JP2010238780A - Substrate treatment apparatus and substrate treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment apparatus that can treat a substrate by a treatment liquid while holding an extremely thin liquid film of the treatment liquid on the upper surface of the substrate. <P>SOLUTION: An opposing rod 14 is arranged on the upper surface of a wafer W held by a spin chuck 2. The opposing rod 14 is supported by the supporting bracket of an arm 15 in a vertically movable manner. When the opposing rod 14 is made adjacent to the upper surface of the wafer W rotated by the spin chuck 2 and brought into contact with the liquid film of a chemical held by the upper surface of the wafer W, a lift force is given to the opposing rod 14 from the liquid film of the chemical and an estrangement direction force works on the opposing rod 14 in a vertically upward direction, so that the opposing rod 14 is relatively displaced in a vertically upward direction with respect to the supporting bracket of the arm 15. The opposing rod 14 is held at a position where the estrangement direction force is balanced with gravity working on the opposing rod 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a substrate processing apparatus and a substrate processing method for performing processing using a processing liquid on a substrate. Examples of substrates to be processed include semiconductor wafers, liquid crystal display substrates, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, and photomasks. For example.

  In the manufacturing process of a semiconductor device or a liquid crystal display device, a process using a processing liquid is performed on a substrate such as a semiconductor wafer or a glass substrate for a liquid crystal display panel. For example, a single-wafer type substrate processing apparatus that processes substrates one by one includes a spin chuck that rotates while holding the substrate in a horizontal posture, and a nozzle for supplying a processing liquid to the surface (surface to be processed) of the substrate And. The substrate is held by the spin chuck with its surface facing upward. Then, while the substrate is rotated by the spin chuck, the processing liquid is supplied from the nozzle to the center of the surface of the substrate. The processing liquid supplied to the surface of the substrate receives a centrifugal force due to the rotation of the substrate, and spreads on the surface of the substrate from the central portion toward the peripheral portion.

JP-A-8-78368

In order to ensure that the entire upper surface of the substrate is covered with the processing liquid, the flow rate of the processing liquid supplied to the substrate must be increased to some extent. Therefore, the amount of processing liquid required for processing one sheet increases, and the processing cost increases accordingly.
Therefore, as in the embodiment disclosed in Patent Document 1, while supplying the processing liquid to the upper surface of the substrate, a counter plate that covers the entire area of the upper surface is disposed to be opposed to the upper surface of the substrate. It is conceivable to hold a liquid film of the processing liquid between the member and the substrate surface. In this case, the processing liquid forming the liquid film spreads outward in the rotational radius direction through the counter plate and the substrate. As a result, the processing liquid spreads over the entire upper surface of the substrate, and a thin liquid film of the processing liquid can be held over the entire upper surface.

In order to suppress the flow rate of the processing liquid supplied to the substrate, it is desirable that the liquid film of the processing liquid formed on the upper surface of the substrate is as thin as possible. That is, it is desirable that the distance between the counter plate and the upper surface of the substrate be as small as possible.
However, since the substrate may swing in the vertical direction when the substrate is rotated, there is a limit value for the distance between the opposing plate and the substrate even if the opposing plate is brought close to the substrate. That is, there is a limit to the thickness of the liquid film of the processing liquid held on the upper surface of the substrate. Specifically, even if an attempt is made to maintain a gap of several millimeters of commas, the gap cannot be maintained because the substrate swings up and down. Further, as a result of the change in the gap, the thin liquid film between the counter plate and the upper surface of the substrate may be broken, and the state where the upper surface of the substrate is covered may not be maintained.

  Accordingly, an object of the present invention is to provide a substrate processing apparatus capable of reliably holding a thin liquid film of a processing solution on the upper surface of a substrate, thereby realizing high-quality substrate processing while reducing processing liquid consumption. It is to provide a substrate processing method.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided a substrate holding means (2) for holding the substrate (W) in a horizontal posture, and a substrate held by the substrate holding means around a vertical axis. Rotating means (4) for rotating, processing liquid supply means (3) for supplying a processing liquid to the upper surface of the substrate held by the substrate holding means, and an upper surface of the substrate held by the substrate holding means. A facing member (14) disposed to face the liquid film of the treatment liquid so as to receive lift from the liquid film with a distance (S) from the upper surface, and a support member for supporting the facing member (20) and a counter member holding mechanism (1; 100) including a counter member holding mechanism (44) that holds the counter member on the support member in a state in which the counter member can be relatively displaced along the vertical direction.

In addition, the alphanumeric characters in parentheses represent corresponding components in the embodiments described later. The same applies hereinafter.
According to this invention, the processing liquid is supplied to the upper surface of the substrate, and a liquid film of the processing liquid is formed on the upper surface. The liquid film of the processing liquid rotates as the substrate rotates. Therefore, in a state where the opposing member is in contact with the liquid film of the processing liquid, the opposing member is in contact with the relative flow of the processing liquid that forms the liquid film and pushes away the processing liquid that forms the liquid film. As the reaction, the opposing member receives lift from the liquid film of the processing liquid, that is, a force in a direction away from the upper surface of the substrate (separation direction force).

  The opposing member is held by the support member so as to be movable up and down. In response to the separation force caused by the contact between the liquid film of the processing liquid and the opposing member, the opposing member tends to be displaced upward relative to the support member. The separation direction force acting on the facing member, that is, the lift force that the facing member receives from the liquid film of the processing liquid increases as the facing member approaches the upper surface of the substrate. Therefore, the opposing member is held at a position where the force in the direction approaching the upper surface of the substrate such as gravity acting on the opposing member (approaching direction force) and the separation direction force acting on the opposing member are balanced. For this reason, the opposing member and the upper surface of the substrate can be opposed to each other with a very small interval. In addition, if the upper surface of the substrate swings up and down due to deformation of the substrate warp or the like, the opposing member also moves up and down accordingly, so the gap between the upper surface of the substrate and the opposing member does not depend on the vertical displacement of the upper surface of the substrate. Retained. Therefore, since the liquid film of the processing liquid is reliably held in the gap, the upper surface of the substrate can be reliably covered with the liquid film. Therefore, since a thin liquid film of the processing liquid can be reliably held on the upper surface of the substrate, the processing liquid can be spread over a wide area on the upper surface of the substrate while supplying the processing liquid at a small flow rate.

The invention according to claim 2 is the substrate processing apparatus according to claim 1, wherein the facing member holding mechanism includes an elastic body (45; 101) interposed between the support member and the facing member. .
According to this invention, the relative displacement of the opposing member with respect to the support member is allowed by the deformation of the elastic body. When the opposing member is relatively displaced upward with respect to the support member and the elastic body is deformed, the restoring force accompanying the deformation of the elastic body becomes an approaching direction force and acts on the opposing member. Thus, the configuration of the opposing member holding mechanism can be simplified by using the elastic body.

As the elastic body, a spring member such as a bellows, a coil spring, a leaf spring, or a disc spring can be used. The “bellows” refers to a bellows-like cylindrical body that can be elastically expanded and contracted.
According to a third aspect of the present invention, in the first or second aspect, the facing member has a rod-shaped substrate facing region (43) extending along the rotational radius direction of the substrate held by the substrate holding means. This is a substrate processing apparatus.

  According to this invention, the board | substrate opposing area | region of the opposing member is extended along the board | substrate rotation radial direction. On the other hand, the processing liquid supplied to the upper surface of the substrate moves toward the outside of the substrate along the rotation direction of the substrate as the substrate rotates. Therefore, the direction in which the substrate facing region of the counter member extends intersects with the direction of the flow of the processing liquid, and is orthogonal to the direction in which the substrate facing region of the counter member extends in the vector component of the force generated by the flow of the processing liquid. The force vector component has a predetermined value (not zero). Therefore, the opposing member receives lift from the liquid film of the processing liquid over a wide range in the longitudinal direction of the opposing member. Thereby, the stable separation direction force can be made to act on an opposing member.

According to a fourth aspect of the present invention, the counter member has a substrate counter region (43) extending from the rotation center of the substrate held by the substrate holding means to the peripheral edge of the substrate. It is a substrate processing apparatus as described in any one of these.
According to this invention, the board | substrate opposing area | region of the opposing member is extended from the rotation center of a board | substrate to the peripheral part of a board | substrate. Therefore, an extremely thin liquid film of the processing liquid can be held over the entire upper surface of the substrate by rotating the substrate.

According to a fifth aspect of the present invention, the substrate facing region has an inclined surface that faces the upper surface of the substrate held by the substrate holding means and moves away from the upper surface of the substrate as it goes upstream in the rotation direction of the substrate. The substrate processing apparatus according to claim 3, wherein the substrate processing apparatus is provided.
According to the present invention, as the substrate rotates, the facing member moves upstream in the rotation direction with respect to the liquid film on the upper surface of the substrate. Therefore, by forming an inclined surface in the substrate facing region that is separated from the upper surface of the substrate toward the upstream side in the rotation direction of the substrate, the liquid film of the processing liquid smoothly enters between the facing member and the upper surface of the substrate. Can be made.

  Further, the inclined surface is separated from the upper surface of the substrate as it goes upstream in the rotation direction of the substrate. Therefore, the opposing member receives a stable lift from the liquid film of the processing liquid when the opposing member contacts the liquid film of the processing liquid. Therefore, since the separating action force acting on the counter member can be stabilized, the gap between the counter member and the substrate can be further stabilized. The inclined surface may be a flat surface or a convex curved surface.

According to a sixth aspect of the present invention, the processing liquid supply means includes a nozzle (3) that discharges the processing liquid toward an upstream side of a region facing the facing member on the upper surface of the substrate held by the substrate holding means. It is a substrate processing apparatus as described in any one of Claims 1-5 containing.
According to the present invention, the processing liquid from the nozzle is supplied to the upper surface of the substrate upstream of the region where the facing member faces. Thereby, the processing liquid supplied to the upper surface of the substrate forms a liquid film between the opposing member and the substrate immediately after the supply. As a result, efficient substrate processing becomes possible.

  The invention described in claim 7 includes a substrate holding and rotating step of rotating the substrate (W) in a horizontal posture, a processing liquid supply step (S6) of supplying a processing liquid to the upper surface of the substrate, and relative to the vertical direction. The opposing member (14) held on the support member in a displaceable state is in contact with the liquid film of the processing liquid formed on the upper surface of the substrate and is spaced from the upper surface so as to receive lift from the liquid film. A substrate processing method including an opposing member arranging step (S5) arranged to face each other.

  According to the present invention, the same function and effect as those described in relation to the invention of claim 1 can be achieved.

1 is a diagram schematically showing a configuration of a substrate processing apparatus according to a first embodiment of the present invention. It is a top view which shows schematic structure of the substrate processing apparatus shown in FIG. It is sectional drawing which shows the structure of the front-end | tip part of an arm shown in FIG. FIG. 4 is a cross-sectional view taken along the section line IV-IV in FIG. 3. It is sectional drawing seen from the cut surface line VV of FIG. It is the figure which illustrated the mode at the time of the chemical | medical solution process in the substrate processing apparatus shown in FIG. FIG. 2 is a schematic plan view seen from above the wafer, showing a state where the counter bar shown in FIG. 1 is in a close position. It is process drawing which shows the process example of the substrate processing apparatus shown in FIG. It is a side view for demonstrating the mode of the process of FIG. It is an illustration sectional view showing the composition of the substrate processing device concerning a 2nd embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram schematically showing a configuration of a substrate processing apparatus 1 according to one embodiment (first embodiment) of the present invention. FIG. 2 is a plan view showing a schematic configuration of the substrate processing apparatus 1.
The substrate processing apparatus 1 is, for example, a single wafer type for processing a surface of a semiconductor wafer (hereinafter simply referred to as “wafer”) W as an example of a substrate with a processing solution (chemical solution and pure water (deionized water)). Device.

The substrate processing apparatus 1 is held by a spin chuck (substrate holding means) 2 that holds and rotates a wafer W in a horizontal posture in a processing chamber 80 partitioned by a partition wall (not shown), and the spin chuck 2. And a nozzle 3 for supplying a processing liquid to the upper surface (front surface) of the wafer W.
The spin chuck 2 includes a motor (rotating means) 4, a spin shaft 5 integrated with a drive shaft of the motor 4, a disc-shaped spin base 6 attached substantially horizontally to the upper end of the spin shaft 5, A plurality of clamping members 7 provided at substantially equal intervals at a plurality of locations on the peripheral edge of the spin base 6 are provided.

The wafer W can be held in a substantially horizontal posture by the plurality of holding members 7. When the motor 4 is driven in this state, the driving force causes the wafer W to rotate around the central axis of the spin shaft 5 while maintaining a substantially horizontal posture.
A chemical liquid supply pipe 8 and a pure water supply pipe 9 are connected to the nozzle 3. A chemical liquid flow rate adjustment valve 10 and a chemical liquid valve 11 are interposed in this order from the nozzle 3 side in the middle of the chemical liquid supply pipe 8. SC1 (ammonia hydrogen peroxide solution mixture), SC2 (hydrochloric acid hydrogen peroxide solution mixture), SPM (sulfuric acid / hydrogen peroxide mixture) as the chemical solution supplied to the chemical solution supply pipe 8 Hydrofluoric acid, buffered hydrofluoric acid (Buffered HF: liquid mixture of hydrofluoric acid and ammonium fluoride), hydrochloric acid, phosphoric acid, acetic acid, ammonia, aqueous hydrogen peroxide, citric acid, oxalic acid, TMAH, and the like can be exemplified. A pure water flow rate adjustment valve 12 and a pure water valve 13 are interposed in this order from the nozzle 3 side in the middle of the pure water supply pipe 9.

Accordingly, the chemical liquid from the chemical liquid supply source can be supplied to the nozzle 3 through the chemical liquid supply pipe 8 by closing the pure water valve 13 and opening the chemical liquid valve 11. Further, by closing the chemical liquid valve 11 and opening the pure water valve 13, pure water from a pure water supply source can be supplied to the nozzle 3 through the pure water supply pipe 9.
Further, a bar-shaped counter bar 14 as an example of a counter member is provided above the spin chuck 2. The counter bar 14 has a length that is half the diameter of the wafer W, and is attached to the tip of an arm 15 that extends horizontally above the spin chuck 2. A nozzle 3 is also attached to the tip of the arm 15. The arm 15 is supported by an arm support shaft 19 extending substantially vertically on the side of the spin chuck 2. Coupled to the arm support shaft 19 are an arm raising / lowering drive mechanism (see FIG. 1) 16 including a servo motor and a ball screw mechanism and an arm swing drive mechanism (see FIG. 1) 17 including a motor and the like. The arm swing drive mechanism 17 can swing the arm 15 in the horizontal plane about the axis set on the side of the spin chuck 2. As the arm 15 swings, the opposing rod 14 and the nozzle 3 move horizontally above the spin chuck 2. Further, the arm 15 can be moved up and down by the arm lifting drive mechanism 16. As the arm 15 moves up and down, the opposing bar 14 and the nozzle 3 move up and down. As described above, the arm raising / lowering drive mechanism 16 constitutes a contact / separation drive mechanism for causing the opposing rod 14 and the nozzle 3 to approach / separate from the wafer W.

  At the time of processing on the wafer W, the opposing bar 14 is arranged at a predetermined opposing position (upper position and proximity position, shown by a thick broken line in FIG. 2) facing the upper surface of the wafer W by swinging the arm 15. At this opposing position, the opposing rod 14 extends from the rotation center C of the wafer W to the peripheral edge along the rotational radius direction of the wafer W. In other words, the opposing bar 14 is adjacent to the rotation radius direction of the wafer W and extends in parallel with the rotation radius direction. Further, the nozzle 3 is disposed above the central portion of the wafer W when the counter rod 14 is in the counter position.

When the processing on the wafer W is not performed, the counter rod 14 and the nozzle 3 are arranged at a retracted position (shown by a two-dot chain line in FIG. 2) outside the rotation range of the wafer W.
In addition, the substrate processing apparatus 1 includes a control unit 18 configured with a microcomputer. The control unit 18 controls driving of the motor 4, the arm swing driving mechanism 17, and the arm lifting / lowering driving mechanism 16 according to a predetermined program. Further, the opening and closing of the chemical liquid valve 11 and the pure water valve 13 and the opening degree of the chemical liquid flow rate adjusting valve 10 and the pure water flow rate adjusting valve 12 are controlled.

FIG. 3 is a cross-sectional view showing the configuration of the distal end portion of the arm 15 and the opposing rod 14. 4 is a cross-sectional view taken along section line IV-IV in FIG. FIG. 5 is a cross-sectional view taken along the section line VV in FIG.
The arm 15 includes an arm main body 70 that extends in the horizontal direction, and an L-shaped support bracket (support member) 20 that is attached to the distal end portion of the arm main body 70 and supports the opposing rod 14. The support bracket 20 includes a vertical plate 22 in a vertical posture and a horizontal plate 23 extending in the horizontal direction from the lower end of the vertical plate 22. The upper end portion of the vertical plate 22 is fixed to the arm body 70. A first upper fixing plate 24 having a substantially square shape in plan view is fixed to the lower surface of the horizontal plate 23 by bolts 25. An upper through hole 26 penetrating in the vertical direction is formed in the central portion of the first upper fixing plate 24.

A thin plate-like nozzle support plate 27 for supporting the nozzle 3 (in this embodiment, an example in which two nozzles 3A and 3B are employed) is attached to the arm body 70. The nozzle support plate 27 has a vertical posture and is fixed to a side end surface of the support bracket 20.
The counter rod 14 includes a main body member 30 and a liquid contact member 31 that is attached to the lower portion of the main body member 30 and contacts a liquid film of the processing liquid held on the upper surface of the wafer W. The main body member 30 includes a long bar member 32 extending along the horizontal direction, and a head portion 33 extending upward from a central portion in the longitudinal direction of the bar member 32, and is integrally formed using PVC (polyvinyl chloride). Is formed.

  The head portion 33 has an upper end surface 34 that is a flat horizontal surface. The upper end surface 34 of the head portion 33 is formed with a recess 36 for accommodating a lower end portion of a guide 35, which will be described later, in the central portion in the longitudinal direction. The recess 36 extends in the vertical direction and has a predetermined depth. A ball bush 37 as a cylindrical linear motion bearing is fitted in the recess 36. A lateral bolt receiving recess 38 extending in the horizontal direction is formed on the side end surface of the head portion 33 (the left end surface shown in FIG. 3). A bolt hole 39 communicating with the recess 36 is formed at the bottom of the bolt receiving recess 38. The outer cylinder of the ball bush 37 is pressed against and fixed to the head portion 33 (opposing rod 14) by a bolt 49 screwed into the bolt hole 39. The head of the bolt 49 is housed in the bolt housing recess 38.

A lower fixing plate 40 having a substantially square shape in plan view is fixed to the upper surface of the head portion 33. A lower through hole 41 penetrating in the vertical direction is formed at the center of the lower fixing plate 40. The lower fixing plate 40 is fixed to the head portion 33 using bolts 42.
The liquid contact member 31 has a substantially rectangular cross section, and extends from one end of the main body member 30 to the other end along the longitudinal direction of the main body member 30. The liquid contact member 31 is formed with a smaller dimension in the width direction perpendicular to the longitudinal direction than the main body member 30. On the lower surface of the liquid contact member 31, a facing surface (substrate facing region) 43 is formed to face the upper surface of the wafer W held by the spin chuck 2. The opposing surface 43 is formed with a tapered surface that goes upward as it goes to one of the horizontal directions orthogonal to the longitudinal direction (the left direction shown in FIG. 4). The liquid contact member 31 is made of quartz, carbon, fluorine-based resin (PCTEF (polytrifluoroethylene chloride), PVDF (polyvinylidene fluoride), PTFT (polytetrafluoroethylene)) or the like in order to impart chemical resistance. Is formed.

The opposing bar 14 is held by the support bracket 20 via an opposing bar holding mechanism (opposing member holding mechanism) 44. The counter bar holding mechanism 44 includes a bar-shaped guide 35 extending in the vertical direction and a bellows 45 as an example of an elastic body surrounding the guide 35.
The upper end of the guide 35 is fixed to the lower surface of the horizontal plate 23. The upper end portion of the guide 35 is fixed to the horizontal plate 23 by a bolt 46. The lower end of the guide 35 is inserted into the ball bush 37. A lower end portion of the guide 35 is held by a ball bush 37 so as to be movable up and down. For this reason, the opposing bar 14 is allowed to move only in the vertical direction while being restricted from moving in the horizontal direction by the guide 35. The head of the bolt 46 is accommodated in an accommodation recess 48 formed at the center of the lower surface of the second upper fixing plate 47 that is fixed to the upper surface of the horizontal plate 23. A ball spline may be used in place of the guide 35 and the ball bush 37 as a configuration for holding the lower end portion of the guide 46 so as to be movable up and down relatively with respect to the opposing rod 14.

  The bellows 45 is formed using a resin material such as PTFE (polytetrafluoroethylene), and surrounds the guide 35. The upper end of the bellows 45 is fixed to the lower surface of the first upper fixing plate 24 so as to surround the upper through hole 26. Further, the lower end of the bellows 45 is fixed to the upper surface of the lower fixing plate 40 so as to surround the lower through hole 41.

  When the processing is not performed on the wafer W, that is, when the counter bar 14 is not close to the wafer W, the bellows 45 is in an extended state extended in the vertical direction by the gravity acting on the counter bar 14. ing. For this reason, when the opposing rod 14 is raised relative to the support bracket 20, the bellows 45 is compressed from the extended state, and the spring force acting on the opposing rod 14 is reduced. Thus, the opposing bar 14 is held by the support bracket 20 so as to be movable up and down by the guide 35 and the bellows 45 which are the opposing bar holding mechanism 44.

  The upper limit of the interval between the opposing bar 14 and the horizontal plate 23 is regulated by the interval regulating mechanism 50. The interval regulating mechanism 50 includes a U-shaped regulating bracket 51 (see FIG. 4). The restriction bracket 51 includes a vertical plate 52 that extends in the vertical direction, an upper surface plate 53 that is bent at the upper edge of the vertical plate 52 and extends in the horizontal direction, and a lower surface plate 54 that is bent at the lower edge of the vertical plate 52 and extends in the horizontal direction. And. The lower surface plate 54 is fixed to the upper surface of the lower fixing plate 40 with bolts 55. The upper surface plate 53 is formed with screw holes (not shown) penetrating the upper and lower surfaces thereof, and bolts 56 are screwed into the screw holes from above. When the tip of the bolt 56 abuts on the upper surface of the second upper fixing plate 47, the maximum distance between the opposing bar 14 and the horizontal plate 23 is regulated.

  The nozzle 3 includes a tubular first nozzle 3A and a tubular second nozzle 3B. The first nozzle 3A extends in the vertical direction and has a discharge port at the tip (lower end). The tip of the first nozzle 3 </ b> A reaches the vicinity of the liquid contact member 31. At the time of processing on the wafer W, the processing liquid from the discharge port of the first nozzle 3A is discharged vertically downward toward the supply position (see FIG. 7) near the rotation center on the upper surface of the wafer W. This supply position is located upstream of the facing region of the liquid contact member 31 on the upper surface of the wafer W.

  The second nozzle 3 </ b> B has a bent portion 57 that is bent into a substantially “<” shape when viewed from the side, and has a discharge port at the lower end of the bent portion 57. The tip (lower end) of the second nozzle 3 </ b> B reaches the vicinity of the liquid contact member 31. At the time of processing on the wafer W, the processing liquid from the second nozzle 3B is discharged from the upstream side in the rotation direction of the wafer W toward the supply position (see FIG. 7). The second nozzle 3B is fixed to a nozzle bracket 58 (see FIG. 5) attached to the nozzle support plate 27.

FIG. 6 is a schematic cross-sectional view showing a state of the substrate processing apparatus 1 during the chemical solution processing (a state when the counter rod 14 is in contact with the liquid film of the chemical solution).
During processing on the wafer W, the rotation of the spin chuck 2 rotates the wafer W while being held in a horizontal posture.
At the time of the chemical solution processing on the wafer W, the facing surface 43 of the liquid contact member 31 of the facing rod 14 is disposed to face a proximity position close to the surface of the wafer W. In this state, the facing surface 43 is inclined so as to be separated from the upper surface of the wafer W as it goes upstream in the rotation direction of the wafer W.

The chemical solution from the nozzle 3 is discharged toward a discharge position (refer to FIG. 7) on the upstream side of the upper surface of the wafer W with respect to the opposing region of the opposing rod 14. The chemical solution supplied to the upper surface of the wafer W receives a centrifugal force due to the rotation of the wafer W and spreads toward the peripheral edge of the wafer W.
The counter rod 14 disposed close to the upper surface of the wafer W is in contact with the chemical solution supplied on the wafer W. Due to the surface tension of the liquid film of the chemical solution on the wafer W, the chemical solution forming the liquid film spreads outward in the rotational radius direction along the counter rod 14. As a result, the chemical solution facing surface 43 is separated from the upper surface of the wafer W toward the upstream side in the rotation direction of the wafer W over the entire upper surface of the wafer W. It is possible to smoothly enter between the counter bar 14 and the upper surface of the wafer W.

  The liquid film of the chemical solution held on the upper surface of the wafer W rotates as the wafer W rotates. For this reason, in the state where the counter bar 14 is in contact with the liquid film of the chemical solution, the counter bar 14 moves relative to the liquid film and pushes away the liquid film. Therefore, the opposing rod 14 receives lift from the liquid film of the chemical solution. As a result, a force (separation direction force) in a direction away from the upper surface of the wafer W acts on the opposing rod 14.

Since the opposing surface 43 is separated from the upper surface of the wafer W as it goes upstream in the rotation direction of the wafer W, the opposing rod 14 receives a large lift from the liquid film. Therefore, a large separating action force can be applied to the opposing rod 14.
By this separation direction force, the opposing rod 14 is relatively displaced vertically upward with respect to the support bracket 20. The bellows 45 (see FIGS. 3 and 4) contracts in the vertical direction due to the relative displacement of the opposing rod 14, and the resistance against gravity (approaching direction force) acting on the opposing rod 14 and the like is not limited to the bellows 45 but the opposing rod 14 The state is also given by the lift received from the liquid film of the chemical solution. On the other hand, the separating force acting vertically upward on the counter bar 14 increases as the distance between the counter surface 43 of the counter bar 14 and the upper surface of the wafer W decreases. This is because, as the distance between the opposing bar 14 and the upper surface of the wafer W is narrower, the lifting force that the opposing bar 14 receives from the liquid film of the chemical solution increases. And the opposing bar | burr 14 is hold | maintained in the position where the separation direction force and the approach direction force balance. The material of the bellows 45 is selected so that the distance S between the opposing rod 14 and the upper surface of the wafer W is very small. As a result, a minute gap (for example, about 0.1 mm) can be reliably ensured between the counter bar 14 and the upper surface of the wafer W, and the counter bar 14 is separated from the counter bar 14 by such a small distance S. The upper surface of the wafer W can be arranged opposite to the wafer W.

FIG. 7 is a schematic plan view seen from above the wafer W, showing the state when the opposing bar 14 is in the proximity position.
When the counter bar 14 is in the proximity position, the counter surface 43 of the counter bar 14 extends from the rotation center C of the wafer W to the peripheral edge of the wafer W along the rotation radius direction of the wafer W.
The chemical solution supplied to the upper surface of the wafer W moves outward of the wafer W along with the rotation of the wafer W as the wafer W rotates. For this reason, the direction in which the facing surface 43 extends intersects the direction of the flow of the chemical solution. Therefore, the opposing rod 14 receives lift from the liquid film of the chemical liquid over the entire region in the longitudinal direction. Thereby, a large separation acting force can be applied to the opposing rod 14.

Further, since the opposing surface of the opposing rod 14 extends from the rotation center of the wafer W to the peripheral edge portion of the wafer W, the liquid film can be held over the entire upper surface of the wafer W by the rotation of the wafer W.
FIG. 8 is a process diagram showing a processing example of the substrate processing apparatus 1, and FIG. 9 is a side view for explaining the state of the processing of FIG.
The wafer W to be processed is loaded into the processing chamber 80 by a transfer robot (not shown) (step S1), and held by the spin chuck 2 with its surface facing upward. Further, the control unit 18 controls the arm swing drive mechanism 17 to swing the arm 15 (step S2). As the arm 15 swings, the nozzle 3 and the opposing rod 14 face the upper surface of the wafer W from the retracted position (shown by a two-dot chain line in FIG. 2) and are spaced apart from the upper surface to the upper surface. The position is moved to a position (shown by a solid line in FIG. 2; the position shown in FIG. 9A).

  After the wafer W is held on the spin chuck 2, the control unit 18 controls the motor 4 to start rotating the wafer W (step S3). When the rotation speed of the wafer W reaches a predetermined liquid processing speed (for example, 1500 rpm), the control unit 18 opens the chemical liquid valve 11 and discharges the chemical liquid from the nozzle 3. Prior to the discharge of the chemical liquid, the control unit 18 sets the opening of the chemical liquid flow rate adjustment valve 10 to a predetermined large opening, so that a high flow rate (for example, 2 L / min) of the chemical liquid is supplied from the chemical liquid supply pipe 8. It is sent to the nozzle 3. This large flow rate chemical is discharged from the nozzle 3 (step S4). The chemical solution discharged from the nozzle 3 is supplied to the central portion of the upper surface (front surface) of the wafer W, receives the centrifugal force due to the rotation of the wafer W, and spreads the upper surface of the wafer W toward the peripheral portion. Therefore, the entire upper surface of the wafer W is covered with the chemical solution (see FIG. 9A).

  When a predetermined large flow rate period (for example, 3 seconds) elapses from the start of the discharge of the chemical liquid, the control unit 18 controls the arm lifting drive mechanism 16 to lower the opposing rod 14 to the close position (see FIG. 6) (step S5). ). Moreover, the control part 18 switches the opening degree of the chemical | medical solution flow rate adjustment valve 10 to the predetermined small opening degree. Thereby, the discharge flow rate of the chemical solution discharged from the nozzle 3 becomes a small flow rate (for example, 0.5 L / min) (step S6; refer to FIG. 9B). At the same time, the control unit 18 controls the motor 4 to reduce the rotation speed of the wafer W to a predetermined speed (for example, 500 rpm).

In this state, as described above, the opposing rod 14 is held at a position where the separation direction force and the proximity direction force are balanced. As a result, the distance S between the upper surface of the wafer W and the opposing rod 14 is kept minute. Since the distance S is secured by the lift that the opposing bar 14 receives from the liquid film of the chemical solution, the wafer W and the opposing bar 14 do not contact even if the distance S is very small.
Even if the discharge flow rate of the chemical solution is the small flow rate or the rotation speed of the wafer W is low, the thickness of the liquid film of the chemical solution held on the upper surface of the wafer W is extremely small. The chemical solution can be spread over the entire upper surface of the. As a result, foreign matters such as particles adhering to the upper surface of the wafer W are physically removed from the entire upper surface of the wafer W.

  In this case, the rotation speed of the wafer W is reduced from a high speed (for example, 1500 rpm) to a low speed (for example, 500 rpm) during the chemical treatment, but the rotation speed of the wafer W is not changed during the process. (For example, a predetermined speed of 500 to 1500 rpm, preferably about 500 rpm). However, when decelerating in the middle of the chemical processing, the scattering speed of the chemical scattered from the wafer W is reduced, so that the chemical is prevented from being scattered around the wafer W, and the peripheral member of the wafer W is moved from the peripheral member to the surface of the wafer W. The rebound of the chemical solution can be suppressed.

  When a predetermined chemical solution processing time has elapsed from the start of the discharge of the chemical solution from the nozzle 3, the control unit 18 is set. The chemical liquid valve 11 is closed, and the discharge of the chemical liquid from the nozzle 3 is stopped (step S7). The control unit 18 opens the pure water valve 13 and discharges pure water from the nozzle 3 toward the center of the upper surface of the wafer W. Prior to the discharge of pure water, the control unit 18 sets the opening of the pure water flow rate adjusting valve 12 to a predetermined small opening, and therefore, a small flow rate (for example, 0.5 L / min from the pure water supply pipe 9). ) Pure water is sent to the nozzle 3. Accordingly, a small amount of pure water is discharged from the nozzle 3 (step S8). Thereby, the liquid film held on the upper surface of the wafer W is replaced from the chemical solution to pure water. And the chemical | medical solution adhering to the opposing rod 14 is washed away with this pure water.

When a predetermined small flow rate processing time (for example, 30 seconds) elapses from the start of pure water discharge, the control unit 18 controls the arm lifting drive mechanism 16 to raise the arm 15 (step S9). As the arm 15 is raised, the opposing rod 14 and the nozzle 3 are raised to the upper position (see FIG. 9A).
Further, the control unit 18 controls the opening degree of the pure water flow rate adjustment valve 12 so as to increase the discharge flow rate of the pure water amount from the nozzle 3 (for example, 2 L / min) (step S10). The pure water supplied to the upper surface of the wafer W flows toward the periphery of the wafer W under the centrifugal force due to the rotation of the wafer W, and the chemical solution adhering to the upper surface of the wafer W is washed away by the pure water.

Here, step S9 and step S10 may be interchanged. That is, the arm 15 may be raised after the discharge amount of pure water is set to a large flow rate first. In this case, it is possible to reliably prevent the liquid film of pure water on the wafer W from being interrupted (between step S9 and step S10).
When a predetermined pure water treatment time elapses from the start of pure water discharge, the control unit 18 closes the pure water valve 13 and stops the supply of pure water to the wafer W (step S11). Further, the control unit 18 accelerates the spin chuck 2 to a spin dry rotational speed (for example, about 2500 rpm). As a result, spin drying is performed in which the pure water adhering to the upper surface of the wafer W after being rinsed with pure water is spun off by a centrifugal force to be dried (step S12). When the spin dry is performed for a predetermined spin dry time, the rotation of the spin chuck 2 is stopped (step S13). Further, the arm 15 is swung, and the nozzle 3 and the opposing rod 14 are returned to the retracted position on the side of the spin chuck 2 (step S14). Thereafter, the wafer W is unloaded by a transfer robot (not shown) (step S15).

  As described above, according to this embodiment, the chemical liquid is supplied to the upper surface of the wafer W, and the liquid film of the chemical liquid is held on the upper surface. The liquid film of the chemical solution rotates as the wafer W rotates. Therefore, in a state where the opposing bar 14 is in contact with the liquid film of the chemical solution, the opposing bar 14 moves relative to the liquid film and pushes away the liquid film. Therefore, the opposing rod 14 receives lift from the liquid film of the chemical solution. As a result, a force (separation direction force) in a direction away from the upper surface of the wafer W acts on the opposing rod 14.

  The opposing bar 14 is held by the support bracket 20 so as to be movable up and down. In response to the separation force caused by the contact between the liquid film of the chemical solution and the counter bar 14, the counter bar 14 tends to be displaced upward relative to the support bracket 20. For this reason, the lift force that the counter bar 14 receives from the liquid film of the chemical solution increases as the counter bar 14 approaches the upper surface of the wafer W. For this reason, the separation direction force acting on the counter bar 14 also increases as the counter bar 14 approaches the upper surface of the wafer W. That is. Therefore, the opposing bar 14 is held at a position where the force in the direction approaching the upper surface of the wafer W (approaching direction force) such as gravity acting on the opposing bar 14 and the separating direction force acting on the opposing bar 14 are balanced. For this reason, the opposing rod 14 and the upper surface of the wafer W can be opposed to each other with a very small distance S therebetween. Accordingly, the chemical treatment can be performed on the wafer W in a state in which the opposing rod 14 is disposed closer to the upper surface of the wafer W. In this case, the liquid film of the chemical solution held on the upper surface of the wafer W is extremely thin. Thereby, the chemical solution can be spread over the entire upper surface of the wafer W without increasing the flow rate of the chemical solution supplied to the wafer W.

  Even if the wafer W is swung up and down by the rotation, the opposing bar 14 moves up and down following the wobbling. Therefore, the gap between the opposing rod 14 and the wafer W is always stable, and a stable liquid film of the chemical solution can be held in the stable gap. That is, the liquid film is not broken. For this reason, a stable thin liquid film is formed on the upper surface of the wafer W, and the wafer W can be processed with high quality by the chemical solution constituting the liquid film.

FIG. 10 is a schematic cross-sectional view showing the configuration of a substrate processing apparatus 100 according to another embodiment (second embodiment) of the present invention. In FIG. 10, parts corresponding to those shown in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 to 9, and description thereof is omitted.
The embodiment of FIG. 10 differs from the first embodiment in that a plurality of coil springs (tensile coil springs) 101 are used instead of the bellows 45 as an elastic body.

  The coil springs 101 are arranged at equal intervals on the circumference around the guide 35. Each coil spring 101 has one end (upper end) 102 fixed to the support bracket 20 and the other end (lower end) 103 fixed to the counter bar 14. Each coil spring 101 is in an extended state extended by gravity acting on the opposing rod 14. When the opposing bar 14 is raised relative to the support bracket 20, the coil spring 101 is compressed from the extended state. Along with this, the spring force acting on the opposing rod 14 is reduced. As a result, a part of the drag force against the gravity acting on the counter bar 14 is given by the spring force of the coil spring 101.

While the two embodiments of the present invention have been described above, the present invention can also be implemented in other forms.
For example, the nozzle 3 for supplying the processing liquid to the upper surface of the wafer W does not need to be supported by the arm 15 that supports the counter bar 14. Therefore, it may be supported by another arm different from the arm 15. Further, the nozzle 3 does not need to be in the form of a so-called scan nozzle, and may be configured to be fixedly arranged with respect to the spin chuck 2.

In the first embodiment described above, the resin bellows 45 is described as an example of the elastic body. However, the processing liquid supplied to the wafer W is a liquid that is not corrosive to metal (pure water, ionic water, In the case of functional water such as hydrogen water and magnetic water, so-called metal bellows formed using a metal material can be used instead.
Furthermore, it can also be set as the structure using plate materials, such as a leaf | plate spring and a disk spring, as an elastic body. In this case, instead of the coil spring 101 of the second embodiment, these leaf springs and disc springs are interposed. When the opposing bar 14 is light, it can also be set as the structure which does not use an elastic body.

  In each of the above-described embodiments, the upper end portion of the guide 35 is fixed to the support bracket 20, and the lower end portion of the guide 35 is inserted into the opposing rod 14 in a state in which the displacement in the vertical direction is allowed as an example. As described above, the lower end portion of the guide 35 may be fixed to the counter rod 14, that is, the upper end portion of the guide 35 may be inserted into the insertion groove (or insertion hole) of the support bracket 20.

  Further, the shape of the opposing bar 14 is not limited to the above-described configuration. For example, the head portion 33 may be configured to be provided at one end portion in the longitudinal direction instead of the central portion in the longitudinal direction. Further, although the example has been described in which the facing surface (lower surface) 43 of the liquid contact member 31 is tapered, the lower surface of the liquid contact member 31 may be a convex curved surface such as a cylindrical surface or an elliptical cylindrical surface. it can. Even in such a case, the opposing rod 14 can receive the lift from the liquid film of the processing liquid satisfactorily.

Furthermore, the cross-sectional shape of the liquid contact member 31 may be formed in a downwardly convex tip shape. That is, the facing surface 43 of the liquid contact member 31 is continuous with the first inclined surface approaching the upper surface of the wafer W as it goes upstream in the rotation direction of the wafer W, and the rotation direction of the wafer W And a second inclined surface that is separated from the upper surface of the wafer W toward the upstream side.
Further, the opposing surface 43 (lower surface) of the liquid contact member 31 can be a horizontal surface, but in this case, the opposing surface 43 is slit in the opposing surface 43 so as to receive lift from the liquid film of the chemical solution. It is desirable that recesses such as grooves, holes and the like are formed.

Further, although the opposing bar 14 is supported by the arm body 70 via the support bracket 20, the opposing bar 14 may be directly supported by the arm body 70.
In addition, the nozzle 3 for supplying the processing liquid onto the wafer W is provided separately from the counter bar 14. However, the nozzle is inserted into the counter bar 14 and the processing liquid is discharged from the counter surface 43 of the counter bar 14. It may be configured.

Further, although the rod-like counter rod 14 has been described as an example of the counter member, it may be a disc, semicircular or rectangular shape other than the rod shape.
In the above-described two embodiments, the substrate processing apparatuses 1 and 101 that sequentially supply the chemical solution and pure water to the wafer W and perform the cleaning process on the wafer W have been described as an example. It can also be applied to a substrate processing apparatus that supplies a cleaning process to the wafer W.

  In addition, various design changes can be made within the scope of matters described in the claims.

1. Substrate processing apparatus 2. Spin chuck (substrate holding means)
3 Nozzle 4 Motor (Rotating means)
14 Opposing member 20 Support bracket (supporting member)
43 Opposite surface (substrate facing area)
44 Opposing rod holding mechanism (opposing member holding mechanism)
45 Bellows 100 Substrate Processing Device 101 Coil Spring S Interval W Wafer (Substrate)

Claims (7)

A substrate holding means for holding the substrate in a horizontal position;
Rotating means for rotating the substrate held by the substrate holding means around a vertical axis;
Treatment liquid supply means for supplying a treatment liquid to the upper surface of the substrate held by the substrate holding means;
A facing member disposed opposite to the upper surface so as to be in contact with the liquid film of the processing liquid formed on the upper surface of the substrate held by the substrate holding means and receive lift from the liquid film;
A support member for supporting the opposing member;
A substrate processing apparatus, comprising: a counter member holding mechanism that holds the counter member on the support member in a state in which the counter member can be relatively displaced along a vertical direction.   The substrate processing apparatus according to claim 1, wherein the counter member holding mechanism includes an elastic body interposed between the support member and the counter member.   3. The substrate processing apparatus according to claim 1, wherein the facing member has a rod-like substrate facing region extending along a rotational radius direction of the substrate held by the substrate holding means.   The substrate processing apparatus according to claim 1, wherein the facing member has a substrate facing area extending from a rotation center of the substrate held by the substrate holding means to a peripheral edge portion of the substrate. .   The said board | substrate opposing area | region has an inclined surface which opposes the upper surface of the board | substrate hold | maintained at the said board | substrate holding means, and leaves | separates from the upper surface of the said board | substrate as it goes to the upstream of the rotation direction of the said board | substrate. Substrate processing equipment.   The said process liquid supply means includes the nozzle which discharges a process liquid toward the upstream of the area | region where the said opposing member opposes on the upper surface of the board | substrate hold | maintained at the said board | substrate holding means. The substrate processing apparatus according to item. A substrate holding and rotating step for rotating the substrate while holding it in a horizontal position;
A treatment liquid supply step for supplying a treatment liquid to the upper surface of the substrate;
The opposing member held by the support member in a state capable of relative displacement along the vertical direction is brought into contact with the liquid film of the processing liquid formed on the upper surface of the substrate so as to receive lift from the liquid film. A substrate processing method including an opposing member arranging step of opposingly arranging with an interval.

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