TW201813726A - Substrate processing apparatus - Google Patents

Abstract

The purpose of the present invention is to provide technology for suppressing the soiling of substrates. A substrate processing device comprises a substrate holding unit for holding a substrate horizontally, a processing liquid supply unit for supplying processing liquid toward the substrate held by the substrate holding unit, and a liquid receiving unit that surrounds the substrate holding unit and receives processing liquid which has splashed off of the substrate. The inner peripheral surface of the liquid receiving unit has a plurality of grooves exposed toward the substrate held by the substrate holding unit, and the direction of extension of the plurality of grooves includes vertical-direction components. As a result, droplets of processing liquid readily collect in the grooves and fall due to the weight of the droplets.

Description

   Substrate processing device   

The present invention relates to a technique for processing a substrate by supplying a processing liquid to the substrate.

Conventionally, a technique of supplying a processing liquid to a substrate while rotating the substrate is known. In such a device, the processing liquid supplied to the substrate is scattered toward the surroundings by the rotation of the substrate, thereby hitting the inner peripheral surface of the liquid receiving portion surrounding the substrate. Although most of the impacted processing liquid falls along the inner peripheral surface, a part of the impacted processing liquid may adhere to the inner peripheral surface.

If the treatment liquid attached to the inner peripheral surface of the liquid receiving portion is left out, there is a possibility that the treatment liquid solidifies and becomes particles. In addition, if the processing liquid attached to the inner peripheral surface of the liquid receiving portion is ignored, the new processing liquid scattered from the substrate toward the liquid receiving portion will hit the inner peripheral surface of the liquid receiving portion during the subsequent liquid processing. The old processing liquid may cause a phenomenon that the processing liquid bounces back toward the substrate (also referred to as a splash back phenomenon).

The generation of particles or back splashing is the cause of contaminating the substrate. Therefore, in order to suppress such contamination, Patent Document 1 discloses a technique in which a mesh member is provided on the inner side than the inner peripheral surface of the liquid receiving portion. Further, Patent Document 2 discloses a technique in which a hydrophilic member such as a PVA (polyvinyl alcohol) sponge is provided on the inner side than the inner peripheral surface of the liquid receiving portion.

    [Prior technical literature]         [Patent Literature]    

[Patent Document 1] Japanese Patent Laid-Open No. 2014-207320

[Patent Document 2] Japanese Patent Laid-Open No. 2010-149003

However, there is still room for improvement in the technology for suppressing the contamination of the substrate caused by the processing liquid attached to the inner peripheral surface of the liquid receiving portion.

The present invention has been made in view of the foregoing problems, and an object thereof is to provide a technique capable of suppressing contamination of a substrate.

In order to solve the aforementioned problems, the substrate processing apparatus of the first aspect includes a substrate holding unit that horizontally holds the substrate, and a processing liquid supply unit that supplies the processing liquid toward the substrate held by the substrate holding unit; A receiving portion surrounds the periphery of the substrate holding portion and receives the processing liquid scattered from the substrate; and a substrate rotating portion causes the substrate to lead toward the lead through the center of the substrate held by the substrate holding portion. A rotation axis extending in the vertical direction is rotated as a center; the inner peripheral surface of the liquid receiving portion has a plurality of grooves exposed toward the substrate side held by the substrate holding portion, and each of the plurality of grooves includes a vertical direction The components of direction.

The substrate processing apparatus of the second aspect is the substrate processing apparatus of the first aspect, wherein the extending direction is a direction in which a component in a rotation direction of the substrate and a component in a vertical direction are combined.

The substrate processing apparatus of the third aspect is the substrate processing apparatus of the first or second aspect, wherein the plurality of grooves include a groove deeper in the downstream portion of the substrate rotation direction than the upstream portion.

The substrate processing apparatus of the fourth aspect is the substrate processing apparatus of the first aspect, wherein the inner peripheral surface includes the plurality of grooves at least in a position perpendicular to the substrate held by the substrate holding portion.

The substrate processing apparatus of the fifth aspect is the substrate processing apparatus of the first aspect, wherein, in the circumferential direction, the inner peripheral surface alternately has the plurality of grooves which are more depressed than the reference surface; and located between adjacent grooves. And the first length of the plurality of bank portions along the reference plane, and the first length of each groove along the reference plane is longer than the second length of each bank portion along the reference plane.

The substrate processing apparatus according to the sixth aspect is the substrate processing apparatus according to any one of the first to fifth aspects, wherein the liquid receiving portion has a diameter that is relatively small and surrounds the substrate at a position closer to the substrate. A plurality of cup portions having a relatively large diameter and a cup portion on the inner side surrounding the substrate holding portion and surrounding the cup portion on the outer side of the substrate holding portion at a distance from the substrate, and at least the inner cup portion The inner bread contains the plurality of grooves.

In the substrate processing apparatuses of the first to sixth aspects, it is possible to prevent the substrate from being contaminated by the processing liquid adhered to the inner peripheral surface of the liquid receiving portion.

1. 1A‧‧‧ substrate processing equipment

9‧‧‧ Control Department

10‧‧‧ chamber

11‧‧‧ sidewall

12‧‧‧ top wall

13‧‧‧ bottom wall

14‧‧‧fan filter unit

15‧‧‧ partition

18‧‧‧ exhaust pipe

20‧‧‧Rotary chuck

21‧‧‧Swivel base

21a‧‧‧ base surface

22‧‧‧Rotary motor

23‧‧‧shielding member

24‧‧‧Rotary shaft

25‧‧‧ 锷 -shaped member

26‧‧‧Chuck pin

28‧‧‧ lower surface treatment liquid nozzle

30‧‧‧ Upper surface treatment liquid nozzle

31‧‧‧ spit out his head

32‧‧‧ Nozzle Arm

33‧‧‧Nozzle Abutment

40, 40A, 40Y‧‧‧Liquid receiving department

41‧‧‧Recycling Department

41A, 42, 43‧‧‧ cups

43a‧‧‧ lower end

43b‧‧‧upper end

43c‧‧‧Return Department

43d‧‧‧Outer upper surface

44‧‧‧ bottom

45‧‧‧Inner wall

46‧‧‧outer wall

47‧‧‧Guide

47b‧‧‧upper end

48‧‧‧ middle wall

49‧‧‧ Abandoned Ditch

50‧‧‧ inside recovery groove

51‧‧‧ Outer recovery trench

52‧‧‧Guide

52a‧‧‧ lower end

52b‧‧‧upper

52c‧‧‧Return Department

53‧‧‧ treatment liquid separation wall

60‧‧‧Two-fluid nozzle

62‧‧‧Nozzle arm

63‧‧‧Nozzle Abutment

64‧‧‧Gas head

70, 70A ~ 70C‧‧‧collection department

71, 71B, 71C‧‧‧ trench

72, 72B, 72C‧‧‧ Embankment

75, 75A, 75C‧‧‧Inner peripheral surface

76‧‧‧ datum

101, 102, 103‧‧‧ droplets

CX‧‧‧rotation axis

d1‧‧‧first length

d2‧‧‧2nd length

W‧‧‧ substrate

FIG. 1 is a plan view of the substrate processing apparatus 1.

FIG. 2 is a longitudinal sectional view of the substrate processing apparatus 1.

FIG. 3 is a cross-sectional view showing a horizontal section of the liquid collecting portion 70.

FIG. 4 is a side view of the liquid collecting portion 70 as viewed from the inside (the rotation axis CX side).

FIG. 5 is a partial enlarged view of the substrate processing apparatus 1 showing the conditions of the chemical liquid processing and the pure water rinsing processing.

FIG. 6 is a partial enlarged view of the substrate processing apparatus 1 showing the state of the IPA processing.

Fig. 7 is a diagram showing the treatment of a chemical solution in a comparative example.

FIG. 8 is a cross-sectional view schematically showing a state in which droplets 101 and 102 of a treatment liquid move in a comparative example.

FIG. 9 is a cross-sectional view schematically showing a state in which droplets 101 to 103 of the processing liquid are moved.

FIG. 10 is a result of inspection of a backlash phenomenon of a comparative example.

FIG. 11 is an inspection result of the splash back phenomenon in this embodiment.

Fig. 12 is a sectional view showing a substrate processing apparatus 1A according to a second embodiment.

Fig. 13 is a result of inspection of a splash-back phenomenon in the second embodiment.

FIG. 14 is a cross-sectional view schematically showing a state in which droplets 101 to 103 of a processing liquid are moved in a modification.

FIG. 15 is a side view of the liquid collecting portion 70C viewed from the inside (the axis of rotation CX) in the modification.

FIG. 16 is an inspection result of the splash back phenomenon in the case where the first length of each groove 71C is 8 mm and the second length of each bank portion 72C is 1 mm.

FIG. 17 is an inspection result of the splash back phenomenon in the case where the first length of each groove 71C is 4 mm and the second length of each bank portion 72C is 1 mm.

FIG. 18 is an inspection result of the splash back phenomenon in the case where the first length of each groove 71C is 2 mm and the second length of each bank portion 72C is 1 mm.

FIG. 19 is a table summarizing a plurality of inspection results of the splash back phenomenon.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Furthermore, in the drawings of FIG. 1 and the subsequent figures, for easy understanding, the size and number of each part are exaggerated or simplified as needed.

    <1 First Embodiment>         <1.1 Configuration of Substrate Processing Device 1>    

Fig. 1 is a plan view of a substrate processing apparatus 1 according to a first embodiment. FIG. 2 is a longitudinal sectional view of the substrate processing apparatus 1. This substrate processing apparatus 1 is a single-chip processing apparatus that processes substrates W for semiconductor use one sheet at a time, and performs a chemical treatment on a circular silicon substrate W and a rinse treatment using a rinse solution such as pure water, followed by drying treatment. More specifically, it is used to supply a chemical liquid such as SC1 liquid (aqueous hydrogen peroxide water mixed liquid), DHF liquid (diluted hydrofluoric acid), SC2 liquid (hydrogen hydrogen peroxide water mixed liquid) and the like to the substrate W. After the substrate W is subjected to a cleaning process (chemical solution treatment), the substrate W is rinsed using a rinse solution to remove the chemical solution from the substrate W, and the substrate W is finally subjected to a drying process of the substrate W. Further, FIG. 1 shows a state where the substrate W is held on the spin chuck 20, and FIG. 2 shows a state where the substrate W is held on the spin chuck 20.

The substrate processing apparatus 1 is provided in the chamber 10 and includes, as main components, a rotary chuck 20 that holds the substrate W in a horizontal posture (a posture in which a normal line is in a vertical direction), and an upper surface treatment liquid nozzle 30, It is used to supply a processing liquid to the upper surface of the substrate W held on the spin chuck 20; and a liquid receiving portion 40 that surrounds the periphery of the spin chuck 20 and receives the processing liquid scattered from the substrate W. Further, around the liquid receiving portion 40 in the chamber 10, a partition plate 15 for partitioning the inner space of the chamber 10 into upper and lower portions is provided. In addition, in this specification, a processing liquid is a general term which includes all the chemical liquid, a washing liquid, and a washing liquid.

The chamber 10 includes a side wall 11 along the vertical direction, a top wall 12 that closes the upper side of the space surrounded by the side wall 11, and a bottom wall 13 that closes the lower side. The space surrounded by the side wall 11, the top wall 12, and the bottom wall 13 becomes a processing space for the substrate W. Further, a part of the side wall 11 of the chamber 10 is provided with a door (both not shown) for carrying in and out of the substrate 10 and carrying the substrate W in and out of the chamber 10.

A fan filter unit (FFU) 14 is installed on the top wall 12 of the chamber 10. The fan filter unit 14 is used to further clean and supply the air in the clean room provided with the substrate processing apparatus 1 to the chamber 10. Within the processing space. The fan filter unit 14 includes a fan and a filter (for example, a HEPA filter (High-Efficiency Particulate Air Filter)) for introducing and sending air from the clean room into the chamber 10, and A downward flow of clean air is formed in the processing space in the chamber 10. In order to uniformly disperse the clean air supplied from the fan filter unit 14, a punching plate penetrating with a plurality of blow holes can also be disposed directly below the top wall 12.

The rotary chuck 20 includes a rotary base 21 having a circular plate shape fixed at an upper end of a rotary shaft 24 extending in a vertical direction in a horizontal posture. A rotary motor 22 is provided below the rotary base 21 to rotate the rotary shaft 24. The rotation motor 22 rotates the rotation base 21 in a horizontal plane via a rotation shaft 24. A cylindrical shielding member 23 is provided so as to surround the periphery of the rotation motor 22 and the rotation shaft 24.

The outer diameter of the circular plate-shaped rotary base 21 is slightly larger than the diameter of the circular substrate W held on the rotary chuck 20. Therefore, the rotary base 21 has a flat base surface 21a that is flat and faces the entire lower surface of the substrate W to be held.

A plurality of (four in this embodiment) chuck pins 26 are erected on the peripheral edge portion of the base surface 21a of the rotation base 21. The plurality of chuck pins 26 are arranged along the circumference corresponding to the outer periphery of the circular substrate W at equal intervals (as in the present embodiment, four chuck pins 26 are spaced at 90 °). The plurality of chuck pins 26 are driven in conjunction with a link mechanism (not shown) housed in the rotation base 21. The rotary chuck 20 holds the substrate W by abutting a plurality of chuck pins 26 on the outer peripheral ends of the substrate W, thereby allowing the rotary chuck 20 to be positioned horizontally above the rotary base 21 at a predetermined interval from the base surface 21a. While holding the substrate W (see FIG. 2), the plurality of chuck pins 26 can be separated from the outer peripheral end of the substrate W to release the grip.

The lower end of the shielding member 23 covering the rotary motor 22 is fixed to the bottom wall 13 of the chamber 10, and the upper end reaches directly below the rotary base 21. On the upper end portion of the shielding member 23, a cymbal member 25 is provided which protrudes substantially horizontally from the shielding member 23 to the outside and further bends and extends downward. In a state where the rotary chuck 20 is held by a plurality of chuck pins 26 to hold the substrate W, the rotary shaft 24 is rotated by the rotary motor 22, so that the substrate W can pass through the center of the substrate W and along the vertical direction. The direction of rotation axis CX rotates. The driving system of the rotary motor 22 is controlled by the control unit 9. As described above, the spin chuck 20 functions as a substrate holding means that holds the substrate W horizontally. The rotation motor 22 functions as a substrate rotation unit that rotates the substrate W held on the spin chuck 20 around the rotation axis CX.

The upper surface treatment liquid nozzle 30 is configured by attaching the discharge head 31 to the front end of the nozzle arm 32. The base end side of the nozzle arm 32 is fixed and connected to the nozzle base 33. The nozzle base 33 is configured to be rotatable around an axis in the vertical direction by a motor (not shown). By the rotation of the nozzle base 33, the processing position of the ejection head 31 of the upper surface treatment liquid nozzle 30 above the rotary chuck 20 and the standby position further outside than the liquid receiving part 40 are in an arc in the horizontal direction. To move like this. A plurality of types of processing liquid (including at least pure water) are supplied to the upper surface processing liquid nozzle 30. At the processing position, the processing liquid discharged from the discharge head 31 of the upper surface processing liquid nozzle 30 is deposited on the upper surface of the substrate W held on the spin chuck 20. In addition, by the rotation of the nozzle base 33, the upper surface treatment liquid nozzle 30 is configured to be swingable above the base surface 21a of the rotary base 21.

On the other hand, a lower surface treatment liquid nozzle 28 is provided in the vertical direction so as to pass through the inside of the rotation shaft 24. The upper end opening of the lower surface treatment liquid nozzle 28 is formed at a position facing the center of the lower surface of the substrate W held on the spin chuck 20. A plurality of types of processing liquid are also configured to be supplied to the lower surface processing liquid nozzle 28. The processing liquid discharged from the lower surface processing liquid nozzle 28 is deposited on the lower surface of the substrate W held on the spin chuck 20.

The substrate processing apparatus 1 is provided with a two-fluid nozzle 60 different from the upper surface treatment liquid nozzle 30. The two-fluid nozzle 60 is a nozzle that mixes a processing liquid such as pure water with a pressurized gas to generate a liquid droplet, and sprays a mixed fluid (two-fluid) of the liquid droplet and the gas onto the substrate W. The two-fluid nozzle 60 is configured by attaching a liquid head (not shown) to the front end of the nozzle arm 62 and attaching the gas head 64 to a support member provided so as to diverge from the nozzle arm 62. The proximal end side of the nozzle arm 62 is fixed and connected to the nozzle base 63. The nozzle base 63 is configured to be rotatable around an axis in the vertical direction by a motor (not shown). When the nozzle base 63 rotates, the two-fluid nozzle 60 moves in a circular arc shape in a horizontal direction between a processing position above the rotary chuck 20 and a standby position further outside than the liquid receiving portion 40. A processing liquid such as pure water is supplied to the liquid head, and a pressurized inert gas (nitrogen (N2) in the present embodiment) is supplied to the gas head 64. At the processing position, the mixed fluid of the processing liquid sprayed from the two-fluid nozzle 60 is blown against the upper surface of the substrate W held on the spin chuck 20. In this way, the lower surface processing liquid nozzle 28, the upper surface processing liquid nozzle 30, and the two-fluid nozzle 60 function as processing liquid supply sections that supply processing liquid toward the substrate W held on the spin chuck 20, respectively.

The liquid receiving section 40 includes a recovery section 41 and cups 42 and 43 that can be raised and lowered independently of each other. The recovery portion 41 surrounds the periphery of the spin chuck 20 and has a shape that is substantially rotationally symmetric with respect to a rotation axis CX passing through the center of the substrate W held by the spin chuck 20. The recovery portion 41 is integrally provided with a bottom portion 44 which is annular in a plan view, a cylindrical inner wall portion 45 rising upward from an inner peripheral edge of the bottom portion 44 and a circle rising upward from an outer peripheral edge of the bottom portion 44. A cylindrical outer wall portion 46 and a cylindrical middle wall portion 48 standing upward from between the inner wall portion 45 and the outer wall portion 46.

The inner wall portion 45 is formed in such a length as to be accommodated in a state where the recovery portion 41 is raised to the highest level with a proper gap between the shielding member 23 and the cymbal member 25. The middle wall portion 48 is formed in a length that is accommodated in a state where the recovery portion 41 and the cup 42 are closest to each other, and maintains an appropriate gap between the guide portion 52 and the processing liquid separation wall 53 described later in the cup 42.

Between the inner wall portion 45 and the middle wall portion 48, a waste channel 49 is provided for collecting and discarding the used processing liquid. In addition, between the middle wall portion 48 and the outer wall portion 46, a ring-shaped outer side recovery groove 51 for collecting and recovering the used processing liquid is provided.

A waste liquid mechanism (not shown) is connected to the waste ditch 49 for discharging the liquid collected in the waste ditch 49 and forcibly exhausting the waste ditch 49. There are four exhaust liquid mechanisms provided at regular intervals along the circumferential direction of the waste trench 49, for example. A recovery mechanism (not shown) is connected to the outer recovery trench 51 for recovering the processing liquid collected in the outer recovery trench 51 to a recovery tank provided outside the substrate processing apparatus 1. Furthermore, the bottom of the outer recovery groove 51 is inclined at a slight angle with respect to the horizontal direction, and a recovery mechanism is connected to its lowest position. Thereby, the processing liquid flowing into the outer recovery groove 51 can be smoothly recovered.

The cup 42 surrounds the circumference of the spin chuck 20 and has a shape that is substantially rotationally symmetric with respect to a rotation axis CX passing through the center of the substrate W held by the spin chuck 20. The cup 42 is integrally provided with a guide portion 52 and a cylindrical treatment liquid separation wall 53 connected to the guide portion 52.

The guide portion 52 has a lower end portion 52a coaxial with the lower end portion of the middle wall portion 48 inside the middle wall portion 48 of the recovery portion 41, and draws a smooth arc from the upper end of the lower end portion 52a toward the center side. (In the direction close to the rotation axis CX of the substrate W) The upper end portion 52b extends obliquely upward, and the folded-back portion 52c formed by folding the front end portion of the upper end portion 52b downward. The lower end portion 52 a is accommodated in the waste trench 49 while maintaining a proper gap between the recovery portion 41 and the cup 42, and the inner wall portion 45 and the middle wall portion 48.

The upper end portion 52b of the guide portion 52 is formed to be thicker as it goes downward, and the treatment liquid separation wall 53 has a cylindrical shape provided to extend downward from the outer peripheral edge portion of the lower end of the upper end portion 52b. The treatment liquid separation wall 53 is accommodated in the outer recovery groove 51 while maintaining an appropriate gap between the recovery portion 41 and the cup 42 in a state where the recovery portion 41 is closest to the cup 42.

The cup 43 surrounds the rotation chuck 20 on the outer side of the guide portion 52 of the cup 42 and has a substantially rotationally symmetrical shape with respect to a rotation axis CX passing through the center of the substrate W of the rotation chuck 20. The cup 43 has a function as a guide. The cup 43 has a lower cylindrical end portion 43a coaxial with the lower end portion 52a of the guide portion 52, and is slanted toward the center side (close to the rotation axis CX of the substrate W) while drawing a smooth arc from the upper end of the lower end portion 43a. The upper end portion 43b is extended upward, and the folded-back portion 43c is formed by folding the front end portion of the upper end portion 43b downward.

The lower end portion 43 a is accommodated in the outer recovery groove 51 with an appropriate gap between the recovery portion 41 and the cup 43 in a state closest to the treatment liquid separation wall 53 of the cup 42 and the outer wall portion 46 of the recovery portion 41. . In addition, the upper end portion 43b is provided so as to overlap the guide portion 52 of the cup 42 in the up-down direction, and is close to the upper end portion of the guide portion 52 at a very small interval in a state where the cup 42 and the cup 43 are closest to each other. 52b. In addition, the folded-back portion 43c formed by folding the front end portion of the upper end portion 43b downward is formed in a state where the cup 42 and the cup 43 are closest to each other, and the folded-back portion 43c and the folded-back portion 52c of the guide portion 52 overlap in the horizontal direction. .

The recovery unit 41 and the cups 42 and 43 are raised and lowered independently of each other. That is, each of the recovery units 41 and the cups 42 and 43 is provided with a separate lifting mechanism (not shown), so that it can be lifted individually and independently. As such a lifting mechanism, for example, various known mechanisms such as a ball screw mechanism or a cylinder can be used.

In addition, the liquid receiving portion 40 includes a cylindrical liquid collecting portion 70 attached to the inside of the lower end portion 52 a of the cup 42. FIG. 3 is a cross-sectional view showing a horizontal section of the liquid collecting portion 70. FIG. 4 is a side view of the liquid collecting portion 70 as viewed from the inside (the rotation axis CX side).

The inner peripheral surface 75 of the liquid collecting portion 70 has a plurality of grooves 71 exposed toward the substrate W side held by the spin chuck 20. The extending direction of each groove 71 is along the vertical direction. The inner peripheral surface 75 alternately has a plurality of grooves 71 which are more recessed than the reference surface 76 in the circumferential direction, and a plurality of bank portions 72 located between adjacent grooves 71 and along the reference surface 76.

Each groove 71 has the same shape and size, and each groove 71 has a semicircular depression when viewed from the top. The shape and size of each bank portion 72 are also the same. The first length d1 (for example, 8 mm) of each groove 71 along the reference plane 76 is longer than the second length d2 (for example, 1 mm) of each bank section 72 along the reference plane 76. From the standpoint of receiving the processing liquid, the liquid collecting unit 70 preferably has chemical resistance and the like, and is made of, for example, a Teflon (registered trademark) material. More specifically, the liquid collecting portion 70 is made of, for example, PTFE (polytetrafluoroethylene; polytetrafluoroethylene).

The liquid collecting part 70 merges the droplets of the processing liquid scattered from the substrate W and adheres to the inner peripheral surface 75 in the grooves 71, and makes the merged droplets along the extending direction of the grooves 71 due to their own weight. Fall down. The dropped liquid droplets are discharged from the substrate processing apparatus 1 through a waste liquid mechanism (not shown) through the waste groove 49.

The partition plate 15 is provided to partition the inner space of the chamber 10 up and down around the liquid receiving portion 40. The partition plate 15 may be a plate-like member that surrounds one piece of the liquid receiving portion 40 or may be formed by joining a plurality of plate-like members. Further, the partition plate 15 may be formed with a through hole or a notch penetrating in the thickness direction. In this embodiment, a nozzle base 33 for supporting the upper surface treatment liquid nozzle 30 and the two-fluid nozzle 60 is formed. The support shaft of 63 passes through the through hole.

The outer peripheral end of the partition plate 15 is connected to the side wall 11 of the chamber 10. In addition, the edge portion of the surrounding liquid receiving portion 40 of the partition plate 15 is formed in a circular shape having a larger diameter than the outer diameter of the cup 43. Therefore, the partition plate 15 does not become an obstacle to the raising and lowering of the cup 43.

An exhaust pipe 18 is provided in a part of the side wall 11 of the chamber 10 and near the bottom wall 13. The exhaust pipe 18 is connected to an exhaust mechanism (not shown). Of the clean air supplied from the fan filter unit 14 and flowing through the chamber 10, the air passing between the liquid receiving portion 40 and the partition plate 15 is discharged from the device through the exhaust pipe 18.

The hardware configuration of the control unit 9 provided in the substrate processing apparatus 1 is the same as that of a general computer. That is, the control unit 9 is configured to include a CPU (Central Processing Unit) that performs various arithmetic processing, and a ROM (Read Only Memory) that is a memory dedicated to reading the basic program. , RAM (Random Access Memory), which is a readable and writable memory for storing various information, and a magnetic disk in which control software and data are stored in advance. The CPU of the control unit 9 executes a predetermined processing program so that each operating mechanism of the substrate processing apparatus 1 is controlled by the control unit 9 to perform processing in the substrate processing apparatus 1.

    <1.2 example of processing>    

An example of the processing procedure of the substrate W will be briefly described. Hereinafter, the surface of the rotating substrate W is sequentially subjected to a chemical liquid treatment, a pure water rinse treatment, and an IPA (isopropyl alcohol; isopropyl alcohol) treatment, and then the substrate W is rotated at a higher speed to perform a spin-drying and drying treatment. The situation will be explained. When performing each process on the substrate W, the substrate W is held on the spin chuck 20 and the liquid receiving portion 40 is raised and lowered.

FIG. 5 is a partial enlarged view of the substrate processing apparatus 1 showing the conditions of the chemical liquid processing and the pure water rinsing processing. FIG. 6 is a partial enlarged view of the substrate processing apparatus 1 showing the state of the IPA processing. In FIGS. 5 and 6, the processing liquid flowing on the upper surface of the substrate W is indicated by solid arrows, and the processing liquid scattered from the edge of the substrate W to the side is indicated by two dotted arrows. An example of processing will be described below with reference to FIGS. 5 and 6.

When the substrate W is treated with a chemical solution, for example, the recovery unit 41 and the cups 42 and 43 are all raised so that the periphery of the substrate W held by the spin chuck 20 is surrounded by the guide portion 52 of the cup 42 (FIG. 5). In this state, the substrate W is rotated together with the spin chuck 20, and a chemical solution (for example, DHF liquid) is supplied from the ejection head 31 to the upper surface of the substrate W. The supplied chemical liquid flows along the upper surface of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and finally scatters from the edge of the substrate W toward the side. Thereby, the chemical processing of the substrate W is performed. The chemical liquid scattered from the edge of the rotating substrate W flows down the inner wall of the guided portion 52 and the inner peripheral surface 75 of the liquid collecting portion 70, and is discharged from the waste groove 49.

Next, the substrate W is subjected to a pure water rinse process. At this time, for example, all of the recovery unit 41 and the cups 42 and 43 are raised, and the state where the periphery of the substrate W held on the spin chuck 20 is surrounded by the guide portion 52 of the cup 42 is maintained (FIG. 5). In this state, the substrate W is rotated together with the spin chuck 20, and pure water is supplied from the ejection head 31 to the upper surface of the substrate W. The supplied pure water flows along the upper surface of the substrate W by the centrifugal force generated by the rotation of the substrate W, and finally scatters from the edge of the substrate W toward the side. Thereby, the substrate W is rinsed with pure water. The pure water scattered from the edge of the rotating substrate W flows down the inner wall of the guide portion 52 and the inner peripheral surface 75 of the liquid collecting portion 70, and is discharged from the waste trench 49.

Next, the substrate W is subjected to IPA processing. At this time, for example, the recovery unit 41 and the cup 42 are lowered, and only the cup 43 is raised. As a result, an opening is formed between the upper end portion 43b of the cup 43 and the upper end portion 52b of the guide portion 52 of the cup 42 to surround the substrate W held by the spin chuck 20 (FIG. 6). In this state, the substrate W is rotated together with the spin chuck 20, and the IPA self-ejecting head 31 is supplied to the upper surface of the substrate W. The supplied IPA flows along the upper surface of the substrate W due to the centrifugal force generated by the rotation of the substrate W, and finally scatters from the edge of the substrate W toward the side. Thereby, the IPA processing of the substrate W is performed. The IPA scattered from the edge of the rotating substrate W is received by the upper end portion 52b of the cup 42 and the upper end portion 43b of the cup 43, and flows down along the outer surface of the cup 42 and the inner surface of the cup 43 and is recovered to Outside recovery groove 51.

When the spin-drying and drying process is performed, the recovery portion 41 and the cups 42 and 43 are all lowered so that the upper surface 43d on the outer side of the upper end portion 43b of the cup 43 is positioned lower than the substrate W held by the spin chuck 20 (Fig. 2). In this state, the substrate W is rotated at high speed together with the spin chuck 20, and the water droplets attached to the substrate W are spin-dried by centrifugal force and dried.

    <1.3 effects>    

Fig. 7 is a diagram showing the treatment of a chemical solution of a comparative example. In FIG. 7, the processing liquid flowing on the upper surface of the substrate W is indicated by a solid line arrow, and the processing liquid scattered from the end edge portion of the substrate W to the side is indicated by two dotted arrows. FIG. 8 is a cross-sectional view schematically showing how the droplets 101 and 102 of the treatment liquid move in the comparative example. FIG. 9 is a cross-sectional view schematically showing a state in which droplets 101 to 103 of the processing liquid are moved in this embodiment. In FIGS. 8 and 9, the moving direction of each droplet is indicated by a solid line arrow.

If the treatment liquid attached to the inner peripheral surface of the liquid receiving portion 40 is left untreated, there is a possibility that the treatment liquid is solidified and becomes particles, or a splash-back phenomenon may occur. Since the generation of particles and the phenomenon of back splashing can cause the substrate to be contaminated, it is desirable to suppress such contamination.

The liquid receiving portion 40Y of the comparative example is different from the liquid receiving portion 40 of the present embodiment in that the liquid receiving portion 70 is not provided inside the guide portion 52. Therefore, in the comparative example, if the substrate W is subjected to the liquid treatment, the droplets 101 of the lysate from the place where the end edge of the rotating substrate W is scattered will first adhere to the inner wall of the guide portion 52. A part of the adhered droplet 102 remains attached to the inner wall of the guide portion 52, and the remaining droplet 102 flows down the inner wall of the guide portion 52 and is discharged from the waste groove 49.

In contrast, the liquid receiving portion 40 of this embodiment has a liquid collecting portion 70 on the inner side of the guide portion 52, and thereby a plurality of grooves 71 are formed on the inner peripheral surface of the liquid receiving portion 40. Therefore, in this embodiment, if the substrate W is subjected to liquid treatment, the droplets 101 of the processing liquid scattered from the edge of the rotating substrate W will first adhere to the inner peripheral surface 75 of the liquid collecting portion 70. Most of the attached droplets 102 flow along a semicircular curved surface of each groove 71 and merge with other attached droplets 102. As a result, the combined droplets 103 fall downward along the extending direction of the groove 71 (vertical direction in this embodiment) due to the relatively larger weight of the droplets 103 compared to the droplets 102.

As described above, in this embodiment, by advancing the confluence of the droplets 102 adhering to the inner peripheral surface of the liquid receiving portion 40, it is possible to suppress the state of the droplets 102 adhering to the inner peripheral surface of the liquid receiving portion 40. As a result, it is possible to reduce the risk of contamination caused by ignoring the state in which the droplet 102 is attached to the inner peripheral surface (or even causing the generation of particles or splashing back).

In particular, the aspect of the present embodiment in which droplets adhered to the inner peripheral surface of the liquid receiving portion 40 are dropped quickly is maintained in comparison with Patent Document 1 and Patent, which are supplemented by droplets on the inner peripheral surface of the liquid receiving portion. The appearance of reference 2 can more effectively reduce the risk of pollution.

FIG. 10 is a result of inspection of a backlash phenomenon of a comparative example. FIG. 11 is an inspection result of the splash back phenomenon in this embodiment. In this inspection, a PH (acid-base) test paper is affixed to the upper side of the upper end portion 43b of the cup 43, and the substrate W is subjected to liquid treatment in the raised and lowered states of the liquid receiving portions 40Y and 40 shown in Figs. 7 and 5. Specifically, the liquid processing is a liquid processing in which the DHF is supplied from the ejection head 31 on the rotation axis CX at a flow rate of 500 ml per minute to the upper surface of the substrate W which is rotated at a rotation speed of 800 rpm. This liquid treatment was performed 5 times in total, and the PH test paper was replaced with a new one each time. The “Number of discolored parts” column in FIG. 10 and FIG. 11 indicates the number of parts where the droplets of the treatment liquid adhere to the PH test paper and the pH test paper changes color.

As shown in FIGS. 10 and 11, if the five inspections are averaged, about 51 color-changing sites are generated in the PH test paper compared to the comparative example. In this embodiment, only 0.6 color-changing sites are generated in the PH test paper. In general, since the liquid droplets scattered from the substrate W move from the substrate W to a substantially horizontal direction, it is difficult to directly drop the liquid droplets in the ascending and descending states of the liquid receiving portions 40Y and 40 shown in FIGS. 7 and 5. It is attached to the upper side of the upper end portion 43b of the cup 43. In this way, the droplets attached to the upper side of the upper end portion 43b of the cup 43 are droplets generated by the collision of the processing liquid scattered from the substrate toward the liquid receiving portions 40Y and 40 and the processing liquid splashed back from the liquid receiving portions 40Y and 40. The probability is high. From this point of view, if the inspection results of the view 10 and FIG. 11 are re-examined, it can be known that, compared with the comparative example, this embodiment mode can reduce the back splash phenomenon by about 90%. This case can be considered as the effect of this embodiment which suppresses the state where the droplet 102 is attached to the inner peripheral surface of the liquid receiving portion 40.

In particular, in the present embodiment, when the liquid receiving portion 70 is used for receiving liquid (in the case shown in FIG. 5), the inner peripheral surface 75 of the liquid collecting portion 70 is at least held by the rotating chuck 20. The substrate W includes a plurality of grooves 71 at the same position in the vertical direction. Generally, the liquid droplets scattered from the substrate W move from the substrate W in a substantially horizontal direction. Therefore, by providing a plurality of grooves 71 in the same vertical direction as the substrate W, adhesion to the liquid receiver can be more effectively promoted. Convergence of the droplets 102 on the inner peripheral surface of the portion 40.

In this embodiment, each groove 71 and each bank portion 72 are alternately arranged along the circumferential direction, and the first length d1 (for example, 8 mm) of each groove 71 along the reference surface 76 is longer along The second length d2 (for example, 1 mm) of each bank portion 72 of the reference surface 76 is long. Therefore, the inner peripheral surface is formed by a groove 71 that makes the plurality of droplets merge relatively stronger along a semicircular curved surface than the bank portion 72 where the effect of the plurality of liquid droplets merge is relatively weak. Most of 75 can promote the convergence of the droplets 102 attached to the inner peripheral surface of the liquid receiving portion 40 more effectively.

In this embodiment, the liquid receiving portion 40 includes an inner cup 42 having a relatively small diameter and surrounding the rotation chuck 20 at a position closer to the substrate W, and an outer cup 43 having a relatively opposite diameter. It is large and surrounds the periphery of the chuck 20 at a position far from the substrate W. Further, by providing the liquid collecting portion 70 on the inner side of the inner cup 42, the inner peripheral surface of the cup 42 includes a plurality of grooves 71. Generally, when the processing liquid is adhered to the inner peripheral surface closer to the substrate W, compared with the case where the processing liquid is adhered to the inner peripheral surface of the cup farther from the substrate W, the particles are generated or splashed back due to the phenomenon. The risk of substrate contamination is increased. In this embodiment, by providing the liquid collection part 70 inside the cup 42 which has a high risk of substrate contamination, this risk can be reduced more effectively.

    <2Second Embodiment>    

Fig. 12 is a sectional view showing a substrate processing apparatus 1A according to a second embodiment. The overall configuration and processing operation of the substrate processing apparatus 1A of the second embodiment are substantially the same as those of the first embodiment. The difference between the second embodiment and the first embodiment lies mainly in the configuration of the liquid receiving portion 40A and the liquid collecting portion 70A.

The liquid receiving portion 40A of the second embodiment includes a cup 41A instead of the collecting portion 41 of the first embodiment. The cup 41A has, in addition to each configuration of the recovery portion 41, a guide portion 47 which stands between the inner wall portion 45 and the middle wall portion 48, and the upper end portion faces a center side while drawing a smooth arc. (In the direction close to the rotation axis CX of the substrate W held on the spin chuck 20) extends obliquely upward.

The guide portion 47 has an upper end portion 47 b extending obliquely upward toward the center side (in the direction close to the rotation axis CX of the substrate W) while drawing a smooth arc.

Further, a circular inner recovery groove 50 is provided between the guide portion 47 and the middle wall portion 48 to collect and recover the used processing liquid. The configuration of the inner recovery groove 50 is the same as the configuration of the outer recovery groove 51 described above. Specifically, a recovery mechanism (not shown) is connected to the inner recovery groove 50 for recovering the processing liquid collected in the inner recovery groove 50 to a recovery tank provided outside the substrate processing apparatus 1. In addition, the bottom of the inner recovery groove 50 is inclined at a slight angle with respect to the horizontal direction, and a recovery mechanism is connected to its lowest position. Thereby, the processing liquid flowing into the inner recovery groove 50 can be smoothly recovered.

The upper end portion 52 b of the guide portion 52 of the cup 42 is provided so as to overlap the upper end portion 47 b of the guide portion 47 of the cup 41 in the vertical direction. Therefore, when the cup 41 and the cup 42 are closest to each other, the upper end portion 52 b of the guide portion 52 is kept close to the upper end portion 47 b of the guide portion 47 at a very small interval. In addition, the folded-back portion 52c formed by folding the front end of the upper end portion 52b downward is configured to overlap the front end of the upper end portion 47b of the guide portion 47 in a horizontal direction in a state where the cup 41 and cup 42 are closest to each other. length.

In addition, the liquid receiving portion 40A includes a cylindrical liquid collecting portion 70A that is mounted inside the guide portion 47 of the cup 41A. The inner peripheral surface 75A of the liquid collecting portion 70A has a plurality of grooves and a plurality of banks exposed alternately in the circumferential direction in the same circumferential direction as the inner peripheral surface 75 of the aforementioned embodiment and exposed on the substrate W side of the rotary chuck 20. Crotch (both are not shown). Also, as in the first embodiment, the first length (for example, 8 mm) of each groove along the reference plane is longer than the second length (for example, 1 mm) of each bank section along the reference plane. The liquid collecting part 70A merges the droplets of the processing liquid scattered from the substrate W and adhered to the inner peripheral surface 75 in the respective grooves, and causes the combined droplets to drop downward along the extending direction of the grooves due to their own weight. . The dropped liquid droplets are discharged from the substrate processing apparatus 1A through the waste groove 49 and the exhaust liquid mechanism (not shown).

Fig. 13 is a result of inspection of a splash-back phenomenon in the second embodiment. In this inspection, the pH test paper is attached to the upper side of the upper end portion 43 b of the cup 43, and the substrate W is subjected to liquid treatment while the cups 41A, 42, and 43 are raised. Specifically, the liquid treatment is a liquid treatment in which DHF is supplied from the ejection head 31 located on the rotation axis CX at a flow rate of 500 ml per minute to the upper surface of the substrate W that is rotated at a rotation speed of 800 rpm. This liquid treatment was performed 5 times in total, and the PH test paper was replaced with a new one each time. Moreover, the "number of discolored parts" column in FIG. 13 shows the number of parts where the droplets of the treatment liquid adhered to the pH test paper and the pH test paper changed color.

As shown in FIG. 13, if the five inspections are averaged, the second embodiment generates about 164 discolored sites on the PH test paper. Comparing the inspection results of the second embodiment (FIG. 13) with the inspection results of the first embodiment (FIG. 11), the pH test paper of the second embodiment has many discolored parts. The reason may be due to the liquid receiving position (the guide portion 47 and the liquid collecting portion 70A of the cup 41A) in the second embodiment compared to the liquid receiving position (the guiding portion 52 and the liquid collecting portion 70 of the cup 42) in the first embodiment. It is closer to the substrate W, so that the processing liquid scattered from the substrate W toward the liquid receiving portion 40A easily collides with the processing liquid splashed back from the liquid receiving portion 40A.

In the second embodiment, as in the first embodiment, by providing the liquid collecting portion 70A, the risk of contamination of the substrate can be reduced compared to the case where the liquid collecting portion 70A is not provided.

Also, in the second embodiment, similarly to the first embodiment, since a plurality of grooves are provided at positions in the same vertical direction as the substrate W, adhesion to the inner peripheral surface of the liquid receiving portion 40A can be more effectively promoted. Confluence of droplets.

In addition, in the second embodiment, as in the first embodiment, the effect of converging a plurality of liquid droplets is relatively stronger than that of a bank where the effect of converging a plurality of liquid droplets is relatively weak. The grooves form most of the inner peripheral surface 75A, and can more effectively promote the confluence of the droplets attached to the inner peripheral surface of the liquid receiving portion 40A.

In the second embodiment, as in the first embodiment, the risk can be reduced more effectively by providing the liquid collecting portion 70A inside the cup 41 which is close to the substrate W and has a high risk of substrate contamination.

    <3 modifications>    

Although the embodiment of the present invention has been described above, the present invention can be modified in various ways other than those described above without departing from the gist thereof.

In the foregoing embodiment, the description has been given of the state in which the liquid collecting portions 70 and 70A formed with the grooves and the bank portions are installed inside the guide portions 52 and 47 of the cups 42 and 41A, but it is not limited. herein. For example, by cutting the inside of the guide portions 52 and 47 of the cups 42 and 41A, a groove and a bank (ie, a liquid collecting portion) can be formed inside the guide portions 52 and 47.

Moreover, in the said 1st Embodiment, although the aspect which provided the liquid collecting part 70 in the one part inside the lower part 52a of the guide part 52 was demonstrated, it is not limited to this. For example, the liquid collecting portion 70 may be provided on the inside of the lower end portion 52a of the guide portion 52, or the liquid collecting portion may be provided on the inside of the lower end portion 52a and the upper end portion 52b of the guide portion 52. The appearance of the Department 70.

In each of the foregoing embodiments, a description has been given of a case where the liquid collecting portions 70 and 70A are provided on the inner peripheral surface of the innermost cup of the plurality of cups included in the liquid receiving portion 40 and 40A. Not limited to this. If a liquid collection part can be provided in the plurality of cups at least on the inner peripheral surface of the innermost cup, the risk of substrate contamination can be reduced more effectively. Moreover, a liquid collection part may be provided in the plurality of cups only on the inner peripheral surface of the cups other than the innermost cup.

Furthermore, in the first embodiment described above, the description has been given of the case where the liquid collecting portion 70 is made of PTFE, but the liquid collecting portion 70 may be made of other materials (for example, PFA (Polyfluoroalkoxy; Fluoroalkoxy vinyl ether copolymer)).

FIG. 14 is a cross-sectional view schematically showing a case where the droplets 101 to 103 of the processing liquid are moved in the modification. FIG. 14 illustrates two grooves 71B of the plurality of grooves of the liquid collecting portion 70B according to the modification. In FIG. 14, the rotation direction of the substrate W (not shown) is the counterclockwise direction of the paper surface, and the droplets 101 scattered from the substrate W are moved along the trajectory of a solid arrow.

The plurality of grooves of the liquid collecting portion 70B include grooves 71B in which the portion on the downstream side is deeper than the portion on the upstream side in the rotation direction of the substrate W. In other words, the plurality of grooves of the liquid collecting portion 70B include grooves 71B which are recessed in a direction inclined with respect to the radial direction of the substrate W toward the rotation direction of the substrate W. As a result, the droplets 102 scattered from the substrate W and dripping into the groove 71B will easily flow in the groove 71B along the scattering potential, and thus easily merge with other droplets 102. In this way, by deforming the recessed shape of the groove 71B, the liquid droplets can be merged with each other, and the state where the liquid droplets 102 adhere to the inner peripheral surface of the liquid receiving portion can be suppressed.

FIG. 15 is a side view of the liquid collecting portion 70C viewed from the inside (the rotation axis CX side) in the modification. FIG. 16 is an inspection result of the splash back phenomenon when the first length of each groove 71C is 8 mm and the second length of each bank portion 72C is 1 mm. FIG. 17 is an inspection result of the splash back phenomenon when the first length of each groove 71C is 4 mm and the second length of each bank portion 72C is 1 mm. FIG. 18 is an inspection result of the splash back phenomenon when the first length of each groove 71C is 2 mm and the second length of each bank portion 72C is 1 mm.

As shown in FIG. 15, the inner peripheral surface 75C of the liquid collecting portion 70C alternately has a plurality of grooves 71C which are more concave than the reference surface in the circumferential direction, and a plurality of banks located between the adjacent grooves 71C and along the reference surface.埂 部 72C. The extending direction of each groove 71C is a direction (more specifically, a direction inclined by 45 degrees) composed of the components in the rotation direction of the substrate W (the direction from right to left in FIG. 15) and the components in the vertical direction.

Therefore, in this modification, the droplets of the processing liquid scattered by the rotating substrate W are received by the inner peripheral surface 75C of the liquid collecting portion 70C, and then are scattered downward along the plurality of grooves 71C along the scattering tendency. flow. In addition, by rotating the substrate W with the rotation motor 22, an air flow is generated in the inner peripheral surface 75C of the liquid collecting portion 70C along the extending direction of each groove 71C, and the droplets adhering to the inner peripheral surface 75C can be dropped.

Furthermore, it can be seen from FIG. 19 that the inspection results of FIG. 16 to FIG. 18 are aggregated. By setting the first length to be short, the possibility of causing a splash-back phenomenon can be reduced. This case is presumably due to the narrowing of the width of the groove 71C, which makes it easier for a plurality of droplets to converge in the groove 71C. However, from the viewpoint of combining a plurality of droplets in the groove 71C, it is preferable to set the first length to be wider than the diameter (for example, 1 to 2 mm) of the droplets scattered from the substrate W.

In addition, as shown in FIG. 19 where the inspection results of FIG. 16 to FIG. 18 are summarized, if the second length is short, the possibility of causing a splash-back phenomenon can be reduced. This is presumably due to the narrowing of the width of the embankment portion 72C, which makes it difficult for droplets to adhere to the embankment portion 72C (to make it easier for the droplets to move adjacent to the embankment portion 72C). 71C on both sides of the groove).

In addition, in each of the above-mentioned embodiments, although a plurality of cups capable of lifting and lowering the liquid receiving portion independently are provided, the plurality of cups may be raised and lowered by being integrally formed. In addition, the liquid receiving portion 40 may be provided with only one cup surrounding the rotary base 21.

The substrate to be processed by the substrate cleaning device 1 is not limited to a substrate for semiconductor applications, and may be a substrate for solar cells or a glass substrate for a flat panel display such as a liquid crystal display device.

In addition, the substrate processing apparatus 1 may be a device that supplies a processing liquid to its surface while rotating a substrate held on a spin chuck, and receives a processing liquid scattered from the substrate through a cup, except for a single piece. In addition to the cleaning processing device or etching processing device of the above-mentioned type, for example, a spin coating device (spin coater) or a spin developing device (spin developer) that applies a photoresist may be used. .

Although the substrate processing apparatus of the embodiment and its modification has been described above, these are examples of the preferred embodiment of the present invention and do not limit the scope of implementation of the present invention. The present invention can freely combine the various embodiments within the scope of the invention, or can deform any constituent element of each embodiment, or omit any constituent element in each embodiment.

Claims (6)

    A substrate processing apparatus includes: a substrate holding section that holds a substrate horizontally; a processing liquid supply section that supplies a processing liquid toward the substrate held by the substrate holding section; and a liquid receiving section that surrounds the substrate holding Around the part, the processing liquid scattered from the substrate is received; and the substrate rotating part makes the substrate center on a rotation axis extending in the vertical direction through the center of the substrate held by the substrate holding part. Rotating; the inner peripheral surface of the liquid receiving portion has a plurality of grooves exposed toward the substrate side held by the substrate holding portion, and the extending direction of each of the plurality of grooves includes a component in a vertical direction.         The substrate processing apparatus according to claim 1, wherein the extending direction is a direction in which a component in a rotation direction of the substrate and a component in a vertical direction are combined.         According to the substrate processing apparatus of claim 1, wherein the plurality of grooves include a groove deeper in the downstream portion of the substrate rotation direction than the upstream portion.         The substrate processing apparatus according to claim 1, wherein the inner peripheral surface includes the plurality of grooves at least in the same vertical direction as the substrate held by the substrate holding portion.         The substrate processing apparatus according to claim 1, wherein in the circumferential direction, the inner peripheral surface alternately has the plurality of grooves which are more recessed than the reference surface, and the plurality of grooves located between adjacent grooves and along the reference surface. The first length of each bank along the reference plane is longer than the second length of each bank along the reference plane.         The substrate processing apparatus according to any one of claims 1 to 5, wherein the liquid receiving portion has a cup portion covering an inner side that surrounds the periphery of the substrate holding portion from a relatively small diameter and a position closer to the substrate, The plurality of cup portions are relatively large in diameter and surround the cup portion on the outer side of the substrate holding portion at a position farther from the substrate, and at least the inner bread of the inner cup portion contains the plurality of grooves.