Substrate processing apparatus and substrate processing method

Abstract

When supplying a processing solution to the substrate and performing the processing, the generation of mist and splash of the processing solution is suppressed. [Solution] The substrate processing apparatus of the present disclosure comprises: a coating liquid supply unit for supplying a coating liquid; at least one of a removal liquid supply unit for supplying a removal liquid to remove the coating film from the peripheral edge of a substrate on which a coating film is formed and which is rotating; and a cleaning liquid supply unit for supplying a cleaning liquid for cleaning the back surface of the substrate; an exhaust volume adjustment unit for adjusting the exhaust volume in a cup; a control unit that performs a first step of exhausting the contents of the cup at a first exhaust volume when supplying a coating liquid to the substrate; a second step of exhausting the contents of the cup at a second exhaust volume after supplying a coating liquid to the substrate and before supplying a removal liquid or cleaning liquid to the substrate; and a third step of exhausting the contents of the cup at a third exhaust volume when supplying a removal liquid or cleaning liquid to the substrate, and outputs a control signal such that the second exhaust volume is smaller than the first and third exhaust volumes.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a substrate processing method.

Background Art

[0002] In the manufacturing process of semiconductor devices, a coating film such as a resist film is formed on a substrate such as a semiconductor wafer (hereinafter referred to as a wafer). Patent Document 1 shows an example of a substrate processing apparatus for forming this resist film. In this substrate processing apparatus, when forming a coating film on a wafer stored in a cup, the exhaust amount in the cup is made relatively high in order to prevent the scattering of the atomized coating liquid from the wafer during the supply of the coating liquid. And after the supply of the coating liquid is completed and until the wafer is carried out from the cup, the exhaust amount in the cup is made relatively low.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique capable of suppressing the generation of mist and splash of a processing liquid when supplying the processing liquid to a substrate for processing.

Means for Solving the Problems

[0005] The substrate processing apparatus of the present disclosure includes a cup for storing a substrate, a rotary holding unit that holds and rotates the substrate in the cup, a coating liquid supply unit that supplies a coating liquid to form a coating film on the surface of the substrate, The substrate on which the coating film is formed and which rotates is provided with at least one of the following: a removal liquid supply unit that supplies a removal liquid to remove the coating film from the peripheral edge of the substrate, and a cleaning liquid supply unit that supplies a cleaning liquid to clean the back surface of the substrate. A displacement adjustment unit for adjusting the amount of exhaust in the cup, A control unit that outputs a control signal such that the second exhaust volume is smaller than the first and third exhaust volumes, and the following steps are performed: a first step of exhausting the contents of the cup with a first exhaust volume when the coating liquid is supplied to the substrate; a second step of exhausting the contents of the cup with a second exhaust volume after the coating liquid is supplied to the substrate and before the removal liquid or cleaning liquid is supplied to the substrate; and a third step of exhausting the contents of the cup with a third exhaust volume when the removal liquid or cleaning liquid is supplied to the substrate. It is equipped with. [Effects of the Invention]

[0006] This disclosure makes it possible to suppress the generation of mist and splash of the processing liquid when supplying the processing liquid to the substrate and performing the processing. [Brief explanation of the drawing]

[0007] [Figure 1] This is a longitudinal cross-sectional side view of a substrate processing apparatus according to the first embodiment. [Figure 2] This is a plan view of the aforementioned substrate processing apparatus. [Figure 3] This is a chart illustrating the processing of a reference example of the aforementioned substrate processing apparatus. [Figure 4] This is a longitudinal cross-sectional side view showing the substrate processing apparatus in the process of processing a wafer. [Figure 5] This is a longitudinal cross-sectional side view showing the substrate processing apparatus in the process of processing a wafer. [Figure 6] This is a longitudinal cross-sectional side view showing the substrate processing apparatus in the process of processing a wafer. [Figure 7] This graph shows the wafer film thickness distribution obtained through experiments. [Figure 8] This graph shows the wafer film thickness distribution obtained through experiments. [Figure 9] It is a flowchart showing the process of the first embodiment. [Figure 10] It is a flowchart showing the process of the second embodiment. [Figure 11] It is a longitudinal sectional view of the substrate processing apparatus during the process of the second embodiment. [Figure 12] It is a longitudinal sectional view of the substrate processing apparatus provided with the cup of the modification. [Figure 13] It is a plan view of the substrate processing apparatus provided with the cup of the modification. [Figure 14] It is a longitudinal sectional view showing the substrate processing apparatus during wafer processing. [Figure 15] It is a plan view of the substrate processing apparatus provided with the sub-processing unit of the modification. [Figure 16] It is a longitudinal sectional view of the substrate processing apparatus provided with the sub-processing unit of the modification. [Figure 17] It is a plan view of the substrate processing apparatus provided with the sub-processing unit of the modification. [Figure 18] It is a longitudinal sectional view of the substrate processing apparatus provided with the sub-processing unit of the modification.

Embodiments for Carrying Out the Invention

[0008] 〔First Embodiment〕 The substrate processing apparatus 1 according to the first embodiment will be described with reference to the longitudinal sectional view of FIG. 1 and the plan view of FIG. 2. The substrate processing apparatus 1 supplies resist as a coating liquid to the central portion of a wafer W which is a circular substrate. By spin coating, the resist is applied to the entire surface of the wafer W to form a resist film. In addition, in the substrate processing apparatus 1, before forming the resist film, a process (pre-wet) of supplying a solvent of the resist to the surface of the wafer W to enhance the wettability of the resist with respect to the surface of the wafer W is also performed.

[0009] In the substrate processing apparatus 1, after exposing the resist film to the airflow by rotating the wafer W for drying and solidification, an EBR (Edge Bead Removal) process and a backside cleaning process are performed on the wafer W. The EBR process is a process of dissolving the resist film by supplying a resist solvent to the peripheral portion of the surface of the rotating wafer W and removing it from the peripheral portion. The backside cleaning process is a process of cleaning by supplying a resist solvent as a cleaning liquid to the backside (lower surface) of the rotating wafer W. The EBR process and the backside cleaning process are performed in parallel. The resist, the solvent for pre-wetting, the solvent (cleaning liquid) for the backside cleaning process, and the solvent (removing liquid) for the EBR process described above are processing liquids for processing the wafer W, and among them, the resist is a coating liquid that forms a resist film, which is a coating film, by being applied to the wafer W.

[0010] The substrate processing apparatus 1 includes a spin chuck 21, a rotation mechanism 23, a cup 3, exhaust pipes 44 and 45, a main processing unit 5, and a sub-processing unit 6. The main processing unit 5 supplies a resist and a solvent for pre-wetting, and the sub-processing unit 6 supplies a solvent for the EBR process. The spin chuck 21, which is a rotation holding unit, adsorbs the central portion of the backside of the wafer W and holds the wafer W horizontally, and is connected to the rotation mechanism 23 via a shaft 22 extending in the vertical direction. By the rotation mechanism 23, the spin chuck 21 rotates together with the held wafer W around the vertical axis. Although not shown, the substrate processing apparatus 1 includes a lifting member that can move up and down in order to transfer the wafer W between the transfer mechanism that transfers the wafer W to the substrate processing apparatus 1 and the spin chuck 21.

[0011] The spin chuck 21 is provided in a circular cup 3 in a plan view, and the wafer W is held by the spin chuck 21 by being housed in the cup 3. The cup 3 receives various processing liquids that scatter or fall from the wafer W and removes them from a drain port 43 provided at the bottom. In order to prevent the scattering of the processing liquid to the outside of the cup 3, the inside of the cup 3 is exhausted.

[0012] Cup 3 includes an outer cup 31. The outer cup 31 constitutes the outer wall of cup 3 and surrounds the sides of the wafer W and spin chuck 21. The outer cup 31 has an upright cylindrical side wall 32 and an annular upper wall portion 33 extending from the upper part of the side wall 32. More specifically, the tip of the upper wall portion 33 extends diagonally upward toward the center of cup 3. The tip of the upper wall portion 33 protrudes vertically upward and vertically downward, respectively, forming an annular upper projection 34A and a lower projection 34B in a plan view. These upper projection 34A and lower projection 34B prevent the scattering of liquid (including mist) to the outside of cup 3. The lower projection 34B prevents the backflow of airflow below the upper wall portion 33, thereby preventing the scattering of mist. The circular space surrounded by the tip of the upper wall portion 33, on which the upper projection 34A and the lower projection 34B are formed, is the opening 34C of the cup 3.

[0013] Cup 3 is surrounded by an outer cup 31 and includes an inner member 35 that surrounds the shaft 22. The central side of the inner member 35 is formed, for example, in the shape of a horizontal plate, and forms a central region 35A where back surface cleaning nozzles 41 for cleaning the back surface of the wafer W are arranged. Multiple back surface cleaning nozzles 41 are provided, for example, spaced apart in the circumferential direction of cup 3. In the illustrated example, two back surface cleaning nozzles 41 are shown. Each back surface cleaning nozzle 41 is connected to a cleaning liquid supply mechanism 42, which includes, for example, a valve, a pump, and a storage section for storing the cleaning liquid, which is the solvent described above. The cleaning liquid supply mechanism 42 can pump the cleaning liquid from the storage section to each back surface cleaning nozzle 41. The back surface cleaning nozzles 41 discharge the cleaning liquid diagonally upward from the center side of cup 3 toward the periphery side, supplying it to the back surface of the wafer W to perform back surface cleaning. The back surface cleaning nozzles 41 and the cleaning liquid supply mechanism 42 constitute the cleaning liquid supply section.

[0014] The peripheral edge of the inner member 35 forms a sloping region 35B that slopes downward towards the peripheral edge of the cup 3, guiding the liquid that falls from the wafer W towards the bottom of the cup 3. The inner member 35 is also provided with a cylindrical downward wall 36 that rises vertically downward from the outer peripheral edge of the sloping region 35B, and a gap is formed between the downward wall 36 and the side wall 32 of the outer cup 31, which serves as a discharge passage for the processing liquid and gas.

[0015] Furthermore, cup 3 has an annular bottom wall 37 whose outer periphery is connected to the lower end of the outer cup 31 and which is positioned to surround the rotating mechanism 23, and this bottom wall 37 forms the bottom of cup 3. The inner periphery of the bottom wall 37 extends upward to form a vertical wall, and the upper end of this vertical wall extends horizontally so as to extend toward the periphery side of cup 3 and connects to the upper end of the descending wall 36 and the upper end of the inclined region 35B to form a horizontal wall. These vertical and horizontal walls are shown as partition walls 38.

[0016] A drain port 43 is provided in the bottom wall 37 described above. In addition, multiple, for example, two, upright exhaust pipes 44 are provided in the bottom wall 37, and the upper end of each exhaust pipe 44 is positioned above the lower end of the descending wall 36, thereby preventing liquid from flowing into the exhaust pipe 44. In other words, the gas and liquid in the cup 3 are separated, with the liquid flowing into the drain port 43 and the gas flowing into the exhaust pipe 44. The downstream ends of the two exhaust pipes 44 merge to form a single exhaust pipe 45.

[0017] A pressure detection unit 46 is provided in the exhaust pipe 45. A damper 47 is interposed in the exhaust pipe 45 downstream of the location where the pressure detection unit 46 is provided. The downstream end of the exhaust pipe 45 is connected to an exhaust source (not shown). This exhaust source constantly exhausts the inside of the cup 3 through the exhaust pipes 44 and 45, and the surrounding gas, such as air, flows into the cup 3 through the opening 34C of the cup 3. This exhaust source is, for example, the exhaust passage of a factory where the substrate processing device 1 is installed, and is under negative pressure relative to atmospheric pressure.

[0018] The pressure detection unit 46 transmits a detection signal corresponding to the pressure in the exhaust pipe 45 upstream of the damper 47 to the control unit 100, which will be described later. Based on this detection signal, the control unit 100 can detect the pressure in the exhaust pipe 45 upstream of the damper 47. The pressure detected by the pressure detection unit 46 in this way will be referred to as the exhaust pressure in the following description. The damper 47, which is the exhaust volume adjustment unit, operates according to the control signal output from the control unit 100, and the opening degree of the damper 47 is adjusted so that the exhaust pressure becomes a set value.

[0019] As described above, the substrate processing apparatus 1 is formed by exhaust pipes 44 and 45 and a damper 47 and has an exhaust passage connected to the cup 3, and the opening degree of this exhaust passage is adjusted by the damper 47. The exhaust pressure detected based on the detection signal of the pressure detection unit 46 described above, the amount of exhaust per unit time flowing from the cup 3 to the exhaust pipes 44 and 45 and the opening degree of the damper 47 correspond to each other, and the larger the opening degree of the damper 47, the larger the amount of exhaust per unit time flowing from the cup 3 to the exhaust pipes 44 and 45 and the larger the exhaust pressure.

[0020] Returning to the explanation of the inside of cup 3, above the inner member 35 inside cup 3, there is an annular plate-shaped intermediate member 48 that extends diagonally upward from the peripheral side of cup 3 toward the center side of cup 3. The tip of the intermediate member 48 is close to the wafer W, and the upper surface of the intermediate member 48 is configured as an inclined surface 48A that slopes downward toward the peripheral side. The base end of the intermediate member 48 is supported by a plurality of support members 49 that are spaced apart from each other in the circumferential direction of cup 3. The airflow between the intermediate member 48 and the upper wall portion 33 of the outer cup 31 flows through a channel formed between the support members 49 into the gap between the side wall 32 and the descending wall 36 of the outer cup 31, and heads toward the bottom wall 37 of cup 3.

[0021] The outer cup 31, intermediate member 48, and inner member 35 are arranged coaxially, meaning their central axes are aligned in a plan view. The opening 34C of the cup 3 formed by the upper wall portion 32 of the outer cup 31 is formed to be relatively large, so that the edge of the opening 34C is located above the inclined region 35B of the intermediate member 48 and inner member 35. If the opening 34C were relatively small, and the intermediate member 48 and the upper wall portion 33 were in close proximity to the periphery of the wafer W, the airflow velocity at that location would be relatively high during the drying period for drying the resist R described later, which could lead to a large difference in the thickness of the resist film between the central and peripheral parts of the wafer W. To prevent this problem, the opening 34C is formed to be relatively large as described above.

[0022] Let us describe in more detail an example of how the opening 34C is formed. Let M be the horizontal center position of the inclined surface 48A of the intermediate member 48. That is, the center position M is a virtual circle that divides the inclined surface 48A into an inner ring and an outer ring having the same width M1 in a plan view. For example, the tip position of the upper wall portion 33 (i.e., the position of the inner periphery of the annular upper projection 34A and lower projection 34B) is located on the periphery side of the cup 3 than the center position M. In other words, in a plan view, the center position M overlaps with and is exposed by the opening 34C of the cup 3. As described above, because the opening 34C is relatively large, it is effective to provide liquid receiving portions 71 and 72 for preventing liquid splashing, as will be described in detail later as a modification of the device.

[0023] Next, the main processing unit 5 will be described. The main processing unit 5 includes a resist supply nozzle 51, a solvent supply nozzle 52, a resist supply mechanism 53, a solvent supply mechanism 54, an arm 55, a moving mechanism 56, a guide 57, and a standby unit 58. There are, for example, multiple resist supply nozzles 51, each discharging resist pumped from the resist supply mechanism 53 vertically downwards. The solvent supply nozzle 52 discharges resist pumped from the solvent supply mechanism 54 vertically downwards. The resist supply mechanism 53 includes a pump, a valve, a resist storage unit, etc., and can pump the resist from the resist storage unit to the resist supply nozzle 51. The solvent supply mechanism 54 includes a pump, a valve, a solvent storage unit, etc., and can pump the solvent from the solvent storage unit to the solvent supply nozzle 52.

[0024] Multiple resist supply mechanisms 53 are provided, and each resist supply mechanism 53 supplies resist to a different resist supply nozzle 51. The type of resist supplied from each resist supply mechanism 53 is different. Therefore, different types of resist are dispensed from each resist supply nozzle 51. For wafer W processing, resist is supplied from one of the multiple resist supply nozzles 51 and the processing is carried out. In the illustrated example, two sets of resist supply nozzles 51 and resist supply mechanisms 53 are shown, but the number of such sets may be more than two. The resist supply nozzles 51 and resist supply mechanisms 53 correspond to the coating liquid supply section.

[0025] A resist supply nozzle 51 and a solvent supply nozzle 52 are supported at the tip of the arm 55. The base end of the arm 55 is connected to a moving mechanism 56. The moving mechanism 56 can move horizontally along a guide 57 and can also raise and lower the arm 55. A box-shaped waiting section 58 that opens upward is provided on the outside of the cup 3. The moving mechanism 56 allows the resist supply nozzle 51 and solvent supply nozzle 52 to move between the opening of the waiting section 58 and the inside of the cup 3, supplying solvent and resist, respectively, onto the center of the wafer W.

[0026] Next, the sub-processing unit 6 will be described. The sub-processing unit 6 includes a removal liquid supply nozzle 61 that supplies the resist solvent as a removal liquid, a removal liquid supply mechanism 64, an arm 65, a moving mechanism 66, a guide 67, and a standby unit 68. The removal liquid supply nozzle 61 discharges the solvent, which is pumped from the removal liquid supply mechanism 64, downwards. The removal liquid supply mechanism 64 includes a pump, a valve, a removal liquid storage unit, etc., and can pump the removal liquid (solvent) in the storage unit to the removal liquid supply nozzle 61. The removal liquid supply nozzle 61 and the removal liquid supply mechanism 64 constitute the removal liquid supply unit.

[0027] A removal liquid supply nozzle 61 is supported at the tip of the arm 65. The base end of the arm 65 is connected to a moving mechanism 66. The moving mechanism 66 can move horizontally along a guide 67 and can also raise and lower the arm 65. A box-shaped waiting section 68 opening upward is provided on the outside of the cup 3. The moving mechanism 66 allows the removal liquid supply nozzle 61 to move between the opening of the waiting section 68 and the inside of the cup 3, supplying the removal liquid onto the periphery of the wafer W.

[0028] The removal liquid supply nozzle 61 discharges the removal liquid in a direction inclined with respect to the vertical when viewed from the side, and when viewed from above, the removal liquid is discharged from the center of the wafer W toward the periphery. The rotation direction of the wafer W is clockwise when viewed from above, and the discharge direction of the removal liquid follows this rotation direction of the wafer W. In other words, the discharge direction of the removal liquid is set relative to the rotation direction of the wafer W so that the solvent discharged and landed on the wafer W immediately moves away from the removal liquid supply nozzle 61 due to the rotation of the wafer W.

[0029] Next, the control unit 100 shown in Figure 1 will be described. The control unit 100 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program that controls the processing of wafers W in the substrate processing apparatus 1. The program storage unit also stores a program that controls the operation of various moving mechanisms and drive mechanisms, the supply and disconnection of processing liquid from various processing liquid supply mechanisms, and the opening degree of the damper 47 to realize the processing of wafers W in the substrate processing apparatus 1. The program is composed of a group of steps necessary to carry out the transport and processing of wafers W in the substrate processing apparatus 1, and the control unit 100 outputs control signals to each part of the substrate processing apparatus 1 according to the program, and the transport and processing are carried out by controlling each part as described above.

[0030] The above program may be recorded on a computer-readable storage medium H and installed from said storage medium H to the control unit 100. The storage medium H may include ROM, RAM, or a hard disk, but its structure and type are not limited, and it may be temporary or permanent. The control unit 100 may include a part that stores, reads, and executes the program for realizing board processing and performs related communications, and the location of each part may be either inside or outside the board processing device 1. The control unit 100 may be one or more circuits, and may be provided as a single unit or in separate parts.

[0031] Before describing the processing of the embodiment performed in this substrate processing apparatus 1, a reference example of processing that can be performed in the substrate processing apparatus 1 will be described with reference to the timing chart in Figure 3. This timing chart shows the change in rotational speed and the change in exhaust pressure during a series of processing steps of the wafer W. As described above, the exhaust pressure and the amount of exhaust in the cup 3 change in accordance with the change in the opening degree of the damper 47 provided in the exhaust pipe 45. Therefore, the chart showing the change in exhaust pressure in Figure 3 is also a chart showing the change in the amount of exhaust in the cup 3 and the opening degree of the damper 47. Also, Figures 4 to 6, which are longitudinal cross-sectional side views of the substrate processing apparatus 1 showing the state of the wafer W during processing, will be referred to as appropriate. The solid or dotted arrows in Figures 4 to 6 indicate the airflow supplied into the cup 3, and the airflow velocity is smaller and the exhaust pressure is lower when indicated by a dotted arrow than when indicated by a solid arrow.

[0032] With the exhaust pressure set to a relatively high A1, a predetermined amount of solvent is supplied from the solvent supply nozzle 52 to the center of the surface of the wafer W held in the spin chuck 21, and the wafer W rotates at a rotation speed B1 (time t1). Pre-wetting is performed as the solvent spreads toward the periphery of the wafer W. Subsequently, after the rotation speed of the wafer W decreases and, for example, the rotation stops temporarily (time t2), a predetermined amount of resist is supplied from the resist supply nozzle 51 to the center of the surface of the wafer W, and the rotation speed of the wafer W increases to B2, which is higher than B1 (time t3). The resist R is spread toward the periphery of the wafer W, and spin coating is performed. That is, as shown in Figure 4, the entire surface of the wafer W is covered with resist R.

[0033] The discharge of resist R from the resist supply nozzle 51 stops, and after the entire surface of the wafer W is covered with the resist R, the rotation speed of the wafer W decreases to B3 (time t4), and the in-plane distribution of resist R on the wafer W is adjusted. Subsequently, the opening of the damper 47 decreases, causing the exhaust pressure to decrease (i.e., the amount of exhaust from cup 3 decreases) to A2, and the rotation speed of the wafer W increases to B4 (time t5). The resist R is exposed to the airflow, and the volatilization of the solvent contained in the resist R progresses. That is, as the drying of the resist R progresses, the resist R solidifies. As a result, the resist film R1 is formed as shown in Figure 5.

[0034] Next, as the opening of the damper 47 increases, the exhaust pressure rises (i.e., the amount of exhaust from cup 3 increases), and as it returns to, for example, A1, the rotation speed of the wafer W increases to B5, and the removal liquid L1 is discharged from the removal liquid supply nozzle 61 to the peripheral edge of the surface of the wafer W, and EBR is performed (time t6). Also, the cleaning liquid L2 is discharged from the back surface cleaning nozzle 41 to the back surface of the wafer W, and the back surface is cleaned. The resist film R1 on the peripheral edge of the wafer W is removed, and the entire back surface peripheral edge of the wafer W is cleaned. Then, for example, after the supply of cleaning liquid L2 to the wafer W is stopped, the supply of removal liquid L1 to the wafer W is stopped, the rotation speed of the wafer W decreases, and as if it were B1 again (time t7). After the wafer W is dried by the complete dispersal of the removal liquid L1 and cleaning liquid L2 due to rotation, the rotation of the wafer W stops, and the processing of the wafer W is completed (time t8).

[0035] In the above example processing, the values ​​of exhaust pressures A1 and A2 are assumed to remain constant between wafers W. That is, when processing the wafer W that is transported to the apparatus first and the subsequent wafer W, the damper 47 changes its opening in the same way from time t1 to t8, and processing is carried out. Exhaust pressure A1 is, for example, 60 Pa, and exhaust pressure A2 is, for example, 20 Pa. In the following explanation, the period from time t5 to t6, when the resist R is dried and the resist film R1 is formed, will be referred to as the drying period, with the exhaust pressure being A2. As described above, the processing of wafer W proceeds, so this drying period is a period during which no processing liquid is supplied to wafer W.

[0036] The step of setting the exhaust pressure to A1 using the damper 47 during time t1 to time t5 (i.e., the period including the supply of the coating solution to the substrate) corresponds to the first step. The step of setting the exhaust pressure to A2 using the damper 47 during the drying period from time t5 to time t6 (i.e., the period after the supply of the coating solution to the substrate and before the supply of the cleaning solution and removal solution) corresponds to the second step. The step of setting the exhaust pressure to A1 using the damper 47 during time t6 to time t7 (i.e., the period during which the cleaning solution and removal solution are supplied to the substrate), which is before the drying of the wafer W from time t7 to t8, corresponds to the third step. As previously mentioned, since exhaust pressure A1 > A2, if we consider the exhaust volumes in cup 3 in the first, second, and third steps as the first exhaust volume C1, second exhaust volume C2, and third exhaust volume C3, respectively, then the operation of damper 47 is controlled by a control signal from control unit 100 so that first exhaust volume C1 = third exhaust volume C3 > second exhaust volume C2.

[0037] During the periods t1 to t5 and t6 to t7, when the wafer W rotation speed is set to a relatively high value in order to discharge the processing liquid and spread it on the wafer W for processing, a relatively large amount of mist will be generated in cup 3. To prevent contamination of other wafers W and equipment by the outflow of this mist from cup 3, the exhaust pressure is set to a relatively high A1 during these periods so that the mist is removed by the exhaust flow formed in cup 3.

[0038] Incidentally, with respect to the resist film R1, the film thickness at the periphery of the wafer W changes relative to the film thickness at the center of the wafer W, depending on the exhaust pressure A2 during the drying period. Figure 7 is a graph showing the results of Experiment 1, which provides the basis for this. In Experiment 1, after performing the reference example treatment on each of several wafers W under the same conditions except for different exhaust pressure A2 settings, the film thickness of the resist film R1 formed on each wafer W was measured at various points in the plane of the wafer W.

[0039] The vertical axis of the graph shows the thickness of the resist film R1, and is marked at regular intervals. The horizontal axis of the graph shows each position along the diameter of the wafer W as the distance from the center of the wafer W. This horizontal axis is also marked at regular intervals, with the 2γ and -2γ markings indicating the edges of the wafer W, respectively. As shown in this graph, the larger the exhaust pressure A2 during the drying period (i.e., the larger the exhaust volume per unit time from cup 3), the larger the thickness of the resist film R1 at the periphery of the wafer W. Furthermore, depending on the setting of the exhaust pressure A2, the thickness of the film at the periphery of the wafer W may be smaller or larger than the thickness at the center. From these experimental results, it can be seen that the smaller the exhaust pressure A2, the greater the effect of reducing the thickness of the resist film R1 at the periphery of the wafer W.

[0040] As described above, if the exhaust pressure A2 during the drying period becomes too high, the thickness of the wafer W at its periphery will increase, reducing the uniformity of the film thickness within the wafer W. Therefore, in order to prevent mist scattering from cup 3 while also preventing the problem of reduced film thickness uniformity, the exhaust pressure A2 during the drying period is set to a lower value than the exhaust pressure A1 during the period from time t1 to time t5 and the exhaust pressure A1 during the period from time t6 to t7. The relationship of the exhaust volume in cup 3 is as follows, as described above: 1st exhaust volume C1 = 3rd exhaust volume C3 > 2nd exhaust volume C2.

[0041] By the way, the findings based on other experiments are explained below. The thickness of the resist film R1 after processing changes depending on the rotation speed B4 of the wafer W during the drying period. Figure 8 is a graph showing the results of Experiment 2, which is the basis for this finding. In the graph of Figure 8, similar to the graph of Figure 7, the horizontal axis is set to the distance from the center of the wafer W and the vertical axis is set to the thickness of the resist film R1. In Experiment 2, the reference example processing was performed on each of several wafers W under the same conditions except for a different setting of rotation speed B4, and then the thickness of the resist film R1 formed on each wafer W was measured at various points in the plane of the wafer W.

[0042] As shown in the graph in Figure 8, the higher the rotation speed B4 during the drying period, the smaller the thickness of the resist film R1 across the entire surface of the wafer W. Figure 8 also shows that the difference between the film thickness at the center of the wafer W and the film thickness at the periphery of the wafer W changes depending on the rotation speed B4. More specifically, the lower the rotation speed B4, the larger the film thickness at the periphery of the wafer W is relative to the film thickness at the center of the wafer W.

[0043] Further experiments and their verification will be described. During the drying period, no processing solution is supplied to the wafer W. Therefore, compared to the period before the drying period (times t1-t5) and the period after the drying period (times t6-t7), when the processing solution is supplied, the scattering of mist outside cup 3 is suppressed. However, even during this drying period, the higher the rotation speed B4 of the wafer W, or the lower the exhaust pressure, the higher the risk of mist scattering outside cup 3. Table 1 below shows the results of Experiment 3, which provides the basis for this conclusion.

[0044] In Experiment 3, the combination of rotation speed B4 and exhaust pressure A2 was changed for each wafer W, and the reference example processing was performed on multiple wafers W. The number of mist particles detected during the drying period was measured by a detector placed outside cup 3. In Table 1, combinations of rotation speed B4 and exhaust pressure A2 values ​​in which mist was detected are indicated as NG. As shown in Table 1, Experiment 3 shows that to prevent mist from scattering outside cup 3, the exhaust pressure A2 should be set to 20 Pa or higher when the rotation speed B4 is greater than 2000 rpm. Furthermore, in the range where the rotation speed B4 is 2000 rpm or less, the exhaust pressure can be lowered to less than 20 Pa, for example, to 10 Pa or higher.

[0045] [Table 1]

[0046] As explained in Experiment 2 in Figure 8, the thickness of the resist film R1 across the entire surface of the wafer W is determined according to the rotation speed B4 of the wafer W during the drying period. Therefore, when the processing in the reference example is carried out, the rotation speed B4 is determined so that a resist film R1 with the desired thickness is formed on the wafer W. For example, the rotation speed B4 is determined according to data transmitted to the control unit 100 from a higher-level computer installed in a factory where the substrate processing apparatus 1 is provided, which oversees the operation of the control unit 100.

[0047] However, as mentioned above, the rotation speed B4 is a parameter that changes the thickness of the resist film R1 across the entire surface of the wafer W, as well as a parameter that changes the difference in the thickness of the resist film R1 between the periphery and the center of the wafer W. In order to form a resist film R1 with a desired thickness on the wafer W, the rotation speed B4 may be set to a relatively low value so that the thickness of the resist film R1 at the periphery of the wafer W is relatively large.

[0048] On the other hand, considering the exhaust pressure A2 during the drying period, in order to prevent mist from flowing out of cup 3, it is sufficient to set the exhaust pressure A2 to a relatively high value. As shown in Table 1, when the rotational speed B4 is in the range of 1000 rpm to 4000 rpm, if the exhaust pressure A2 is 20 Pa or higher, it is possible to prevent mist from flowing out of cup 3. In the example process described above, let's assume that the exhaust pressure A2 is set to 20 Pa so that mist does not flow out of cup 3 during the drying period.

[0049] However, as explained in the description of Experiment 2 in Figure 8, the greater the exhaust pressure A2, the less effective it is in reducing the thickness of the resist film R1 at the periphery of the wafer W. Therefore, for wafers W processed with a relatively low rotation speed B4, there is a risk that the thickness at the periphery will be greater than the thickness at the center. If the exhaust pressure A2 is set to a value lower than 20 Pa, for example 10 Pa, in order to suppress this increase in the thickness at the periphery relative to the thickness at the center, there is a risk that mist will flow out of cup 3 when processing wafers W with a rotation speed B4 greater than 2000 rpm.

[0050] Therefore, in the first embodiment, unlike the reference example, the exhaust pressure A2 is set to a value corresponding to the rotation speed B4. More specifically, the exhaust pressure A2 is determined according to the rotation speed B4 before processing the wafer W, and the operation of the damper 47 is controlled so that it becomes the predetermined (set) value. In summary, the setting of the exhaust pressure A2 is set to a relatively low value within the range that prevents mist from flowing out of the cup 3, thereby suppressing an increase in the thickness of the resist film R1 at the periphery of the wafer W. In order to set the exhaust pressure A2 in this way, for example, the correspondence between the rotation speed B4 and the exhaust pressure A2 is obtained from the results of Table 1 of Experiment 3, and the exhaust pressure A2 is set to an appropriate value based on this correspondence and the rotation speed B4. Accordingly, in the processing of this first embodiment, the change in exhaust pressure during the execution of the series of processing steps of the wafer W described in the time chart of Figure 3 is not necessarily the same between wafers W.

[0051] Although the exhaust pressure A2 during the drying period may differ between wafers W, as described in the explanation of the reference example, during the period when the processing liquid is supplied to the wafers W before and after the drying period (the period before time t5 and the period after time t6), it is necessary to prevent the mist generated by the supply of the processing liquid from flowing out of the cup 3. Furthermore, as previously described, setting the exhaust pressure A2 high during the drying period will lead to an increase in the film thickness at the periphery of the wafer W. For this reason, in the processing of this first embodiment, as in the processing of the reference example, the exhaust pressure A2 during the drying period is set lower than the exhaust pressure A1 during the periods before and after the drying period, thereby preventing the scattering of mist outside the cup 3 while preventing a decrease in the uniformity of the film thickness of the resist film R1 in the plane of the wafer W.

[0052] The time chart in Figure 9 shows the processing steps for wafer W in this first embodiment, and, similar to the time chart in Figure 3, it shows the relationship between the change in wafer W rotation speed and the change in exhaust pressure. The processing in the first embodiment is the same as the processing in the reference example, except that the exhaust pressure A2 during the drying period is determined based on the rotation speed B4 and the correspondence between rotation speed B4 and exhaust pressure A2.

[0053] For example, the correspondence between the rotational speed B4 and exhaust pressure A2 described above is stored in the memory that makes up the control unit 100, or in the server to which the control unit 100 is connected. In the following explanation, this correspondence may be referred to as correspondence 1. Specifically, this correspondence 1 is set as follows, for example. If the rotational speed B4 > 2000 rpm, then the exhaust pressure A2 = 20 Pa If the rotational speed B4 ≤ 2000 rpm, then the exhaust pressure A2 = 10 Pa

[0054] The following describes in detail the wafer W processing process in the first embodiment. According to the data received by the control unit 100 from the host computer, if the rotation speed B4 for processing an arbitrary wafer W (let's call it wafer W1) is set to a rotation speed greater than 2000 rpm, the control unit 100 determines the exhaust pressure A2 to be 20 Pa based on this rotation speed B4 and the above correspondence relationship 1. When the wafer W1 is transported to the substrate processing apparatus 1 and held in the spin chuck 21, from time t1 to t5, the rotation speed of the wafer W1 changes and the exhaust pressure is set to A1, and pre-wetting and resist coating proceed on the wafer W1. During the subsequent drying period from time t5 to t6, the wafer W1 rotates at a rotation speed B4 greater than the 2000 rpm set as described above, and the exhaust pressure A2 is set to the determined 20 Pa, and the drying of the resist film R1 proceeds.

[0055] On the other hand, if the rotation speed B4 for processing an arbitrary wafer W (let's call it wafer W2) is set to a rotation speed of 2000 rpm or less, the control unit 100 determines the exhaust pressure A2 to be 10 Pa based on this rotation speed B4 and the above-mentioned correspondence. When the wafer W2 is transported to the substrate processing apparatus 1 and held in the spin chuck 21, from time t1 to t5, the rotation speed of wafer W1 changes as described in the reference example, and the exhaust pressure is set to A1, and pre-wetting and resist coating proceed on wafer W1. During the subsequent drying period from time t5 to t6, wafer W2 rotates at a rotation speed B4 of 2000 rpm or less as set above, and the exhaust pressure A2 is set to the determined 10 Pa, and the drying of the resist film R1 proceeds.

[0056] Both wafer W1, processed with exhaust pressure A2 = 20 Pa, and wafer W2, processed with exhaust pressure A2 = 10 Pa, undergo EBR processing and backside cleaning at times t6 to t8, as explained in the example processing, while the rotation speed changes and the exhaust pressure is set to A1. After drying, the processing is completed.

[0057] During the drying period when processing wafer W1, the relatively high rotation speed B4 suppresses the increase in the thickness of the resist film R1 at the periphery of wafer W1, while the relatively high exhaust pressure A2 of 20 Pa prevents mist from flowing out of cup 3. During the drying period when processing wafer W2, the rotation speed B4 is lower than when processing wafer W1, but the exhaust pressure A2 is also lower than when processing wafer W1, so the effect of this exhaust pressure A2 in reducing the thickness of the resist film at the periphery of wafer W is greater. Therefore, the increase in the thickness of the resist film R1 at the periphery of wafer W2 is also suppressed. Because the rotation speed B4 is relatively low, even with such a low exhaust pressure A2, the outflow of mist to cup 3 is prevented. As described above, according to the processing of the first embodiment, it is possible to prevent mist from flowing out of cup 3 while suppressing the increase in the thickness of the resist film R1 at the periphery of each wafer W, thereby forming a resist film R1 with high uniformity of thickness within the plane of the wafer W.

[0058] Correspondence 1 used to determine exhaust pressure A2 is set as follows, based on the results shown in Table 1 obtained from Experiment 3: "Exhaust pressure A2 = 20 Pa when rotational speed B4 > 2000 rpm" and "Exhaust pressure A2 = 10 Pa when rotational speed B4 ≤ 2000 rpm". If different results are obtained from the experiment, correspondence 1 should be set according to those results. Thus, correspondence 1 is not limited to the examples given, and can be set appropriately according to the characteristics of each device, for example. Even if the results shown in Table 1 are obtained, correspondence 1 is not limited to being set as already explained. For example, from Table 1, when rotational speed B4 ≤ 2000 rpm, exhaust pressure A2 should be lower than 20 Pa and at least 10 Pa, so in this case, exhaust pressure A2 may be set to 15 Pa.

[0059] Furthermore, in the processing steps shown in the chart of Figure 9, the exhaust pressure during the period before the drying period (times t1 to t5) and the exhaust pressure during the period after the drying period (times t6 to t8) are shown to be the same A1. However, the exhaust pressures during these periods may be set to be different from each other. Therefore, in terms of the exhaust volume in cup 3, the first exhaust volume C1 at time t1 to t5 and the third exhaust volume C3 at time t6 to t8 may be set to be different from each other.

[0060] [Second Embodiment] The second embodiment will be described focusing on the differences from the first embodiment. In this second embodiment, similar to the first embodiment, processing steps from pre-wetting to back surface cleaning and EBR processing are performed on the wafer W. Before drying the wafer W by rotation, a cleaning process of cup 3 using the wafer W is performed. Figure 10 is a timing chart showing the relationship between the change in the rotation speed of the wafer W and the change in exhaust pressure in the processing of this second embodiment. After time t6 and before time t7, the discharge of cleaning liquid L2 from the back surface cleaning nozzle 41 stops and the back surface cleaning process of the wafer W is completed. At time t7, the discharge of removal liquid from the removal liquid supply nozzle 61 stops, and the discharge of cleaning liquid L2 to the back surface of the wafer W from the back surface cleaning nozzle 41 resumes. At this time t7, the rotation speed of the wafer W becomes a predetermined rotation speed B6, and the exhaust pressure becomes a predetermined exhaust pressure A3, and the cleaning process of cup 3 begins with the resumed discharge of cleaning liquid L2. Note that the rotation speed B6 may be the same as the rotation speed B5 from time 6 to t7, or it may be greater or less than the rotation speed B5.

[0061] Figure 11 shows a longitudinal cross-sectional side view of the substrate processing apparatus 1 during the cleaning process of cup 3. The cleaning liquid L2 supplied to the back surface of the rotating wafer W splashes inside cup 3, supplying the resist R that has adhered to and solidified in various parts of the cup 3, dissolving and removing the resist R, and cleaning the inside of cup 3. At time t7', a predetermined time has elapsed from time t7, the discharge of the cleaning liquid L2 from the back surface cleaning nozzle 41 stops, and the cleaning process of cup 3 is completed. At this time t7', for example, the rotation speed of the wafer W becomes B1 and the exhaust pressure becomes A1. At time t8, a predetermined time has elapsed from time t7', the rotation of the wafer W stops, and the processing of the wafer W is completed. The period from time t7' to time t8 is the period for drying the wafer W, similar to the period from time t7 to t8 in the first embodiment.

[0062] Let's further explain the cleaning process for cup 3. For the purposes of this explanation, the period from time t7 to t7' during which the cleaning process for cup 3 takes place will be referred to as the cup cleaning period from now on. Depending on the rotation speed B6 of the wafer W during this cup cleaning period, the height at which a relatively large amount of cleaning liquid L2 scattered from the wafer W is supplied within cup 3 changes. More specifically, the region with high cleaning power due to the large amount of cleaning liquid L2 scattered from the wafer W within cup 3 (referred to as the high-cleaning region) is located closer to the top edge of cup 3 as the rotation speed B6 increases. In other words, the height of the high-cleaning region can be changed by changing the rotation speed B6.

[0063] Then, depending on the processing conditions prior to time t7, the height of the region with a relatively large amount of resist R attached to cup 3 (referred to as the highly contaminated region) changes at time t7 when the cleaning process of cup 3 begins. Specifically, for example, the viscosity and specific gravity of the resist may differ depending on the type of resist, so the height of the highly contaminated region changes when the type of resist used for processing wafer W is different (i.e., when the resist supply nozzle 51 used is different). Therefore, the rotation speed B6 of wafer W is set so that the highly contaminated region is included in the highly cleaned region described above. This setting of rotation speed B6 is performed according to data transmitted from the host computer to the control unit 100, similar to the rotation speed B4.

[0064] In this second embodiment, before the start of wafer W processing, in addition to the exhaust pressure A2 being automatically determined according to the rotation speed B4 during the drying period, as in the first embodiment, the exhaust pressure A3 is also automatically determined according to the rotation speed B6 during the cup cleaning period. The opening degree of the damper 47 is adjusted during the cup cleaning period so that the exhaust pressure is set (determined) in advance before the start of processing. The determination of the exhaust pressure A3 is performed based on the correspondence between the rotation speed B6 and the exhaust pressure A3 that has been acquired in advance (for convenience, let's call it correspondence relationship 2), and the exhaust pressure A3 is determined to be a relatively low value within a range that prevents mist from scattering outside the cup 3.

[0065] During the cup cleaning period, regardless of the rotation speed B6, setting the exhaust pressure A3 to a relatively high value can prevent mist from scattering outside the cup 3. However, if the exhaust pressure A3 is always set to a high value, it will waste the limited resources of the factory where the substrate processing device 1 is installed, and there is a risk that the exhaust volume of other substrate processing devices in the factory will be restricted. Therefore, as described above, it is preferable to set the exhaust pressure A3 to a relatively low range while preventing mist from scattering outside the cup 3.

[0066] The memory constituting the control unit 100 and the server to which the control unit 100 is connected store the correspondence relationship 2 between rotational speed B6 and exhaust pressure A3. Specifically, this correspondence relationship 2 is, for example, the relationship described below. This correspondence relationship 2 can also be set according to the experiment performed before processing the wafer W, for example, in the same way as the correspondence relationship 1 described in the first embodiment. When rotational speed B6 > 5000 rpm, exhaust pressure A3 = 80 Pa When rotational speed B6 ≤ 5000 rpm, exhaust pressure A3 = 60 Pa

[0067] When the control unit 100 receives data from the higher-level computer, the rotation speed B6 for the cup cleaning period to process an arbitrary wafer W is set. Based on the set rotation speed B6 and the correspondence relationship 2 described above, the exhaust pressure A3 is determined. Then, when the processing steps shown in the chart of Figure 10 are performed on the wafer W, the rotation speed B6 becomes the set value during the cup cleaning period, and the exhaust pressure A3 becomes the determined value, i.e., 80 Pa or 60 Pa, and the processing proceeds.

[0068] The step in which the exhaust pressure is set to A3 during the cup cleaning period corresponds to the fourth step. As mentioned above, the exhaust pressure A3 is 80 Pa or 60 Pa. Therefore, if the exhaust volume of cup 3 in the fourth step is the fourth exhaust volume C4, then the fourth exhaust volume C4 is set within a range greater than or equal to the largest exhaust volume among the first exhaust volume C1, second exhaust volume C2, and third exhaust volume C3 (i.e., the first exhaust volume C1 and the third exhaust volume C3). In other words, the exhaust pressure A3 in the fourth step is set to be the same as or greater than the largest exhaust pressure in the first to third steps. This is because setting the exhaust pressure A3 in this fourth step relatively high does not affect the film thickness of the resist film R1, and because the rotation speed of the wafer W is relatively high in order to scatter the cleaning liquid L2, it is necessary to set the exhaust pressure A3 relatively high in order to reliably prevent mist from flowing out of cup 3.

[0069] Furthermore, as a second correspondence, when the rotational speed B6 ≤ 5000 rpm, the exhaust pressure A3 is set to 60 Pa. However, this setting is not the only option. As described above, considering the factory's operating power, the exhaust pressure when the rotational speed B6 ≤ 5000 rpm should be less than the exhaust pressure of 80 Pa when the rotational speed B6 > 5000 rpm. Also, as described above, the exhaust pressure A3 in the fourth step should be set to be the same as or greater than the largest exhaust pressure in the first to third steps, so it should be 60 Pa or higher. Therefore, when the rotational speed B6 ≤ 5000 rpm, the exhaust pressure should be, for example, lower than 80 Pa and 60 Pa or higher, and a value higher than the previously mentioned 60 Pa may be used to more reliably prevent mist from flowing outside cup 3, specifically, for example, 70 Pa. Furthermore, as with the first correspondence, the second correspondence is not limited to the examples described above, and the values ​​should be set appropriately according to experiments conducted beforehand.

[0070] Incidentally, regarding correspondence relationship 2, we have explained it as being a correspondence only between rotation speed B6 and exhaust pressure A3, but for example, it can also be a correspondence between the processing conditions of wafer W in the period prior to the cup cleaning period, rotation speed B6, and exhaust pressure A3. Specifically, these processing conditions of wafer W can be, for example, the type of resist used to process wafer W (i.e., the resist supply nozzle 51 used). This is because the specific gravity and viscosity differ depending on the type of resist used, so the height of the highly contaminated area changes, that is, the value of the appropriate rotation speed B6 changes.

[0071] When the correspondence relationship 2 is set in this way, the resist to be used and the rotation speed B6 are set for the wafer W according to the data transmitted from the upper-level computer to the control unit 100, and the exhaust pressure A3 is determined from the correspondence relationship 2 and processing is carried out. In other words, the device configuration may be such that the exhaust pressure A3 is determined according to the rotation speed B6 and the type of resist to be used.

[0072] Furthermore, the height of the highly contaminated region may change depending on the rotation speed B2 during spin coating of the resist R. Therefore, although it was stated that the correspondence relationship 2 can be the correspondence between the processing conditions of the wafer W, the rotation speed B6, and the exhaust pressure A3, the processing condition of the wafer W may also be the rotation speed B2. That is, according to the data transmitted from the upper-level computer to the control unit 100, the rotation speeds B2 and B6 are set, and the exhaust pressure A3 is determined from the correspondence relationship 2 and processing is performed. In other words, the device configuration may be such that the exhaust pressure A3 is determined according to the rotation speeds B2 and B6, respectively.

[0073] In the second embodiment, as in the first embodiment, the exhaust pressure A2 during the drying period is changed based on correspondence relationship 1. However, the exhaust pressure A2 may not be changed based on correspondence relationship 1, and the exhaust pressure A2 may be kept constant between wafers W, similar to the processing in the reference example. Also, in the first and second embodiments, it has been described that the host computer sets the rotation speeds B4 and B6. However, for example, the user of the device may set the rotation speeds B4 and B6 before starting the processing of wafer W. Based on the user's settings, the exhaust pressures A2 and A3 may be determined from correspondence relationships 1 and 2.

[0074] [Variations of the cup] Next, the substrate processing apparatus 1A will be described with reference to the longitudinal cross-sectional side view and the plan view in Figures 12 and 13, respectively. In the plan views of each substrate processing apparatus from Figure 13 onward, the intermediate member 48 adjacent to the wafer W is omitted to avoid cluttering the diagrams. Also, to facilitate visibility in the diagrams, the resist film R1 on the surface of the wafer W is shown with hatching. Therefore, the hatching on the surface of the wafer W does not indicate a cross-section.

[0075] The substrate processing apparatus 1A is configured similarly to the substrate processing apparatus 1, except that it is equipped with cup 3A, which is a modified version of cup 3, instead of cup 3, and is configured to perform the processes described in the first and / or second embodiments. Furthermore, since the same process described for cleaning cup 3 can be performed on cup 3A, the process of the second embodiment can also be performed in this manner.

[0076] Cup 3A differs from Cup 3 in its opening configuration. As described above, the circular opening 34C of Cup 3 is formed to be relatively large. For EBR processing, the removal liquid L1 is discharged to the peripheral edge of the wafer W, that is, to a position relatively close to the opening edge of Cup 3. Therefore, during this EBR processing, there is a risk of splashing, where the removal liquid discharged from the nozzle splashes out of the wafer W as a liquid stream or droplets and scatters outside of Cup 3. Cup 3A is configured to reliably prevent this splashing.

[0077] The differences between cup 3A and cup 3 will now be explained. In cup 3A, only a portion of the tip of the upper wall portion 33 that forms the circular opening 34C, as described in cup 3, protrudes diagonally upward toward the center of cup 3A (i.e., toward the center of the opening 34C), and this protruding portion forms the inclined plate liquid receiving portion 71. In a side view, this liquid receiving portion 71 extends toward the center of cup 3A parallel to the extension direction of the upper wall portion 33, and in a plan view, it is located adjacent to the upper projection 34A and lower projection 34B of the outer cup 31. As described above, the liquid receiving portion 71 is provided so as to block a portion of the periphery of the circular opening 34C in cup 3 in a plan view, and the opening of cup 3A with this portion blocked is shown as opening 34D.

[0078] Figure 14 is a longitudinal cross-sectional side view of the substrate processing apparatus 1A during EBR processing. As shown in Figure 14, the liquid receiving section 71, which is the first liquid receiving section, receives the removal liquid L1 that is discharged from the removal liquid supply nozzle 61 and splashes off the wafer W during EBR processing, thereby preventing splashing, i.e., scattering of the removal liquid L1 outside the cup 3A. As described above, the liquid receiving section 71 is formed to block only a part of the periphery of the circular opening 34C that was formed in the cup 3, so that, similar to the cup 3, the increase in the flow velocity of the airflow near the periphery of the wafer W during processing is suppressed in the cup 3A as well. In other words, even in this cup 3A, variations in the thickness of the resist film R1 in the plane of the wafer W are suppressed.

[0079] The configuration of the liquid receiving section 71 will be described in more detail. As shown in Figure 13, in plan view, the liquid receiving section 71 is in the shape of a wide arc, and is configured such that its length along the circumferential direction of the cup 3A increases towards the peripheral edge of the cup 3A. Let P be the collision point of the removal liquid L1 discharged from the removal liquid supply nozzle 61 on the wafer W. As described above, the liquid receiving section 71 is located near the collision point P in order to receive the removal liquid L1 splashing from the wafer W. In plan view, the liquid receiving section 71 is positioned such that a part of it is located on the extension line P1 (shown by the dashed line) along the discharge direction of the removal liquid L1 from the removal liquid supply nozzle 61 from the collision point P.

[0080] The removal liquid L1 discharged from the removal liquid supply nozzle 61 splashes outwards from the impact point P in a plan view, spreading outwards toward the periphery of the cup 3A, as shown by the dotted line in the figure. The liquid receiving portion 71 is formed such that, as described above, its length along the circumferential direction of the cup 3A increases toward the periphery of the cup 3A in a plan view, so that it can reliably receive the removal liquid L1 that is spreading outwards.

[0081] Furthermore, in order to suppress the flow velocity of the airflow around the periphery of the wafer W during processing, as described above, the circumferential length of the opening 34D of the cup 3A of the liquid receiving portion 71 is formed to be relatively short. Specifically, for example, in a plan view, if the length of the periphery of the opening 34D (i.e., the length of the periphery of the opening 34C) in the case where the liquid receiving portion 71 is not provided is N, then the liquid receiving portion 71 is formed by a portion of the tip of the upper wall portion 33 of the cup 3A with a length of N / 6 or less protruding toward the center of the cup 3A. In other words, if the length of the liquid receiving portion 71 along the periphery of the opening 34D on the periphery side of the cup 3A is N1 (see Figure 13), then N1 ≤ N / 6.

[0082] [Other examples of liquid receiving section configurations] Next, the substrate processing apparatus 1B will be described with reference to the plan view and longitudinal cross-sectional side view in Figures 15 and 16, respectively. The substrate processing apparatus 1B is equipped with a cup 3 and is configured to perform the processes described in the first and second embodiments. It is configured similarly to the substrate processing apparatus 1, except that it is equipped with a sub-processing unit 6A instead of a sub-processing unit 6 as a mechanism for performing EBR processing. The substrate processing apparatus 1B is equipped with a liquid receiving unit 72, similar to the liquid receiving unit 71 of the cup 3A, to receive the removal liquid L1 splashed from the wafer W and prevent it from splashing outside the cup 3. The liquid receiving unit 72, which is the second liquid receiving unit, is provided in the sub-processing unit 6A and moves together with the removal liquid supply nozzle 61 by a moving mechanism 66 provided in the sub-processing unit 6A.

[0083] The sub-processing unit 6A will be explained in detail, focusing on the differences from the sub-processing unit 6. The liquid receiving section 72 is a plate-like member configured in a wide arc shape in plan view, similar to the liquid receiving section 71. However, in the illustrated example, the liquid receiving section 72 has a larger length along the radial direction of the opening 34C than the liquid receiving section 71. In addition, the liquid receiving section 72 is supported, for example, horizontally by a support member 73 provided on the arm 65.

[0084] Figures 15 and 16 show the substrate processing apparatus 1B during EBR processing. When EBR processing is performed (i.e., when the removal liquid L1 is discharged from the removal liquid supply nozzle 61), the liquid receiving section 72 is located near the collision position P where the removal liquid L1 collides with the wafer W, similar to the liquid receiving section 71. In plan view, the liquid receiving section 72 covers a portion of the periphery of the opening 34C of the cup 3, and, similar to the liquid receiving section 71 described above, a portion of the liquid receiving section 72 is located on the extension line P1 along the discharge direction of the removal liquid L1 from the removal liquid supply nozzle 61 from the collision position P. In Figure 15, the extension line P1 is not shown. Hereafter, the positions of the removal liquid supply nozzle 61 and the liquid receiving section 72 during this EBR processing may be referred to as the processing position.

[0085] As shown in Figure 15, in a plan view, the liquid receiving portion 72 in the processing position is positioned such that the center of the cup 3 overlaps with the peripheral edge of the wafer W, and the peripheral edge of the cup 3 overlaps with the upper wall portion 33 of the cup 3. This arrangement of the liquid receiving portion 72 more reliably suppresses the splash. In a side view, the lower surface of the liquid receiving portion 72 in this processing position is close to the upper projection 34A of the upper wall portion 33.

[0086] While the removal liquid supply nozzle 61 is waiting in the opening of the standby section 68, the liquid receiving section 72 is positioned above the standby section 68 and remains in standby mode, and in plan view, the liquid receiving section 72 does not overlap with the opening 34C of the cup 3. Figures 17 and 18 show the plan view and longitudinal cross-sectional side view of the substrate processing apparatus 1B when the removal liquid supply nozzle 61 and the liquid receiving section 72 are in standby mode, respectively. Hereafter, the position in which the removal liquid supply nozzle 61 and the liquid receiving section 72 are in standby mode will be referred to as the standby position.

[0087] A nozzle 74 is provided within the opening of the standby section 68, and pure water, for example, is supplied to the nozzle 74 from the cleaning fluid supply mechanism 75 as a cleaning fluid for the liquid receiving section 72. The cleaning fluid supply mechanism 75 is configured similarly to the processing fluid supply mechanisms such as the cleaning fluid supply mechanism 42 described above, except that it supplies pure water. The nozzle 74 and the cleaning fluid supply mechanism 75 correspond to the cleaning fluid supply section for the liquid receiving section. The nozzle 74 discharges the cleaning fluid from below toward the lower surface of the liquid receiving section 72 in the standby position, removing droplets of the removal fluid L1 adhering to the lower surface of the liquid receiving section 72 and cleaning it. The cleaning fluid is indicated by a dotted arrow in Figure 18. The standby section 68 is provided with a drain port 76 for draining the cleaning fluid discharged from the nozzle 74.

[0088] Furthermore, a nozzle 77 is provided within the opening of the standby section 68, and a gas supply mechanism 78 equipped with a valve or the like supplies gas to the nozzle 77, such as an inert gas or air. After the cleaning liquid is supplied from the nozzle 74, gas is supplied from the nozzle 77 to the lower surface of the liquid receiving section 72 in the standby position, and the lower surface is dried. This cleaning and drying of the lower surface of the liquid receiving section 72 is performed to prevent the removal liquid L1 adhering to the lower surface of the liquid receiving section 72, and the cleaning liquid used to remove the removal liquid L1, from falling onto the wafer W during processing of the wafer W.

[0089] As described above, with the substrate processing apparatus 1B configured, at times t6 to t7 in the chart shown in Figure 9 or Figure 10, the removal liquid supply nozzle 61 and liquid receiving unit 72 are positioned at the respective processing positions shown in Figures 15 and 16, and EBR processing is performed on the wafer W (preceding wafer W). After the EBR processing on the preceding wafer W, the removal liquid supply nozzle 61 and liquid receiving unit 72 move from their respective processing positions to the standby positions shown in Figures 17 and 18 and wait.

[0090] In this standby position, cleaning liquid is supplied from the nozzle 74 to the lower surface of the liquid receiving section 72. Once the removal liquid adhering to the lower surface of the liquid receiving section 72 during the EBR process is removed, gas is then supplied from the nozzle 77 to dry the lower surface. Subsequently, when the next wafer W is transported into the cup 3, at times t6-t7 of the processing step for this next wafer W, the removal liquid supply nozzle 61 and the liquid receiving section 72 are again positioned in their respective processing locations, and the EBR process is performed.

[0091] As described above, when a liquid receiving section 72 is provided that moves together with the removal liquid supply nozzle 61 by the moving mechanism 66, the liquid receiving section 72 can be retracted to a position that does not overlap with the opening 34C of the cup 3 after EBR processing. Therefore, the liquid receiving section 72 does not interfere with the wafer W when loading or unloading the wafer W into or out of the cup 3, so the size of the liquid receiving section 72 in the radial direction of the cup 3 in a plan view can be made relatively large. Therefore, this is preferable because it can more reliably suppress the splash described above.

[0092] Furthermore, since the liquid receiving section 72 moves together with the removal liquid supply nozzle 61, if it is not positioned to overlap with the opening of the cup 3 during the drying period, it is not possible to increase the velocity of the airflow around the periphery of the wafer W, thereby preventing a large variation in the thickness of the resist film R1 within the plane of the wafer W. Accordingly, the liquid receiving section 72 covers only a portion of the periphery of the opening 34C when it is located in the processing position, as shown in the examples in Figures 15 and 16. However, it is not limited to covering only a portion of the periphery, and for example, it may be formed in an annular shape to cover the entire periphery. However, in order to prevent the substrate processing apparatus 1B from becoming larger, it is preferable to configure the liquid receiving section 72 to cover only a portion of the opening 34C. In addition, the liquid receiving section 72 may be connected to an arm separate from the arm 65 that moves the solvent removal nozzle 61, and a separate moving mechanism may be provided to move the liquid receiving section 72 between the standby position and the processing position, in addition to the moving mechanism 65 for moving the arm. In other words, the device may be configured such that a dedicated arm and a dedicated moving mechanism are provided for moving the liquid receiving section 72, and the liquid receiving section 72 can be moved independently of the removal liquid supply nozzle 61.

[0093] The arrangement of the liquid receiving sections 71 and 72 may be changed as appropriate. For example, although the liquid receiving section 71 is shown to be installed at an angle and the liquid receiving section 72 is shown to be installed horizontally, the liquid receiving section 71 may be installed horizontally, or the liquid receiving section 72 may be installed horizontally. Furthermore, the liquid receiving section 71 is not limited to being installed at the height shown so far; for example, it may extend from the height where the upper projection 34A and the lower projection 34B are installed toward the center of the cup 3A. Also, the shape of the liquid receiving sections 71 and 72 is not limited to being arc-shaped in plan view, and may be changed as appropriate from the examples described above.

[0094] Although an example was shown in which a resist is supplied as the coating solution to form a resist film, the coating solution is not limited to resist. For example, an anti-reflective coating can be formed by supplying a chemical solution for forming an anti-reflective coating to wafer W as the coating solution, or an insulating film can be formed by supplying a chemical solution for forming an insulating film to wafer W as the coating solution, or an organic film can be formed by supplying a chemical solution containing organic substances other than resist to wafer W as the coating solution. This technology can also be applied when forming these coating films, such as anti-reflective coatings, insulating films, and organic films.

[0095] In each embodiment, both EBR treatment and back surface cleaning treatment are performed during processing time t6 to t7, but either one or the other may be performed. Accordingly, the substrate processing apparatus may be provided with only one of either a removal liquid supply unit or a cleaning liquid supply unit.

[0096] Furthermore, in each embodiment, the substrate to be processed is not limited to a wafer, but may be, for example, a substrate for manufacturing a flat panel display or a mask substrate for manufacturing a mask for exposure. Therefore, a rectangular substrate may also be processed. The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The above embodiments may be omitted, replaced, modified and combined in various ways without departing from the scope and spirit of the appended claims. [Explanation of Symbols]

[0097] R Resist R1 resist film W wafer 1. Substrate processing device 21 Spin Chuck 3 cups 41 Backside cleaning nozzle 51 Resist supply nozzle 61 Removal fluid supply nozzle 100 Control Unit

Claims

1. A cup that houses the circuit board and allows the inside to be vented, A rotating holding unit that holds and rotates the substrate within the cup, A coating liquid supply unit that supplies a coating liquid to form a coating film on the surface of the substrate, The substrate on which the coating film is formed and which rotates is provided with at least one of the following: a removal liquid supply unit that supplies a removal liquid to remove the coating film from the peripheral edge of the substrate, and a cleaning liquid supply unit that supplies a cleaning liquid to clean the back surface of the substrate. A displacement adjustment unit for adjusting the amount of exhaust in the cup, A control unit that outputs a control signal such that the second exhaust volume is smaller than the first and third exhaust volumes, and the following steps are performed: a first step of exhausting the contents of the cup at a first exhaust volume when the coating liquid is supplied to the substrate; a second step of exhausting the contents of the cup at a second exhaust volume after the coating liquid is supplied to the substrate but before the removal liquid or cleaning liquid is supplied to the substrate; and a third step of exhausting the contents of the cup at a third exhaust volume when the removal liquid or cleaning liquid is supplied to the substrate. A substrate processing apparatus equipped with the following:

2. The removal liquid supply unit and the cleaning liquid supply unit are provided, The second step involves exhausting the contents of the cup at a second exhaust volume before supplying the removal liquid and the cleaning liquid to the substrate. The substrate processing apparatus according to claim 1, wherein the third step is to exhaust the contents of the cup at a third exhaust volume when supplying the removal liquid and the cleaning liquid to the substrate.

3. The control unit, The substrate processing apparatus according to claim 1, wherein the operation of the exhaust volume adjustment unit is controlled according to the rotation speed of the substrate set in the second step.

4. The aforementioned cup is connected to an exhaust passage through which gas flows in from the cup. A pressure detection unit is provided to detect the pressure in the exhaust passage. The substrate processing apparatus according to claim 3, wherein the opening degree of the exhaust passage in the second step is adjusted by the exhaust volume adjustment unit so that the pressure detected by the pressure detection unit becomes a preset pressure.

5. The substrate processing apparatus according to claim 4, wherein the opening of the exhaust passage is adjusted such that, when the rotation speed of the substrate in the second step is 2000 rpm or more, the pressure detected by the pressure detection unit is 20 Pa or more, and when the rotation speed of the substrate in the second step is less than 2000 rpm, the pressure detected by the pressure detection unit is less than 20 Pa and 10 Pa or more.

6. The control unit outputs a control signal so that, after the third step, in order to clean the cup with the cleaning liquid splashed from the rotating substrate, the fourth step is performed, in which the inside of the cup is exhausted at a fourth exhaust volume when the substrate is supplied with only the cleaning liquid from the removal liquid and the cleaning liquid. The substrate processing apparatus according to claim 2, wherein the operation of the exhaust volume adjustment unit is controlled according to the rotation speed of the substrate set in the fourth step.

7. The substrate processing apparatus according to claim 6, wherein the fourth displacement is set in a range greater than or equal to the highest displacement among the first displacement, second displacement, and third displacement, according to the rotation speed of the substrate in the fourth step.

8. The aforementioned cup is connected to an exhaust passage through which gas flows in from the cup. A pressure detection unit is provided to detect the pressure in the exhaust passage. The substrate processing apparatus according to claim 7, wherein the opening degree of the exhaust passage in the fourth step is adjusted by the exhaust volume adjustment unit so that the pressure detected by the pressure detection unit becomes a preset pressure.

9. The substrate processing apparatus according to claim 8, wherein the opening of the exhaust passage is adjusted such that, when the rotation speed of the substrate in the fourth step is 5000 rpm or more, the pressure detected by the pressure detection unit is 80 Pa or more, and when the rotation speed of the substrate in the fourth step is less than 5000 rpm, the pressure detected by the pressure detection unit is less than 80 Pa and 60 Pa or more.

10. The removal liquid supply unit is provided, The substrate processing apparatus according to claim 1, wherein the cup is formed by a part of the periphery of a circular opening protruding toward the center of the cup, and comprises a first liquid receiving portion for receiving the removal liquid splashing from the substrate.

11. The removal liquid supply unit is provided, and the removal liquid supply unit includes a nozzle for supplying the removal liquid to the substrate. A moving mechanism is provided to move the second liquid receiving section, which receives the removal liquid splashing from the substrate, and the nozzle relative to the cup. The substrate processing apparatus according to claim 1, wherein the second liquid receiving portion covers the periphery of the opening of the cup in a plan view when the removal liquid is supplied from the nozzle to the substrate.

12. The substrate processing apparatus according to claim 11, wherein the second liquid receiving portion covers only a portion of the periphery of the opening of the cup in a plan view when the removal liquid is supplied from the nozzle to the substrate.

13. A waiting section is provided outside the cup for holding the nozzle in place. The substrate processing apparatus according to claim 11, wherein the standby unit is further provided with a cleaning liquid supply unit for the liquid receiving unit that supplies cleaning liquid for the liquid receiving unit to the second liquid receiving unit for cleaning while the nozzle is in standby mode in the standby unit.

14. The process of exhausting the inside of the cup containing the circuit board, The process involves holding and rotating the substrate within the cup using a rotating holding unit, A step of supplying a coating liquid from a coating liquid supply unit to form a coating film on the surface of the substrate, A step of performing at least one of the following on the substrate on which the coating film is formed and which is rotating: supplying a removal liquid to the peripheral edge of the substrate using a removal liquid supply unit, and supplying a cleaning liquid to the back surface of the substrate using a cleaning liquid supply unit; The process involves adjusting the amount of exhaust in the cup using the exhaust volume adjustment unit, A first step involves supplying the coating liquid to the substrate and then exhausting the contents of the cup at a first exhaust volume. A second step involves exhausting the contents of the cup at a second exhaust volume after supplying the coating liquid to the substrate but before supplying the removal liquid or cleaning liquid to the substrate. A third step of exhausting the contents of the cup at a third exhaust volume when supplying the removal liquid or cleaning liquid to the substrate, A substrate processing method comprising the following, wherein the second displacement is smaller than the first and third displacements.

15. The process includes supplying a removal liquid to the peripheral edge of the substrate to remove the coating film using a removal liquid supply unit, and supplying a cleaning liquid to the back surface of the substrate using a cleaning liquid supply unit, to the substrate on which the coating film is formed and which is rotating. The second step is to evacuate the inside of the cup at a second exhaust volume before supplying the removal liquid and the cleaning liquid to the substrate. The substrate processing method according to claim 14, wherein the third step is to exhaust the contents of the cup at a third exhaust volume when supplying the removal liquid and the cleaning liquid to the substrate.

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