the lower the surface tension. It takes time for the solvent to spread from the center of the substrate to the periphery. On the other hand, in the above invention, since the first low surface tension solvent is supplied while moving the supply position on the substrate, the first low surface tension solvent can be spread over the entire substrate surface in a shorter time. Is possible.

  In addition, the amount of low surface tension solvent used can be reduced. In the present invention, since the liquid on the substrate is later replaced by the second surface tension solvent, the first low surface tension solvent is added to the liquid film on the substrate to reduce the surface tension of the liquid film. A sufficient amount is sufficient, and it is not always necessary to completely replace the treatment liquid on the substrate with the first low surface tension solvent. Since the first low surface tension solvent can be distributed over the entire substrate in a short time as described above, the amount of the first low surface tension solvent used can be reduced. In addition, since the first low surface tension solvent is distributed in the liquid film, the subsequent replacement treatment with the second low surface tension solvent can be efficiently performed in a shorter time. The amount of solvent used can also be reduced.

  Furthermore, when the treatment liquid is replaced with a low surface tension solvent, exposure of the substrate surface that occurs near the interface between the two can be reliably prevented. When replacing the processing liquid by supplying a low surface tension solvent to the center of the substrate and spreading it to the periphery by centrifugal force, the surface of the substrate is exposed near the interface between the two because the low surface tension solvent and the processing liquid do not mix immediately. May end up. This problem is particularly noticeable when the rotational speed of the substrate is increased. In the present invention, since the first low surface tension solvent is added while changing the supply position before increasing the rotation speed of the substrate, the first low surface tension solvent is spread over the entire liquid film on the substrate. Therefore, the treatment liquid and the low surface tension solvent are mixed with each other, so that the interface between the two does not exist, and the exposure of the substrate surface as described above can be prevented. In addition, since the surface tension of the liquid film is reduced by adding the first low surface tension solvent, the liquid film is interrupted and the substrate is exposed when the replacement with the second low surface tension solvent is performed. Thus, the rotation speed of the substrate can be increased.

  In the substrate processing method configured as described above, in the first solvent supply step, the supply position may be moved from the center of the substrate toward the periphery. In this way, it is possible to more reliably prevent the liquid film from being interrupted from the center of the substrate and the surface being exposed. In addition, the first low surface tension solvent can be spread over the entire substrate in a shorter time in combination with the action of the centrifugal force.

  In the first solvent supply step, the substrate may be rotated at the second speed. By doing so, it is possible to maintain the paddle-like liquid film on the substrate and prevent the substrate surface from being exposed.

  Further, the first low surface tension solvent and the second low surface tension solvent may be the same. Thus, by using a common low surface tension solvent, the procurement and management of the solvent can be facilitated, and the supply mechanism can be simplified.

  Further, before the completion of the replacement step, an opposing member having an opposing surface that opposes almost the entire surface of the substrate may be disposed close to the substrate surface. In the replacement process, all of the liquid on the substrate is finally replaced with the second low surface tension solvent, but a large amount of mist such as processing liquid may be scattered in the ambient atmosphere of the substrate, and the open space above the substrate If this is left, mist may enter the liquid film on the substrate and contaminate the substrate. On the other hand, such a contamination can be prevented by ending the replacement step in a state where the opposing member is disposed opposite to the substrate.

  More specifically, for example, before the start of the replacement step, the facing member is disposed to face the substrate surface, and in the replacement step, the second low surface tension solvent is removed from a discharge port provided in the facing member. You may make it supply to the said substrate surface. By so doing, it is possible to supply the second low surface tension solvent to the substrate surface while the opposing member is disposed close to the substrate surface.

  As another method in the case where the first and second low surface tension solvents are the same, in the first solvent supply step, the nozzle disposed above the substrate is moved while moving the nozzle on the substrate. In the replacement step, the second low surface tension solvent may be supplied from the nozzle disposed above the center of the substrate. In this way, it is possible to perform processing with an apparatus having a simpler configuration by sharing a nozzle for supplying a low surface tension solvent.

  The second speed is preferably a speed at which the centrifugal force acting on the treatment liquid is smaller than the surface tension acting between the treatment liquid and the substrate surface. By setting the second speed in this way, a paddle-like liquid film can be reliably formed on the substrate surface by the processing liquid, and the low surface tension solvent can be used with the substrate surface covered with the liquid film in this way. By performing the replacement by, it is possible to prevent defects such as watermarks and spots due to exposure of the substrate surface. In addition, when a substrate having a pattern formed on the surface is a processing target, pattern collapse can be prevented.

  According to a first aspect of the substrate processing apparatus of the present invention, in order to achieve the above object, a substrate holding means for holding a substrate in a substantially horizontal posture, and a substrate held by the substrate holding means with a predetermined rotation axis. Substrate rotating means for rotating around, processing liquid supply means for supplying a processing liquid for performing wet processing on the substrate to the substrate surface held by the substrate holding means, and a supply position on the substrate surface. A first solvent supply means for supplying a first low surface tension solvent having a surface tension lower than that of the processing liquid to the substrate surface while being moved, and a surface tension lower than that of the processing liquid at the center of the substrate surface A second solvent supply means for supplying a second low surface tension solvent; and a control means for controlling the substrate rotating means, the first solvent supply means and the second solvent supply means, and the control means. The substrate A rotating film is used to reduce the rotational speed of the substrate after the wet processing to form a liquid film of the processing liquid on the substrate in a paddle shape. Then, the liquid film is supplied from the first solvent supply unit to the liquid film. The first low surface tension solvent is supplied, and after the supply is finished, the second low surface tension solvent is supplied from the second solvent supply means, and the rotation speed of the substrate is increased by the substrate rotation means. It is characterized by letting.

  In the invention configured as described above, as in the case of the substrate processing method described above, after the paddle-like liquid film is formed on the substrate by the processing liquid, the first low surface tension solvent is first moved while moving the supply position. Is supplied to the liquid film on the substrate, and then the rotation speed of the substrate is increased while supplying the second low surface tension solvent to the center of the substrate. For this reason, the same effect as the invention of the substrate processing method described above can be obtained.

  In the substrate processing apparatus configured as described above, a discharge port for discharging the second low surface tension solvent is provided at a substantially center of the counter surface, having a counter surface that faces the substantially entire surface of the substrate. You may comprise so that the provided opposing member may be further provided. By doing so, it is possible to prevent mist or the like in the processing atmosphere from adhering to the substrate surface or mixing into the liquid film.

  According to a second aspect of the substrate processing apparatus of the present invention, in order to achieve the above object, a substrate holding means for holding the substrate in a substantially horizontal posture, and a substrate held by the substrate holding means with a predetermined rotational axis. Substrate rotating means for rotating around, processing liquid supply means for supplying a processing liquid for performing wet processing on the substrate to the substrate surface held by the substrate holding means, and a supply position on the substrate surface. A solvent supply means configured to be movable and supplying a low surface tension solvent having a surface tension lower than that of the processing liquid to the substrate surface; and a control means for controlling the substrate rotation means and the solvent supply means, The control means forms a liquid film of the processing liquid on the substrate in a paddle shape by decelerating the rotation speed of the substrate after the wet processing by the substrate rotating means. The low surface tension solvent is supplied from the solvent supply means while moving the supply position, and after the supply is completed, the supply position is fixed at the center of the substrate surface, and the low surface tension solvent is supplied from the solvent supply means. The rotation speed of the substrate is increased by the substrate rotation means while being supplied.

  In the invention configured as described above, after a paddle-like liquid film is formed on the substrate by the processing liquid, the low surface tension solvent is first supplied to the liquid film on the substrate while moving the supply position, and then In addition, the rotation speed of the substrate is increased while supplying a low surface tension solvent to the center of the substrate. Therefore, also in this invention, the same effect as that of the above-described substrate processing method can be obtained.

  In addition, as the “first and second low surface tension solvents” used in the present invention, a 100% organic solvent component or a mixed solution thereof with pure water can be used. Moreover, it may replace with the solvent containing an organic solvent component as a low surface tension solvent, and may use the solvent which essentially contains surfactant. Here, an alcohol-based organic solvent can be used as the “organic solvent component”. As the alcohol-based organic solvent, isopropyl alcohol, ethyl alcohol, or methyl alcohol can be used from the viewpoints of safety, cost, and the like, and isopropyl alcohol (IPA) is particularly preferable.

  According to the present invention, after the liquid film of the processing liquid on the paddle is formed on the substrate, the low surface tension solvent (first low surface tension solvent) is supplied to the liquid film on the substrate while moving the supply position. Thus, the low surface tension solvent is spread over the entire substrate, and then the rotation speed of the substrate is increased while supplying the low surface tension solvent (second low surface tension solvent) to the center of the substrate. Therefore, the processing liquid on the substrate can be efficiently replaced with a low surface tension solvent with a small amount of use in a short time, and exposure of the substrate surface at that time can be prevented. In addition, by drying the substrate replaced with the low surface tension solvent in this way, the substrate can be dried without generating defects such as watermarks, spots, and pattern collapse.

  FIG. 1 is a diagram showing a first embodiment of a substrate processing apparatus according to the present invention. FIG. 2 is a block diagram showing a main control configuration of the substrate processing apparatus of FIG. This substrate processing apparatus is a single-wafer type substrate processing apparatus used for a cleaning process for removing unnecessary substances adhering to a surface Wf of a substrate W such as a semiconductor wafer. More specifically, the substrate surface Wf was wetted with a rinsing solution after being subjected to a chemical treatment with a chemical solution such as hydrofluoric acid and a rinsing treatment with pure water or DIW (deionized water). An apparatus for drying the substrate surface Wf. In this embodiment, the substrate surface Wf means a pattern formation surface on which a device pattern made of poly-Si or the like is formed.

  The substrate processing apparatus includes a spin chuck 1 that rotates while holding the substrate W in a substantially horizontal posture with the substrate surface Wf facing upward, and a chemical solution toward the surface Wf of the substrate W held by the spin chuck 1. A chemical solution discharge nozzle 3 for discharging, and a blocking member 9 arranged at a position above the spin chuck 1 are provided.

  The spin chuck 1 has a rotation support shaft 11 connected to a rotation shaft of a chuck rotation mechanism 13 including a motor, and can rotate about a rotation axis J (vertical axis) by driving the chuck rotation mechanism 13. The rotating support shaft 11 and the chuck rotating mechanism 13 are accommodated in a cylindrical casing 2. A disc-shaped spin base 15 is integrally connected to the upper end portion of the rotation spindle 11 by a fastening component such as a screw. Therefore, the spin base 15 rotates around the rotation axis J by driving the chuck rotation mechanism 13 in accordance with an operation command from the control unit 4 that controls the entire apparatus. Thus, in this embodiment, the chuck rotating mechanism 13 functions as the “substrate rotating means” of the present invention. Further, the control unit 4 controls the chuck rotation mechanism 13 to adjust the rotation speed.

  Near the peripheral edge of the spin base 15, a plurality of chuck pins 17 for holding the peripheral edge of the substrate W are provided upright. Three or more chuck pins 17 may be provided to securely hold the circular substrate W, and are arranged at equiangular intervals along the peripheral edge of the spin base 15. Each of the chuck pins 17 includes a substrate support portion that supports the peripheral portion of the substrate W from below, and a substrate holding portion that holds the substrate W by pressing the outer peripheral end surface of the substrate W supported by the substrate support portion. Yes. Each chuck pin 17 is configured to be switchable between a pressing state in which the substrate holding portion presses the outer peripheral end surface of the substrate W and a released state in which the substrate holding portion is separated from the outer peripheral end surface of the substrate W.

  When the substrate W is delivered to the spin base 15, the plurality of chuck pins 17 are released, and when the substrate W is cleaned, the plurality of chuck pins 17 are pressed. To do. By setting the pressed state, the plurality of chuck pins 17 can grip the peripheral edge of the substrate W and hold the substrate W in a substantially horizontal posture at a predetermined interval from the spin base 15. As a result, the substrate W is supported with its front surface (pattern forming surface) Wf facing upward and the back surface Wb facing downward. Thus, in this embodiment, the chuck pin 17 functions as the “substrate holding means” of the present invention. The substrate holding means is not limited to the chuck pins 17, and a vacuum chuck that supports the substrate W by sucking the substrate back surface Wb may be used.

  The chemical liquid discharge nozzle 3 is connected to a chemical liquid supply source via a chemical valve 31. For this reason, when the chemical liquid valve 31 is opened and closed based on the control command from the control unit 4, the chemical liquid is pumped from the chemical liquid supply source toward the chemical liquid discharge nozzle 3, and the chemical liquid is discharged from the chemical liquid discharge nozzle 3. Note that hydrofluoric acid or BHF (buffered hydrofluoric acid) or the like is used as the chemical solution. Further, a nozzle moving mechanism 33 (FIG. 2) is connected to the chemical liquid discharge nozzle 3, and the chemical liquid discharge nozzle 3 is moved to the substrate W by driving the nozzle moving mechanism 33 in accordance with an operation command from the control unit 4. Can be reciprocated between the discharge position above the rotation center and the standby position retracted to the side from the discharge position.

  The blocking member 9 includes a plate-like member 90, a rotation support shaft 91 that is hollow inside, and supports the plate-like member 90, and an insertion shaft 95 that is inserted through the hollow portion of the rotation support shaft 91. ing. The plate-like member 90 is a disk-like member having an opening at the center, and is disposed to face the surface Wf of the substrate W held by the spin chuck 1. The plate-like member 90 has a lower surface (bottom surface) 90 a that is a substrate facing surface that faces the substrate surface Wf substantially in parallel, and the planar size of the plate member 90 is equal to or larger than the diameter of the substrate W. The plate-like member 90 is attached substantially horizontally to the lower end portion of the rotation support shaft 91 having a substantially cylindrical shape, and the rotation support shaft 91 is rotatable about a rotation axis J passing through the center of the substrate W by an arm 92 extending in the horizontal direction. Is retained. A bearing (not shown) is interposed between the outer peripheral surface of the insertion shaft 95 and the inner peripheral surface of the rotation support shaft 91. A blocking member rotating mechanism 93 and a blocking member lifting mechanism 94 are connected to the arm 92.

  The blocking member rotation mechanism 93 rotates the rotation support shaft 91 around the rotation axis J in response to an operation command from the control unit 4. When the rotation support shaft 91 is rotated, the plate member 90 rotates integrally with the rotation support shaft 91. The blocking member rotating mechanism 93 is configured to rotate the plate-like member 90 (lower surface 90a) in the same rotational direction as the substrate W and at substantially the same rotational speed in accordance with the rotation of the substrate W held by the spin chuck 1. Yes.

  Further, the blocking member elevating mechanism 94 can make the blocking member 9 close to and opposite to the spin base 15 according to an operation command from the control unit 4, or can be separated from the spin base 15. Specifically, the control unit 4 operates the blocking member elevating mechanism 94 to raise the blocking member 9 to a separation position above the spin chuck 1 when the substrate processing apparatus carries the substrate W in and out. Let On the other hand, when a predetermined process is performed on the substrate W, a predetermined facing position set in the vicinity of the surface Wf of the substrate W held by the spin chuck 1 as required (shown in FIG. 1). The blocking member 9 is lowered to the position). Thus, in this embodiment, the blocking member 90 functions as the “facing member” of the present invention, and the substrate facing surface 90a of the blocking member 90 corresponds to the “facing surface” of the present invention.

  FIG. 3 is a longitudinal sectional view showing the main part of the blocking member provided in the substrate processing apparatus of FIG. 4 is a cross-sectional view (cross-sectional view) taken along the line A-A ′ of FIG. An insertion shaft 95 inserted in the hollow portion of the rotation support shaft 91 has a circular cross section. This is to make the gaps between the insertion shaft 95 (non-rotating side member) and the rotation support shaft 91 (rotating side member) uniform over the entire circumference. The gap between the insertion shaft 95 and the rotation support shaft 91 is sealed from the outside. Three fluid supply paths are formed in the insertion shaft 95 so as to extend in the vertical axis direction. That is, a rinse liquid supply path 96 serving as a rinse liquid path, a solvent supply path 97 serving as a path for a low surface tension solvent having an organic solvent component that dissolves in the rinse liquid and lowers the surface tension, and an inert gas such as nitrogen gas A gas supply path 98 serving as a passage is formed in the insertion shaft 95. The rinsing liquid supply path 96, the solvent supply path 97, and the gas supply path 98 are respectively connected to an interpolating shaft 95 made of PTFE (polytetrafluoroethylene) with PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin). Tetrafluoroethylene and perfluoroalkylvinylether) tubes 96b, 97b, 98b are inserted in the axial direction.

  Then, the lower ends of the rinse liquid supply path 96, the solvent supply path 97, and the gas supply path 98 become the rinse liquid discharge port 96a, the solvent discharge port 97a, and the gas discharge port 98a, respectively, of the substrate W held on the spin chuck 1. Opposite the surface Wf. In this embodiment, the diameter of the insertion shaft is 18 to 20 mm. Moreover, the diameters of the rinse liquid discharge port 96a, the solvent discharge port 97a, and the gas discharge port 98a are formed to 4 mm, 1 to 2 mm, and 4 mm, respectively. Thus, in this embodiment, the diameter of the solvent discharge port 97a is smaller than the diameter of the rinse liquid discharge port 96a. Thereby, the trouble shown below can be prevented. That is, the surface tension of the low surface tension solvent is lower than that of the rinse liquid (DIW). For this reason, when low surface tension solvent is discharged from the solvent discharge port having the same diameter as that for rinsing liquid discharge, the low surface tension solvent is discharged from the solvent discharge port after the discharge of the low surface tension solvent is stopped. There is a risk of falling. On the other hand, when the rinse liquid is discharged from the rinse liquid discharge port having the same diameter as that formed for solvent discharge, the discharge speed of the rinse liquid is increased. As a result, the rinse liquid (DIW), which is an electrical insulator, may collide with the substrate surface Wf at a relatively high speed, so that the supply portion of the substrate surface Wf to which the rinse liquid is directly supplied may be charged and oxidized. is there.

  In contrast, in this embodiment, the discharge port for the low surface tension solvent and the rinse liquid are provided separately, and the diameter of the solvent discharge port 97a is smaller than the diameter of the rinse liquid discharge port 96a. For this reason, it is possible to prevent the low surface tension solvent from dropping from the solvent discharge port, to suppress an increase in the discharge speed of the rinse liquid from the rinse liquid discharge port, and to suppress oxidation due to charging of the substrate surface Wf. it can.

  In this embodiment, the rinse liquid discharge port 96a is provided at a position shifted radially outward from the central axis of the blocking member 9, that is, the rotation axis J of the substrate W. Thereby, it is avoided that the rinse liquid discharged from the rinse liquid discharge port 96a is concentrated and supplied to one point (the rotation center W0 of the substrate W) of the substrate surface Wf. As a result, charged portions on the substrate surface Wf can be dispersed, and oxidation due to charging of the substrate W can be reduced. On the other hand, if the rinse liquid discharge port 96a is too far from the rotation axis J, it is difficult to make the rinse liquid reach the rotation center W0 on the substrate surface Wf. Therefore, in this embodiment, the distance L from the rotation axis J in the horizontal direction to the rinse liquid discharge port 96a (discharge port center) is set to about 4 mm. Here, the upper limit of the distance L at which the rinse liquid (DIW) can be supplied to the rotation center W0 on the substrate surface Wf is 20 mm under the following conditions.

Flow rate of DIW: 2L / min
Substrate rotation speed: 1500rpm
The state of the substrate surface: the center of the surface is a hydrophobic surface. Also, the upper limit value of the distance from the rotation axis J to the solvent discharge port 97a (discharge port center) is as long as the rotation speed of the substrate is set to 1500 rpm. Is basically the same as the upper limit (20 mm) of the distance L from the rinsing liquid discharge port 96a (discharge port center).

  On the other hand, with respect to the distance from the rotation axis J to the gas discharge port 98a (discharge port center), a gap space formed between the blocking member 9 (plate member 90) positioned at the opposing position and the substrate surface Wf. As long as nitrogen gas can be supplied to SP, it is not particularly limited and is optional. However, from the viewpoint of blowing nitrogen gas onto a solvent layer made of a low surface tension solvent formed on the substrate surface Wf as described later and discharging the solvent layer from the substrate W, the gas discharge port 98a has a rotational axis J. It is preferable to provide at the top or in the vicinity thereof.

  A space portion formed between the inner wall surface of the rotation support shaft 91 and the outer wall surface of the insertion shaft 95 constitutes the outer gas supply path 99, and the lower end of the outer gas supply path 99 is an annular outer gas. The discharge port 99a is formed. That is, the blocking member 9 includes an outer gas discharge port 99a in addition to a gas discharge port 98a for discharging nitrogen gas toward the center of the substrate surface Wf, and a rinse liquid discharge port 96a, a solvent discharge port 97a, and a gas discharge port. It is provided radially outward with respect to 98a and so as to surround the rinse liquid discharge port 96a, the solvent discharge port 97a, and the gas discharge port 98a. The opening area of the outer gas discharge port 99a is much larger than the opening area of the gas discharge port 98a. Thus, since two types of gas discharge ports are provided in the blocking member 9, nitrogen gas having different flow rates and flow rates can be discharged from the discharge ports. For example, (1) In order to keep the atmosphere around the substrate surface Wf in an inert gas atmosphere, it is desirable to supply nitrogen gas at a relatively large flow rate and low speed so as not to blow off the liquid on the substrate surface Wf. On the other hand, (2) when removing the solvent layer of the low surface tension solvent on the substrate surface Wf from the substrate surface Wf, supply nitrogen gas to the center of the surface of the substrate W at a relatively small flow rate and at a high speed. Is desired. Therefore, in the case (1), nitrogen gas is mainly discharged from the outer gas discharge port 99a, and in the case (2), nitrogen gas is mainly discharged from the gas discharge port 98a. Nitrogen gas can be supplied toward the substrate surface Wf at an appropriate flow rate and flow rate depending on the use of the gas.

  Further, the tip (lower end) of the insertion shaft 95 is not flush with the lower surface 90a of the plate-like member 90, and is retracted upward from the same plane including the lower surface 90a (FIG. 3). According to such a configuration, it is possible to diffuse the nitrogen gas before the nitrogen gas discharged from the gas discharge port 98a reaches the substrate surface Wf and reduce the flow rate of the nitrogen gas to some extent. That is, if the flow rate of nitrogen gas from the gas discharge port 98a is too high, the nitrogen gas from the outer gas discharge port 99a interferes with each other and the solvent layer of the low surface tension solvent on the substrate surface Wf is discharged from the substrate W. It becomes difficult. As a result, droplets remain on the substrate surface Wf. On the other hand, according to the above configuration, the flow rate of nitrogen gas from the gas discharge port 98a is relaxed, and the solvent layer of the low surface tension solvent on the substrate surface Wf can be reliably discharged from the substrate W.

  Returning to FIG. 1, the description will be continued. The upper end portion of the rinsing liquid supply path 96 is connected to the rinsing liquid supply unit 8. The rinsing liquid supply unit 8 includes a rinsing liquid supply pipe 85 having one end connected to a DIW supply source (not shown) constituted by a factory utility or the like, and the other end of the rinsing liquid supply pipe 85 is the rinsing liquid. It is connected to the valve 83. The rinse liquid supply unit 8 having such a configuration can discharge DIW as a rinse liquid from the rinse liquid discharge port 96a when the rinse liquid valve 83 is opened. In this embodiment, DIW which is a rinsing liquid corresponds to the “processing liquid” of the present invention, and the rinsing liquid supply unit 8 functions as the “processing liquid supply means” of the present invention.

  The upper end of the solvent supply path 97 is connected to the solvent supply unit 7 that functions as the “first solvent supply means” of the present invention. The solvent supply unit 7 includes a cabinet unit 70 for generating a low surface tension solvent, and opens a solvent valve 762 inserted in a pipe 761 connecting the cabinet unit 70 and the solvent supply path 97, thereby opening the cabinet unit. The low surface tension solvent generated at 70 can be pumped to the solvent supply path 97. The solvent supply unit 7 further includes a pipe 763 branched on the upstream side of the solvent valve 762, a solvent discharge nozzle 765 connected thereto, and a solvent valve 764 provided on the pipe 763. By opening the solvent valve 764, the low surface tension solvent generated in the cabinet section 70 can be pumped to the solvent discharge nozzle 765, and the low surface tension solvent can be discharged from the nozzle. The solvent discharge nozzle 765 is connected to a nozzle moving mechanism 766 (FIG. 2), and can move in a direction substantially parallel to the surface of the substrate W, that is, in a substantially horizontal direction.

  As the organic solvent component constituting the low surface tension solvent, a substance that dissolves in DIW (surface tension: 72 mN / m) and lowers the surface tension, for example, isopropyl alcohol (surface tension: 21 to 23 mN / m) is used. The organic solvent component is not limited to isopropyl alcohol, and various organic solvent components such as ethyl alcohol and methyl alcohol may be used. The organic solvent component is not limited to a liquid, and various alcohol vapors may be dissolved in DIW as an organic solvent component to produce a low surface tension solvent.

  The cabinet unit 70 includes a storage tank 72 that stores a low surface tension solvent. One end of a DIW introduction pipe 73 for supplying DIW into the storage tank 72 is taken into the storage tank 72, and the other end is connected to a DIW supply source through an open / close valve 73a. Further, a flow meter 73b is interposed in the course of the DIW introduction pipe 73, and the flow meter 73b measures the flow rate of DIW introduced into the storage tank 72 from the DIW supply source. Based on the flow rate measured by the flow meter 73b, the control unit 4 controls the opening / closing valve 73a so that the flow rate of DIW flowing through the DIW introduction pipe 73 becomes a target flow rate (target value).

  Similarly, one end of the IPA introduction pipe 74 for supplying the IPA liquid into the storage tank 72 is taken into the storage tank 72, and the other end is connected to the IPA supply source via the opening / closing valve 74a. Yes. Further, a flow meter 74b is provided in the middle of the route of the IPA introduction pipe 74, and the flow meter 74b measures the flow rate of the IPA liquid introduced into the storage tank 72 from the IPA supply source. Then, the control unit 4 controls opening / closing of the opening / closing valve 74a based on the flow rate measured by the flow meter 74b so that the flow rate of the IPA liquid flowing through the IPA introduction pipe 74 becomes a target flow rate (target value).

  In this embodiment, the volume percentage of IPA in the low surface tension solvent (hereinafter referred to as “IPA concentration”) can be adjusted, that is, 100% IPA can be supplied as the low surface tension solvent, It is also possible to supply a mixed liquid in which DIW is mixed as a low surface tension solvent. When 100% IPA is always used as the low surface tension solvent, the IPA may be directly supplied via solvent valves 762 and 764 described below.

  The other end of the solvent supply pipe 75 whose one end is connected to the solvent supply path 97 is inserted into the storage tank 72, and the low surface tension solvent stored in the storage tank 72 is passed through the solvent valves 762 and 764. The supply path 97 and the solvent discharge nozzle 765 can be supplied. The solvent supply pipe 75 adjusts the temperature of the low surface tension solvent sent to the solvent supply pipe 75 by the metering pump 77 that feeds the low surface tension solvent stored in the storage tank 72 to the solvent supply pipe 75. And a filter 79 for removing foreign matter in the low surface tension solvent. Further, the solvent supply pipe 75 is provided with a concentration meter 80 for monitoring the IPA concentration.

  In addition, one end of a solvent circulation pipe 81 is branched and connected to the solvent supply pipe 75 between the solvent valves 762 and 764 and the concentration meter 80, while the other end of the solvent circulation pipe 81 is connected to the storage tank 72. Yes. A circulation valve 82 is interposed in the solvent circulation pipe 81. During the operation of the apparatus, the metering pump 77 and the temperature controller 78 are always driven, and while the low surface tension solvent is not supplied to the substrate W, the solvent valve 76 is closed and the circulation valve 82 is opened. As a result, the low surface tension solvent fed from the storage tank 72 by the metering pump 77 is returned to the storage tank 72 through the solvent circulation pipe 81. That is, while the low surface tension solvent is not supplied to the substrate W, the low surface tension solvent circulates in the circulation path including the storage tank 72, the solvent supply pipe 75, and the solvent circulation pipe 81. On the other hand, when it is time to supply the low surface tension solvent to the substrate W, the solvent valve 762 or 764 is opened while the circulation valve 82 is closed. Thereby, the low surface tension solvent sent out from the storage tank 72 is selectively supplied to the solvent supply path 97 or the solvent discharge nozzle 765. As described above, while the low surface tension solvent is not supplied to the substrate W, the low surface tension solvent is circulated so that the DIW and IPA are stirred and the DIW and IPA are sufficiently mixed. be able to. Further, after the opening of the solvent valves 762 and 764, the low surface tension solvent that is adjusted to a predetermined temperature and from which foreign matters are removed can be quickly supplied to the solvent supply path 97 or the solvent discharge nozzle 765.

  The upper ends of the gas supply path 98 and the outer gas supply path 99 are connected to the gas supply unit 18 (FIG. 2), respectively, and from the gas supply unit 18 to the gas supply path 98 and the outer side according to the operation command of the control unit 4. Nitrogen gas can be individually pumped to the gas supply path 99. Thus, nitrogen gas can be supplied to the gap space SP formed between the blocking member 9 (plate member 90) positioned at the opposing position and the substrate surface Wf. An inert gas other than nitrogen gas, for example, argon gas or low dew point air (dry air) may be supplied.

  A receiving member 21 is fixedly attached around the casing 2. Cylindrical partition members 23a, 23b, and 23c are erected on the receiving member 21. A space between the outer wall of the casing 2 and the inner wall of the partition member 23a forms the first drainage tank 25a, and a space between the outer wall of the partition member 23a and the inner wall of the partition member 23b serves as the second drainage tank 25b. The space between the outer wall of the partition member 23b and the inner wall of the partition member 23c forms the third drainage tank 25c.

  The bottoms of the first drain tank 25a, the second drain tank 25b, and the third drain tank 25c are formed with outlets 27a, 27b, 27c, respectively, and each outlet is connected to a different drain. ing. For example, in this embodiment, the first drainage tank 25a is a tank for collecting used chemical liquid and communicated with a recovery drain for collecting and reusing the chemical liquid. The second drainage tank 25b is a tank for draining the used rinse liquid, and communicates with a waste drain for disposal processing. Further, the third drainage tank 25c is a tank for draining the used low surface tension solvent, and communicates with a waste drain for disposal processing.

  A splash guard 6 is provided above the drainage tanks 25a to 25c. The splash guard 6 is provided so as to be movable up and down with respect to the rotation axis J of the spin chuck 1 so as to surround the periphery of the substrate W held in a horizontal posture on the spin chuck 1. The splash guard 6 has a shape that is substantially rotationally symmetric with respect to the rotation axis J, and includes three guards 61, 62, and 63 that are concentrically arranged with the spin chuck 1 from the radially inner side toward the outer side. ing. The three guards 61, 62, 63 are provided so that the height decreases in order from the outermost guard 63 toward the innermost guard 61, and the upper ends of the guards 61, 62, 63 are in the vertical direction. It arrange | positions so that it may be settled in the surface extended to.

  The splash guard 6 is connected to the guard lifting mechanism 65 and operates the lifting drive actuator (for example, an air cylinder) of the guard lifting mechanism 65 in accordance with an operation command from the control unit 4, so that the splash guard 6 is spin chucked. 1 can be moved up and down. In this embodiment, the splash guard 6 is moved up and down stepwise by driving the guard lifting mechanism 65, whereby the processing liquid scattered from the rotating substrate W is separated into the first to third drain tanks 25a to 25c and drained. It is possible to make it.

  On the upper part of the guard 61, a groove-shaped first guide portion 61a that is inwardly opened in a cross-sectional shape is formed. Then, by placing the splash guard 6 at the highest position (hereinafter referred to as “first height position”) during the chemical treatment, the chemical liquid scattered from the rotating substrate W is received by the first guide portion 61a, and the first discharge is performed. It is guided to the liquid tank 25a. Specifically, the chemical liquid splashing from the rotating substrate W is arranged by arranging the splash guard 6 so that the first guide portion 61a surrounds the periphery of the substrate W held by the spin chuck 1 as the first height position. Is guided to the first drainage tank 25 a through the guard 61.

  In addition, an inclined portion 62 a that is inclined obliquely upward from the radially outer side to the inner side is formed on the upper portion of the guard 62. Then, the rinsing liquid splashed from the rotating substrate W is received by the inclined portion 62a by positioning the splash guard 6 at a position lower than the first height position (hereinafter referred to as “second height position”) during the rinsing process. And guided to the third drainage tank 25b. Specifically, as the second height position, the splash guard 6 is arranged so that the inclined portion 62a surrounds the periphery of the substrate W held by the spin chuck 1, so that the rinsing liquid scattered from the rotating substrate W can be obtained. It passes between the upper end of the guard 61 and the upper end of the guard 62 and is guided to the second drainage tank 25b.

  Similarly, on the upper part of the guard 63, an inclined portion 63a that is inclined obliquely upward from the radially outer side to the inner side is formed. Then, by placing the splash guard 6 at a position lower than the second height position (hereinafter referred to as “third height position”) during the replacement process, the low surface tension solvent scattered from the rotating substrate W is inclined to the inclined portion 63a. And is guided to the second drainage tank 25c. Specifically, as the third height position, the splash guard 6 is disposed so that the inclined portion 63a surrounds the periphery of the substrate W held by the spin chuck 1, so that the low surface tension scattered from the rotating substrate W is obtained. The solvent passes between the upper end portion of the guard 62 and the upper end portion of the guard 63 and is guided to the third drainage tank 25c.

  Further, the substrate transfer means (not shown) is not moved by causing the spin chuck 1 to protrude from the upper end of the splash guard 6 at a position lower than the third height position (hereinafter referred to as “retraction position”). It is possible to place the processed substrate W on the spin chuck 1 and receive the processed substrate W from the spin chuck 1.

  Next, the operation of the substrate processing apparatus configured as described above will be described in detail with reference to FIGS. FIG. 5 is a flowchart showing the operation of the substrate processing apparatus. FIG. 6 is a schematic diagram showing the operation of the substrate processing apparatus of FIG.

  In this apparatus, a control unit 4 functioning as a “control unit” of the present invention controls each part of the apparatus according to a program stored in a memory (not shown), and a series of processes shown in FIG. Apply. That is, the control unit 4 positions the splash guard 6 at the retracted position and causes the spin chuck 1 to protrude from the upper end portion of the splash guard 6. In this state, when the unprocessed substrate W is carried into the apparatus by the substrate transport means (not shown), the substrate W is treated with a chemical solution, a rinse process, a paddle formation process, a solvent supply process, and a replacement process. And a cleaning process including each step of the drying process. A fine pattern made of, for example, poly-Si is formed on the substrate surface Wf. In this embodiment, the substrate W is carried into the apparatus with the substrate surface Wf facing upward and is held by the spin chuck 1 (step S101). The blocking member 9 is located at a position above the spin chuck 1 and prevents interference with the substrate W. Further, the chemical solution discharge nozzle 3 and the solvent discharge nozzle 765 are positioned at a retracted position outside the upper side of the substrate W as shown in FIG.

  After carrying in the substrate, the control unit 4 arranges the splash guard 6 at the first height position (position shown in FIG. 1) and executes the chemical treatment on the substrate W. That is, the chemical solution discharge nozzle 3 is moved to the discharge position, and the substrate W held by the spin chuck 1 is rotated at a predetermined rotation speed (for example, 800 rpm) determined within a range of 200 to 1200 rpm by driving the chuck rotation mechanism 13. (Step S102). Then, the chemical solution valve 31 is opened to supply hydrofluoric acid as a chemical solution from the chemical solution discharge nozzle 3 to the substrate surface Wf (HF supply). The hydrofluoric acid supplied to the substrate surface Wf is spread by centrifugal force, and the entire substrate surface Wf is treated with a chemical solution using hydrofluoric acid (step S103). The hydrofluoric acid shaken off from the substrate W is guided to the first drainage tank 25a and reused as appropriate.

  When the chemical processing is completed, the chemical discharge nozzle 3 is moved to the standby position. And the splash guard 6 is arrange | positioned in a 2nd height position, and the rinse process is performed with respect to the board | substrate W as "wet process" of this invention. That is, the rotation speed of the substrate W is set to the first speed, for example, 600 rpm (step S104), the rinse liquid valve 83 is opened, and the rinse liquid is discharged from the rinse liquid discharge port 96a of the blocking member 9 located at the separated position (step). S105; FIG. 6 (a); DIW supply). Simultaneously with the discharge of the rinsing liquid, the blocking member 9 is lowered toward the facing position and positioned at the facing position. As described above, the substrate surface Wf is kept wet by supplying the rinse liquid to the substrate surface Wf immediately after the chemical treatment. This is due to the following reason.

  That is, when hydrofluoric acid is shaken off from the substrate W after the chemical treatment, the substrate surface Wf begins to dry. As a result, the substrate surface Wf may be partially dried, and spots or the like may occur on the substrate surface Wf. Therefore, in order to prevent such partial drying of the substrate surface Wf, it is important to keep the substrate surface Wf wet. Further, nitrogen gas is discharged from the gas discharge port 98a and the outer gas discharge port 99a of the blocking member 9. Here, nitrogen gas is mainly discharged from the outer gas discharge port 99a. That is, the flow rate balance of the nitrogen gas discharged from both discharge ports is such that a relatively large flow rate of nitrogen gas is discharged from the outer gas discharge port 99a while the flow rate of the nitrogen gas discharged from the gas discharge port 98a is very small. Adjust.

  The rinse liquid supplied from the rinse liquid discharge port 96a to the substrate surface Wf is spread by the centrifugal force accompanying the rotation of the substrate W, and the entire substrate surface Wf is rinsed (wet processing step). That is, the hydrofluoric acid remaining on the substrate surface Wf is washed away by the rinse liquid corresponding to the treatment liquid of the present invention and removed from the substrate surface Wf. The used rinsing liquid shaken off from the substrate W is guided to the second drainage tank 25b and discarded. Further, the nitrogen gas is supplied to the gap space SP, so that the atmosphere around the substrate surface Wf is kept in a low oxygen concentration atmosphere. For this reason, the raise of the dissolved oxygen concentration of a rinse liquid can be suppressed.

  Further, when executing the above-described rinsing process and the process described later, the plate-like member 90 of the blocking member 9 is rotated in the same rotational direction as the substrate W and at substantially the same rotational speed. Thereby, it is possible to prevent a relative rotational speed difference from being generated between the lower surface 90a of the plate-like member 90 and the substrate surface Wf, and to suppress the occurrence of an entrained air current in the gap space SP. For this reason, it is possible to prevent the mist-like rinse liquid and the low surface tension solvent from entering the gap space SP and adhering to the substrate surface Wf. Further, by rotating the plate member 90, it is possible to shake off the rinsing liquid and the low surface tension solvent adhering to the lower surface 90a and prevent the rinsing liquid and the low surface tension solvent from staying on the lower surface 90a.

  When the rinsing process for a predetermined time is completed, a paddle forming process is executed next. That is, the control unit 4 decelerates the rotation speed of the substrate W to a second speed that is slower than the first speed (step S106). As a result, the rinse liquid discharged from the rinse liquid discharge port 96a is accumulated on the substrate surface Wf, and a DIW liquid film is formed in a paddle shape (paddle formation process; paddle formation process). In this embodiment, the control unit 4 sets the second speed to 10 rpm, continues supplying the rinse liquid for 9 seconds, then closes the rinse liquid valve 83 and discharges the rinse liquid from the rinse liquid discharge port 96a. Stop (step S107). As a result, a DIW liquid film is formed as shown in FIG. Although the second speed is not limited to 10 rpm, the second speed is within a range that satisfies the condition that the centrifugal force acting on the rinsing liquid is smaller than the surface tension acting between the rinsing liquid and the substrate surface Wf. Two speeds need to be set. This is because the above conditions must be satisfied in order to form a rinse liquid film in a paddle shape. The rotation speed of the substrate is maintained at the second speed until it is changed in a replacement process described later.

  Then, after the DIW supply is stopped, it waits for a predetermined time until the film thickness of the paddle-like DIW liquid film becomes substantially uniform over the entire surface of the substrate W, and the blocking member lifting mechanism 94 retracts the blocking member 9 upward. Let Thereafter, the solvent moving nozzle 765 is positioned above the center of the substrate surface Wf by the nozzle moving mechanism 766. Further, the control unit 4 arranges the splash guard 6 at the third height position and opens the solvent valve 764 to discharge the low surface tension solvent from the solvent discharge nozzle 765 (solvent supply process). The flow rate of IPA is set to a low flow rate of about 100 (mL / min), for example.

  The operation of the nozzle moving mechanism 766 causes the solvent discharge nozzle 765 to move horizontally along the direction Dn from the center of the substrate W toward the periphery while discharging IPA (FIG. 6C). Thus, IPA having an action of reducing the surface tension is added to the DIW liquid film formed on the substrate W (first solvent supply step). That is, in this embodiment, the IPA supply to the paddle-shaped DIW liquid film on the substrate W is performed by a so-called nozzle scan method in which IPA is supplied while changing the supply position by moving the nozzle on the substrate (step S108). ). When the solvent discharge nozzle 765 reaches the periphery of the substrate W, the solvent valve 764 is closed and the supply of IPA is stopped. However, the solvent discharge nozzle 765 is moved further outward and returned to the retracted position.

  Thus, by supplying IPA to the paddle-like DIW liquid film on the substrate W while changing the supply position on the substrate W, the amount of IPA used and the processing time can be reduced. The reason is as follows. In the conventional technique in which IPA is supplied only to the center of the substrate and spread outward by centrifugal force, the centrifugal force is weak at a rotational speed that can maintain a paddle-like liquid film on the substrate W, and the IPA is spread over the entire substrate. It takes a relatively long time. In the experiment by the present inventor, when the rotation speed of the substrate was 10 rpm, it took about 30 seconds to spread the IPA to the periphery of the substrate having a diameter of 300 mm. On the other hand, according to the nozzle scanning method, IPA can be distributed to the periphery of the substrate in about 5 to 10 seconds. Thus, in this embodiment, the time required to spread the IPA to the periphery of the substrate is shortened, and the amount of IPA used can be reduced accordingly. In this case, the liquid film on the substrate W is not necessarily completely replaced with IPA. However, in this embodiment, the replacement with the complete IPA is performed by continuously executing a replacement process described later. There is no problem because it is configured.

  Substitution processing is performed following solvent supply processing. That is, the blocking member 9 is disposed at a facing position close to the substrate W by the blocking member elevating mechanism 94 (step S109). At this time, as shown in FIG. 6D, the IPA spreads over the entire liquid film on the substrate W, and the liquid film is composed of a mixed liquid of DIW and IPA. In the liquid film in which DIW and IPA are mixed, the surface tension is smaller than that of DIW alone.

  In this state, the solvent valve 762 is opened, and IPA supply from the solvent supply port 97a is started (step S110). As a result, IPA is supplied from the center of the substrate W to the liquid film (DIW + IPA) on the substrate. As a result, as shown in FIG. 6E, the central portion of the liquid film (DIW + IPA) is replaced with IPA in the central portion of the surface of the substrate W, and a replacement region SR is formed in the liquid film. Thus, in this embodiment, the blocking member 9, particularly the solvent supply path 97 and the solvent supply port 97 a function as the “second solvent supply means” of the present invention.

  By continuing the supply of IPA from the solvent supply port 97a, the replacement region SR gradually expands to the outside of the substrate W. In order to further promote this, after the start of the supply of IPA or almost simultaneously, The control unit 4 accelerates the rotation of the substrate stepwise (step S111). In this embodiment, by accelerating the rotation speed of the substrate W in two stages (10 to 100 rpm, 100 to 300 rpm), the IPW is surely replaced with the IPA remaining in the back of the pattern formed on the substrate surface Wf. The pattern collapse on the substrate surface Wf due to the residual DIW can be reliably prevented. The used IPA shaken off from the substrate W is guided to the third drain tank 25c and discarded.

  In the replacement process, IPA is supplied to the center of the liquid film on the substrate W to which IPA has already been added, and the rotation speed of the substrate is increased. At this time, by adding IPA to the liquid film in advance, the surface tension of the liquid film is reduced, and even if the rotational speed is increased, there is little possibility that the liquid film is interrupted and the substrate surface Wf is exposed. It has become. In addition, since IPA is added to the liquid film in advance, the newly supplied IPA can immediately dissolve into the liquid film and is separated from each other at the interface between the liquid film and IPA. Exposure of the substrate surface Wf can also be prevented. Further, since the replacement process is performed in a state where the blocking member 9 is disposed close to the substrate W, the mist of the rinse liquid (DIW) is prevented from being dissolved into the liquid film on the substrate W, and the liquid film is finally In other words, it is completely replaced with only IPA (replacement step).

  Thus, when the replacement process is completed, the control unit 4 stops the supply of IPA (step S112), increases the rotation speed of the chuck rotation mechanism 13, and rotates the substrate W at a high speed (for example, 1000 rpm) (step S113). Thereby, the IPA adhering to the substrate surface Wf is shaken off, and the drying process (spin drying) of the substrate W is executed (drying process; drying process). At this time, since the low surface tension solvent has entered the gaps between the patterns, it is possible to prevent pattern collapse and the occurrence of watermarks. Further, since the gap space SP is filled with nitrogen gas supplied from the gas discharge port 98a and the outer gas discharge port 99a, the drying time is shortened and the liquid component (low surface tension solvent) adhering to the substrate W is reduced. The generation of watermarks can be more effectively suppressed by reducing the elution of the oxidizable substances. When the drying process of the substrate W is completed, the control unit 4 controls the chuck rotating mechanism 13 to stop the rotation of the substrate W. Then, the splash guard 6 is positioned at the retracted position, and the spin chuck 1 is protruded from above the splash guard 6. Thereafter, the substrate transfer means carries the processed substrate W out of the apparatus (step S114), and a series of cleaning processes for one substrate W is completed.

  As described above, in this embodiment, after rinsing with DIW, the rotational speed of the substrate W is reduced to form a paddle-like liquid film with a rinsing liquid (DIW), and while the nozzle is scanned over the liquid film, IPA is supplied to reduce the surface tension of the liquid film. Then, the IPA is supplied to the center of the substrate and the rotation speed of the substrate is increased to completely replace the liquid on the substrate with IPA, and the substrate is rotated by rotating the substrate at a high speed without supplying IPA. dry.

  Thus, prior to replacing the liquid on the substrate with IPA, IPA as a low surface tension solvent is spread over the entire liquid film on the substrate to reduce the surface tension. Particularly, since IPA is supplied to each part of the liquid film while moving the IPA supply position by scanning the nozzle, the IPA is spread over the entire substrate in a short time without separating DIW and IPA at the interface. Can be made. For this reason, it is possible to reduce the time required for processing and to keep the amount of IPA used low.

  In this way, by supplying IPA to the liquid film on the substrate in advance, in the subsequent replacement process by IPA, the rotation speed of the substrate is increased without causing the exposure of the substrate surface Wf at the interface between DIW and IPA. Thus, replacement can be performed efficiently in a short time. As a result, in this embodiment, the substrate can be satisfactorily dried in a short processing time and with a small amount of IPA used while preventing defects such as watermarks and pattern collapse.

  Further, by completing the replacement process with IPA in a state where the blocking member 9 is close to the substrate surface Wf, impurity components such as DIW and chemicals caused by mist are present in the liquid film on the substrate at the time of the replacement process. Mixing is prevented, and the quality of the substrate surface after drying can be improved.

  Next, a second embodiment of the substrate processing apparatus according to the present invention will be described. Since the configuration of the apparatus in the second embodiment can be the same as that of the first embodiment described above, the same components are denoted by the same reference numerals and the description thereof is omitted. However, the first embodiment is configured to discharge the IPA for replacement treatment from the solvent supply port 97a provided in the blocking member 9, whereas in the second embodiment, the blocking member 9 starts from the blocking member 9 as described later. Therefore, it is possible to omit the configuration for enabling this, that is, the solvent supply path 97, the solvent supply port 97a, the pipe 761, the open / close valve 762, and the like. Furthermore, the blocking member itself can be omitted.

  FIG. 7 is a flowchart showing the operation of the substrate processing apparatus of the second embodiment. The process from the loading of the substrate W into the apparatus to the solvent supply process (steps S101 to S108) for supplying IPA by the nozzle scanning method is the same as the process in the first embodiment. A number is attached and description is abbreviate | omitted.

  When the solvent discharge nozzle 765 reaches a position above the periphery of the substrate W by the nozzle scan, the nozzle moving mechanism 766 moves the solvent discharge nozzle 765 again above the center of the substrate (step S201). Whether or not IPA is discharged from the solvent discharge nozzle 765 during this movement is arbitrary, but here the discharge is continued. Then, the rotation speed of the substrate is increased to the third speed (step S202). The third speed can be set to 100 rpm, for example. If the IPA supply is stopped when the nozzle is moved in step S201, it is desirable to increase the rotation speed of the substrate after restarting the supply in order to prevent exposure of the substrate surface.

  Thus, after supplying the IPA to the center of the substrate by the solvent discharge nozzle 765 and rotating the substrate W for a predetermined time to completely replace the liquid on the substrate W with the IPA, the supply of IPA is stopped (step S203). After the nozzle 765 is retracted to the outside of the periphery of the substrate W (step S204), the blocking member 9 is brought close to the substrate surface Wf (step S205). Thereafter, the drying process and the substrate W are carried out as in the first embodiment (steps S113 and S114), and the process for one substrate is completed.

  FIG. 8 is a schematic view showing the operation of the substrate processing apparatus of the second embodiment. As shown in FIGS. 8A, 8B, and 8C, the first embodiment shown in FIGS. 6A to 6C is performed until the solvent supply process for supplying IPA while moving the solvent discharge nozzle 765. It is the same as the processing of the form. On the other hand, in the process of the second embodiment, as shown in FIG. 8D, the solvent discharge nozzle 765 that has moved to the periphery of the substrate is again disposed above the center of the substrate. At this time, the liquid film on the substrate W is formed by a liquid in which DIW and IPA are mixed. However, when IPA is newly supplied from the center, the replacement area is replaced by IPA in the central portion of the liquid film. SR occurs. Then, as the substrate rotates, the replacement region SR spreads outward, and finally the substrate surface Wf is covered with IPA as shown in FIG. A drying process is performed in this state.

  As described above, in this embodiment, after supplying the IPA to the DIW liquid film formed on the substrate W after the rinsing process while moving the solvent discharge nozzle 765, the solvent discharge nozzle 765 is moved above the center of the substrate. Move. Then, the substrate W is further rotated while supplying IPA from the nozzle 765. By doing this as well, the DIW liquid film on the substrate is replaced with IPA in a short time and with a small amount of IPA usage while preventing the exposure of the substrate surface Wf as in the first embodiment described above. Can do. In addition, since the same solvent discharge nozzle 765 is used for both the solvent supply process and the replacement process, the apparatus configuration can be simplified as compared with the first embodiment in which IPA is discharged from the blocking member 9. . Thus, in this embodiment, the solvent discharge nozzle 765 functions as the “solvent supply means” of the present invention.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, the substrate processing apparatus of each of the above embodiments includes the blocking member 9 disposed close to the substrate surface Wf, but the blocking member is not an essential configuration. In particular, as in the second embodiment, the supply of the solvent while moving the supply position and the subsequent supply of the solvent to the center of the substrate are performed with the same nozzle, or the nozzles for supplying each solvent are individually provided to shut off. The member can be omitted.

  In each of the above embodiments, the solvent discharge nozzle 765 is moved in one direction from the center of the substrate toward the peripheral edge so that the IPA spreads over the entire liquid film on the substrate W. However, the embodiment is not limited to this. For example, the solvent discharge nozzle 765 may be reciprocated or moved in a two-dimensional plane parallel to the substrate surface Wf. Further, IPA may be intermittently discharged from the solvent discharge nozzle 765.

  In the first and second embodiments, both the “first low surface tension solvent” and the “second low surface tension solvent” of the present invention are supplied from the same supply source (cabinet unit 70). However, as the first and second low surface tension solvents, low surface tension solvents having different components, or solvents containing the same components but having different composition ratios may be used.

  Alternatively, a mixed liquid of IPA and DIW may be prepared in the cabinet unit 70 and used as a low surface tension solvent. Moreover, the production | generation method of a liquid mixture is not limited to this. For example, an organic solvent component such as IPA may be mixed in-line on a liquid supply path for supplying DIW toward the liquid supply path (or nozzle) of the blocking member to generate a mixed liquid. Further, the liquid mixture generating means such as the cabinet section is not limited to being provided in the substrate processing apparatus, and the liquid mixture generated in another apparatus provided separately from the substrate processing apparatus is provided in the substrate processing apparatus. It may be supplied to the substrate surface Wf via a blocking member. Further, a solvent essentially containing a surfactant may be used instead of the solvent containing an organic solvent component such as IPA.

  In each of the above embodiments, DIW is used as the rinsing liquid. However, a liquid containing a component that does not have a chemical cleaning action on the substrate surface Wf such as carbonated water (DIW + CO2) is used as the rinsing liquid. Also good. In this case, a mixture of a liquid (carbonated water) having the same composition as the rinse liquid adhering to the substrate surface Wf and an organic solvent component may be used as the mixed liquid. Further, while carbonated water is used as the rinse liquid, the mixed liquid may be a mixture of DIW, which is the main component of carbonated water, and an organic solvent component. Further, while DIW is used as the rinsing liquid, the mixed liquid may be a mixture of carbonated water and an organic solvent component. In short, a mixture of a liquid adhering to the substrate surface Wf, a liquid having the same main component, and an organic solvent component may be used as the mixed liquid. In addition to DIW and carbonated water, hydrogen water, dilute concentration (for example, about 1 ppm) ammonia water, dilute hydrochloric acid, and the like can be used as the rinse liquid.

  In each of the above embodiments, the present invention is applied to a process of rinsing and drying a substrate after chemical treatment with hydrofluoric acid. However, the present invention is applied to processing on a substrate treated with another chemical solution. May be. However, the process of forming a paddle-like liquid film with a rinsing liquid on the substrate as in each of the above embodiments, substituting with a low surface tension solvent, and drying is performed after the hydrophobizing process, particularly for hydrophobizing the surface of the substrate. This is effective when the rinsing process is performed using a rinsing solution containing as a main component. By applying the present invention to such a process, a particularly remarkable effect can be obtained.

  The present invention relates to a semiconductor wafer, a glass substrate for photomask, a glass substrate for liquid crystal display, a glass substrate for plasma display, a substrate for FED (Field Emission Display), a substrate for optical disk, a substrate for magnetic disk, a substrate for magneto-optical disk, etc. The present invention can be applied to a substrate processing apparatus and a substrate processing method for performing a drying process on the entire surface of a substrate including the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the substrate processing apparatus concerning this invention. It is a block diagram which shows the main control structures of the substrate processing apparatus of FIG. It is a longitudinal cross-sectional view which shows the principal part of the interruption | blocking member with which the substrate processing apparatus of FIG. 1 was equipped. FIG. 4 is a cross-sectional view (cross-sectional view) taken along line A-A ′ of FIG. 3. It is a flowchart which shows operation | movement of a substrate processing apparatus. It is a schematic diagram which shows operation | movement of the substrate processing apparatus of FIG. It is a flowchart which shows operation | movement of the substrate processing apparatus of 2nd Embodiment. It is a schematic diagram which shows operation | movement of the substrate processing apparatus of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Spin chuck 4 ... Control unit (control means)
7 ... Solvent supply unit 8 ... Rinse solution supply unit (treatment solution supply means)
9: Blocking member (opposing member)
13 ... Chuck rotating mechanism (substrate rotating means)
17 ... chuck pin (substrate holding means)
97a ... Solvent supply port (second solvent supply means)
765 ... Solvent discharge nozzle (first solvent supply means, solvent supply means)
J: Rotating shaft SR ... Replacement area Wf ... Substrate surface W ... Substrate

Claims (11)

A wet processing step of performing wet processing on the substrate surface using a processing liquid while rotating the substrate in a substantially horizontal state at a first speed;
A paddle forming step of reducing the rotational speed of the substrate to a second speed and forming a liquid film of the processing liquid on the substrate in a paddle shape;
A first solvent supply step of supplying a first low surface tension solvent having a surface tension lower than that of the processing liquid to the liquid film on the substrate while moving a supply position on the substrate;
After the first solvent supply step, the liquid on the substrate is increased by increasing the rotation speed of the substrate while supplying a second low surface tension solvent having a lower surface tension than the processing liquid toward the center of the substrate. Replacing with a second low surface tension solvent;
A substrate processing method comprising: a drying step of removing the liquid on the substrate from the substrate surface after the replacing step and drying the substrate surface.   The substrate processing method according to claim 1, wherein in the first solvent supply step, the supply position is moved from the center of the substrate toward the periphery.   The substrate processing method according to claim 1, wherein, in the first solvent supply step, the substrate is rotated at the second speed.   The substrate processing method according to claim 1, wherein the first low surface tension solvent and the second low surface tension solvent are the same.   5. The substrate processing method according to claim 1, wherein an opposing member having an opposing surface that opposes substantially the entire surface of the substrate is disposed close to the substrate surface before the replacement step is completed. .   The counter member is disposed to face the substrate surface before the replacement step, and the second low surface tension solvent is supplied to the substrate surface from an ejection port provided in the counter member in the replacement step. 5. The substrate processing method according to 5. In the first solvent supply step, while the nozzle disposed above the substrate is moved on the substrate, the first low surface tension solvent is supplied from the nozzle,
The substrate processing method according to claim 4, wherein in the replacement step, the second low surface tension solvent is supplied from the nozzle disposed above the center of the substrate.   The substrate processing according to claim 1, wherein the second speed is a speed at which a centrifugal force acting on the treatment liquid is smaller than a surface tension acting between the treatment liquid and the substrate surface. Method. Substrate holding means for holding the substrate in a substantially horizontal posture;
Substrate rotating means for rotating the substrate held by the substrate holding means around a predetermined rotation axis;
A treatment liquid supply means for supplying a treatment liquid for subjecting the substrate to wet treatment on the substrate surface held by the substrate holding means;
First solvent supply means for supplying a first low surface tension solvent having a surface tension lower than that of the processing liquid to the substrate surface while moving a supply position on the substrate surface;
A second solvent supply means for supplying a second low surface tension solvent having a surface tension lower than that of the treatment liquid to the center of the substrate surface;
Control means for controlling the substrate rotation means, the first solvent supply means and the second solvent supply means,
The control means forms a liquid film of the processing liquid on the substrate in a paddle shape by reducing the rotation speed of the substrate after the wet processing by the substrate rotating means, and then The first low surface tension solvent is supplied from the first solvent supply means, and after the supply is finished, the second low surface tension solvent is supplied from the second solvent supply means and the substrate rotation means. A substrate processing apparatus for increasing a rotation speed of the substrate.   10. The apparatus according to claim 9, further comprising a facing member having a facing surface facing substantially the entire surface of the substrate surface and provided with a discharge port for discharging the second low surface tension solvent at a substantially center of the facing surface. The substrate processing apparatus as described. Substrate holding means for holding the substrate in a substantially horizontal posture;
Substrate rotating means for rotating the substrate held by the substrate holding means around a predetermined rotation axis;
A treatment liquid supply means for supplying a treatment liquid for subjecting the substrate to wet treatment on the substrate surface held by the substrate holding means;
A solvent supply means configured to move the supply position on the substrate surface and supplying a low surface tension solvent having a surface tension lower than that of the treatment liquid to the substrate surface;
Control means for controlling the substrate rotation means and the solvent supply means,
The control means forms a liquid film of the treatment liquid on the substrate in a paddle shape by decelerating the rotation speed of the substrate after the wet processing by the substrate rotating means. The low surface tension solvent is supplied from the solvent supply means while moving the supply position, and after the supply is completed, the supply position is fixed to the center of the substrate surface, and the low surface tension solvent is supplied from the solvent supply means. And a rotation speed of the substrate is increased by the substrate rotating means.

Images