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; a cylindrical wall portion provided below the inner cup portion and having an upwardly-opened exhaust port communicating with the exhaust path; and a coating liquid collector arranged 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. The coating liquid collector is fixed to the cylindrical wall portion.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a liquid processing apparatus.

Background Art

[0002] Patent Document 1 discloses a liquid processing apparatus that applies a coating liquid onto a substrate. This liquid processing apparatus includes a substrate holding unit that holds and rotates the substrate, a coating liquid supply unit that supplies the coating liquid to the substrate held by the substrate holding unit, a cup unit disposed outside the substrate holding unit so as to surround the substrate held by the substrate holding unit, an exhaust path provided between the substrate holding unit and the inner peripheral surface of the cup unit, a coating liquid collection unit provided above the exhaust path so as to cover the exhaust path and having an opening communicating in the vertical direction, a solvent supply unit that supplies a solvent of the coating liquid to the coating liquid collection unit, and a relay unit located above the coating liquid collection unit and protruding from the inner peripheral surface of the cup unit toward the coating liquid collection unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology according to the present disclosure suppresses clogging of the exhaust path due to foreign matter generated during the spin coating process of the substrate.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a liquid processing apparatus that applies a coating liquid onto a substrate, including a substrate holding unit that holds and rotates the substrate, The aforementionedThe device comprises a coating liquid supply unit for applying the coating liquid to the substrate held in the substrate holding unit, and a cup surrounding the substrate held in the substrate holding unit, wherein the cup has an outer cup portion located outside the substrate holding unit, an inner cup portion located on the inner circumference of the outer cup portion and below the substrate holding unit and having a wall extending downward, an exhaust path provided between the outer cup portion and the inner cup portion, a cylindrical wall portion located below the inner cup portion and communicating with the exhaust path, having an upward-opening exhaust port, and a coating liquid collection portion located below the wall portion of the inner cup portion with a gap between it and the lower end of the wall portion, and a solvent supply unit for supplying the solvent of the coating liquid to the coating liquid collection portion, the coating liquid collection portion being fixed to the cylindrical wall portion. The fixing portion between the coating liquid collection portion and the cylindrical wall portion is located below the upper end of the cylindrical wall portion, the cylindrical wall portion has a cylindrical main body portion and an attachment member detachably attached to the main body portion, the coating liquid collection portion is attached to the attachment member, and the fixing portion is the fixing portion between the coating liquid collection portion and the attachment member. . [Effects of the Invention]

[0006] According to this disclosure, it is possible to suppress clogging of the exhaust path due to foreign matter generated during the rotary coating process of the substrate. [Brief explanation of the drawing]

[0007] [Figure 1] This is a longitudinal cross-sectional view showing a schematic configuration of the resist coating apparatus according to this embodiment. [Figure 2] This is a cross-sectional view showing a schematic configuration of the resist coating apparatus according to this embodiment. [Figure 3] This figure shows a cross-section of a cup used to illustrate a cylindrical mesh ring. [Figure 4] This is a perspective view of a cylindrical mesh ring. [Figure 5] This figure shows a longitudinal cross-section of a cup to illustrate a cylindrical mesh ring. [Figure 6] This figure shows an example of the flow of solvent supplied to a cylindrical mesh ring. [Figure 7] This is an explanatory diagram illustrating an example of a fixing structure for a cylindrical mesh ring. [Figure 8] This is an explanatory diagram illustrating the fixing mechanism of the cylindrical mesh ring and attachment. [Figure 9] It is an enlarged view of part A in FIG. 8. [Figure 10] It is a diagram showing an example of the flow of the solvent supplied to the cylindrical mesh ring. [Figure 11] It is a diagram showing a longitudinal section of a cup for explaining the liquid receiving part applied to the cylindrical mesh ring. [Figure 12] It is a diagram showing an example of the flow of the solvent supplied to the cylindrical mesh ring. [Figure 13] It is a diagram showing a configuration example of the liquid receiving part applied to the cylindrical mesh ring. [Figure 14] It is a perspective view of the mesh ring for explaining another shape example of the opening in the cylindrical mesh ring. [Figure 15] It is a diagram showing an example of the residual state of the solvent in the opening. [Figure 16] It is a diagram showing a longitudinal section of a cup for explaining the annular mesh ring. [Figure 17] It is a diagram showing a cross section of a cup for explaining the annular mesh ring. [Figure 18] It is a diagram showing an example of the flow of the solvent supplied to the annular mesh ring. [Figure 19] It is an explanatory diagram showing the vicinity of the fixing part of the annular mesh ring and the attachment. [Figure 20] It is an explanatory diagram for explaining another shape example of the annular mesh ring. [Figure 21] It is a diagram showing a cross section of a cup for explaining the annular plate. [Figure 22] It is a diagram showing an example of the flow of the solvent supplied to the annular plate.

Embodiments for Carrying Out the Invention

[0008] For example, in the photolithography process in the manufacturing process of semiconductor devices, a coating process is performed to form a coating film such as an antireflection film or a resist film by applying a predetermined coating liquid onto a semiconductor wafer (hereinafter referred to as "wafer") as a substrate.

[0009] In the above-described coating process, a so-called spin coating method is widely used, in which the coating liquid is supplied from a nozzle to the rotating wafer, and the coating liquid is diffused on the wafer by centrifugal force to form a coating film on the wafer. In a rotary liquid processing apparatus for performing the spin coating method, a container called a cup is provided to prevent the coating liquid scattered from the surface of the rotating wafer from scattering around. In such a cup, exhaust is performed from the bottom of the cup so as not to contaminate the outside of the cup due to the upward movement of the coating liquid scattered from the edge of the rotating wafer and becoming mist-like.

[0010] By the way, in recent years, there are cases where it is required to form a coating film with a large film thickness on a wafer using a coating liquid such as a high-viscosity resist liquid. When using such a high-viscosity coating liquid, when rotating the wafer coated with the coating liquid to diffuse the coating liquid, the coating liquid may be shaken off from the edge of the wafer and partially solidify in a filamentous form. And since a plurality of such filamentously solidified coating liquids (hereinafter referred to as filamentous foreign matters) are generated in the process of performing the coating process, these filamentous foreign matters may be intertwined with each other and become cotton-like foreign matters.

[0011] There is a concern that these filamentous or cotton-like foreign matters may clog the exhaust path. In particular, the exhaust path near the bottom in the cup has more narrow parts than the exhaust path in the upper part of the cup, so the above-mentioned foreign matters are likely to clog. When the exhaust path is clogged by foreign matters, a desired exhaust pressure required for performing exhaust in the cup cannot be obtained. For example, the coating liquid in a mist form may rise above the cup, and there is a risk of contaminating the outside of the cup.

[0012] Therefore, the technology according to the present disclosure suppresses clogging of the exhaust path by foreign matters generated during the spin coating process of the substrate.

[0013] The liquid processing apparatus according to this embodiment will be described below with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant explanations will be omitted.

[0014] Figures 1 and 2 are longitudinal and transverse cross-sectional views, respectively, illustrating the configuration of the resist coating apparatus 1 as a liquid processing apparatus. Figure 3 is a cross-sectional view of the cup 110 illustrating the mesh ring 150 as a coating liquid collection section. Figure 4 is a perspective view of the mesh ring 150.

[0015] As shown in Figures 1 and 2, the resist coating apparatus 1 has a processing container 100 whose interior can be sealed. An inlet / outlet (not shown) for loading and unloading wafers W as substrates is formed on the side of the processing container 100. A spin chuck 101 is provided inside the processing container 100 as a substrate holding part for holding and rotating the wafers W. The spin chuck 101 can be rotated at a predetermined speed by a chuck drive unit 102, such as a motor. The chuck drive unit 102 is also provided with a lifting drive mechanism, such as a cylinder, so that the spin chuck 101 can move up and down.

[0016] Furthermore, the processing container 100 is provided with a cup 110 that houses the spin chuck 101 and exhausts air from the bottom. The cup 110 is for receiving and collecting liquid that is scattered or dropped from the wafer W. The cup 110 includes an outer cup 120, which is positioned outside the spin chuck 101 so as to surround the wafer W held by the spin chuck 101, and an inner cup 130, which is positioned on the inner circumference side of the outer cup 120.

[0017] The lower part of the outer cup 120 is provided with a side wall 121, which is a cylindrical wall extending downward. The inner cup 130 is provided with an annular inclined wall 131 that slopes downward from the inner circumference to the outer circumference, and a side wall 132, which is a cylindrical wall extending downward from the outer circumference of the inclined wall 131. The inclined wall 131 is positioned below the spin chuck 101 and receives the liquid falling from the wafer W. The side wall 132 is positioned opposite the inner circumference of the side wall 121 of the outer cup 120, and a gap forming an exhaust path d is formed between the side wall 121 and the side wall 132.

[0018] Below the inner cup 130, there is an annular horizontal member 141, a cylindrical vertical member 142, and an annular bottom member 143 located at the bottom of the cup 110. Inside the cup 110, a space is formed surrounded by these members 141, 142, 143 and the side wall 132 of the inner cup 130 described above. Within this space, there is a cylindrical wall portion 145 having an exhaust port 144 that communicates with the exhaust path d.

[0019] The cylindrical wall portion 145 extends vertically (in the height direction) of the cup 110, and the exhaust port 144 opens upward. An exhaust pipe 146 is connected to the bottom surface member 143 at the lower end of the cylindrical wall portion 145. In other words, the exhaust flow inside the cup 110 is discharged through the exhaust path d via the cylindrical wall portion 145.

[0020] 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.

[0021] A mesh ring 150 is provided below the side wall 132 of the inner cup 130, serving as a coating liquid collection section. 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 has chemical resistance to solvents.

[0022] The mesh ring 150 is fixed to the cup 110 with a gap between its upper end and the lower end of the side wall 132 of the inner cup 130. The upper limit of this gap can be arbitrarily set within a range that does not impair the function of the mesh ring 150 as a coating liquid collection part, and can be set to, for example, 10 mm or less. The method of fixing the mesh ring 150 to the cup 110 will be described later.

[0023] Furthermore, the position of the outer surface of the side wall 132 of the cup 110 in the radial direction and the position of the outer surface of the mesh ring 150 are approximately the same. These positional relationships are appropriately changed according to the shape of the inner cup 130, etc., so that the solvent flowing down along the outer surface of the inner cup 130 falls onto the mesh ring 150.

[0024] As shown in Figures 3 and 4, the mesh ring 150 is a cylindrical component, such as a cylindrical shape, with an open top and bottom. As shown in Figure 4, the side wall 151 of the 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 circumferential surface to the inner circumferential surface of the side wall 151. Furthermore, these openings 152 are formed at intervals along the circumferential direction of the side wall 151, and in the example shown in Figures 3 and 4, the openings 152 are arranged in a staggered pattern.

[0025] Figure 5 is a diagram showing a longitudinal cross-section of the cup to illustrate the mesh ring 150, and the white arrows in Figure 5 indicate the direction of the exhaust flow. As shown in Figure 5, the exhaust flow flowing through the exhaust path d passes through the opening 152 of the mesh ring 150 and heads toward the exhaust port 144 (Figure 1). On the other hand, the resist liquid that flows down along the outer surface of the inner cup 130 during the resist coating process, or the resist liquid that has solidified into a thread-like form, has difficulty passing through the opening 152 of the mesh ring 150 and remains on the side wall 151. As a result, the resist liquid that could become cotton-like foreign matter is collected by the mesh ring 150.

[0026] In this embodiment, the mesh ring 150 is cylindrical, but the shape of the mesh ring 150 can be appropriately changed according to the shape of the cup 110. In addition, the number, size, and arrangement of the openings 152 of the mesh ring 150 can be appropriately determined according to the resist liquid collection capacity, the exhaust capacity of the cup 110, the shape of the cup 110, etc.

[0027] As shown in Figure 2, a rail 160 extending along the Y direction (left-right direction in Figure 2) is formed on the negative X direction (downward direction in Figure 2) side of the outer cup 120. The rail 160 is formed, for example, from the outer side of the negative Y direction (left direction in Figure 2) side of the outer cup 120 to the outer side of the positive Y direction (right direction in Figure 2) side. Two arms 161 and 162 are provided on the rail 160.

[0028] The first arm 161 supports a resist liquid supply nozzle 163, which serves as a coating liquid supply unit for supplying resist liquid as a coating liquid. The resist liquid supplied by the resist liquid supply nozzle 163 has a high viscosity, for example, 50 cp or more. The first arm 161 is movable on the rail 160 by a nozzle drive unit 164, which serves as a moving mechanism. As a result, the resist liquid supply nozzle 163 can move from a standby unit 165 located on the outside of the outer cup 120 on the positive Y-direction side, through the area above the center of the wafer W inside the outer cup 120, to a standby unit 166 located on the outside of the outer cup 120 on the negative Y-direction side. Furthermore, the nozzle drive unit 164 allows the first arm 161 to be raised and lowered, and the height of the resist liquid supply nozzle 163 can be adjusted.

[0029] A solvent supply nozzle 167, which 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 rail 160 by a nozzle drive unit 169, which acts as a moving mechanism. This allows the solvent supply nozzle 167 to move from a standby unit 168, which is located on the outside of 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 located on the positive Y-direction side of the standby unit 165. Furthermore, the nozzle drive unit 169 allows the second arm 162 to be raised and lowered, and the height of the solvent supply nozzle 167 can be adjusted.

[0030] The solvent supplied from the solvent supply nozzle 167 functions as a pre-wetting liquid supplied onto the wafer W during the pre-wetting process, which is performed before coating the resist solution, to facilitate the diffusion of the resist solution on the wafer W. The solvent from the solvent supply nozzle 167 is also shaken off the wafer W during the pre-wetting process and falls into the inner cup 130, where it flows down along the outer surface of the inner cup 130.

[0031] Furthermore, as shown in Figure 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 back edge of the wafer W to prevent it from flowing to the back side of the wafer W when the resist liquid is diffused onto the wafer W. The solvent supplied to the back side of the wafer W falls into the inner cup 130 and flows down along the outer surface of the inner cup 130.

[0032] Figure 6 shows an example of the solvent flow supplied to the mesh ring 150, where the thick arrows schematically indicate the direction of solvent flow. As shown in Figure 6, the solvent that flows down along the outer surface of the inner cup 130 travels along the side wall 132 of the inner cup 130 and falls onto the mesh ring 150. This supplies the solvent to the mesh ring 150.

[0033] In this way, the solvent flowing down along the outer surface of the inner cup 130 is supplied to the mesh ring 150, so the means for supplying the solvent to the outer surface of the inner cup 130 functions as a solvent supply unit that supplies the solvent to the mesh ring 150.

[0034] In this embodiment, the solvent supply nozzle 167 and the back rinse liquid supply nozzle 170 described above function as a solvent supply unit. The solvent supply unit is not limited to these nozzles 167 and 170, but may also be a mechanism that discharges solvent from a solvent discharge hole (not shown) provided inside the inner cup 130 to the outer circumferential surface of the inner cup 130. In this case as well, the solvent flowing down along the outer circumferential 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 solvent to the mesh ring 150 is not particularly limited.

[0035] As shown in Figure 1, the resist coating apparatus 1 includes a control unit 200. The control unit 200 is a computer equipped with, for example, a CPU and memory, and has a program storage unit (not shown). The program storage unit stores various programs that control a series of resist coating processes on the wafer W in the resist coating apparatus 1. The above programs may have been recorded on a storage medium H readable by the computer and installed from the storage medium H to the control unit 200. The storage medium H may be a temporary or permanent storage medium. Part or all of the programs may be implemented on dedicated hardware (circuit board).

[0036] (Securing the mesh ring) Next, we will explain how to secure the mesh ring 150.

[0037] Figure 7 is an explanatory diagram illustrating the fixing structure of the mesh ring 150, showing a partial cross-section of the fixing structure. Figure 8 is an explanatory diagram illustrating the fixing part of the mesh ring 150 and attachment 180. Figure 9 is an enlarged view of part A in Figure 8. Figure 10 is a diagram showing an example of the flow of solvent supplied to the mesh ring 150, where the thick arrows schematically indicate the direction of solvent flow.

[0038] As shown in Figure 7, the cylindrical wall portion 145 is composed of a cylindrical main body portion 145a and an attachment 180 which is a mounting member that is detachably attached to the upper end of the main body portion 145a. The attachment 180 has an annular upper surface portion 181 and a side wall portion 182 that extends downward from the outer peripheral end of the upper surface portion 181.

[0039] The material of the attachment 180 is not particularly limited as long as it is a material that has chemical resistance to solvents, such as a metal like stainless steel, but it is preferable to use resin. By forming the attachment 180 from resin, the flexibility of the attachment 180 is increased, making it easier to remove from the main body 145a.

[0040] The attachment 180 has a shape in which the upper surface portion 181 is in contact with the upper surface of the main body portion 145a, and the inner circumferential surface of the side wall portion 182 is in contact with the outer circumferential surface of the main body portion 145a. In other words, the attachment 180 has a shape that fits onto the upper end of the main body portion 145a and is configured to be detachably attached to the upper end of the main body portion 145a. Note that the form of "attaching the attachment 180 to the main body portion 145a" in this specification also includes the form in which the attachment 180 is fitted onto the main body portion 145a as described above.

[0041] As shown in Figures 8 and 9, the side wall portion 182 is provided with fixing portions 183 for attaching the mesh ring 150, which protrude outward from the outer circumferential surface of the side wall portion 182. Since these fixing portions 183 are provided at the lower end of the side wall portion 182, the upper surface of the fixing portion 183 is lower than the upper surface portion 181. In addition, two fixing portions 183 are formed at intervals along the circumferential direction of the side wall portion 182.

[0042] The inner circumferential surface of the mesh ring 150 is provided with bracket portions 155, which serve as fixing portions for attaching the attachment 180, and are formed at the same intervals as the two fixing portions 183 described above. The bracket portion 155 has a wall body 156 extending downward from the inner circumferential surface of the upper end of the side wall 151, and a horizontal wall body 157 projecting inward from the lower end of the wall body 156. In other words, the bracket portion 155 has an L-shaped vertical cross-section formed by the wall body 156 and the wall body 157.

[0043] When attaching the attachment 180 to the mesh ring 150, the fixing portion 183 of the attachment 180 is placed on the wall 157 of the bracket portion 155, and the two parts are detachably fixed together by fastening with a bolt 184 which serves as a fastener. Note that the fastener is not limited to a bolt 184, but may be other parts such as a hook.

[0044] Then, by placing the attachment 180, to which the mesh ring 150 is attached, over the upper end of the main body portion 145a (Figure 7), the mesh ring 150 is detachably fixed to the cylindrical wall portion 145.

[0045] The method for fixing the mesh ring 150 to the cylindrical wall portion 145 has been described above.

[0046] In the resist coating apparatus 1 according to this embodiment, a mesh ring 150 positioned below the side wall 132 of the inner cup 130 can collect the resist liquid that flows down along the outer surface of the inner cup 130 or the resist liquid that has solidified into a thread-like form during the resist coating process.

[0047] Subsequently, the solvent supplied to the wafer W, for example, before or after the resist coating process, flows down along the outer surface of the inner cup 130, thereby supplying the solvent to the mesh ring 150. The solvent supplied to the mesh ring 150 then comes into contact with the resist liquid or solidified resist liquid collected in the mesh ring 150, resulting in dilution of the resist liquid or dissolution of the solidified resist liquid. This makes the resist liquid or solidified resist liquid collected in the mesh ring 150 easier to drain, and facilitates discharge from the drain port 147. As a result, clogging of the exhaust path, such as the exhaust port 144 or exhaust pipe 146, can be suppressed.

[0048] Furthermore, the structure in which the mesh ring 150 is fixed to the cylindrical wall portion 145 makes it easier to attach and detach the mesh ring 150 in a cup with a general structure, improving the workability of maintenance. Also, for example, it is easy to replace an existing mesh ring that requires maintenance with a new mesh ring, which reduces the downtime of the resist coating apparatus 1 and improves the productivity of the wafer W to be subjected to resist coating.

[0049] Furthermore, if the mesh ring 150 is fixed to the cylindrical wall portion 145, the mesh ring 150 can be attached not only when manufacturing a new resist coating apparatus 1, but also to existing resist coating apparatuses that do not have a mesh ring 150. Therefore, the effects of suppressing clogging in the exhaust path and improving maintenance workability mentioned above can be obtained at a low cost.

[0050] Incidentally, in the method of fixing the mesh ring 150 described above, the solvent that falls onto the mesh ring 150 flows to the side wall 151, while at the location where the bracket portion 155 is formed, the solvent flows to the bracket portion 155, as shown in Figure 10. On the other hand, the fixing portion between the mesh ring 150 and the cylindrical wall portion 145 (the fastening portion with the attachment 180 by bolts 184) is located at a lower position than the upper end of the cylindrical wall portion 145 (i.e., the upper end of the attachment 180).

[0051] Therefore, the solvent that falls onto the mesh ring 150 and flows into the bracket portion 155 flows along the walls 156 and 157, and is drained by falling from the wall 157. In other words, if the fixing portion between the mesh ring 150 and the cylindrical wall portion 145 is located lower than the upper end of the cylindrical wall portion 145, it is possible to suppress the flow of solvent that flows from the mesh ring 150 towards the cylindrical wall portion 145 into the exhaust port 144 (Figure 7).

[0052] Furthermore, it is preferable that the mesh ring 150 is fixed so as not to contact the cup 110, except for the fixing portion with the cylindrical wall portion 145 (the fixing portion with the attachment 180 in the example of Figure 7). This suppresses the accumulation of resist liquid in the gap between the mesh ring 150 and the cup 110, and prevents the components from sticking together due to the solidification of the resist liquid.

[0053] In particular, if the mesh ring 150 and the bottom member 143 of the cup 110 (Figure 1) are not in contact, the resist solution diluted with the solvent or the dissolved solution of thread-like or cotton-like foreign matter dissolved with the solvent will be more easily drained.

[0054] Furthermore, although the above example describes a structure in which a cylindrical attachment 180 is fitted into the main body portion 145a of the cylindrical wall portion 145, the shape of the attachment 180 is not particularly limited as long as it can be detachably attached to the main body portion 145a. Also, the mounting position of the attachment 180 on the main body portion 145a is not limited to the upper end of the main body portion 145a, but may be, for example, the central or lower end of the main body portion 145a in the vertical direction. In other words, as long as the mesh ring 150 can be fixed to the main body portion 145a, the mounting positions of the main body portion 145a and the attachment 180 are not particularly limited.

[0055] Alternatively, the mesh ring 150 may be fixed to the main body portion 145a of the cylindrical wall portion 145 without providing the attachment 180 described above. On the other hand, it is preferable to provide the attachment 180 when, for example, it is difficult to directly fix the mesh ring 150 to the main body portion 145a, or when attaching a mesh ring 150 of the same specifications to a cup 110 for another model with a different exhaust port 144 shape.

[0056] For example, if multiple attachments 180 are prepared according to the shape of the exhaust port 144, the same mesh ring 150 can be applied to resist coating apparatuses 1 with different structures by appropriately switching the mesh ring 150 of the same specifications to each attachment 180. This may eliminate the need to manufacture a dedicated mesh ring 150 for each resist coating apparatus.

[0057] If the attachment 180 is not provided, it is preferable that the fixing portion (not shown) between the mesh ring 150 and the main body portion 145a of the cylindrical wall portion 145 is located lower than the upper end of the cylindrical wall portion 145 (i.e., the upper end of the main body portion 145a). This makes it easier for the solvent flowing 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, thereby suppressing the inflow of solvent into the exhaust port 144.

[0058] The general configuration of the resist coating apparatus 1 according to the embodiment has been described above. Next, other configuration examples of the cylindrical mesh ring 150 will be described.

[0059] (Liquid receiving section) Figure 11 is a cross-sectional view of the cup 110 for illustrating the liquid receiving section 153. Figure 12 is a diagram showing an example of the solvent flow supplied to the mesh ring 150, where the thick arrows schematically indicate the direction of solvent flow.

[0060] As shown in Figure 11, it is preferable that the cylindrical mesh ring 150 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 (towards the outer cup 120) from the outer peripheral surface of the side wall 151. Furthermore, the outer peripheral end of the liquid receiving portion 153 is located even further outward than the outer peripheral surface of the side wall 132 of the inner cup 130.

[0061] The side wall 151 and the liquid receiving portion 153 may be a single piece obtained by integral molding, or they may be composed of multiple parts assembled together. The liquid receiving portion 153 does not have to be horizontal in shape, but if the side wall 151 and the liquid receiving portion 153 are formed as a single part by processing a metal plate such as stainless steel, for example, it is preferable that it be horizontal in shape from the viewpoint of ease of processing.

[0062] As shown in Figure 12, when a liquid receiving section 153 is provided, the solvent flowing down along the outer surface of the inner cup 130 falls from the lower end of the side wall 132 into the liquid receiving section 153. Therefore, even solvent that would not reach the side wall 151 if the liquid receiving section 153 were not present can be received and collected by the liquid receiving section 153.

[0063] The solvent that falls into the liquid receiving section 153 flows toward the inner or outer circumferential end of the upper surface (liquid receiving surface 153a) of the liquid receiving section 153. Solvent heading toward the inner circumferential end of the liquid receiving surface 153a is supplied from the inner circumferential end to the inner circumferential surface of the side wall 151. On the other hand, solvent heading toward the outer circumferential end of the liquid receiving surface 153a flows from the outer circumferential end along the lower surface of the liquid receiving section 153 and is supplied to the outer circumferential surface of the side wall 151.

[0064] Thus, when the mesh ring 150 has a liquid receiving portion 153, more solvent flowing down along the outer surface of the inner cup 130 can be recovered and supplied to the mesh ring 150. As a result, the dilution of the resist liquid collected in the mesh ring 150 or the dissolution of solidified resist liquid is promoted, and the effect of suppressing clogging of the exhaust path with foreign matter can be enhanced.

[0065] The shape of the liquid receiving portion 153 is not limited to the L-shape shown in Figure 12, but may be T-shaped, for example. On the other hand, while exhaust is being performed in the cup 110, an exhaust flow is formed in the direction from the outer circumference to the inner circumference of the mesh ring 150 (from left to right in Figure 12). For this reason, if the liquid receiving portion 153 is T-shaped, the solvent flowing along the inner edge of the liquid receiving portion 153 may have difficulty reaching the side wall 151 due to the influence of the exhaust flow.

[0066] Therefore, as shown in Figure 12, when the outer peripheral end of the liquid receiving portion 153 protrudes outward from the side wall 132 of the inner cup 130, it is preferable that the inner peripheral end 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 end of the liquid receiving portion 153 to the side wall 151 compared to a T-shaped liquid receiving portion.

[0067] Furthermore, the shape of the liquid receiving portion 153 may be, for example, the shape shown in Figures 13(a) to (d).

[0068] Figure 13(a) shows an example in which the outer peripheral end of the liquid receiving section 153 and the outer peripheral surface of the side wall 151 are connected by an inclined surface 153b. In the liquid receiving section 153 shown in Figure 12, as indicated by the dotted arrow in Figure 12, some of the solvent may fall from the outer peripheral end of the liquid receiving section 153, and the solvent may not be supplied to the side wall 151. On the other hand, with the liquid receiving section 153 having an inclined surface 153b as shown in Figure 13(a), the solvent flowing down from the outer peripheral end of the liquid receiving surface 153a flows more easily along the inclined surface 153b, thus increasing the amount of solvent supplied to the side wall 151.

[0069] Figure 13(b) shows an example in which a side wall 154 is provided at the outer peripheral end of the liquid receiving section 153, extending upward from the liquid receiving section 153. The side wall 154 is a cylindrical wall, and the solvent flowing down along the outer peripheral surface of the inner cup 130 falls onto the liquid receiving surface 153a 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 towards the inner peripheral end of the liquid receiving surface 153a. In other words, with the liquid receiving section 153 shown in Figure 13(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.

[0070] Figure 13(c) shows an example where the outer circumferential edge of the liquid receiving surface 153a is higher than the inner circumferential edge, and the liquid receiving surface 153a slopes downward from the outer circumferential edge to the inner circumferential edge. According to the liquid receiving section 153 shown in Figure 13(c), solvent that falls onto the liquid receiving surface 153a flows down toward the inner circumferential edge of the liquid receiving surface 153a, while it is less likely to fall from the outer circumferential 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 circumferential surface of the side wall 151.

[0071] Figure 13(d) shows an example where the outer circumferential edge of the liquid receiving surface 153a is lower than the inner circumferential edge, and the liquid receiving surface 153a is inclined upward from the outer circumferential edge to the inner circumferential edge. According to the liquid receiving section 153 shown in Figure 13(d), solvent that falls onto the liquid receiving surface 153a flows down toward the outer circumferential edge of the liquid receiving surface 153a, while it is less likely to fall from the inner circumferential 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 circumferential surface of the side wall 151.

[0072] (Examples of opening shapes) Next, other examples of the shape of the opening 152 will be described. Figure 14 is a perspective view of the mesh ring 150.

[0073] The openings 152 shown in Figure 14 are rectangular in shape, with their shorter sides located at the upper and lower ends. The openings 152 extend from the upper end to the lower end of the side wall 151 of the mesh ring 150, and each opening 152 is spaced apart along the circumferential direction of the mesh ring 150.

[0074] When the opening 152 has this shape, it is possible to suppress the blockage of the opening 152 by the solvent supplied to the mesh ring 150, and to easily maintain the desired exhaust pressure during cup exhaust. The reason for this will be explained below with reference to Figure 15.

[0075] Figure 15 shows an example of the residual solvent state at the opening 152, where the black circles schematically represent the solvent remaining at the opening 152.

[0076] The solvent supplied to the mesh ring 150 may remain attached to the side wall 151 or opening 152 of the mesh ring 150 without being drained. In this case, as shown in Figure 15(a), if the shape of the upper end of the opening 152 is not horizontal, such as being elliptical or circular, a liquid film of solvent is likely to form on the opening 152 as the solvent flowing from above to below the side wall 151 passes through the opening 152.

[0077] Even if there are openings 152a that are blocked by the liquid film described above, there are also openings 152b that are open without a liquid film forming, so the resist coating process described above can be performed. However, if there are blocked openings 152a, the number of openings 152b through which the exhaust flow can pass is relatively reduced, making it difficult to maintain the desired exhaust pressure in the cup exhaust. For this reason, in order to perform the resist coating process while maintaining the exhaust capacity in 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.

[0078] In contrast, as shown in Figure 15(b), if the upper end shape of the opening 152 is horizontal, it becomes difficult for a liquid film that would block the opening 152 to form. For this reason, it is preferable that the upper end of the opening 152 be formed horizontally.

[0079] Furthermore, it is preferable that the opening 152 is rectangular in shape, as shown in Figure 15(b), with the shorter sides located at the upper and lower ends of the opening 152. This further suppresses the formation of a liquid film by the solvent supplied to the mesh ring 150.

[0080] On the other hand, if multiple rectangular openings 152 are arranged in the height direction of the mesh ring 150, as shown in Figure 15(b), solvent droplets may form in each of the openings 152 that are aligned in the height direction.

[0081] Therefore, it is preferable that the rectangular opening 152 extends from the upper end to the lower end of the side wall 151 of the mesh ring 150, as shown in Figures 14 and 15(c) above. This reduces the number of openings 152 aligned in the height direction, and thus reduces the number of locations where solvent droplets are likely to form. As a result, even if solvent droplets form in the opening 152, the reduction in the overall opening area of ​​the mesh ring 150 can be suppressed. Therefore, it is possible to maintain the desired exhaust pressure even if the maintenance frequency of the mesh ring 150 is reduced.

[0082] (Annular mesh ring) In the above example, a cylindrical mesh ring 150 was described, but the mesh ring 150 may also be an annular shape, such as a circular ring.

[0083] Figure 16 shows a longitudinal section of a cup illustrating an annular mesh ring. Figure 17 shows a cross-sectional view of a cup illustrating an annular mesh ring. Figure 18 shows an example of solvent flow supplied to an annular mesh ring, with the thick arrows in the figure schematically indicating the direction of solvent flow.

[0084] The annular mesh ring 190 shown in Figure 16 is positioned below the side wall 132 of the inner cup 130, spaced apart from the lower end of the side wall 132. As shown in Figure 17, the mesh ring 190 is fixed to the cylindrical wall portion 145 via an attachment 180. The openings 191 through which the exhaust flow passes are formed to penetrate from the upper surface to the lower surface of the mesh ring 190, and multiple openings 191 are provided at intervals along the circumferential direction of the mesh ring 190. Furthermore, the outer peripheral end of the mesh ring 190 protrudes outward (towards the outer cup 120) from the outer peripheral surface of the side wall 132 of the inner cup 130.

[0085] Even with such annular mesh ring 190, the resist liquid that flows down along the outer surface of the inner cup 130 during the resist coating process, or the resist liquid that has solidified into a thread-like form, can be collected. As shown in Figure 18, the solvent that flows down along the outer surface of the inner cup 130 is supplied to the mesh ring 190, thereby diluting the resist liquid collected in the mesh ring 190 or dissolving the resist liquid that has solidified into a thread-like form.

[0086] Furthermore, as shown in Figure 19, if the fixing portion (fastening portion by bolt 184) between the mesh ring 190 and the attachment 180 is located lower than the upper end of the cylindrical wall portion 145 (upper end of the attachment 180), it is possible to suppress the flow of solvent from the mesh ring 190 towards the cylindrical wall portion 145 into the exhaust port 144 (Figure 17).

[0087] Furthermore, as shown in Figure 20, the annular mesh ring 190 may be provided with a side wall 192 that acts as a cylindrical wall extending upward from the outer peripheral end of the forming surface of the opening 191. This makes it easier for the solvent flowing down from the inner cup 130 to flow towards the inner peripheral end of the forming surface of the opening 191, thereby promoting the dilution of the resist liquid remaining closer to the exhaust side and the dissolution of solidified resist liquid.

[0088] In the above description, mesh rings 150 and 190 were used as examples of coating liquid collection sections, but the coating liquid collection section is not particularly limited as long as it has a structure that can collect resist liquid. For example, the coating liquid collection section may be an annular plate 195 as shown in Figures 21 and 22, which does not have the opening 191 of the annular mesh ring 190 shown in Figures 16 to 20.

[0089] The annular plate 195 is formed from a metal plate, such as stainless steel. The horizontal portion 196 of this annular plate 195 receives and collects the resist liquid falling from the inner cup 130. Even with such an annular plate 195, the solvent flowing down from the inner cup 130 can dilute the resist liquid collected by the annular plate 195 and dissolve the solidified resist, thereby suppressing clogging of the exhaust path with foreign matter.

[0090] Furthermore, as shown in Figure 22, the annular plate 195 may be provided with side walls 197 as cylindrical walls extending upward from the outer peripheral end of the horizontal portion 196.

[0091] The liquid processing apparatus described above has been explained using resist coating apparatus 1 as an example. The liquid processing apparatus described above can also be applied to processing substrates other than semiconductor wafers, such as FPD (flat panel display) substrates and mask reticles for photomasks.

[0092] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope of the appended claims, the technical examples of the disclosure, or the spirit thereof. For example, the constituent elements of the embodiments described above can be combined in any way. Such any combination will naturally yield the effects and benefits of each constituent element in the combination, as well as other effects and benefits that will be apparent to those skilled in the art from the description herein.

[0093] Furthermore, the effects described herein are merely descriptive or illustrative and not limiting. In other words, the technology relating to this disclosure may produce other effects that are obvious to those skilled in the art from the description herein, in addition to or instead of the effects described herein.

[0094] Furthermore, the following configuration examples also fall within the technical scope of this disclosure. (1) A liquid processing apparatus for applying a coating solution onto a substrate, A substrate holding unit that holds and rotates the substrate, A coating liquid supply unit that applies the coating liquid to the substrate held in the substrate holding unit, The substrate holder portion comprises a cup surrounding the substrate, The aforementioned cup is An outer cup portion arranged on the outside of the substrate holding portion, An inner cup portion is located on the inner circumference side of the outer cup portion and below the substrate holding portion, and has a wall that extends downward, An exhaust path is provided between the outer cup portion and the inner cup portion, A cylindrical wall portion is provided below the inner cup portion and has an upward-opening exhaust port that communicates with the exhaust path, The inner cup portion has a coating liquid collection section positioned below the wall body, with a gap between it and the lower end of the wall body, The coating liquid collection unit is equipped with a solvent supply unit that supplies the solvent for the coating liquid, The liquid collection unit is fixed to the cylindrical wall portion of the liquid processing apparatus. (2) The liquid processing apparatus according to (1), wherein the fixing portion between the coating liquid collection portion and the cylindrical wall portion is located below the upper end of the cylindrical wall portion. (3) The cylindrical wall portion is A cylindrical body, It has a mounting member that is detachably attached to the main body, The coating liquid collection unit is attached to the mounting member, The liquid processing apparatus according to (1) or (2), wherein the fixing portion is the fixing portion between the coating liquid collection portion and the mounting member. (4) The mounting member is made of resin, as described in any of (1) to (3). (5) The liquid collection portion is non-contact with the cup, except for the portion fixed to the cylindrical wall portion, as described in any of (1) to (4). (6) The liquid collection section is cylindrical or annular and has a plurality of openings through which the exhaust flow passes, according to any one of (1) to (5). [Explanation of symbols]

[0095] 1. Resist coating apparatus 101 Spin Chuck 110 cups 120 Outer Cup 130 Inner Cup 132 Side wall 144 Exhaust vent 145 Cylindrical wall section 150 tubular mesh rings 152 Opening 163 Resist liquid supply nozzle 167 Solvent supply nozzle 170 Back rinse fluid supply nozzle 190 Annular Mesh Ring 195 Ring Plate d Exhaust path W wafer

Claims

1. A liquid processing apparatus for applying a coating solution onto a substrate, 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, The substrate holder portion comprises a cup surrounding the substrate, The aforementioned cup is An outer cup portion arranged on the outside of the substrate holding portion, An inner cup portion is located on the inner circumference side of the outer cup portion and below the substrate holding portion, and has a wall that extends downward, An exhaust path is provided between the outer cup portion and the inner cup portion, A cylindrical wall portion is provided below the inner cup portion and has an upward-opening exhaust port that communicates with the exhaust path, The inner cup portion has a coating liquid collection section positioned below the wall body, with a gap between it and the lower end of the wall body, The coating liquid collection unit is equipped with a solvent supply unit that supplies the solvent for the coating liquid, The coating liquid collection unit is fixed to the cylindrical wall portion, The fixing portion between the coating liquid collection portion and the cylindrical wall portion is located below the upper end of the cylindrical wall portion. The cylindrical wall portion is, A cylindrical body, It has a mounting member that is detachably attached to the main body, The coating liquid collection unit is attached to the mounting member, The aforementioned fixing part is a fixing part between the coating liquid collection part and the mounting member, in a liquid processing apparatus.

2. The liquid processing apparatus according to claim 1, wherein the mounting member is made of resin.

3. The liquid collection portion is non-contact with the cup, except for the portion fixed to the cylindrical wall portion, as described in claim 1 or 2.

4. The liquid processing apparatus according to claim 1 or 2, wherein the coating liquid collection section is cylindrical or annular and has a plurality of openings through which the exhaust flow passes.

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