Substrate processing apparatus
Patent Information
- Application Number
- JP2022123167
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-08-02
- Publication Date
- 2025-08-01
- Estimated Expiration
- 2042-08-02
AI Technical Summary
Existing substrate processing equipment faces issues with processing liquid splashing or rebounding on the substrate surface, leading to product defects such as water marks, despite the use of fan filter units (FFUs) to suppress splashing, as increasing FFU airflow risks mist leakage.
A substrate processing apparatus with a rotary table, liquid receiving section, and airflow forming mechanism that concentrates downward airflow within a processing chamber, enhancing airflow without increasing FFU output, using a cylindrical airflow forming mechanism to amplify airflow through the Coanda effect.
The apparatus effectively suppresses processing liquid re-adhesion to the substrate surface, improving product quality by increasing airflow without FFU output increase, reducing energy consumption, and efficiently discharging mist, while maintaining chamber cleanliness.
Smart Images
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Abstract
Description
[Technical field]
[0001] An embodiment of the present invention relates to a substrate processing apparatus. [Background technology]
[0002] Substrate processing apparatuses that perform chemical processing or cleaning processing on substrates such as semiconductor wafers widely use a single-wafer processing method in which substrates are processed one by one from the viewpoint of uniformity and reproducibility of processing. Substrate processing apparatuses using the single-wafer processing method fix the substrate to a rotating table, rotate the substrate about an axis perpendicular to the center of the substrate, and supply a processing liquid (e.g., chemical liquid or pure water) to the center of the substrate to process the substrate surface. The processing liquid supplied to the substrate surface spreads toward the edge of the substrate due to centrifugal force, peels off from the edge of the substrate, and is received by the inner surface of a cup that covers the periphery of the rotating table.
[0003] In addition, the substrate processing apparatus is provided with a fan filter unit (FFU) installed on the ceiling side of the processing chamber. The FFU generates a downflow by blowing clean air downward from the ceiling side, and keeps the processing chamber at a high level of cleanliness. For example, the FFU supplies the downflow of clean air generated by the FFU to the substrate surface, thereby suppressing splashing and bouncing of the processing liquid supplied to the substrate surface and preventing it from scattering from the substrate surface to the outside of the cup. In addition, the downflow exhausts air from the lower side of the processing chamber, and discharges the processing liquid peeled off from the edge of the substrate and dust floating in the processing chamber together with the air from the processing chamber. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2014-27201 A Summary of the Invention [Problem to be solved by the invention]
[0005] In the above-mentioned substrate processing apparatus, even when the above-mentioned FFU is used, when the processing liquid is supplied to the surface of the substrate to process the substrate surface, the processing liquid may splash or bounce on the surface of the substrate or around the substrate. Such splash or bounce of the processing liquid may cause redeposition of the processing liquid on the substrate surface, which may cause product defects. For example, in a drying process for drying the surface of the substrate, if the processing liquid that has been blown up by splash or bounce adheres to the substrate surface after the drying process has been completed, water marks (water stains) will appear on the substrate surface, which will reduce the quality of the product. Therefore, it is important to suppress the splash or bounce of the processing liquid in order to suppress redeposition of the processing liquid on the substrate surface and improve the quality of the product.
[0006] As a measure to suppress the splashing and bouncing of the processing liquid, it is conceivable to increase the amount of air sent out from the FFU to generate a stronger downflow, thereby further suppressing the splashing and bouncing of the processing liquid on the surface of the substrate. However, if the amount of air sent out from the FFU is increased, the pressure inside the processing chamber increases, and there is a risk that mist of the processing liquid in the processing chamber will flow out of the processing chamber. Therefore, it is not possible to increase the amount of air sent out from the FFU, and it is difficult to further suppress the splashing and bouncing of the processing liquid.
[0007] The present invention has been made to solve the above-mentioned problems, and its object is to provide a substrate processing apparatus that can increase the amount of downflow air toward the surface of the substrate without increasing the amount of air sent out from the FFU, thereby preventing re-adhesion of processing liquid onto the substrate surface. [Means for solving the problem]
[0008] In order to solve the above-mentioned problems and achieve the object, a substrate processing apparatus according to one aspect of the present invention includes a processing chamber, a turntable, a supply unit, a liquid receiving unit, a blower unit, and an airflow generating unit. The processing chamber is formed of a ceiling and a base that are opposed to each other in the vertical direction. The turntable is provided on the base side of the processing chamber and rotates a substrate. The supply unit supplies a processing liquid to the substrate held on the turntable. The liquid receiving unit is provided to surround the turntable, has a circular opening at the upper end, and receives processing liquid scattered from the substrate that rotates due to the rotation of the turntable. The blower unit is provided on the ceiling side of the processing chamber and generates a downward airflow within the processing chamber. The airflow generating unit is provided between the liquid receiving unit and the blower unit and concentrates the downward airflow generated by the blower unit inside the opening in the liquid receiving unit. Effect of the Invention
[0009] According to one aspect of the present invention, it is possible to increase the amount of downflow air toward the surface of the substrate without increasing the amount of air sent out from the FFU, thereby preventing re-adhesion of the processing liquid onto the substrate surface. [Brief description of the drawings]
[0010] [Figure 1A] FIG. 1A is a diagram showing a schematic configuration of a substrate processing apparatus according to a first embodiment. [Figure 1B] FIG. 1B is a schematic diagram for explaining an overview of the air flow creation mechanism according to the first embodiment. [Figure 2A] FIG. 2A is a side view of the air flow creation mechanism according to the first embodiment. [Figure 2B] FIG. 2B is a top view of the air flow creation mechanism according to the first embodiment. [Diagram 3] FIG. 3 is a diagram illustrating an example of the configuration of the air flow creation mechanism according to the first embodiment. [Figure 4A] FIG. 4A is a cross-sectional view showing a schematic configuration of the air flow creation mechanism according to the first embodiment. [Figure 4B] FIG. 4B is a cross-sectional view showing a schematic configuration of the air flow creation mechanism according to the first embodiment. [Diagram 5] FIG. 5 is a diagram for explaining the size and installation position of the air flow creation mechanism according to the first embodiment. [Figure 6] FIG. 6 is a diagram for explaining an air flow formed by the air flow creation mechanism according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the substrate processing apparatus disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the substrate processing apparatus disclosed in the present application is not limited to the following embodiment.
[0012] (First embodiment) FIG. 1A is a diagram showing a schematic configuration of a substrate processing apparatus 1 according to a first embodiment. As shown in FIG. 1A, the substrate processing apparatus 1 has an inner chamber 11. The inner chamber 11 is partitioned into two spaces, upper and lower, by a partition wall 11a, and the lower space is formed as a processing chamber 11b. That is, the processing chamber 11b is formed by the partition wall 11a (ceiling) and base body 21 (base) facing each other in the vertical direction, and the side wall of the inner chamber 11. Note that the above-mentioned upper and lower refer to the upper and lower sides in the substrate processing apparatus 1 (that is, the upper and lower sides in FIG. 1A). Here, in this embodiment, the upper and lower sides may be described as the upper and lower sides, respectively.
[0013] The inner chamber 11 is provided with a loading / unloading port (not shown) at a position corresponding to one of the processing chambers 11b in the side wall. The loading / unloading port is an entrance for loading and unloading the substrate W into and from the processing chamber 11b, and is formed by an openable / closable shutter or the like. The substrate processing apparatus 1 opens the shutter when loading the substrate W into the processing chamber 11b and when unloading the processed substrate W from the processing chamber 11b, allowing a transport arm transporting the substrate W to be inserted into the processing chamber 11b. The shutter is kept closed while the substrate W is being processed.
[0014] As shown in FIG. 1A, the substrate processing apparatus 1 includes a base body 21 having a through hole in the center, a turntable 22 rotatably disposed above the base body 21, a motor 23 serving as a drive source for the turntable 22, a ring-shaped liquid receiving section 24 (cup) surrounding the turntable 22, a nozzle 25 (supply section) for supplying processing liquid to the substrate W, a fan filter unit (FFU) 26 (blower section), an ionizer 27 (static electricity removal section), an airflow forming mechanism 30 (airflow forming section), a control device 40 (control section), and a gas supply source 50 (gas supply section).
[0015] The turntable 22 is disposed on the upper surface side of the base body 21, and is fixed to the upper end of the rotor 23b of the motor 23 so that the central axis coincides with the rotation axis of the motor 23. In addition, the turntable 22 has a plurality of (e.g., six) chuck pins 22a arranged at predetermined intervals on the surface on which the substrate W is placed. The plurality of chuck pins 22a fix the substrate W to the turntable 22 by gripping the outer peripheral surface of the substrate W to be processed.
[0016] The motor 23 is composed of a cylindrical stator 23a and a cylindrical rotor 23b rotatably inserted into the stator 23a. The stator 23a is attached to the lower surface side of the base body 21, and the upper end side of the rotor 23b is connected to the turntable 22 on the upper surface side of the base body 21. The motor 23 is an example of a drive source for rotating the turntable 22. The motor 23 is electrically connected to the control device 40 and is driven according to the control of the control device 40. As a result, the turntable 22 is rotated by the drive of the motor 23. The central rotation axis of the turntable 22 and the motor 23 becomes the substrate rotation axis A1.
[0017] The liquid receiving section 24 is composed of an annular movable liquid receiving section 24a and an annular fixed liquid receiving section 24b that receive the processing liquid scattered or flowing down from the substrate W. The liquid receiving section 24 is formed so as to surround the turntable 22. That is, the liquid receiving section 24 is opened so that the surface of the substrate W held on the turntable 22 is exposed. The movable liquid receiving section 24a is configured to be movable in the vertical direction by a lifting mechanism (not shown) such as a cylinder. The upper part of the movable liquid receiving section 24a is inclined toward the inside in the radial direction. The fixed liquid receiving section 24b is fixed to the upper surface of the base body 21, and the bottom surface of the fixed liquid receiving section 24b is connected to a pipe 12 for discharging the gas in the processing chamber 11b and the processing liquid (e.g., chemical liquid, pure water, etc.) discharged from the substrate W.
[0018] The piping 12 is connected to an exhaust pipe 14 leading to an exhaust pump (not shown) that discharges the gas inside the processing chamber 11b to the outside, and to a waste liquid pipe 13 for discharging the processing liquid that is received by the liquid receiving portion 24 and drips to the outside.
[0019] The nozzle 25 supplies the processing liquid to the substrate W held on the turntable 22. Specifically, the nozzle 25 is held by a nozzle moving mechanism provided at a predetermined position on the base body 21, and sprays the processing liquid downward during processing of the substrate W. The nozzle moving mechanism has a movable arm and an arm swinging mechanism, and reciprocates the nozzle 25 between the center of the substrate W and the periphery of the substrate W when processing the substrate W. Specifically, the nozzle 25 is provided at one end of the movable arm, and the other end is supported by the arm swinging mechanism. The arm swinging mechanism swings the movable arm with the other end of the movable arm as a fulcrum. When processing of the substrate W is completed, the arm swinging mechanism swings the movable arm so as to retreat the nozzle 25 to a standby position away from the substrate W.
[0020] The FFU 26 is provided on the partition wall 11a of the inner chamber 11. The FFU 26 has a built-in fan and a filter (e.g., an Ultra Low Penetration Air Filter (ULPA) filter) installed below the fan, and sends clean gas that has passed through the filter into the processing chamber 11b through the partition wall 11a. In the processing chamber 11b, a downward air current toward the base body 21 side is generated by the gas sent out by the FFU 26.
[0021] The ionizer 27 is a long, thin rod-shaped (bar-type) static eliminator that is provided below the FFU 26 and removes static electricity. Specifically, the ionizer 27 is configured to selectively emit either positive or negative ions, and imparts ions to the gas sent out from the FFU 26. As a result, the gas to which the ions have been imparted is supplied to the substrate W, and the charge on the substrate W is neutralized.
[0022] The airflow forming mechanism 30 is provided between the liquid receiving unit 24 and the FFU 26 and above the nozzle 25 (in other words, the movable arm) arranged above the substrate W, and concentrates the downward airflow generated by the FFU 26 inside the opening in the liquid receiving unit 24. FIG. 1B is a schematic diagram for explaining an overview of the airflow forming mechanism 30 according to the first embodiment. As shown in FIG. 1B, the airflow forming mechanism 30 is formed in a cylindrical (ring-like) shape having circular openings (upper opening 30a and lower opening 30b) at the upper and lower ends, respectively, and is installed below the ionizer 27 so that the central axis of the turntable 22 coincides with the center of the opening 30a and the opening 30b. The airflow forming mechanism 30 takes in the downward airflow generated by the FFU 26 provided on the ceiling side of the processing chamber 11b and to which ions are added by the ionizer 27 from the upper opening 30a, and sends it from the lower opening 30b to the inside of the upper opening 24c of the liquid receiving part 24. Here, the airflow forming mechanism 30 is formed so as to increase the downward airflow (downflow) sent to the inside of the upper opening 24c of the liquid receiving part 24 by the attraction phenomenon and Coanda effect caused by discharging the gas supplied by the gas supply source 50. The airflow forming mechanism 30 will be described in detail later.
[0023] The control device 40 controls each component including the motor 23 and the gas supply source 50. For example, the control device 40 controls the gas supply source 50 to control the supply of gas to the air flow creation mechanism 30.
[0024] The gas supply source 50 is connected to the airflow formation mechanism 30 via piping. The gas supply source 50 is also electrically connected to the control device 40, and supplies gas (e.g., nitrogen gas or air) to the airflow formation mechanism 30 according to the control by the control device 40. Here, a filter (e.g., a ULPA filter, etc.) similar to that of the FFU 26 is installed in the piping connecting the gas supply source 50 and the airflow formation mechanism 30. That is, the airflow formation mechanism 30 is supplied with clean gas that has passed through the filter, and discharges the supplied clean gas.
[0025] The airflow formation mechanism 30 according to this embodiment will be described in detail below. FIG. 2A is a side view of the airflow formation mechanism 30 according to the first embodiment. FIG. 2B is a top view of the airflow formation mechanism 30 according to the first embodiment. For example, as shown in FIG. 2A and FIG. 2B, the airflow formation mechanism 30 has four gas inlets 31a formed at equal intervals on its side. The gas inlets 31a communicate a chamber (space) formed inside the airflow formation mechanism 30 with the outside of the airflow formation mechanism 30. The gas inlets 31a have an opening on the outside side connected to a pipe connected to the gas supply source 50. That is, the gas inlets 31a are inlets that introduce the gas supplied from the gas supply source 50 into the chamber formed inside the airflow formation mechanism 30. For example, the airflow formation mechanism 30 is held at a position below the ionizer 27 by supporting the outer circumferential surfaces of the four gas inlets 31a with a support member (not shown).
[0026] 3 is a diagram showing an example of the configuration of the airflow creation mechanism 30 according to the first embodiment. As shown in FIG. 3, the airflow creation mechanism 30 is formed of a first annular member 31 and a second annular member 32. Specifically, the airflow creation mechanism 30 is formed by overlapping the inner wall surface of the first annular member 31, in which the gas inlet 31a is formed, with the second annular member 32 so as to cover a part of the outer wall surface of the first annular member 31. That is, the outer diameter of the upper end of the second annular member 32 is formed smaller than the inner diameter of the lower end of the first annular member 31, and the first annular member 31 is overlapped with the second annular member 32, thereby forming the airflow creation mechanism 30.
[0027] Here, the airflow forming mechanism 30 has a chamber for storing and compressing gas therein formed by stacking a first annular member 31 on a second annular member 32. Fig. 4A is a cross-sectional view showing a schematic configuration of the airflow forming mechanism 30 according to the first embodiment. Fig. 4A shows a cross-sectional view of the AA cross section in Fig. 3. That is, Fig. 4A is a cross-sectional view of a cross section in the vertical direction of the substrate processing apparatus 1.
[0028] 4A, in the air flow creation mechanism 30, a chamber 33 is formed by overlapping a first annular member 31 on a second annular member 32. Specifically, in the air flow creation mechanism 30, a chamber 33 is formed that is surrounded by the inner wall surface of the first annular member 31 and a part of the outer wall surface of the second annular member 32. Here, in the air flow creation mechanism 30, the chamber 33 is formed around the entire inner circumference thereof.
[0029] The chamber 33 is connected to four gas inlets 31a (not shown) and to a slit 34 (gas discharge section) formed around the entire inner circumference of the airflow generating mechanism 30. Gas is supplied to the chamber 33 from the gas supply source 50 through the four gas inlets 31a. The gas supplied from the gas supply source 50 spreads inside the chamber 33 and is discharged from the slit 34. Here, the chamber 33 has a buffer function for enabling the gas supplied from the gas supply source 50 to be stably discharged from the entire circumference of the slit 34. Specifically, when gas is supplied from the gas supply source 50, the chamber 33 becomes filled with gas throughout, and the gas is continuously supplied, and the gas is discharged from the slit 34 while maintaining the filled state.
[0030] In order to realize such a buffer function, the chamber 33 is connected to the gas inlet 31a and the slit 34 at positions offset in the vertical direction. FIG. 4B is a cross-sectional view showing a schematic configuration of the airflow forming mechanism according to the first embodiment. FIG. 4B is a cross-sectional view of a cross section including the gas inlet 31a in the vertical direction of the substrate processing apparatus 1. As shown in FIG. 4B, the gas inlet 31a is provided in an outer wall 37 on the lower end side of the chamber 33, and introduces gas supplied from the gas supply source 50 into the chamber 33. Also, as shown in FIG. 4B, the slit 34 is provided in an inner wall 36 on the upper end side of the chamber 33.
[0031] 4B, the gas introduced into the chamber 33 from the four gas inlets 31a is retained in the chamber 33 without being immediately discharged from the slits 34. As a result, the chamber 33 is filled with gas, and the gas supplied from the gas supply source 50 is discharged stably from the entire circumference of the slits 34.
[0032] 4A, the airflow generating mechanism 30 is formed by fitting the first annular member 31 above the second annular member 32 and joining the second annular member 32 and the first annular member 31 together. Here, a joining portion 39 between the second annular member 32 and the first annular member 31 is formed with a structure having high airtightness so that the gas supplied to the chamber 33 does not leak. For example, as shown in FIG. 4A, the joining portion 39 is formed by forming a notch on the lower end of the inner wall of the first annular member 31, and forming a notch on the outer wall of the second annular member 32 that engages with the notch. Note that a seal member may be used for the joining portion 39 to maintain higher airtightness.
[0033] As shown in FIG. 4, the airflow creating mechanism 30 has, in a vertical cross section, an inner wall 36 whose central portion in the vertical direction curves toward the outer wall 37, a slit 34 provided in the inner wall 36 for discharging gas that flows toward the opening 30b at the lower end, and a curved surface 35 whose outer shape bulges upward in a vertical cross section, extends upward from the upper end of the outer wall 37, and then extends downward to the position of the slit 34.
[0034] The outer wall 37 is the outer wall surface of the airflow creation mechanism 30 in a state in which the first annular member 31 is overlapped with the second annular member 32, and is constituted by the outer wall surface of the first annular member 31 and a part of the outer wall surface of the second annular member 32 (the outer wall surface that does not form the chamber 33). The inner wall 36 corresponds to the inner wall surface of the second annular member 32, and is formed so as to be inclined inward toward the upper end side in a cross section in the vertical direction. In other words, the second annular member 32 is formed so that the inner diameter gradually becomes smaller toward the upper end side.
[0035] The curved surface 35 is formed on the upper end side of the first annular member 31, and is composed of a curved surface that descends from the upper end of the first annular member 31 toward the upper end of the outer wall surface, and a curved surface that descends from the upper end of the first annular member 31 toward the inside to the slit 34. Note that, as shown in Fig. 4, the inner wall surface of the first annular member 31 has an outer shape that bulges upward in a vertical cross section, and is formed so that the end of the inner wall surface is connected to the end of the curved surface 35 on the slit 34 side.
[0036] The slit 34 is a space formed by the wall surface near the position where the inner wall surface of the first annular member 31 is connected to the curved surface 35 and the end surface on the upper end side of the second annular member 32 (a plane connecting the outer wall surface and the inner wall surface of the second annular member 32), and communicates the chamber 33 with the outside (the inside of the airflow formation mechanism 30). The slit 34 discharges the gas supplied to the chamber 33 so that it flows toward the opening 30b at the lower end. In addition, a part of the discharged gas flows toward the opening 30b at the lower end along the inner wall 36. That is, the slit 34 diffuses and discharges the gas accumulated and compressed in the chamber 33 toward the opening 30b at the lower end of the airflow formation mechanism 30, and a part of the diffused gas flows toward the opening 30b at the lower end along the inner wall 36. As described above, the slits 34 are formed in the inner wall 36 around the entire circumference of the air flow creation mechanism 30, and stably discharge the gas from the entire circumference. Therefore, the slits 34 diffuse and discharge the gas from the entire circumference of the air flow creation mechanism 30 toward the opening 30b at the lower end, and a part of the discharged gas flows along the inner wall 36 around the entire circumference of the inner wall 36 of the air flow creation mechanism 30.
[0037] Next, the size and installation position of the air flow creation mechanism 30 will be described. Fig. 5 is a diagram for explaining the size and installation position of the air flow creation mechanism 30 according to the first embodiment. Note that Fig. 5 shows a cross-sectional view of a cross section in the up-down direction, similar to Fig. 4.
[0038] The width "a" of the slit 34 shown in FIG. 5 (the distance between the inner wall surface of the first annular member 31 forming the slit 34 and the end surface on the upper end side of the second annular member 32) is formed to a size that allows the wind speed of the gas discharged from the slit 34 to be a desired wind speed. Specifically, the slit 34 is formed to a width "a" that realizes a downward airflow with a wind speed that can entrain the surrounding gas near the opening 30a at the upper end of the airflow generating mechanism 30. That is, the slit 34 is formed to a width "a" (for example, about 0.1 mm to 1.5 mm) that discharges the gas at a wind speed that can cause the attraction phenomenon and the Coanda effect. Here, in order to discharge the gas discharged from the slit 34 while accelerating it at the slit 34 so as to have the above-mentioned wind speed, the pressure of the gas supplied to the chamber 33 is adjusted so that the pressure in the chamber 33 becomes a predetermined pressure. For example, a gas of 0.3 Mpa to 0.5 Mpa is supplied to the chamber 33 and compressed to the above-mentioned predetermined pressure in the chamber 33. In this way, by forming the slit 34 with a predetermined width and adjusting the pressure inside the chamber 33 to a predetermined pressure, the slit 34 can eject gas at a wind speed capable of causing the attraction phenomenon and the Coanda effect.
[0039] As described above, the slits 34 discharge gas at a wind speed that allows the induction phenomenon and the Coanda effect to occur, so that the volume of gas sent out from the airflow creation mechanism 30 (i.e., the volume of gas sent out from the lower opening 30b) becomes greater than the volume of air from the FFU 26. That is, the volume of gas sent out from the lower opening 30b becomes greater than the volume of air from the FFU 26 due to the airflow discharged from the slits 34 and the airflow generated by the induction phenomenon and the Coanda effect. For example, the volume of gas sent out from the lower opening 30b becomes more than twice the volume of air from the FFU 26.
[0040] The shape of the wall of the slit 34 is set so that the gas discharge angle "θ" at the slit 34 is a desired angle. That is, the shape of the wall of the slit 34 is set so that the gas discharged from the slit 34 spreads in the vertical direction in a desired manner. For example, the shape of the wall of the slit 34 is set so that the gas discharged from the slit 34 flows toward the opening 30b at the lower end of the airflow creation mechanism 30, and is discharged at an angle "θ" such that a part of the gas flows along the inner wall 36. The width "a" of the slit 34 and the gas discharge angle "θ" are optimally determined from experiments, simulations, and the like.
[0041] 5, the airflow creating mechanism 30 is formed so that the inner diameter "b" of the opening 30b at the lower end is smaller than the inner diameter "c" of the opening 24c at the upper end of the liquid receiving portion 24. That is, since the airflow sent out from the lower end of the airflow creating mechanism 30 diffuses in the radial direction of the airflow creating mechanism 30, in order to concentrate the airflow sent out from the lower end of the airflow creating mechanism 30 inside the opening 24c at the upper end of the liquid receiving portion 24, the inner diameter "b" of the opening 30b at the lower end is formed so as to be smaller than the inner diameter "c" of the opening 24c at the upper end of the liquid receiving portion 24.
[0042] Further, the distance "d" between the upper opening 24c of the liquid receiving portion 24 and the lower opening 30b of the airflow generating mechanism 30 is determined based on the inner diameter "b" of the lower opening 30b, the inner diameter "c" of the upper opening 24c of the liquid receiving portion 24, and the diffusion angle "φ" of the airflow at the lower opening 30b. That is, the distance "d" is determined so that the airflow diffused at the angle "φ" at the lower opening 30b is contained inside the inner diameter "c" of the upper opening 24c of the liquid receiving portion 24. Here, the distance "d" is determined so as to be a height that does not hinder the swinging of the movable arm by the arm swinging mechanism while satisfying the above-mentioned conditions. The inner diameter "b" of the lower opening 30b and the distance "d" are optimal values determined from experiments, simulations, etc.
[0043] By providing the above-mentioned airflow forming mechanism 30, the substrate processing apparatus 1 can increase the amount of airflow of the downflow to the surface of the substrate without increasing the amount of air sent out from the FFU 26. FIG. 6 is a diagram for explaining the airflow formed by the airflow forming mechanism 30 according to the first embodiment. As described above, the airflow forming mechanism 30 supplies gas to the chamber 33 via the gas inlet 31a and discharges the airflow from the slit 34. As a result, as shown in FIG. 6, the airflow is discharged from the slit 34 toward the opening 30b of the airflow forming mechanism 30 with force. This is because the gas compressed in the chamber 33 is discharged through the narrow opening of the slit 34. As described above, the opening diameter (width) of the slit 34 is formed to be about several millimeters (for example, 0.1 mm to 1.5 mm). That is, the gas flows from the chamber 33 toward the very narrow slit 34, so the speed of the airflow in the slit 34 becomes faster (Bernoulli's theorem). As a result, the gas discharged from the slit 34 is ejected with force. In this way, by forcibly expelling gas from slit 34, the force that draws in the surrounding gas at opening 30a at the upper end of airflow creation mechanism 30 is strengthened, and as a result, the amount of air sent out from opening 30b at the lower end of airflow creation mechanism 30 becomes several times the amount of air from FFU 26.
[0044] As described above, the airflow forming mechanism 30 takes in the downward airflow from the FFU 26 (airflow that directly enters the inside of the airflow forming mechanism 30 from the FFU 26) and entrains the gas around the airflow forming mechanism 30 (particularly, around the upper end of the airflow forming mechanism 30), thereby increasing the amount of airflow sent out from the opening 30b at the lower end of the airflow forming mechanism 30. Furthermore, the gas discharged from the slit 34 is sent out from the lower end of the airflow forming mechanism 30, entraining the gas around the lower end of the airflow forming mechanism 30 (i.e., the opening 30b) (attraction phenomenon), forming a downward airflow. Furthermore, the downward airflow sent out from the opening 30b at the lower end is supplied to the substrate W while taking in the gas around the airflow, so that the amount of airflow of the downward airflow supplied to the substrate W is further increased. That is, by using the airflow forming mechanism 30, a downward airflow larger than the amount of air sent out from the FFU 26 can be intensively sent to the substrate W. Here, in order to draw in surrounding air into the air flow creation mechanism 30, a curved surface 35 is formed at the upper end, generating the Coanda effect in which the air follows the curved surface.
[0045] In this manner, the substrate processing apparatus 1 supplies gas from the gas supply source 50 to the airflow forming mechanism 30 and expels the airflow forcefully from the slit 34, thereby forming a downflow stronger than the downflow delivered from the FFU 26 inside the opening 24c at the upper end of the liquid receiving section 24. Here, the substrate processing apparatus 1 can form a downflow concentrated inside the opening 24c at the upper end of the liquid receiving section 24 at any timing. Specifically, the substrate processing apparatus 1 forms a downflow by the airflow forming mechanism 30 while processing the substrate W is being performed, and stops formation of the downflow by the airflow forming mechanism 30 while processing the substrate W is not being performed.
[0046] An example of the timing when processing is not being performed on the substrate W is the timing when the substrate W is loaded into or unloaded from the processing chamber 11b. That is, the controller 40 controls the gas supply source 50 to stop supplying gas when the substrate W is loaded into or unloaded from the processing chamber 11b. In this case, for example, the controller 40 controls the gas supply source 50 to stop supplying gas while the shutter of the loading / unloading port for the substrate W is open.
[0047] The above example is merely an example, and the downflow may be formed by the airflow forming mechanism 30 at any other timing. For example, the control device 40 may control the airflow forming mechanism 30 to form a downflow only in the drying process of the substrate W.
[0048] As described above, according to the first embodiment, the processing chamber 11b is formed of the partition wall 11a and the base body 21 which face each other in the vertical direction. The turntable 22 is provided on the base body 21 side of the processing chamber 11b and rotates the substrate W. The nozzle 25 supplies the processing liquid to the substrate W held on the turntable 22. The liquid receiving part 24 is provided so as to surround the turntable 22, has a circular opening 24c at the upper end, and receives the processing liquid scattered from the substrate W which rotates by the rotation of the turntable 22. The FFU 26 is provided on the partition wall 11a side of the processing chamber 11b and generates a downward air current in the processing chamber 11b. The air current generating mechanism 30 is provided between the liquid receiving part 24 and the FFU 26 and concentrates the downward air current generated by the FFU 26 inside the opening 24c in the liquid receiving part 24. Therefore, the substrate processing apparatus 1 according to the first embodiment can increase the amount of downflow air toward the surface of the substrate W and suppress splashing and bouncing of the processing liquid on the surface of the substrate without increasing the amount of air sent out from the FFU 26. As a result, the substrate processing apparatus 1 can suppress redeposition of the processing liquid onto the substrate W and improve the substrate quality.
[0049] Furthermore, the substrate processing apparatus 1 can prevent the generation of turbulent air currents around the liquid receiving portion 24 by concentrating the downward air currents generated by the FFU 26 on the inside of the opening 24c in the liquid receiving portion 24. For example, when a downward air current from the FFU 26 flows around the liquid receiving portion 24 (for example, a position where the nozzle 25 is provided), the downward air current may bounce off the upper surface of the base body 21, causing a turbulent air current. When a mist of the processing liquid is generated, such a turbulent air current may cause the mist of the processing liquid to fly up in the processing chamber, causing the mist to reattach to the substrate W. The substrate processing apparatus 1 according to this embodiment can prevent the generation of such turbulent air currents by concentrating the downward air currents on the inside of the opening 24c in the liquid receiving portion 24, and can prevent the mist of the processing liquid from flying up in the processing chamber 11b even when the mist of the processing liquid is generated. As a result, the substrate processing apparatus 1 can prevent the processing liquid from reattaching to the substrate W.
[0050] According to the first embodiment, the airflow generating mechanism 30 is formed in a cylindrical shape having circular openings at the upper and lower ends, and has an inner wall 36 whose central portion in the vertical direction is curved toward the outer wall 37 in the vertical cross section, a slit 34 provided in the inner wall 36 for discharging gas flowing toward the opening 30b at the lower end, and a curved surface 35 whose outer shape is a curved surface that bulges upward in the vertical cross section, extends upward from the upper end of the outer wall 37, and then extends downward to the position of the slit 34. The airflow generating mechanism 30 takes in a downward airflow from the opening 30a at the upper end and sends out a downward airflow from the opening 30b at the lower end to the inside of the opening 24c in the liquid receiving section 24. Therefore, the substrate processing apparatus 1 according to the first embodiment can generate the induction phenomenon and the Coanda effect to amplify the downflow, and can reduce the amount of air from the FFU 26. As a result, the substrate processing apparatus 1 can reduce the energy consumption related to substrate processing.
[0051] Moreover, the substrate processing apparatus 1 can improve the efficiency of discharging the processing liquid by concentrating the downward air current inside the opening 24c in the liquid receiving section 24. As described above, the substrate processing apparatus 1 increases the amount of air flowing in the liquid receiving section 24 compared to the case where only the conventional FFU generates a downward air current. Therefore, the flow speed of the air flowing in the liquid receiving section 24 also increases, and the mist of the processing liquid scattered from the substrate W and the mist floating around the substrate W can be easily sent to the pipe 12. In this way, the substrate processing apparatus 1 can efficiently discharge the mist of the processing liquid, and as a result, the mist of the processing liquid can be suppressed from floating around the substrate W and the processing liquid can be suppressed from re-attaching to the upper surface of the substrate W.
[0052] According to the first embodiment, the inner diameter of the lower opening 30b of the airflow forming mechanism 30 is smaller than the inner diameter of the upper opening 24c of the liquid receiving portion 24. The airflow forming mechanism 30 is provided in the processing chamber 11b such that the distance between the lower opening 30b and the upper opening 24c of the liquid receiving portion 24 is based on the inner diameter of the lower opening 30b, the inner diameter of the upper opening 24c of the liquid receiving portion 24, and the diffusion angle of the airflow at the lower opening 30b. Therefore, the substrate processing apparatus 1 according to the first embodiment can take into account the diffusion of the airflow and can concentrate the downward airflow inside the opening 24c of the liquid receiving portion 24 with high accuracy.
[0053] Moreover, according to the first embodiment, the ionizer 27 is provided below the FFU 26 to remove static electricity. The airflow generating mechanism 30 is installed below the ionizer 27. Therefore, the substrate processing apparatus 1 according to the first embodiment can concentrate the downward airflow to which ions are added by the ionizer 27 on the inside of the opening 24c in the liquid receiving part 24, and can neutralize the charge on the substrate W.
[0054] Moreover, according to the first embodiment, the gas supply source 50 supplies the gas to be discharged through the slit 34. The gas flow generating mechanism 30 is formed of a first annular member 31 and a second annular member 32. The first annular member 31 and the second annular member 32 form a chamber 33 for storing and compressing the gas. The slit 34 discharges the gas supplied from the gas supply source 50 to the chamber 33. Therefore, the substrate processing apparatus 1 according to the first embodiment can stably discharge the gas from the slit 34.
[0055] Furthermore, by configuring the chamber 33 to which the gas is supplied to be formed by two members (the first annular member 31 and the second annular member 32), the airflow generating mechanism 30 can be disassembled and cleaned. Therefore, the inside of the chamber 33 can be always kept clean, and it is possible to prevent contaminated gas from being supplied to the substrate W, thereby avoiding contamination of the substrate W.
[0056] Furthermore, according to the first embodiment, gas inlet 31a for introducing gas supplied from gas supply source 50 into chamber 33 is provided in outer wall 37 on the lower end side of chamber 33, and slit 34 is provided in inner wall 36 on the upper end side of chamber 33. Therefore, the substrate processing apparatus 1 according to the first embodiment can create a state in which the entire chamber 33 is filled with gas, and can stably discharge gas from the entire circumference of slit 34.
[0057] Moreover, according to the first embodiment, the control device 40 controls the supply of gas by the gas supply source 50. The control device 40 controls the gas supply by the gas supply source 50 to stop when the substrate W is loaded or unloaded into or from the processing chamber 11b. Therefore, the substrate processing apparatus 1 according to the first embodiment can avoid applying an unnecessary strong downflow to the substrate W when the substrate W is loaded or unloaded. [Explanation of symbols]
[0058] 1. Substrate Processing Equipment 11b Processing Room 22 Rotating Table 24 Liquid receiving part 24c, 30a, 30b opening 25 Nozzles 26 FFU 27 Ionizer 30 Airflow formation mechanism 31 First annular member 31a Gas inlet 32 Second annular member 33 Chamber 34 Slit 35 Curved surface 36 Inner wall 37 Exterior Wall 40 Control device 50 Gas supply source
Claims
1. A processing chamber for processing a substrate, a rotating table provided in the processing chamber for holding and rotating the substrate, a supply unit for supplying a processing liquid to the substrate held on the rotating table, a liquid receiving part provided so as to surround the rotating table, having a circular opening at the upper end, and receiving the processing liquid scattered from the substrate rotating due to the rotation of the rotating table, a blowing unit provided on the ceiling side of the processing chamber for generating a downward airflow in the processing chamber, an airflow forming part provided between the liquid receiving part and the blowing unit, formed in a cylindrical shape having circular openings at the upper end and the lower end respectively, and concentrating the downward airflow generated by the blowing unit inside the opening at the upper end of the liquid receiving part, comprising the airflow forming part has an inner wall, an outer wall, and a curved surface, the curved surface has an outer shape that bulges upward in a vertical cross-section, and is a curved surface connecting the outer wall and the inner wall, a substrate processing apparatus.
2. The inner wall is curved in the direction of the outer wall in the vertical cross-section, the airflow forming part further has a gas discharge part provided on the inner wall for discharging the gas flowing toward the opening at the lower end, the substrate processing apparatus according to Claim 1.
3. The inner diameter of the opening at the lower end of the airflow forming part is smaller than the inner diameter of the opening at the upper end of the liquid receiving part, the substrate processing apparatus according to Claim 1 or 2.
4. The airflow forming part is provided in the processing chamber such that the distance between the opening at the lower end and the opening at the upper end of the liquid receiving part is a distance based on the inner diameter of the opening at the lower end, the inner diameter of the opening at the upper end of the liquid receiving part, and the diffusion angle of the airflow at the opening at the lower end, the substrate processing apparatus according to Claim 3.
5. provided below the blowing unit, further comprising an electrostatic removal unit for removing static electricity, the airflow forming part is installed below the electrostatic removal unit, the substrate processing apparatus according to Claim 1 or 2.
6. further comprising a gas supply unit for supplying the gas discharged by the gas discharge part, the airflow forming part is formed from a first annular member and a second annular member, the first annular member and the second annular member form a space for storing and compressing the gas, the gas discharge part discharges the gas supplied from the gas supply unit into the space, the substrate processing apparatus according to Claim 2.
7. A gas inlet for introducing the gas supplied from the gas supply unit into the space is provided on the outer wall on the lower end side of the space. The substrate processing apparatus according to claim 6, wherein the gas discharge unit is provided on the inner wall on the upper end side of the space. **Claim 8** The apparatus further includes a control unit configured to control the supply of the gas by the gas supply unit. The substrate processing apparatus according to claim 6, wherein the control unit is configured to control the gas supply unit to stop the supply of the gas when the substrate is loaded into and unloaded from the processing chamber.