Substrate processing apparatus, substrate processing method and storage medium

Abstract

The objective of the present invention is to prevent the film-forming liquid, which has become a mist upon impact with the liquid receiving part shaken off from a rotating substrate, from leaking to the outside of the liquid receiving part without increasing the exhaust pressure exhausting the inside of the liquid receiving part. A substrate processing device for processing a substrate according to the present invention comprises a holding rotation unit for holding and rotating a substrate, a supply unit for supplying a film-forming treatment liquid to a substrate held by the holding rotation unit, a liquid receiving unit for receiving the film-forming treatment liquid shaken off from the substrate by rotation by the holding rotation unit, and a control unit for controlling the substrate processing. The liquid receiving unit has a hole at its top through which the substrate held by the holding rotation unit passes and which is an opening to an upper space, and its interior is exhausted. The substrate processing includes a supply process in which a film-forming treatment liquid is supplied to the substrate and the substrate is rotated, and a drying process in which the substrate is rotated after the supply process to dry the film-forming treatment liquid on the substrate. The device further comprises an annular member configured to be able to move in and out with respect to the upper surface of the liquid receiving unit. The control unit controls the annular member to be installed on the upper surface of the liquid receiving unit so as to block the periphery edge of the hole of the liquid receiving unit during the supply process, and to move the annular member away from the upper surface of the liquid receiving unit during the drying process.

Description

Technology Field

[0001] The present disclosure relates to a substrate processing apparatus, a substrate processing method, and a memory medium. Background Technology

[0002] Patent Document 1 discloses a coating device for forming a coating film on a substrate. In this device, while exhausting the processing atmosphere on which the substrate is placed, a resist liquid diluted with a solvent is discharged onto the surface of a substrate rotating around a vertical axis to form a coating film composed of the resist liquid. Subsequently, the exhaust of the processing atmosphere is stopped, and while the solvent atmosphere generated from the resist liquid shaken off from the outer edge of the substrate is formed on the outer periphery of the substrate, the substrate is rotated around a vertical axis and the resist liquid on the surface of the substrate is dried. Prior art literature

[0003] Patent Document 1: Japanese Patent Publication No. 6206316 The problem to be solved

[0004] The technology according to the present disclosure prevents film-forming liquid, which is shaken off from a rotating substrate and becomes mist-like upon impact with a liquid receiving portion, from leaking to the outside of the liquid receiving portion without increasing the exhaust pressure exhausting the interior of the liquid receiving portion. means of solving the problem

[0005] One aspect of the present disclosure is a substrate processing apparatus for processing a substrate, comprising: a holding rotating part for holding and rotating a substrate; a supply part for supplying a film-forming treatment liquid to a substrate held by the holding rotating part; a liquid receiving part for receiving the film-forming treatment liquid shaken off from the substrate by rotation by the holding rotating part; and a control part for controlling the substrate processing. The liquid receiving part has a hole at the top through which the substrate held by the holding rotating part passes and which is an opening to an upper space, and its interior is exhausted. The substrate processing includes a supply process for supplying a film-forming treatment liquid to a substrate and rotating the substrate, and a drying process for rotating the substrate after the supply process to dry the film-forming treatment liquid on the substrate. The apparatus further comprises an annular member configured to be able to move in and out with respect to the upper surface of the liquid receiving part. The control part controls the annular member to be installed on the upper surface of the liquid receiving part so as to block the periphery edge of the hole of the liquid receiving part during the supply process, and to move the annular member away from the upper surface of the liquid receiving part during the drying process. Effects of the invention

[0006] According to the present disclosure, the film treatment liquid that has become a mist upon impact with the liquid receiving portion shaken off from a rotating substrate can be prevented from leaking to the outside of the liquid receiving portion without increasing the exhaust pressure exhausting the inside of the liquid receiving portion. Brief explanation of the drawing

[0007] FIG. 1 is a cross-sectional view schematically showing the configuration of a resist film forming device as a substrate processing device according to the present embodiment. FIG. 2 is a plan view schematically showing the configuration of a resist film forming device as a substrate processing device according to the present embodiment. FIG. 3 is a partially enlarged cross-sectional view schematically showing the configuration of a resist film forming device as a substrate processing device according to the present embodiment. Figure 4 is an explanatory diagram showing the movement of mist particles of a film-forming solution in a conventional substrate processing apparatus. FIG. 5 is an explanatory diagram showing the movement of mist particles of a film-forming solution in a substrate processing apparatus according to the present embodiment. Figure 6 is a graph showing the relationship between the exhaust pressure from the exhaust device and the number of particles of the mist-type film-forming solution detected outside the cup. Figure 7 is a drawing showing another example of a toroidal member. Figure 8 is a drawing showing another example of a toroidal member. Figure 9 is a drawing showing another example of a toroidal member. Figure 10 is a drawing showing a separate example of a toroidal member. Figure 11 is a drawing showing another example of a cup. Figure 12 is a drawing showing another example of a cup. Specific details for implementing the invention

[0008] In the manufacturing process of semiconductor devices, etc., there is a process of forming a desired film, such as a resist film, by supplying a film-forming solution, such as a coating solution, onto a substrate, such as a semiconductor wafer (hereinafter referred to as "wafer"). In this process, so-called spin coating, in which a coating solution is supplied to the substrate and the substrate is rotated to apply the coating solution to the entire substrate by centrifugal force, is widely used (see Patent Document 1). In addition, as a film-forming solution, a pre-wet solution supplied to the substrate before the coating solution is used in addition to the coating solution.

[0009] A substrate processing device used for spin coating comprises a holding rotation unit that holds and rotates a substrate, a supply unit that supplies a film-forming solution to the substrate held by the holding rotation unit, and a liquid receiving unit that receives the film-forming solution shaken off from the substrate by the rotation of the holding rotation unit. An opening is provided at the upper part of the liquid receiving unit to open into an upward space, and the substrate passes through this opening and is placed and held by the holding rotation unit. Additionally, the interior of the liquid receiving unit is exhausted for purposes such as creating a desired airflow on the surface of the substrate held by the holding rotation unit.

[0010] However, there are cases where the film-forming liquid, shaken off from the substrate by rotation, collides with the liquid receiving section and becomes a mist, and this mist-like liquid leaks to the outside of the liquid receiving section through the opening. Since the leaked mist-like liquid adhering to the substrate from the outside of the liquid receiving section can cause defects, it is necessary to prevent such leakage. While such leakage can be prevented by increasing the exhaust pressure evacuating the interior of the liquid receiving section, increasing the exhaust pressure results in higher running costs.

[0011] Accordingly, the technology of the present disclosure prevents the film-forming liquid, which has become a mist upon impact with the liquid receiving portion shaken off from a rotating substrate, from leaking to the outside of the liquid receiving portion without increasing the exhaust pressure exhausting the interior of the liquid receiving portion.

[0012] Hereinafter, a substrate processing apparatus and a substrate processing method according to the present embodiment will be described with reference to the drawings. In addition, in this specification and drawings, redundant descriptions of elements having substantially the same functional configuration are omitted by assigning the same reference numerals.

[0013] FIGS. 1 to 3 are, respectively, a longitudinal section, a plan view, and a partially enlarged cross-sectional view schematically illustrating the configuration of a resist film forming device (1) as a substrate processing device according to the present embodiment.

[0014] The resist film forming device (1) is equipped with a spin chuck (11) as a holding rotating part. The spin chuck (11) holds a wafer (W), and specifically, holds the wafer (W) horizontally by vacuum adsorbing the central back portion of a circular wafer (W) with a diameter of, for example, 300 mm. The spin chuck (11) is connected to a rotating mechanism (12) having an actuator such as a motor. As the spin chuck (11) rotates around a vertical axis by the rotating mechanism (12), the wafer (W) held by the spin chuck (11) also rotates in the same way.

[0015] Additionally, a cup (14) serving as a liquid receiving portion is installed to surround the wafer (W) held in the spin chuck (11). The cup (14) can receive and recover film-forming liquids, such as coating liquid or pre-wet liquid, that are shaken off from the wafer (W) by rotation of the spin chuck (11).

[0016] An exhaust port (15) is provided at the bottom of the cup (14). Additionally, an exhaust pipe (16) is installed at the bottom of the cup (14), and an exhaust mechanism (30) having an exhaust pump or the like is connected to the exhaust pipe (16). During the processing of the wafer (W), the interior of the cup (14) is exhausted through the exhaust pipe (16) by the exhaust mechanism (30). By exhausting from within the cup (14), exhaust is performed on the surface of the wafer (W) from the surroundings of the wafer (W).

[0017] Additionally, the cup (14) has a circular hole (17) on its upper side when viewed in a planar view, which is concentric with the spin chuck (11). This hole (17) becomes an opening for the space above the cup (14). A wafer (W) passes through this opening (17) and is placed and held in the spin chuck (11).

[0018] Additionally, the cup (14) has a side wall (18) to which the processing liquid, which is laterally shaken off from the wafer (W) by rotation by the spin chuck (11), collides. The side wall (18) includes a cylindrical circumferential wall (18a) extending in the vertical direction and an inclined wall (18b) extending along the entire circumferential direction inwardly upward from the top of the circumferential wall (18a). The inclined wall (18b) is located to the side of the wafer (W) held in the spin chuck (11), and the processing liquid, which is laterally shaken off from the wafer (W), collides with the inclined wall (18b).

[0019] Additionally, the cup (14) has a ceiling wall (19) that is annular when viewed in a plan view, extending horizontally from the side wall (18) toward the inside to form a hole (17). In the example of the drawing, the ceiling wall (19) is connected to the top of the inclined wall (18b). The ceiling wall (19) may also be shaped to extend from the side wall (18) toward the inside upward at an angle closer to horizontal than the side wall (18) to the inside upward.

[0020] In addition, when viewed in the plan view, the inner end of the circular ceiling wall (19) is provided with a convex portion (20) that extends vertically upward along the entire circumference along the inner end.

[0021] Around the spin chuck (11) inside the cup (14), a ring-shaped guide member (21) having beveled portions (21a, 21b) on the inside and outside is disposed. A bevel cleaning nozzle (24) is installed at the top of the guide member (21). The bevel cleaning nozzle (24) discharges a solvent of resist liquid onto the periphery edge of the back surface of the wafer (W) to clean the bevel portion of the wafer (W). The bevel cleaning nozzle (24) is connected to a solvent supply mechanism (not shown). This solvent supply mechanism is equipped with a pump or valve, etc., to supply a solvent of resist liquid to the bevel cleaning nozzle (24).

[0022] Additionally, a lifting pin (31) is arranged around the spin chuck (11). This lifting pin (31) is raised in a vertical direction by a lifting mechanism (32) having an actuator such as a cylinder, and can support and raise a wafer (W). By doing so, the wafer (W) can be transferred between the spin chuck (11) and a wafer transport mechanism (not shown).

[0023] A fan filter unit (FFU) (31) as an airflow forming unit is installed above the hole (17) of the cup (14) and forms a downward airflow of clean air as a clean gas, supplying the air into the cup (14) through the hole (17). The clean air supplied to the wafer (W) inside the cup (14) is exhausted out of the cup (14) by the exhaust mechanism (30).

[0024] Additionally, the resist film forming device (1) is equipped with a resist liquid supply nozzle (41) and a solvent supply nozzle (51) as a supply unit for supplying a film forming liquid to a wafer (W) held in a spin chuck (11), as shown in FIGS. 1 and 2.

[0025] The resist liquid supply nozzle (41) discharges the resist liquid as a coating liquid, for example, in a vertical downward direction. This resist liquid supply nozzle (41) is connected to a resist supply mechanism (42). The resist supply mechanism (42) is equipped with a pump or valve, etc., to supply the resist liquid to the resist liquid supply nozzle (41).

[0026] As shown in FIG. 2, the resist liquid supply nozzle (41) is supported at the tip of the arm (43), and the base of the arm (43) is connected to a moving mechanism (44). The moving mechanism (44) can move along the guide rail (45) in the direction of the reciprocating arrow in the drawing by means of an actuator such as a motor. Additionally, the resist liquid supply nozzle (41) supported by the arm (43) can move in a vertical direction. The resist liquid supply nozzle (41) can be placed in a standby section (46) positioned on the outside of the cup (14).

[0027] The solvent supply nozzle (51) discharges an organic solvent as a pre-wet liquid, for example, in a vertical downward direction. This solvent supply nozzle (51) is connected to a solvent supply mechanism (52). The solvent supply mechanism (52) is equipped with a pump or valve, etc., to supply the organic solvent to the solvent supply nozzle (51).

[0028] The solvent supply nozzle (51) is supported at the tip of the arm (53), and the base of the arm (53) is connected to a moving mechanism (54). The moving mechanism (54) can move along the guide rail (55) in the direction of the reciprocating arrow in the drawing by means of an actuator such as a motor. Additionally, the solvent supply nozzle (51) supported by the arm (53) can move in a vertical direction. The solvent supply nozzle (51) can be in a waiting area (56) positioned on the outside of the cup (14).

[0029] In addition, the resist film forming device (1) is equipped with a toroidal member (60) that is toroidal when viewed in a plan view, as shown in FIGS. 1 and 2.

[0030] In a conventional resist film forming device that does not have a ring member (60), if the exhaust pressure for exhausting the inside of the cup (14) is not increased, the film forming liquid, which is shaken off from the wafer (W) by rotation and collides with the inner circumference of the inclined wall (18b) of the cup (14) to become a mist, may leak out of the cup (14) through the hole (17).

[0031] Regarding this leakage, the inventors have superimposed simulations and found the following: that is, even in the conventional resist film forming apparatus, if the diameter of the hole (17) of the cup (14) is made smaller than the wafer (W), for example, 240 mm, it is found that the mist-type film forming liquid can be prevented from leaking outside the cup (14) without increasing the exhaust pressure. However, in reality, the diameter of the hole (17) of the cup (14) cannot be made smaller than the wafer (W). This is because it is not possible to place the wafer (W) onto the spin chuck (11) through the hole (17) from the outside of the cup (14).

[0032] Accordingly, in this embodiment, a toroidal member (60) is installed as described above.

[0033] The toroidal member (60) forms a hole (60a) in its center that is smaller in diameter than the hole (17) of the cup (14). Additionally, the toroidal member (60) is connected to a lifting mechanism (62) that serves as a retraction mechanism, having an actuator such as a cylinder, through a support member (61). By means of the lifting mechanism (62), the toroidal member (60) is made to be able to move up and down relative to the upper surface of the cup (14), specifically, between a first position indicated by a dashed line in FIG. 1 and a second position indicated by a solid line in FIG. 1. The first position is a position where the toroidal member (60) is installed on the upper surface of the cup (14) so ​​as to block the entire circumference of the hole (17) of the cup (14). The second position is a position above the first position and is a position that does not interfere with the wafer (W) during transfer between the wafer transport mechanism (not shown) and the spin chuck (11) through the lifting pin (31). Also, in this example, at both the first and second positions, the toroidal member (60) is concentric with the hole (17) of the cup (14) and the spin chuck (11) [wafer (W) held in the spin chuck].

[0034] When a mist-type film-forming liquid is produced, the annular member (60) is installed on the upper surface (14a) of the cup (14) [specifically, the upper surface of the ceiling wall (19)] as shown in FIG. 3, that is, it is positioned at the aforementioned first position (lower position). When positioned at the first position in this way, the annular member (60) blocks the periphery edge of the hole (17) of the cup (14) and extends inwardly from the inner end of the ceiling wall (19) forming the hole (17). That is, by positioning the annular member (60) at the first position (lower position), the opening to the upper space of the cup (14) is reduced in diameter from the hole (17) of the cup (14) to the hole (60a) of the annular member (60), which has a smaller diameter than the hole (17). Therefore, a cup (14) with a small diameter of the hole (17) can be similarly realized.

[0035] Meanwhile, the toroidal member (60) is positioned at the aforementioned second position (upper position) when transferring the wafer (W) between the wafer transport mechanism (not shown) via the lifting pin (31) and the spin chuck (11). Therefore, when transferring the wafer (W), the toroidal member (60) and the wafer (W) do not interfere with each other. Additionally, the toroidal member (60) is positioned at the second position (upper position) even when no mist-type film-forming liquid is generated, other than during transfer.

[0036] Additionally, the annular member (60) has a circumferential edge cover portion (100) and a connecting portion (110), as shown in FIGS. 2 and 3.

[0037] The perimeter edge cover portion (100) is formed in the shape of a toroidal plate and is positioned horizontally. The outer diameter of the perimeter edge cover portion (100) is slightly smaller than the diameter of the hole (17) of the cup (14), and the inner diameter of the perimeter edge cover portion (100) is smaller than the diameter of the wafer (W), for example, 140 to 260 mm. Additionally, the perimeter edge cover portion (100) is positioned concentrically with the spin chuck (11) [wafer (W) held in the spin chuck] and the hole (17) of the cup (14) when viewed in a plan view. Then, when the toroidal member (60) is in the aforementioned first position, the perimeter edge cover portion (100) covers the entire circumference of the hole (17) of the cup (14) and extends inwardly from the inner end of the ceiling wall (19) forming the hole (17). Also, the lower surface of the perimeter edge cover part (100) of this example is horizontal.

[0038] The connecting portion (110) connects the perimeter edge cover portion (100) and the support member (61). This connecting portion (110) is formed to extend outward from the outer edge of the perimeter edge cover portion (100) when viewed in a plan view, over the entire perimeter. Additionally, the connecting portion (110) has a shape that follows the inner circumference portion at the top of the cup (14) when the annular member (60) is in the aforementioned first position [specifically, a shape that follows the inner circumference upper surface of the ceiling wall (19) and the outer circumference, upper surface, and inner circumference of the convex portion (20)]. Specifically, for example, the connecting portion (110) has a curved surface (110a) that is curved to correspond to the shape of the inner circumference portion at the top of the cup (14), and the convex portion (20) of the cup (14) can be accommodated in the concave portion formed by the curved surface (110a). Since the connecting part (110) is configured as described above, when the toroidal member (60) is placed in the first position described above, the gap between the toroidal member (60) and the cup (14) is reduced.

[0039] Additionally, a control unit (U) is installed in the resist film forming device (1). The control unit (U) is a computer equipped with, for example, a CPU or memory, and has a program storage unit (not shown). The program storage unit stores a program that controls the processing of the wafer (W) in the resist film forming device (1). The stored program contains commands (each step) to control the operation by transmitting control signals to each part of the resist film forming device (1). For example, the control unit (U) controls the change in the rotation speed of the spin chuck (11) by the rotation mechanism (12), that is, the rotation speed (rotation speed) of the wafer (W), and the movement of the resist liquid supply nozzle (41) and the solvent supply nozzle (51). Additionally, the control unit (U) controls the supply and stopping of resist liquid from the resist supply mechanism (42) to the resist liquid supply nozzle (41), the supply and stopping of solvent from the solvent supply mechanism (52) to the solvent supply nozzle (51), and the supply and stopping of the resist liquid solvent from the solvent supply mechanism (not shown) to the bevel cleaning nozzle (24). Additionally, the control unit (U) controls the lifting and lowering of the ring member (60) and the amount of exhaust by the exhaust mechanism (30). Furthermore, the aforementioned program may be recorded on a non-transient storage medium readable by a computer and may be installed on the control unit (U) from said storage medium. Part or all of the program may be implemented on dedicated hardware (circuit board).

[0040] Next, an example of a method for forming a resist film using a resist film forming device (1) will be described.

[0041] (Placement and adsorption maintenance of wafer (W))

[0042] First, a wafer (W) is placed on the spin chuck (11) and held in place by adsorption. Specifically, a wafer transport device (not shown) holding the wafer (W) is inserted into the interior of the resist film forming device (1), and the wafer (W) is transferred between the wafer transport device and the spin chuck (11) via a lifting pin (31) and thereby placed on the spin chuck (11). After that, the wafer (W) is held in place by adsorption on the spin chuck (11).

[0043] In this process, the toroidal member (60) is located at the aforementioned second position (rising position). Also, the second position (rising position) is a position where the wafer (W), the wafer transport device, and the toroidal member (60) do not interfere during the transfer of the aforementioned wafer (W), and where the toroidal member (60) and the FFU (31) do not interfere. The second position (rising position) is, for example, a position 40 to 70 mm from the wafer (W) held on the spin chuck (11).

[0044] (Free Wet)

[0045] Next, a pre-wet treatment is performed on the wafer (W). Specifically, a solvent supply nozzle (51) is moved upward to the center of the wafer (W) held in the spin chuck (11), and an organic solvent is supplied onto the wafer (W) from the solvent supply nozzle (51). In addition, the wafer (W) is rotated at a high rotational speed, for example, 2000 rpm or higher. In this example, the rotational speed of the wafer (W) is set to 2000 rpm. Furthermore, in this process, the exhaust pressure for exhausting the inside of the cup (14) is, for example, 21 Pa.

[0046] During the pre-wet treatment, since the rotation speed of the wafer (W) is high as described above, the pre-wet liquid shaken off from the wafer (W) collides with the cup (14), creating a mist-type pre-wet liquid. Therefore, in this process, the ring member (60) is positioned at the aforementioned first position (lower position). By doing so, the opening in the space above the cup (14) is made smaller, so that the mist-type pre-wet liquid does not leak through the opening.

[0047] (Resist liquid film formation)

[0048] Next, a resist liquid film forming process is performed to form a resist liquid film on the wafer (W). Specifically, after retracting the solvent supply nozzle (51), the resist liquid supply nozzle (41) is moved upward toward the center of the wafer (W) held in the spin chuck (11), and the resist liquid is supplied onto the wafer (W) from the resist liquid supply nozzle (41). In addition, the wafer (W) is rotated at a high rotational speed, for example, 2000 rpm or higher. By doing so, a resist liquid film covering the entire upper surface of the wafer (W) is formed. Also, in this example, the rotational speed of the wafer (W) is set to 2500 rpm. Furthermore, in this process as well, the exhaust pressure exhausting the inside of the cup (14) is, for example, 21 Pa.

[0049] During the process of forming a resist liquid film, as the rotation speed of the wafer (W) is high as described above, the resist liquid shaken off from the wafer (W) collides with the cup (14), creating a mist-type resist liquid. Therefore, in this process, following the process of performing a pre-wet treatment, the ring member (60) is positioned at a first position (lower position). By doing so, the diameter of the opening in the space above the cup (14) is reduced, making it difficult for the mist-type resist liquid to leak through the opening.

[0050] (dry)

[0051] Next, a process is performed on the wafer (W) to dry the liquid film of the resist liquid and form a resist film on the wafer (W). Specifically, the resist liquid supply nozzle (41) is retracted, and the wafer (W) is rotated at a low rotational speed, for example, 1500 rpm or less. By doing so, the liquid film of the resist liquid on the wafer is dried while shaking off excess resist liquid to form a resist film. Also, in this example, the rotational speed of the wafer (W) is set to 1500 rpm. In addition, in this process as well, the exhaust pressure exhausting the inside of the cup (14) is, for example, 21 Pa. In other words, the exhaust pressure does not change during the pre-wet treatment, the resist liquid film formation treatment, and the drying treatment.

[0052] During the drying process, since the rotation speed of the wafer (W) is low as described above, the resist liquid shaken off from the wafer (W) does not collide with the cup (14), so no mist-type resist liquid is formed. Additionally, during the drying process, the airflow formed on the surface of the wafer (W) by the exhaust of air from the FFU (31) affects the shape of the resist film. Therefore, if the ring member (60) is positioned at the aforementioned first position (downward position) during the drying process, it has an adverse effect on the film thickness distribution of the resist film, such as the resist film becoming thicker only at the periphery edge. Accordingly, in this process, the position of the ring member (60) becomes the aforementioned second position (upward position).

[0053] (Bevel cleaning)

[0054] After that, a cleaning process is performed on the bevel portion of the wafer (W). Specifically, the bevel cleaning nozzle (24) supplies a solvent of resist liquid to the perimeter edge portion of the back side of the wafer (W). At the same time, the wafer (W) is rotated. By doing so, unnecessary resist film is removed from the perimeter edge portion of the back side of the wafer (W) and the bevel portion.

[0055] (Export)

[0056] Then, the wafer (W) is removed from the resist film forming device (1) in the reverse order of the wafer (W) placement and adsorption maintenance process.

[0057] As described above, in this embodiment, the resist film forming device (1) is provided with a toroidal toroidal member (60) configured to be vertically movable with respect to the upper surface of the cup (14).

[0058] In the supply process (i.e., the aforementioned pre-wet treatment and resist liquid film formation process) in which a film-forming liquid is supplied to a wafer (W) by this resist film forming device (1) and the wafer (W) is rotated, the rotation speed of the wafer (W) is high because it is necessary to spread the film-forming liquid over the entire upper surface of the wafer (W). Therefore, in the supply process, the film-forming liquid shaken off from the wafer (W) may collide with the cup (14) and become a mist.

[0059] In the case where the ring member (60) is not installed as in the present embodiment, as shown in FIG. 4, the distance from the location where the film-forming liquid in the cup (14) collides, i.e., the location where the mist-type film-forming liquid is generated, to the edge of the hole (17), which is an opening in the space above the cup (14) in this case, is short. Also, because the gap between the lower surface of the ceiling wall (19) and the surface of the wafer (W) is large, the flow rate of clean air from the FFU (31) passing through the gap tends to be slow. Therefore, during the supply process, if the exhaust pressure by the exhaust mechanism (30) is not increased, the mist particles (M) of the film-forming liquid may not be discharged together with the gas discharged from inside the cup (14) and may reach the edge of the opening [i.e., the edge of the hole (17)]. Therefore, there are cases where the mist-type membrane treatment liquid leaks out of the cup (14) through the opening, i.e., the hole (17).

[0060] In contrast, in the present embodiment, a ring member (60) is installed, and during the supply process, this ring member (60) becomes the aforementioned first position (lower position). That is, during the supply process, the ring member (60) is installed on the upper surface (14a) of the cup (14) to block the circumferential edge of the hole (17) of the cup (14). Therefore, during the supply process, the opening to the space above the cup (14) becomes the hole (60a) formed by the ring member (60), which is smaller than the hole (17). As a result, as shown in FIG. 5, the distance from the position where the mist of the film-forming liquid is generated to the edge of the opening to the space above the cup (14) [i.e., the edge of the hole (60a)] is increased. In addition, because the gap between the lower surface of the circular member (60) [specifically, the lower surface of the circumferential edge cover part (100)] and the surface of the wafer (W) is small, the flow rate of clean air from the FFU (31) passing through the gap tends to be fast. Therefore, during the supply process, even if the exhaust pressure by the exhaust mechanism (30) is not increased, the mist particles (M) of the film-forming liquid do not reach the edge of the opening [i.e., the edge of the hole (60a)] and are discharged together with the gas discharged from the inside of the cup (14). Therefore, according to this embodiment, even if the exhaust pressure by the exhaust mechanism (30) [i.e., the exhaust pressure exhausting the inside of the cup (14)] is not increased, the mist-type film-forming liquid does not leak out of the cup (14) during the supply process. In addition, if the exhaust pressure by the exhaust mechanism (30) during the above supply process is increased, the mist-type film-forming liquid can be more reliably prevented from leaking out of the cup (14) during the above supply process. That is, according to the present embodiment, the mist-type film-forming liquid can be efficiently prevented from leaking out of the cup (14) during the above supply process.

[0061] In addition, in this embodiment, during the drying process, the toroidal member (60) becomes the aforementioned second position (upper position) and is spaced apart from the upper surface (14a) of the cup (14). Therefore, the toroidal member (60) does not adversely affect the film thickness distribution of the resist film on the wafer (W).

[0062] In addition, if a circular disc member is used in a plan view having a diameter equal to the outer diameter of the circular member (60) instead of the toroidal member (60), clean air from the FFU (31) is not introduced into the interior of the cup (14) during the resist liquid film formation process. As a result, the film thickness of the resist film becomes uneven within the plane. Therefore, the circular member (60) is used instead of the disc member as described above.

[0063] The results of actual tests conducted by the inventors on the toroidal member (60) are shown in the graph of FIG. 6. In the tests conducted by the inventors, both the aforementioned pre-wet treatment and the resist liquid film formation treatment were performed. Additionally, the rotation speed of the wafer (W) during the pre-wet treatment and the resist liquid film formation treatment was set to 4000 rpm. In the graph of FIG. 6, the horizontal axis represents the exhaust pressure by the exhaust mechanism (30), and the vertical axis represents the number of particles of the mist-type film formation treatment liquid (both organic solvent and resist liquid) detected outside the cup (14).

[0064] As shown in FIG. 6, when the ring member (60) is absent, mist particles of the film-forming liquid were detected outside the cup (14) even when the exhaust pressure was increased to 60 Pa. According to tests conducted by the inventors, in order to prevent mist particles of the film-forming liquid from being detected outside the cup (14) when the ring member (60) is absent, a very high exhaust pressure of 65 Pa or higher was required.

[0065] In contrast, when a ring member (60) with an inner diameter of 240 mm is installed and the ring member (60) is positioned at the aforementioned first position (downward position) during pre-wet treatment and resist liquid film formation treatment, mist particles of the film-forming liquid are not detected outside the cup (14) even if the exhaust pressure is low at 15 Pa or 10 Pa.

[0066] In addition, when a ring member (60) with an inner diameter of 260 mm was installed, mist particles of the film-forming liquid were not detected outside the cup (14) even if the exhaust pressure was low at 25 Pa to 30 Pa. Also, when a ring member (60) with an inner diameter of 280 mm was installed, a relatively high exhaust pressure of 35 Pa or higher was required to prevent mist particles of the film-forming liquid from being detected outside the cup (14).

[0067] Therefore, it is preferable that the inner diameter of the annular member (60) be 260 mm or less.

[0068] In addition, according to tests conducted by the inventors, even when the inner diameter of the ring member (60) is smaller than 240 mm, a mist-type film-forming liquid was not detected outside the cup (14) at low exhaust pressure, just as when it was 240 mm. However, when a ring member (60) with an inner diameter smaller than 140 mm was installed, the film thickness distribution of the resist film formed on the wafer (W) after drying treatment deteriorated. This is considered to be because, during drying treatment, clean air from the FFU (31) cannot be sufficiently blown into the inside of the cup (14), and thus a desired airflow cannot be formed on the upper surface of the wafer (W).

[0069] Therefore, it is preferable that the inner diameter of the annular member (60) be 140 mm or more.

[0070] Additionally, for the material of the toroidal member (60), for example, a resin material is used. By making the material of the toroidal member (60) a resin material, compared to the case where a metal material is used, the temperature drop of the toroidal member (60) due to the vaporization of the mist-type film-forming treatment liquid when the treatment is repeated can be suppressed, and thus the toroidal member (60) can be prevented from condensing.

[0071] In addition, in this embodiment, the connecting portion (110) of the annular member (60) has a shape that follows the inner circumferential portion at the top of the cup (14) when the annular member (60) is placed in the aforementioned first position (downward position) [specifically, a shape that follows the inner circumferential upper surface of the ceiling wall (19) and the outer surface, upper surface, and inner surface of the convex portion (20)]. By doing so, when the annular member (60) is placed in the aforementioned first position (downward position), the gap between the annular member (60) and the cup (14) is reduced. If the gap is reduced in this way, it is possible to prevent the mist-type film-forming liquid from leaking to the outside of the cup (14) through the gap. To more reliably prevent leakage through the gap, it is preferable that the annular member (60) and the cup (14) be in close contact when the annular member (60) is placed in the aforementioned first position (downward position). However, if they are in close contact like this, there is a risk that dust will be generated due to friction with the cup (14) when the ring member (60) is raised or lowered.

[0072] In addition, in the above example, the annular member (60) was moved up and down relative to the aforementioned first position (downward position) [i.e., relative to the upper surface of the cup (14)]. That is, in the above example, the direction of the annular member (60) moving up and down relative to the aforementioned first position was vertical. The direction of the moving and down may be approximately horizontal. Also, if the direction of the moving and down is not vertical, and the position when the annular member (60) is retracted from the aforementioned first position is a position that does not hinder the clean gas from the FFU (31) from moving toward the cup (14) by the annular member (60), the inner diameter of the annular member (60) may be less than 140 mm.

[0073] Figures 7 to 9 are drawings showing different examples of toroidal members, respectively.

[0074] In the above example, the lower surface of the annular member (60) [specifically, the lower surface (100a) of the circumferential edge cover portion (100)], that is, the surface facing the wafer (W) held in the spin chuck (11), was horizontal. The shape of the lower surface of the annular member (60) is not limited to this. For example, it may be an inclined surface that gradually slopes downward from the outer side (outer end in the example of FIG. 7) toward the inner end, such as the lower surface (201a) of the circumferential edge cover portion (201) of the annular member (200) in FIG. 7. As a result, when the annular member (200) is placed in the aforementioned first position (downward position), the gap between the annular member (200) and the wafer (W) becomes smaller. Consequently, the flow velocity of the clean air supplied from the FFU (31) as it flows through the gap increases. Therefore, it is possible to more reliably prevent the mist-type film treatment liquid from reaching the hole (60a) formed by the annular member (200) and leaking out of the cup (14) through the hole (60a).

[0075] Additionally, as shown in FIG. 8, the annular member (210) may have a convex portion (212) formed in an annular shape concentric with the annular member (210) on the inner circumference side of the lower surface (211a) of the circumferential edge cover portion (211) and protruding toward the wafer (W) held in the spin chuck (11). By doing so, when the annular member (210) is placed in the aforementioned first position (lower position), the gap between the annular member (210) and the wafer (W) becomes smaller. As a result, the flow velocity of the clean air supplied from the FFU (31) as it flows through the gap increases. Therefore, it is possible to more reliably prevent the mist-type film-forming liquid from reaching the hole (60a) formed by the annular member (210) and leaking out of the cup (14) through the hole (60a).

[0076] Additionally, as shown in FIG. 9, the annular member (220) may have the inner end of the circumferential edge cover portion (221) formed thicker in the vertical direction than the convex portion (20), and the entire upper surface (222) may be a horizontal flat surface. Furthermore, the inner end of the upper surface (222) of the annular member (220) may be located inward from the outer end of the wafer (W) held in the spin chuck (11), and the outer end of the upper surface (222) may be located outward from the outer end of the hole (17) of the cup (14). As a result, the downward rectification action at the inner end of the circumferential edge cover portion (221) is strengthened and it becomes easier to draw in surrounding air, so that clean air supplied from the FFU (31) does not stay on the upper surface (222) of the annular member (220) or move outward, and is easily introduced into the interior of the cup (14). As a result, the amount of clean air supplied from the FFU (31) introduced into the interior of the cup (14) increases. Therefore, the mist-type film treatment liquid can be more reliably prevented from reaching the hole (60a) formed by the circular member (220) and leaking out of the cup (14) through the hole (60a).

[0077] Figure 10 is a drawing showing a separate example of a toroidal member.

[0078] Even if the annular member (60) is positioned at the aforementioned first position (lower position) and the perimeter edge of the hole (17) of the cup (14) is covered by the perimeter edge cover portion (100), there may be cases where a mist-type film-forming liquid leaks out of the cup (14) through the gap between the annular member (60) and the cup (14). To suppress this leakage, as shown in FIG. 10, a labyrinth structure (R) may be formed on the surface (230a) facing the upper surface (14a) of the cup (14) at the annular member (230) that has become the aforementioned first position (lower position) and on the upper surface (14a) of the cup (14). In other words, a labyrinth structure (R) may be formed on the upper surface (14a) of the cup (14) and on the upper surface (14a) of the cup (14) at the annular member (230) installed on the upper surface (14a) of the cup (14). The labyrinth structure (R) of the example drawing is composed of a plurality of (specifically two) upwardly recessed concave portions formed by the upwardly recessed concave portion (230a) of the annular member (230), and a plurality of (specifically two) convex portions (300) protruding upwardly from the upper surface (14a) to be received in each of the said concave portions of the cup (14).

[0079] Figure 11 is a drawing showing another example of a cup.

[0080] The cup (400) of FIG. 11 has a sealing portion (401). The sealing portion (401) seals the space between the outer circumference of the annular member (240) and the upper surface (14a) of the cup (400) [specifically, the upper surface of the ceiling wall (19)], and is formed on the upper surface (14a). This sealing portion (401) has a groove (402) in which the lower end of the outer circumference of the annular member (240), which is in the aforementioned first position (lower position), is received, and the groove (402) is filled with water (403). The groove (402) is formed to be concentric with the hole (17) of the cup (14) when viewed in a plan view. By installing such a seal (401), it is possible to prevent the mist-type film treatment liquid from leaking out of the cup (400) through the gap between the circular member (240) and the cup (400).

[0081] Figure 12 is a drawing showing another example of a cup.

[0082] The cup (500) of FIG. 12 has a suction passage (501) as a suction part. The suction passage (501) is for sucking gas in the gap between the toroidal member (240) and the cup (500). The suction passage (501) is formed within the wall forming the cup (500), specifically, it is formed within the ceiling wall (19) and the inclined wall (18b) so as to extend across the ceiling wall (19) and the inclined wall (18b). One end of the suction passage (501) is open to the space between the toroidal member (240) and the cup (500), and the other end of the suction passage (501) is connected to a suction mechanism (not shown) having a suction pump.

[0083] Additionally, the cup (500) has a groove (502) in which the lower outer circumference of the annular member (240), which has become the first position (lower position) described above, is received. The groove (502) is formed to be concentric with the hole (17) of the cup (14) when viewed in a planar view. The upper end of the suction path (501) is, for example, connected to this groove (502).

[0084] As described above, by installing a suction channel (501), it is possible to prevent the mist-type film treatment liquid from leaking out of the cup (500) through the gap between the circular member (240) and the cup (500).

[0085] In addition, a suction part for sucking gas in the gap between the toroidal member and the cup may be installed on the toroidal member.

[0086] The embodiments disclosed herein should be regarded as illustrative in all respects and not restrictive. The above embodiments may be omitted, substituted, or modified in various forms without departing from the appended claims and their common meaning.

Claims

Claim 1 A substrate processing device for processing a substrate comprises: a holding rotating part that holds and rotates a substrate; a supply part that supplies a film-forming treatment liquid to a substrate held by the holding rotating part; a liquid receiving part that receives the film-forming treatment liquid shaken off from the substrate by rotation by the holding rotating part; and a control part that performs control regarding substrate processing. The liquid receiving part has a hole at the top through which the substrate held by the holding rotating part passes and which becomes an opening for an upper space, and its interior is exhausted. The substrate processing includes a supply process that supplies a film-forming treatment liquid to the substrate and rotates the substrate, and a drying process that, after the supply process, rotates the substrate to dry the film-forming treatment liquid on the substrate. It further includes an annular member configured to be able to move in and out with respect to the upper surface of the liquid receiving part. The control part is installed on the upper surface of the liquid receiving part so that the annular member blocks the periphery edge of the hole of the liquid receiving part during the supply process, and performs control so that the annular member retracts from the upper surface of the liquid receiving part during the drying process. The annular member is the holding A substrate processing apparatus in which the surface facing the substrate maintained in the rotating part is an inclined surface that gradually slopes downward from the outer side toward the inner end. Claim 2 A substrate processing device according to claim 1, wherein the liquid receiving portion has a ceiling wall forming the hole, and the annular member is in a state of extending inwardly from the inner end of the ceiling wall when installed on the upper surface of the liquid receiving portion. Claim 3 A substrate processing device according to paragraph 2, wherein the liquid receiving portion has a side wall to which the processing liquid shaken laterally from the substrate collides, and the ceiling wall extends from the side wall at an angle closer to horizontal than the side wall. Claim 4 A substrate processing device according to claim 1, wherein the annular member has an upper surface formed flat, the inner end of the upper surface is located inwardly to the outer end of the substrate held in the holding rotating part, and the outer end of the upper surface is located outwardly to the outer end of the hole of the liquid receiving part. Claim 5 A substrate processing apparatus according to claim 1, further comprising an airflow forming unit that forms a downward airflow of clean gas. Claim 6 A substrate processing device according to claim 5, wherein the inner diameter of the annular member is 140 mm or more and 260 mm or less. Claim 7 A substrate processing apparatus according to claim 1, wherein a labyrinth structure is formed on the upper surface of the liquid receiving portion and on the surface opposite to the upper surface of the annular member installed on the upper surface. Claim 8 A substrate processing device according to claim 1, wherein the liquid receiving portion has a seal portion that seals the space between the outer circumference of the annular member and the liquid receiving portion. Claim 9 A substrate processing device according to claim 1, comprising a suction part that sucks gas in the gap between the annular member and the liquid receiving part. Claim 10 A substrate processing apparatus according to claim 1, wherein the rotational speed of the substrate during the drying process is lower than the rotational speed of the substrate during the supply process. Claim 11 A substrate processing method using a substrate processing device, wherein the substrate processing device comprises a holding rotating part for holding and rotating a substrate, a supply part for supplying a film-forming treatment liquid to a substrate held by the holding rotating part, and a liquid receiving part for receiving the film-forming treatment liquid shaken off from the substrate by rotation by the holding rotating part, wherein the liquid receiving part further comprises an annular member configured to be retractable with respect to the upper surface of the liquid receiving part, having a hole at the top through which the substrate held by the holding rotating part passes and which becomes an opening for an upper space, wherein the surface of the annular member facing the substrate held by the holding rotating part is an inclined surface inclined such that it gradually slopes downward from the outer circumference towards the inner circumference end, and a process of supplying a film-forming treatment liquid to the substrate and rotating the substrate while exhausting the interior of the liquid receiving part while the annular member is installed on the upper surface of the liquid receiving part to block the circumference edge of the hole, and subsequently, with the annular member retracted from the upper surface of the liquid receiving part, the interior of the liquid receiving part A substrate treatment method comprising a process of drying a film-forming solution on a substrate by rotating the substrate while exhausting. Claim 12 A readable computer storage medium storing a program that operates on a computer of a control unit controlling a substrate processing device to execute the substrate processing method described in claim 11 by the substrate processing device. Claim 13 delete Claim 14 delete

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