Liquid Treatment Equipment

Abstract

To inhibit clogging of an exhaust path by foreign objects occurring during rotary application processing of a substrate.SOLUTION: A liquid processing apparatus that applies a coating liquid onto a substrate, includes: a substrate holder that holds and rotates the substrate; a coating liquid supplier that applies the coating liquid to the substrate held by the substrate holder; and a cup which surrounds the substrate held by the substrate holder. The cup includes: an outer cup portion arranged outside the substrate holder; an inner cup portion arranged on an inner peripheral side of the outer cup portion and below the substrate holder and having a downwardly-extending wall; an exhaust path provided between the outer cup portion and the inner cup portion; and a coating liquid collector provided with a plurality of openings through which exhaust flow passes, the coating liquid collector extending downward below the wall of the inner cup portion with a gap formed between itself and a lower end of the wall. The liquid processing apparatus includes a solvent supply part which supplies a solvent of the coating liquid to the coating liquid collector.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] TECHNICAL FIELD The present disclosure relates to liquid treatment devices. [Background technology]

[0002] Patent Document 1 discloses a liquid processing apparatus for applying a coating liquid onto a substrate. This liquid processing apparatus includes a substrate holding unit that holds and rotates a substrate, a coating liquid supply unit that applies a coating liquid to the substrate held by the substrate holding unit, a cup unit that is arranged outside the substrate holding unit so as to surround the substrate held by the substrate holding unit, an exhaust path that is provided between the substrate holding unit and the inner peripheral surface of the cup unit, a coating liquid collecting unit that is arranged above the exhaust path so as to cover the exhaust path and has an opening that communicates in the vertical direction, a solvent supply unit that supplies a solvent for the coating liquid to the coating liquid collecting unit, and an intermediary unit that is located above the coating liquid collecting unit and protrudes from the inner peripheral surface of the cup unit toward the coating liquid collecting unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-145561 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology according to the present disclosure prevents clogging of the exhaust path due to foreign matter generated during spin coating processing of a substrate. [Means for solving the problem]

[0005] One aspect of the present disclosure is a liquid processing apparatus that applies a coating liquid onto a substrate, comprising: a substrate holding unit that holds and rotates the substrate; a coating liquid supply unit that applies the coating liquid to the substrate held by the substrate holding unit; and a cup that surrounds the substrate held by the substrate holding unit, wherein the cup has: an outer cup unit arranged outside the substrate holding unit; an inner cup unit arranged on the inner periphery of the outer cup unit and below the substrate holding unit, the inner cup unit having a wall that extends downward; an exhaust path provided between the outer cup unit and the inner cup unit; and a coating liquid collecting unit that has a plurality of openings through which the exhaust flow passes and extends downward below the wall of the inner cup unit with a gap between it and the lower end of the wall; and a solvent supply unit that supplies a solvent for the coating liquid to the coating liquid collecting unit. [Effects of the Invention]

[0006] According to the present disclosure, clogging of the exhaust path due to foreign matter generated during spin coating processing of a substrate can be suppressed. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a longitudinal sectional view showing an outline of the configuration of a resist coating apparatus according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view showing an outline of the configuration of a resist coating apparatus according to an embodiment of the present invention. [Figure 3] FIG. 10 is a cross-sectional view of a cup for explaining a mesh ring. [Figure 4] FIG. [Figure 5] FIG. 10 is a diagram showing a vertical cross section of a cup for explaining a mesh ring. [Figure 6] FIG. 10 is a diagram showing an example of the flow of a solvent supplied to a mesh ring. [Figure 7] FIG. 10 is a vertical cross-sectional view of the cup for explaining the liquid receiving portion. [Figure 8] FIG. 10 is a diagram showing an example of the flow of a solvent supplied to a mesh ring. [Figure 9]10A and 10B are diagrams illustrating an example of the configuration of a liquid receiving section. [Figure 10] FIG. [Figure 11] FIG. 10 is a diagram showing an example of a state in which a solvent remains in an opening. [Figure 12] 10A and 10B are explanatory diagrams illustrating an example of a fixing structure of a mesh ring. [Figure 13] 10 is an explanatory diagram for explaining a mounting portion of a mesh ring and an attachment. FIG. [Figure 14] FIG. 14 is an enlarged view of part A in FIG. [Figure 15] FIG. 10 is a diagram showing an example of the flow of a solvent supplied to a mesh ring. DETAILED DESCRIPTION OF THE INVENTION

[0008] For example, in a photolithography process in a semiconductor device manufacturing process, a coating process is performed in which a predetermined coating liquid is applied onto a semiconductor wafer (hereinafter referred to as a "wafer") as a substrate to form a coating film such as an anti-reflection film or a resist film.

[0009] In the coating process described above, a so-called spin coating method is widely used, in which a coating liquid is supplied from a nozzle to a rotating wafer and the coating liquid is spread on the wafer by centrifugal force to form a coating film on the wafer. Rotary liquid processing apparatuses for performing the spin coating method are provided with a container called a cup to prevent the coating liquid from scattering from the surface of the rotating wafer and scattering to the surrounding area. In such cups, exhaust is performed from the bottom of the cup to prevent contamination of the outside of the cup due to the coating liquid scattering from the edge of the rotating wafer and becoming a mist.

[0010] Recently, there has been a demand for forming a thick coating film on a wafer using a coating liquid such as a highly viscous resist liquid. When using such a highly viscous coating liquid, when the wafer coated with the coating liquid is rotated to spread the coating liquid, the coating liquid may be shaken off from the edge of the wafer and some of it may solidify into threads. Furthermore, since multiple such solidified threads of coating liquid (hereinafter referred to as thread-like foreign matter) are generated during the coating process, these thread-like foreign matter may become entangled with each other and form cotton-like foreign matter.

[0011] There is a concern that these thread-like or cotton-like foreign matter may clog the exhaust path. In particular, the exhaust path near the bottom of the cup has many narrower sections than the exhaust path in the upper part of the cup, making it more susceptible to clogging with the foreign matter. If the exhaust path is clogged with foreign matter, the desired exhaust pressure required to evacuate the inside of the cup cannot be obtained, and for example, the coating liquid may become mist-like and rise to the top of the cup, potentially contaminating the outside of the cup.

[0012] Therefore, the technology according to the present disclosure prevents clogging of the exhaust path due to foreign matter generated during spin coating processing of a substrate.

[0013] Hereinafter, a liquid treatment apparatus according to this embodiment will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0014] 1 and 2 are a longitudinal sectional view and a transverse sectional view, respectively, showing the outline of the configuration of a resist coating apparatus 1 as a liquid processing apparatus. Fig. 3 is a diagram showing a transverse section of a cup 110 for explaining a mesh ring 150 as a coating liquid collecting section. Fig. 4 is a perspective view of the mesh ring 150.

[0015] 1 and 2, the resist coating apparatus 1 has a processing vessel 100 whose interior can be sealed. A loading / unloading port (not shown) for a wafer W serving as a substrate is formed on the side of the processing vessel 100. A spin chuck 101 serving as a substrate holder for holding and rotating the wafer W is provided inside the processing vessel 100. The spin chuck 101 can be rotated at a predetermined speed by a chuck driver 102 such as a motor. The chuck driver 102 is also provided with an elevation drive mechanism such as a cylinder, allowing the spin chuck 101 to be raised and lowered freely.

[0016] A cup 110 that accommodates the spin chuck 101 and is evacuated from the bottom is provided within the processing vessel 100. The cup 110 receives and recovers liquid that splashes or drops from the wafer W. The cup 110 includes an outer cup 120 as an outer cup portion that is disposed outside the spin chuck 101 so as to surround the wafer W held by the spin chuck 101, and an inner cup 130 as an inner cup portion that is located on the inner periphery of the outer cup 120.

[0017] A sidewall 121 serving as a cylindrical wall extending downward is provided at the bottom of the outer cup 120. The inner cup 130 is provided with an annular inclined wall 131 inclined downward from the inner peripheral end to the outer peripheral end, and a sidewall 132 serving as a cylindrical wall extending downward from the outer peripheral end of the inclined wall 131. The inclined wall 131 is disposed below the spin chuck 101 and receives liquid dropping from the wafer W. The sidewall 132 is disposed to face the inner peripheral surface of the sidewall 121 of the outer cup 120, and a gap forming an exhaust path d is formed between the sidewall 121 and the sidewall 132.

[0018] Below the inner cup 130, there are provided an annular horizontal member 141, a cylindrical vertical member 142, and an annular bottom member 143 located at the bottom of the cup 110. Within the cup 110, a space is formed that is surrounded by these members 141, 142, and 143 and the side wall 132 of the inner cup 130. Within this space, there is provided a cylindrical wall portion 145 having an exhaust port 144 that communicates with the exhaust path d. The cylindrical wall portion 145 is disposed so that the exhaust port 144 faces in the vertical direction (height direction), and an exhaust pipe 146 is connected to the bottom member 143 at the lower end of the cylindrical wall portion 145. That is, the exhaust flow within the cup 110 is discharged from the exhaust path d through the cylindrical wall portion 145.

[0019] A drain port 147 for discharging the collected liquid is formed in the bottom member 143 between the side wall 121 of the outer cup 120 and the vertical member 142, and a drain pipe 148 is connected to this drain port 147.

[0020] A mesh ring 150 serving as a coating liquid collector is provided below the side wall 132 of the inner cup 130. This mesh ring 150 collects the resist liquid between the side wall 132 of the inner cup 130 and the bottom member 143. The material of the mesh ring 150 is, for example, a metal such as stainless steel, but is not particularly limited as long as it is a material that is resistant to solvents.

[0021] The mesh ring 150 is fixed to the cup 110 with a gap between the upper end of the mesh ring 150 and the lower end of the side wall 132 of the inner cup 130. The upper limit of the size of this gap can be set arbitrarily as long as it does not impair the function of the mesh ring 150 as a coating liquid collector, and is set to, for example, 10 mm or less. The method for fixing the mesh ring 150 to the cup 110 is not particularly limited, but a preferred fixing method will be described later.

[0022] Furthermore, the position of the outer peripheral surface of the side wall 132 in the radial direction of the cup 110 is approximately the same as the position of the outer peripheral surface of the mesh ring 150. This positional relationship is appropriately changed depending on the shape of the inner cup 130, etc., so that the solvent flowing down along the outer peripheral surface of the inner cup 130 falls onto the mesh ring 150.

[0023] As shown in Figures 3 and 4, mesh ring 150 is a cylindrical component with openings at the top and bottom. As shown in Figure 4, a side wall 151 of mesh ring 150 is provided with a plurality of openings 152 through which the exhaust flow passes. These openings 152 are through-holes that penetrate from the outer peripheral surface to the inner peripheral surface of side wall 151. Furthermore, these openings 152 are formed at intervals along the circumferential direction of side wall 151, and in the example shown in Figures 3 and 4, the openings 152 are arranged in a staggered pattern.

[0024] 5 is a diagram showing a vertical cross section of the cup to explain the mesh ring 150, and the white arrows in FIG. 5 indicate the direction of the exhaust flow. As shown in FIG. 5, the exhaust flow flowing through the exhaust path d passes through the openings 152 of the mesh ring 150 and heads toward the exhaust port 144 (FIG. 1). On the other hand, the resist liquid that flows down along the outer peripheral surface of the inner cup 130 during the resist coating process or the resist liquid that has solidified into threads has difficulty passing through the openings 152 of the mesh ring 150 and remains on the side wall 151. As a result, the resist liquid, which could become cotton-like foreign matter, is collected by the mesh ring 150.

[0025] In this embodiment, mesh ring 150 has a cylindrical shape, but the shape of mesh ring 150 can be changed as appropriate depending on the shape of cup 110. The number, size, arrangement, etc. of openings 152 of mesh ring 150 are determined as appropriate depending on the resist liquid collecting capacity, the exhaust capacity inside cup 110, the shape of cup 110, etc., and a preferred shape of openings 152 will be described later.

[0026] 2, a rail 160 extending in the Y direction (left and right direction in FIG. 2) is formed on the negative X direction side (downward direction in FIG. 2) of the outer cup 120. The rail 160 is formed, for example, from the outside of the negative Y direction side (left direction in FIG. 2) of the outer cup 120 to the outside of the positive Y direction side (right direction in FIG. 2). Two arms 161 and 162 are provided on the rail 160.

[0027] The first arm 161 supports a resist liquid supply nozzle 163 serving as a coating liquid supply unit that supplies a resist liquid as a coating liquid. The resist liquid supplied by the resist liquid supply nozzle 163 has a high viscosity of, for example, 50 cp or more. The first arm 161 is movable on a rail 160 by a nozzle drive unit 164 serving as a movement mechanism. This allows the resist liquid supply nozzle 163 to move from a waiting unit 165 provided outside the outer cup 120 on the positive Y-direction side, passing above the center of the wafer W in the outer cup 120, to a waiting unit 166 provided outside the outer cup 120 on the negative Y-direction side. The nozzle drive unit 164 also allows the first arm 161 to move up and down freely, thereby adjusting the height of the resist liquid supply nozzle 163.

[0028] A solvent supply nozzle 167 that supplies an organic solvent such as thinner onto the wafer W is supported on the second arm 162. The second arm 162 is movable on the rails 160 by a nozzle drive unit 169 serving as a movement mechanism. This allows the solvent supply nozzle 167 to move from a standby unit 168 provided outside the outer cup 120 on the positive Y-direction side to above the center of the wafer W inside the outer cup 120. The standby unit 168 is provided on the positive Y-direction side of the standby unit 165. The nozzle drive unit 169 also allows the second arm 162 to be raised and lowered, allowing the height of the solvent supply nozzle 167 to be adjusted.

[0029] The solvent supplied from the solvent supply nozzle 167 functions as a pre-wet liquid supplied onto the wafer W during a pre-wet process performed before application of the resist liquid to facilitate diffusion of the resist liquid on the wafer W. Furthermore, the solvent from the solvent supply nozzle 167 is shaken off from the wafer W during the pre-wet process and falls into the inner cup 130, and the fallen solvent flows down along the outer peripheral surface of the inner cup 130.

[0030] 1, a back-rinse liquid supply nozzle 170 is provided between the inner cup 130 and the spin chuck 101 to supply an organic solvent such as thinner to the back surface of the wafer W. The solvent supplied from the back-rinse liquid supply nozzle 170 is supplied to the edge of the back side of the wafer W to prevent the solvent from flowing around to the back side of the wafer W when, for example, spreading the resist liquid on the wafer W. The solvent supplied to the back side of the wafer W drops into the inner cup 130 and flows down along the outer peripheral surface of the inner cup 130.

[0031] 6 is a diagram showing an example of the flow of solvent supplied to the mesh ring 150, and the thick arrows in the diagram schematically show the direction of the solvent flow. As shown in Fig. 6, the solvent that flows down along the outer peripheral surface of the inner cup 130 runs down the side wall 132 of the inner cup 130 and falls onto the mesh ring 150. In this way, the solvent is supplied to the mesh ring 150.

[0032] In this way, the solvent flowing down along the outer peripheral surface of the inner cup 130 is supplied to the mesh ring 150, and therefore the means for supplying the solvent to the outer peripheral surface of the inner cup 130 functions as a solvent supply section that supplies the solvent to the mesh ring 150.

[0033] In this embodiment, the above-described solvent supply nozzle 167 and back-rinse liquid supply nozzle 170 function as a solvent supply unit. The solvent supply unit is not limited to these nozzles 167 and 170, and may be, for example, a mechanism that discharges the solvent onto the outer peripheral surface of the inner cup 130 from a solvent discharge hole (not shown) provided inside the inner cup 130. Even in this case, the solvent flowing down along the outer peripheral surface of the inner cup 130 is supplied to the mesh ring 150. In other words, the configuration of the solvent supply unit that supplies the solvent to the mesh ring 150 is not particularly limited.

[0034] As shown in FIG. 1, the resist coating apparatus 1 includes a control unit 200. The control unit 200 is, for example, a computer including a CPU, a memory, and the like, and includes a program storage unit (not shown). The program storage unit stores various programs for controlling a series of resist coating processes for a wafer W in the resist coating apparatus 1. The programs may be recorded on a computer-readable storage medium H and installed from the storage medium H into the control unit 200. The storage medium H may be a temporary storage medium or a non-temporary storage medium. Some or all of the programs may be implemented by dedicated hardware (circuit board).

[0035] The resist coating apparatus 1 according to this embodiment is configured as described above. In this resist coating apparatus 1, the mesh ring 150 disposed below the side wall 132 of the inner cup 130 can collect the resist liquid that flows down along the outer peripheral surface of the inner cup 130 or the resist liquid that has solidified into threads during the resist coating process.

[0036] Then, for example, before or after the resist coating process, the solvent supplied to the wafer W flows down along the outer peripheral surface of the inner cup 130, thereby supplying the solvent to the mesh ring 150. When the solvent supplied to the mesh ring 150 comes into contact with the collected resist liquid or solidified resist liquid, the resist liquid is diluted or the solidified resist liquid dissolves. This makes the resist liquid or solidified resist liquid collected in the mesh ring 150 more likely to be drained, and the resist liquid or solidified resist liquid is discharged from the drain port 147. As a result, clogging of the exhaust path, such as the exhaust port 144 and the exhaust pipe 146, with foreign matter can be suppressed.

[0037] The above has described the general configuration of the resist coating apparatus 1. Next, other configuration examples of the mesh ring 150 will be described.

[0038] (liquid receiving part) 7 is a vertical cross-sectional view of the cup 110 for explaining the liquid receiving portion 153. FIG. 8 is a view showing an example of the flow of the solvent supplied to the mesh ring 150. As shown in FIG.

[0039] 7, the mesh ring 150 preferably has a liquid receiving portion 153 at the upper end of the side wall 151. The liquid receiving portion 153 is a horizontal portion formed in an annular shape, and the outer peripheral end of the liquid receiving portion 153 protrudes outward (toward the outer cup 120) beyond the outer peripheral surface of the side wall 151. In addition, the outer peripheral end of the liquid receiving portion 153 is located further outward than the outer peripheral surface of the side wall 132 of the inner cup 130.

[0040] Note that side wall 151 and liquid receiving portion 153 may be an integral part obtained by integral molding, or may be configured by assembling multiple parts. Liquid receiving portion 153 does not have to have a horizontal shape, but when side wall 151 and liquid receiving portion 153 are molded as a single part by processing a metal plate such as stainless steel, a horizontal shape is preferable from the viewpoint of ease of processing.

[0041] 8, when the liquid receiving portion 153 is provided, the solvent flowing down along the outer peripheral surface of the inner cup 130 falls from the lower end of the side wall 132 into the liquid receiving portion 153. Therefore, even solvent that would not reach the side wall 151 if the liquid receiving portion 153 were not present can be received and collected by the liquid receiving portion 153.

[0042] The solvent that has dropped into the liquid receiving portion 153 flows toward the inner circumferential edge or the outer circumferential edge of the upper surface (liquid receiving surface 153a) of the liquid receiving portion 153. The solvent heading toward the inner circumferential edge of the liquid receiving surface 153a is supplied from the inner circumferential edge to the inner circumferential surface of the side wall 151. On the other hand, the solvent heading toward the outer circumferential edge of the liquid receiving surface 153a flows from the outer circumferential edge down the lower surface of the liquid receiving portion 153 and is supplied to the outer circumferential surface of the side wall 151.

[0043] In this way, when the mesh ring 150 has the liquid receiving portion 153, it is possible to collect a larger amount of the solvent flowing down along the outer peripheral surface of the inner cup 130 and supply it to the mesh ring 150. This promotes dilution of the resist liquid collected in the mesh ring 150 or dissolution of solidified resist liquid, thereby enhancing the effect of suppressing clogging of the exhaust path with foreign matter.

[0044] The shape of liquid receiving portion 153 is not limited to the L-shape shown in Fig. 8, and may be, for example, a T-shape. Meanwhile, while the inside of cup 110 is being evacuated, an exhaust flow is formed in a direction from the outer periphery side to the inner periphery side of mesh ring 150 (from left to right in Fig. 8). Therefore, when liquid receiving portion 153 is T-shaped, the solvent running along the inner periphery end of liquid receiving portion 153 may be affected by the exhaust flow and have difficulty reaching side wall 151.

[0045] 8, when the outer peripheral edge of the liquid receiving portion 153 protrudes outward beyond the side wall 132 of the inner cup 130, it is preferable that the inner peripheral edge of the liquid receiving portion 153 and the inner peripheral surface of the side wall 151 are continuous without any steps. This makes it easier for the solvent to be supplied from the inner peripheral edge of the liquid receiving portion 153 to the side wall 151 compared to a T-shaped liquid receiving portion.

[0046] The shape of the liquid receiving portion 153 may be, for example, any of the shapes shown in FIGS. 9(a) to 9(d).

[0047] 9(a) shows an example in which the outer peripheral edge of the liquid receiving portion 153 and the outer peripheral surface of the side wall 151 are connected by an inclined surface 153b. In the liquid receiving portion 153 shown in FIG. 8 described above, as indicated by the dotted arrow in FIG. 8, some of the solvent may fall from the outer peripheral edge of the liquid receiving portion 153, preventing the solvent from being supplied to the side wall 151. On the other hand, with the liquid receiving portion 153 having the inclined surface 153b shown in FIG. 9(a), the solvent flowing down from the outer peripheral edge of the liquid receiving surface 153a is more likely to flow along the inclined surface 153b, thereby increasing the amount of solvent supplied to the side wall 151.

[0048] 9(b) shows an example in which a side wall 154 extending upward from the liquid receiving portion 153 is provided at the outer peripheral end of the liquid receiving portion 153. The side wall 154 is a cylindrical wall body, and the solvent flowing down along the outer peripheral surface of the inner cup 130 falls onto a liquid receiving surface 153a located on the inner peripheral side of the side wall 154. The solvent that falls onto the liquid receiving surface 153a does not fall from the outer peripheral end of the liquid receiving surface 153a due to the presence of the side wall 154, but flows toward the inner peripheral end of the liquid receiving surface 153a. In other words, with the liquid receiving portion 153 shown in FIG. 9(b), the solvent that does not fall from the outer peripheral end of the liquid receiving surface 153a can also be supplied to the side wall 151.

[0049] 9(c) shows an example in which the outer peripheral edge of the liquid receiving surface 153a is higher than the inner peripheral edge, and the liquid receiving surface 153a is inclined downward from the outer peripheral edge toward the inner peripheral edge. With the liquid receiving portion 153 shown in FIG. 9(c), the solvent that falls onto the liquid receiving surface 153a flows down toward the inner peripheral edge of the liquid receiving surface 153a, but is less likely to fall from the outer peripheral edge of the liquid receiving surface 153a. This makes it possible to increase the amount of solvent supplied from the liquid receiving surface 153a of the mesh ring 150 toward the inner peripheral surface of the side wall 151.

[0050] 9(d) shows an example in which the outer peripheral edge of the liquid receiving surface 153a is lower than the inner peripheral edge, and the liquid receiving surface 153a is inclined upward from the outer peripheral edge toward the inner peripheral edge. With the liquid receiving portion 153 shown in FIG. 9(d), the solvent that falls onto the liquid receiving surface 153a flows downward toward the outer peripheral edge of the liquid receiving surface 153a, but is less likely to fall from the inner peripheral edge of the liquid receiving surface 153a. This makes it possible to increase the amount of solvent supplied from the liquid receiving surface 153a of the mesh ring 150 toward the outer peripheral surface of the side wall 151.

[0051] (Example of opening shape) Next, a description will be given of other examples of the shape of the opening 152. FIG.

[0052] 10 is rectangular, with its short sides positioned at the upper and lower ends of the opening 152. The openings 152 extend from the upper end to the lower end of the side wall 151 of the mesh ring 150, and the openings 152 are spaced apart along the circumferential direction of the mesh ring 150.

[0053] When the opening 152 has such a shape, it is possible to prevent the opening 152 from being blocked by the solvent supplied to the mesh ring 150, and it is possible to easily maintain a desired exhaust pressure during evacuation inside the cup. The reason for this will be explained below with reference to FIG. 11.

[0054] FIG. 11 is a diagram showing an example of the state of solvent remaining in the opening 152, and the black circles in the diagram schematically show the solvent remaining in the opening 152.

[0055] The solvent supplied to the mesh ring 150 may not be drained but remain attached to the side wall 151 or the openings 152 of the mesh ring 150. In this case, as shown in FIG. 11( a), if the upper end shape of the openings 152 is not horizontal, such as an oval or circular shape, a liquid film of the solvent is likely to form at the openings 152 when the solvent flowing from above to below the side wall 151 passes through the openings 152.

[0056] Even if some openings 152a are blocked by the liquid film, some openings 152b remain open without a liquid film, allowing the resist coating process described above. However, the presence of blocked openings 152a relatively reduces the number of openings 152b through which the exhaust flow can pass, making it difficult to maintain a desired exhaust pressure during cup exhaust. Therefore, in order to perform the resist coating process while maintaining the exhaust capacity within the cup within an acceptable range, it is necessary to increase the frequency of maintenance to remove the liquid film from the blocked openings 152a.

[0057] 11(b), if the upper end of the opening 152 is horizontal, it is difficult for a liquid film to form that blocks the opening 152. For this reason, it is preferable that the upper end of the opening 152 is formed horizontally.

[0058] 11(b), it is preferable that the opening 152 is rectangular, with its shorter sides positioned at the upper and lower ends of the opening 152. This can further suppress the formation of a liquid film by the solvent supplied to the mesh ring 150.

[0059] On the other hand, when multiple rectangular openings 152 are arranged in the height direction of the mesh ring 150 as shown in Figure 11(b), droplets of solvent may form in each of the openings 152 lined up in the height direction.

[0060] For this reason, it is preferable that the rectangular openings 152 extend from the upper end to the lower end of the side wall 151 of the mesh ring 150, as shown in the above-mentioned Figures 10 and 11(c). This reduces the number of openings 152 lined up in the height direction, and reduces the number of locations where solvent droplets are likely to form. As a result, even if solvent droplets form in the openings 152, it is possible to prevent a decrease in the opening area of ​​the entire mesh ring 150. Therefore, even if the maintenance frequency of the mesh ring 150 is reduced, it is possible to easily maintain a desired exhaust pressure.

[0061] (Mesh ring fixing) Next, an example of a method for fixing the mesh ring 150 will be described.

[0062] Fig. 12 is an explanatory diagram illustrating the fixing structure of the mesh ring 150, showing a partial cross section of the fixing structure. Fig. 13 is an explanatory diagram illustrating the attachment portion of the mesh ring 150 and the attachment 180. Fig. 14 is an enlarged view of part A in Fig. 13. Fig. 15 is a diagram showing an example of the flow of solvent supplied to the mesh ring 150, with thick arrows in the diagram schematically indicating the direction of solvent flow.

[0063] 12, mesh ring 150 is fixed to cylindrical wall portion 145 via attachment 180. Attachment 180 has an annular upper surface portion 181 and a side wall portion 182 extending downward from the outer circumferential edge of upper surface portion 181. The material of attachment 180 is, for example, a metal such as stainless steel, but is not particularly limited as long as it is a material that is resistant to solvents.

[0064] When attaching this attachment 180 to the cylindrical wall portion 145, by placing the attachment 180 over the upper end portion of the cylindrical wall portion 145, the upper surface portion 181 comes into contact with the upper surface of the cylindrical wall portion 145 and the inner peripheral surface of the side wall portion 182 comes into contact with the outer peripheral surface of the cylindrical wall portion 145. In other words, the attachment 180 has a shape that fits into the upper end portion of the cylindrical wall portion 145 and is configured to be detachable from the upper end portion of the cylindrical wall portion 145.

[0065] 13 and 14, the side wall portion 182 is provided with an attachment portion 183 that protrudes outward from the outer peripheral surface of the side wall portion 182 and that is used to attach the mesh ring 150. The attachment portion 183 is provided at the lower end of the side wall portion 182, and therefore the upper surface of the attachment portion 183 is located lower than the upper end of the side wall portion 182. The attachment portion 183 is formed at two locations spaced apart in the circumferential direction of the side wall portion 182.

[0066] On the inner circumferential surface of mesh ring 150, bracket portion 155 is provided as a mounting portion for mounting attachment 180, formed at the same interval as the two mounting portions 183. Bracket portion 155 has a wall body 156 extending downward from the inner circumferential surface of the upper end portion of side wall 151, and a horizontal wall body 157 protruding inward from the lower end portion of wall body 156. In other words, bracket portion 155 is formed in an L shape by wall body 156 and wall body 157.

[0067] When attaching the attachment 180 to the mesh ring 150, the mounting portion 183 of the attachment 180 is placed on the wall body 157 of the bracket portion 155, and they are fixed to each other with bolts 184 serving as fasteners. Then, the attachment 180 to which the mesh ring 150 is attached is placed over the upper end of the cylindrical wall portion 145 (FIG. 12), thereby fixing the mesh ring 150 to the cylindrical wall portion 145.

[0068] With the structure in which the mesh ring 150 is fixed to the cylindrical wall portion 145 as described above, the mesh ring 150 can be attached not only when a new resist coating apparatus 1 is manufactured, but also to an existing resist coating apparatus that does not have the mesh ring 150.

[0069] Furthermore, if the mesh ring 150 is detachably fixed to the cylindrical wall portion 145, it is easy to perform maintenance such as replacing or cleaning the mesh ring 150. In addition, it becomes possible to share the mesh ring 150 among a plurality of resist coating devices.

[0070] In addition, in the above-described method of fixing mesh ring 150, the solvent that drops into liquid receiving portion 153 flows onto side wall 151, while at the location where bracket portion 155 is formed, the solvent flows from liquid receiving portion 153 to bracket portion 155, as shown in Fig. 15. The solvent that has flowed into bracket portion 155 then flows along walls 156 and 157, drops from wall 157, and is drained. That is, because the attachment portion between mesh ring 150 and attachment 180 is located at a position lower than the upper end of attachment 180, the solvent that has flowed from mesh ring 150 toward attachment 180 can be prevented from flowing into exhaust port 144 (Fig. 12).

[0071] The method for fixing the mesh ring 150 to the cylindrical wall portion 145 via the attachment 180 has been described above.

[0072] It is preferable that mesh ring 150 is fixed to cup 110 so as not to come into contact with it, except for the fixing portion (attachment 180 in the example of FIG. 12) with cylindrical wall portion 145. This prevents the resist liquid from accumulating between mesh ring 150 and cup 110, and prevents the components from sticking together due to solidification of the resist liquid.

[0073] In particular, if mesh ring 150 and bottom member 143 (FIG. 1) of cup 110 are not in contact with each other, resist liquid diluted with a solvent or a solution of thread-like or cotton-like foreign matter dissolved in a solvent can be easily drained.

[0074] Furthermore, the mesh ring 150 and the cylindrical wall portion 145 may be fixed without providing the attachment 180. In this case, it is preferable that the fixing portion (not shown) between the mesh ring 150 and the cylindrical wall portion 145 is located at a position lower than the upper end of the cylindrical wall portion 145. This makes it easier for the solvent that flows into the fixing portion between the mesh ring 150 and the cylindrical wall portion 145 to be drained without exceeding the upper end of the cylindrical wall portion 145, and prevents the solvent from flowing into the exhaust port 144.

[0075] The liquid processing apparatus according to the present disclosure has been described above using the resist coating apparatus 1 as an example. Note that the liquid processing apparatus according to the present disclosure can also be applied to liquid processing apparatuses for processing substrates other than semiconductor wafers, such as FPD (flat panel display) substrates and mask reticles for photomasks.

[0076] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope of the appended claims, the technical scope of the present disclosure, and the spirit thereof. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, as well as other functions and effects that would be apparent to a person skilled in the art from the description herein.

[0077] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that would be apparent to a person skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0078] Note that the following configuration examples also fall within the technical scope of the present disclosure. (1) A liquid processing apparatus for applying a coating liquid onto a substrate, a substrate holder that holds and rotates the substrate; a coating liquid supply unit that applies the coating liquid to the substrate held by the substrate holding unit; a cup surrounding the substrate held by the substrate holder, The cup is an outer cup portion disposed outside the substrate holder; an inner cup portion disposed on the inner periphery of the outer cup portion and below the substrate holding portion, the inner cup portion having a wall extending downward; an exhaust path provided between the outer cup portion and the inner cup portion; a coating liquid collecting section provided with a plurality of openings through which an exhaust flow passes, the coating liquid collecting section extending downward below the wall of the inner cup section with a gap between it and a lower end of the wall, a liquid treatment apparatus including a solvent supplying section that supplies a solvent for the coating liquid to the coating liquid collecting section; (2) The liquid processing apparatus according to (1), further comprising a liquid receiving section at an upper end of the coating liquid collecting section for receiving the solvent dropping from the wall body. (3) The liquid treatment device according to (2), wherein the liquid receiving portion protrudes outward beyond the outer peripheral surface of the wall body. (4) A liquid treatment device according to (2) or (3), wherein the liquid receiving portion has a horizontal shape. (5) The liquid treatment device according to any one of (1) to (4), wherein the upper end of the opening has a horizontal shape. (6) The liquid treatment device according to any one of (1) to (5), wherein the opening is rectangular, and the shorter sides are located at the upper and lower ends of the opening. (7) The plurality of openings extend from an upper end to a lower end of the coating liquid collecting portion, The liquid processing device according to any one of (1) to (6), wherein the openings are arranged at intervals along the circumferential direction of the coating liquid collecting section. (8) A cylindrical wall portion is provided below the inner cup portion and has an exhaust port communicating with the exhaust path, The liquid processing apparatus according to any one of (1) to (7), wherein the coating liquid collecting section is fixed to the cylindrical wall section. (9) The liquid processing apparatus according to (8), wherein the coating liquid collecting section is not in contact with the cup except for a portion where the coating liquid collecting section is fixed to the cylindrical wall section. [Explanation of symbols]

[0079] 1. Resist coating device 101 Spin Chuck 110 cups 120 outer cup 130 Inner cup 132 Side wall 150 mesh ring 152 Opening 163 Resist liquid supply nozzle 167 Solvent supply nozzle 170 Back rinse liquid supply nozzle d Exhaust route W wafer

Claims

1. A liquid processing apparatus that applies a coating liquid onto a substrate, a substrate holder that holds and rotates the substrate; a coating liquid supply unit that applies the coating liquid to the substrate held by the substrate holding unit; a cup surrounding the substrate held by the substrate holder, The cup is an outer cup portion disposed outside the substrate holder; an inner cup portion disposed on the inner periphery of the outer cup portion and below the substrate holding portion, the inner cup portion having a wall extending downward; an exhaust path provided between the outer cup portion and the inner cup portion; a coating liquid collecting section provided with a plurality of openings through which an exhaust flow passes, the coating liquid collecting section extending downward below the wall of the inner cup section with a gap between it and a lower end of the wall, a liquid treatment apparatus including a solvent supplying section that supplies a solvent for the coating liquid to the coating liquid collecting section;

2. The liquid treatment apparatus according to claim 1 , further comprising a liquid receiving portion at an upper end of the coating liquid collecting portion, the liquid receiving portion receiving the solvent dropping from the wall body.

3. The liquid treatment apparatus according to claim 2 , wherein the liquid receiving portion protrudes outward beyond an outer peripheral surface of the wall body.

4. The liquid treatment device according to claim 3 , wherein the liquid receiving portion has a horizontal shape.

5. 5. The liquid treatment apparatus according to claim 1, wherein an upper end of the opening has a horizontal shape.

6. 5. The liquid treatment apparatus according to claim 1, wherein the opening is rectangular, and the shorter sides of the opening are located at the upper and lower ends of the opening.

7. the plurality of openings extend from an upper end to a lower end of the coating liquid collecting portion, The liquid treatment device according to claim 6 , wherein the openings are arranged at intervals along the circumferential direction of the coating liquid collecting portion.

8. a cylindrical wall portion provided below the inner cup portion and having an exhaust port communicating with the exhaust path; 5. The liquid treatment apparatus according to claim 1, wherein the coating liquid collecting section is fixed to the cylindrical wall section.

9. The liquid processing apparatus according to claim 8 , wherein the coating liquid collecting portion is not in contact with the cup except for a portion where the coating liquid collecting portion is fixed to the cylindrical wall portion.

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