Substrate processing apparatus and substrate processing method

Abstract

To process a substrate well in a substrate processing technique in which the substrate is processed by process liquid supplied to a periphery of the rotating substrate.SOLUTION: This invention has a guard section having an inner circumference surface surrounding an outer circumference of a rotating substrate, and a liquid film forming mechanism that forms a liquid film of absorbing liquid to absorb droplets in a collection area of the inner circumference surface that collects droplets of processing liquid that are shaken off from the rotating substrate. As a result, droplets of the processing liquid that are shaken off from the rotating substrate are collected by the liquid film in the collection area, and generation of bouncing droplets is greatly suppressed.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method for processing a peripheral portion of a substrate with a processing liquid. Here, the substrate includes a semiconductor wafer, a glass substrate for a liquid crystal display device, a glass substrate for a plasma display, a substrate for an optical disk, a substrate for a magnetic disk, a substrate for a magneto-optical disk, a glass substrate for a photomask, a substrate for a solar cell, etc. (hereinafter simply referred to as "substrate"). Further, the processing includes etching processing.

Background Art

[0002] As a substrate processing apparatus for supplying a processing liquid to a peripheral portion of a substrate while rotating the substrate such as a semiconductor wafer and performing chemical treatment, cleaning treatment, etc., for example, the apparatus described in Patent Document 1 is known. In this substrate processing apparatus, in order to receive the processing liquid scattered from the rotated substrate, a scattering prevention portion (corresponding to the "guard portion" of the present invention) is provided. The scattering prevention portion has a splash guard (sometimes referred to as a "cup") arranged so as to surround the outer periphery of the rotated substrate. The inner peripheral surface of the splash guard faces the outer periphery of the substrate and collects the droplets of the processing liquid shaken off from the rotated substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Incidentally, when droplets are collected by the splash guard, the droplets collide with the inner surface of the splash guard. This collision can cause splash droplets to bounce back. If these splash droplets re-adhere to the substrate, watermarks will occur. Furthermore, the scattering of splash droplets outside the splash guard becomes one of the main causes of contamination of the surrounding atmosphere. Therefore, in order to properly process substrates in the above-mentioned substrate processing apparatus, it is important to suppress the scattering of splash droplets.

[0005] This invention has been made in view of the above problems, and aims to improve the quality of substrate processing in a substrate processing technology that processes a substrate by supplying a processing liquid to the peripheral edge of a rotating substrate. [Means for solving the problem]

[0006] This invention 1 The embodiment is a substrate processing apparatus that processes the entire peripheral edge with a processing liquid by discharging a processing liquid from a processing liquid nozzle toward a processing start position while rotating the substrate so that the peripheral edge of the substrate passes through the processing start position along its entire circumference, comprising: a guard portion having an inner surface surrounding the outer circumference of the rotating substrate; and a liquid film forming mechanism that forms a liquid film of an absorbent liquid for absorbing liquid droplets in a collection region of the inner surface that collects liquid droplets of the processing liquid that have been shaken off the rotating substrate. The collision coefficient K when a droplet of the processing liquid collides with the liquid film is

number

[0007] Furthermore, this invention ThirdAn aspect is a substrate processing method, in which, with the outer periphery of the substrate surrounded by the inner peripheral surface of the guard portion, while discharging the processing liquid from the processing liquid nozzle toward the processing start position, the substrate is rotated so that the peripheral portion of the substrate passes through the processing start position over the entire circumference, thereby processing the entire peripheral portion with the processing liquid; and when droplets of the processing liquid are shaken off from the substrate due to the rotation of the substrate, a liquid film of an absorption liquid for absorbing the droplets is formed in a collection region on the inner peripheral surface that collects the droplets of the processing liquid. 、 The collision coefficient K when a droplet of the processing liquid collides with the liquid film is

Number

[0008] In the invention configured as described above, the processing liquid supplied to the substrate at the processing start position is shaken off from the substrate by the centrifugal force generated by the rotation of the substrate. At this time, the processing liquid scatters toward the collection region of the guard portion in a droplet state. Here, if the droplets directly collide with the collection region, splashing droplets may be generated. However, in the present invention, since a liquid film is formed in the collection region, the droplets are absorbed by the liquid film. Therefore, the generation of splashing droplets is significantly suppressed.

Effect of the Invention

[0009] As described above, according to the present invention, when droplets of the processing liquid shaken off from the rotating substrate are collected on the inner peripheral surface of the guard portion, the scattering of splashing droplets is suppressed. Therefore, reattachment of the splashing droplets to the substrate and scattering outside the guard portion are prevented. As a result, the substrate can be processed well.

Brief Description of the Drawings

[0010] [Figure 1] It is a diagram showing a substrate processing system equipped with a first embodiment of a substrate processing apparatus according to the present invention. [Figure 2] It is a diagram schematically showing the configuration of a first embodiment of a substrate processing apparatus. [Figure 3] It is a plan view of a part of the substrate processing apparatus seen from above. [Figure 4] It is a diagram showing the configuration of a liquid film forming mechanism and a splash guard part equipped in the substrate processing apparatus according to the present invention. [Figure 5] It is a plan view showing the configuration of a liquid film forming mechanism and a splash guard part equipped in a second embodiment of the substrate processing apparatus according to the present invention. [Figure 6] It is a diagram schematically showing a part of the liquid film forming mechanism and the splash guard part shown in FIG. 5. [Figure 7] It is a plan view showing the configuration of a liquid film forming mechanism and a splash guard part equipped in a third embodiment of the substrate processing apparatus according to the present invention. [Figure 8] It is a plan view showing the configuration of a liquid film forming mechanism and a splash guard part equipped in a fourth embodiment of the substrate processing apparatus according to the present invention. [Figure 9] It is a diagram schematically showing a part of the liquid film forming mechanism and the splash guard part shown in FIG. 8. [Figure 10] It is a plan view showing the configuration of a liquid film forming mechanism and a splash guard part equipped in a fifth embodiment of the substrate processing apparatus according to the present invention.

Embodiments for Carrying Out the Invention

[0011] Figure 1 shows a substrate processing system equipped with a first embodiment of the substrate processing apparatus according to the present invention. The substrate processing system 200 comprises a substrate processing unit 210 that processes substrates S, and an indexer unit 220 coupled to the substrate processing unit 210. The indexer unit 220 comprises a container holding unit 221 that can hold multiple containers C for housing substrates S (such as a FOUP (Front Opening UnifiedPod), SMIF (Standard Mechanical Interface) pod, or OC (Open Cassette) that house multiple substrates S in a sealed state), and an indexer robot 222 for accessing the containers C held by the container holding unit 221 to remove unprocessed substrates S from the containers C or to store processed substrates S in the containers C. Each container C houses multiple substrates S in a nearly horizontal position.

[0012] The indexer robot 222 comprises a base portion 222a fixed to the device housing, a multi-joint arm 222b rotatably mounted on the base portion 222a around a vertical axis, and a hand 222c attached to the tip of the multi-joint arm 222b. The hand 222c is structured to hold a substrate S placed on its upper surface. Since indexer robots having such a multi-joint arm and a hand for holding a substrate are well known, a detailed explanation will be omitted.

[0013] The substrate processing unit 210 comprises a substrate transport robot 211 positioned approximately in the center in a plan view, and a plurality of processing units 1 arranged to surround the substrate transport robot 211. Specifically, the plurality of processing units 1 are arranged facing the space in which the substrate transport robot 211 is positioned. The substrate transport robot 211 randomly accesses these processing units 1 to receive the substrate S. Meanwhile, each processing unit 1 performs predetermined processing on the substrate S. In this embodiment, one of these processing units 1 corresponds to the substrate processing apparatus 10 according to the present invention.

[0014] Figure 2 is a schematic diagram showing the configuration of the first embodiment of the substrate processing apparatus, and Figure 3 is a plan view of a part of the substrate processing apparatus viewed from above. The substrate processing apparatus 10 supplies a processing liquid to the peripheral edge of the upper surface of the substrate S in a processing chamber and performs bevel etching as an example of the "processing" of the present invention. For this purpose, the substrate processing apparatus 10 is equipped with a substrate holding unit 11, a splash guard unit 12, a processing liquid supply unit 13, and a liquid film formation mechanism 14. These operations are controlled by a control unit 90.

[0015] The substrate holder 11 is equipped with a spin chuck 111, which is a disc-shaped member smaller than the substrate S. The spin chuck 111 is supported by a rotating support shaft 113 extending downward from the center of its lower surface, so that its upper surface is horizontal. The rotating support shaft 113 is rotatably supported by a rotating mechanism 114 attached to the bottom of the processing chamber. The rotating mechanism 114 has a built-in rotary motor (not shown), and when the rotary motor rotates in response to a control command from the control unit 90, the spin chuck 111 rotates around the vertical axis shown by the dashed line. In Figure 2, the up and down direction is the vertical direction. As a result, the substrate S is rotated around the vertical axis while remaining in a horizontal position.

[0016] A splash guard portion 12 is provided as an example of the "guard portion" of the present invention, surrounding the substrate holding portion 11 from the side. The splash guard portion 12 has a generally cylindrical cup 121 provided to cover the peripheral edge of the spin chuck 111, and a liquid receiving portion 122 provided below the outer circumference of the cup 121. The cup 121 moves up and down in response to control commands from the control unit 90. When the cup 121 is positioned in the lower position, as shown in Figure 2, the upper end of the cup 121 is positioned below the peripheral edge of the substrate S held by the spin chuck 111. Conversely, when the cup 121 is positioned in the upper position, the upper end of the cup 121 is positioned above the peripheral edge of the substrate S.

[0017] When the cup 121 is in the lower position, as shown in Figure 2, the substrate S held by the spin chuck 111 is exposed to the outside of the cup 121. This prevents the cup 121 from becoming an obstacle when, for example, loading or unloading the substrate S into or out of the spin chuck 111.

[0018] On the other hand, when the cup 121 is in the upper position, the inner surface of the cup 121 surrounds the outer circumference of the substrate S held by the spin chuck 111. This prevents droplets of the processing liquid that are shaken off from the periphery of the substrate S during the bevel etching process, which will be described later, from scattering into the chamber 100. It also ensures that the processing liquid is reliably collected. Specifically, as the substrate S rotates, droplets of the processing liquid that are shaken off from the periphery of the substrate S adhere to the inner surface of the cup 121 and flow downward, where they are collected by the liquid receiving section 122 located below the cup 121. In this embodiment, a liquid film forming mechanism 14 is provided to prevent droplets from bouncing back when they collide with the inner surface of the cup 121. This will be described in detail later.

[0019] The processing liquid supply unit 13 includes a base 131, a pivot shaft 132, an arm 133, and a processing liquid nozzle 134. The base 131 is fixed to the processing chamber 100. The pivot shaft 132 is rotatably mounted on the base 131. An arm 133 extends horizontally from the pivot shaft 132, and the processing liquid nozzle 134 is attached to its tip. As the pivot shaft 132 rotates in response to a control command from the control unit 90, the arm 133 swings, and the processing liquid nozzle 134 at the tip of the arm 133 moves between a retracted position, which is moved laterally from above the substrate S as shown in Figures 2 and 3, and a processing position, which is above the peripheral edge of the substrate S as shown in Figure 3.

[0020] The processing liquid nozzle 134 is connected to a processing liquid supply unit (not shown) provided in the control unit 90. Therefore, when an appropriate amount of processing liquid is supplied from the processing liquid supply unit to the processing liquid nozzle 134 positioned at the processing position, the processing liquid is discharged from the processing liquid nozzle 134 toward the processing start position Ps. This processing start position Ps is a point on the path along which the peripheral edge of the substrate S moves. Consequently, as the spin chuck 111 rotates while the processing liquid nozzle 134 discharges the processing liquid, each part of the peripheral edge of the substrate S receives the processing liquid as it passes through the processing start position Ps. As a result, bevel etching is performed on the entire peripheral edge of the substrate S using the processing liquid.

[0021] When we examine the scattering of the processing liquid supplied to the periphery of the substrate S at the processing start position Ps, the following points become clear. That is, when the processing liquid is supplied to the periphery of the substrate S at the processing start position Ps, a portion of it is spun off the substrate S at the processing start position Ps by the centrifugal force accompanying the rotation of the substrate S. The remaining processing liquid is also spun off the substrate S by centrifugal force. However, the spun-off ends at a position Pe (hereinafter referred to as the "processing end position") which is advanced by a predetermined angle θ in the rotational direction AR1 of the substrate S from the processing start position Ps. In other words, between the processing start position Ps and the processing end position Pe, the processing liquid is gradually spun off the substrate S. At this time, the droplets of the spun-off processing liquid scatter in the tangential direction of the rotational trajectory, as shown by the dotted line in Figure 3. This "rotational trajectory" refers to the rotational trajectory traced by the outer circumference of the substrate S during its rotation.

[0022] The range over which the processing liquid supplied at the processing start position Ps continues to adhere to the peripheral edge of the substrate S (the area hatched in Figure 3), i.e., the angle θ, varies depending on the rotation speed of the substrate S and the type of processing liquid, but is less than 360°, and in general substrate processing, 0° < θ < 60°. Therefore, the collection region 123, in which the excess processing liquid droplets are collected on the inner surface of the cup 121, is limited to a part of the inner surface. More specifically, as shown in Figure 3, the collection region 123 is the range from the collection start position 123s to the collection end position 123e in the rotation direction AR1 of the substrate S. The "collection start position 123s" refers to the position where the tangent Ts of the rotation trajectory at the processing start position Ps intersects with the inner surface of the cup 121, and the "collection end position 123e" refers to the position where the tangent Te of the rotation trajectory at the processing end position Pe intersects with the inner surface. Furthermore, in the same figure, dots are added to the collection area 123 to make it clearer.

[0023] In conventional technology, droplets of the processing liquid directly collide with the inner surface of the cup 121 in the collection area 123. This can cause rebound droplets to form. Furthermore, the cup 121 is often made of a chemical-resistant material, considering that it is used as one of the processing liquids for bevel etching. From this perspective, the cup 121 is often made of hydrophobic resin, which makes it prone to rebound droplet formation. In other words, in a hydrophobic resin cup 121, droplets adhering to the inner surface do not form a liquid film but exist as granules. When droplets of the processing liquid collide with these granules, rebound is even more likely to occur than when they collide with the inner surface.

[0024] Therefore, in this embodiment, a liquid film formation mechanism 14 is provided to resolve these problems. The configuration and operation of the liquid film formation mechanism 14 will be described in detail below with reference to Figures 2 to 4.

[0025] Figure 4 shows the configuration of the liquid film forming mechanism and splash guard section equipped in the substrate processing apparatus according to the present invention. As shown in Figure 2, the liquid film forming mechanism 14 has a base 141, a pivot shaft 142, an arm 143, a scanning unit 144, and an absorbent liquid nozzle 145. The base 141 is fixed to the processing chamber 100. The pivot shaft 142 is rotatably mounted on the base 141. The arm 143 extends horizontally from the pivot shaft 142. The scanning unit 144 is mounted on the tip of the arm 143 so as to be able to reciprocate horizontally. The absorbent liquid nozzle 145 is attached below the scanning unit 144. The arm 143 swings when the pivot shaft 142 rotates in response to a control command from the control unit 90. This arm oscillation causes the scanning unit 144 and the absorbent liquid nozzle 145 at the tip of the arm 143 to move between a retracted position outside the cup 121 and a liquid film-forming space inside the cup 121, as shown in Figure 3.

[0026] The scanning unit 144, having been moved to the liquid film forming space, supports the absorbent liquid nozzle 145 with its spot-shaped discharge port 145a facing the inner circumferential surface of the cup 121. The opening width of this discharge port 145a is sufficiently smaller than that of the collection area 123, and as will be described later, the supply range of the absorbent liquid discharged from the discharge port 145a is narrower than that of the collection area 123. Therefore, in this embodiment, the scanning unit 144 is configured as follows.

[0027] As shown in Figure 3, the scanning unit 144 is capable of horizontal movement parallel to a virtual line connecting the collection start position 123s and the collection end position 123e. As shown in Figure 4, the scanning unit 144 is connected to the nozzle drive unit 146, and the absorbent liquid nozzle 145 is connected to the absorbent liquid supply unit 147. Therefore, when absorbent liquid is supplied from the absorbent liquid supply unit 147 to the absorbent liquid nozzle 145 located in the liquid film formation space, the absorbent liquid is discharged from the discharge port 145a of the absorbent liquid nozzle 145 toward the inner circumferential surface of the cup 121. In addition, the nozzle drive unit 146 moves the scanning unit 144 horizontally in response to a control command from the control unit 90. As a result, the position of the absorbent liquid supplied to the inner circumferential surface of the cup 121 changes continuously along the rotation direction AR1. Consequently, a liquid film of absorbent liquid is formed on the inner circumferential surface of the cup 121. This absorbent liquid is a liquid for absorbing droplets of processing liquid that have been shaken off the substrate S.

[0028] In this embodiment, the scanning range of the scanning unit 144 is set to correspond to the collection area 123. That is, as shown in Figure 4, when the scanning unit 144 moves integrally with the absorbent liquid nozzle 145 to one end of the collection area 123 in the rotational direction AR1, the discharge port 145a faces the collection start position 123s. Conversely, when the scanning unit 144 moves to the other end of the collection area 123, the discharge port 145a faces the collection end position 123e. In this way, the nozzle drive unit 146 has the function of moving the absorbent liquid nozzle 145 so that the discharge destination of the absorbent liquid from the discharge port 145a is scanned between the collection start position 123s and the collection end position 123e while the discharge port 145a faces the collection area 123. Then, in parallel with the scanning of the absorbent liquid nozzle 145 in this way, the absorbent liquid supply unit 147 supplies the absorbent liquid, so that the absorbent liquid is continuously supplied to the collection area 123. The absorbent liquid then flows downward along the inner surface of the cup 121, forming a liquid film LF of the absorbent liquid in the collection region 123, as shown in Figure 4.

[0029] In the substrate processing apparatus 10 described above, the formation of the liquid film LF is performed while the substrate S is being bevel-etched with the processing liquid. Therefore, droplets of the processing liquid that are shaken off from the substrate S during the bevel-etching process scatter toward a part of the inner surface of the cup 121, i.e., toward the collection area 123, but the target of these droplets is not the inner surface of the cup 121, but the liquid film LF of the absorbent liquid. Thus, according to this embodiment, the bounce-back of droplets from the cup 121 can be effectively suppressed. As a result, the bevel-etching process on the substrate S can be performed more effectively than with conventional apparatuses.

[0030] The absorbent liquid described above has the function of absorbing droplets of the processing liquid, but by appropriately selecting the type of absorbent liquid, the amount of bounced droplets can be further reduced. The reason for this is explained below. Various studies have been conducted on the collision coefficient K when droplets collide with the liquid film LF. The collision coefficient K is given by the following equation

number

[0031] For example, as pointed out in Tomio Okawa, Takuya Shiraishi, Toshiaki Mori, "Production of secondary drops during the single water drop impact onto a plane water surface," Experiments in Fluids, (2006) 41:965-974, if the collision coefficient K is 2100 or higher, it is difficult to suppress rebound droplets even if a liquid film LF is formed. Conversely, by keeping the collision coefficient K below 2100, the generation of rebound droplets can be prevented, and bevel etching can be performed with excellent quality. However, the droplet velocity Vn changes depending on the rotation speed of the substrate S during bevel etching. Therefore, it is preferable to appropriately adjust the viscosity μ of the absorbent solution so that the collision coefficient K is less than 2100, depending on the rotation speed during bevel etching. Considering this point, a mixture of pure water such as DIW with a thickener or a phosphoric acid solution can be used as the absorbent solution. Ethylene glycol, propylene glycol, polyethylene glycol, etc. can be used as thickeners. Furthermore, any glycol-based chemical solution may be poly or monomer. For example, if the rotation speed of the substrate S is set to 1800 rpm, splashing of droplets from cup 121 can be prevented by using an absorbent solution with a viscosity of 0.005 to 0.03 Pa·s.

[0032] As described above, in the first embodiment, an absorbent liquid film LF for absorbing droplets of the processing liquid is formed in the collection region 123. Therefore, droplets that are shaken off the substrate S during the bevel etching process are absorbed by the liquid film LF. Consequently, the generation of bounced droplets is significantly suppressed. Furthermore, by adjusting the density ρ of the absorbent liquid, the collision coefficient K is kept below 2100, which more reliably prevents droplets from bouncing back in the collection region 123. As a result, re-adhesion of bounced droplets to the substrate S and scattering outside the splash guard portion 12 are prevented, and the substrate S can be processed well.

[0033] Furthermore, in the first embodiment, the liquid film LF is formed only in the collection region 123. Therefore, the amount of absorbent liquid used can be minimized, and an increase in running costs can be prevented.

[0034] Figure 5 is a plan view showing the configuration of the liquid film forming mechanism and splash guard section equipped in the second embodiment of the substrate processing apparatus according to the present invention. Figure 6 is a schematic diagram showing a part of the liquid film forming mechanism and splash guard section shown in Figure 5. The main difference between this second embodiment and the first embodiment is the configuration of the splash guard section 12. More specifically, in the second embodiment, the cup 121 is composed of a cup component 121a with a cutout in the portion corresponding to the collection area 123, and a cup component 121b arranged to cover the cutout portion of the cup component 121a from the radially outer side of the cup 121. These cup components 121a and 121b move up and down together in response to control commands from the control unit 90.

[0035] The upper end of the cup component 121a is finished as a sloping portion with a canopy shape that bends inward into the cup 121. In contrast, the cup component 121b has a wall shape that extends straight vertically overall. During the bevel etching process, droplets of the processing liquid that are shaken off from the substrate S pass through the notch portion of the cup component 121a and scatter onto the inner surface of the cup component 121b. In other words, the inner surface of the cup component 121b functions as a collection area 123. Therefore, in the second embodiment as well, a liquid film forming mechanism 14 is provided to form a liquid film LF of the absorbent liquid in the collection area 123. The configuration and operation of the liquid film forming mechanism 14 are the same as those in the first embodiment.

[0036] As described above, in the second embodiment, as in the first embodiment, an absorbent liquid with a collision coefficient K of less than 2100 is supplied to the collection region 123 to form a liquid film LF of the absorbent liquid. As a result, droplets that are shaken off the substrate S during the bevel etching process are reliably absorbed by the liquid film LF. Consequently, re-adhesion of bounced droplets to the substrate S and scattering outside the splash guard portion 12 are prevented, and the substrate can be processed effectively.

[0037] In the second embodiment, the cup component 121b has a curved shape when viewed from a vertically upward plane, and when combined with the cup component 121a, it completely closes the notched portion. However, the cup component that can be combined with the cup component 121a having a notched portion is not limited to this. For example, as shown in Figure 7, a cup component 121c that is refracted when viewed from a vertically upward plane may be used (third embodiment).

[0038] Figure 7 is a plan view showing the configuration of the liquid film formation mechanism and splash guard section equipped in the third embodiment of the substrate processing apparatus according to the present invention. The main differences between this third embodiment and the second embodiment are, as described above, the structure of the cup component 121c that covers the notched portion of the cup component 121a, and the structure and operation of the absorbent liquid nozzle. The other configurations are basically the same as those of the second embodiment.

[0039] In the third embodiment, the cup component 121c has a straight wall portion that is large enough to cover the notched portion of the cup component 121a from the radially outside of the cup 121, and a support portion that bends and extends from the straight wall portion. The cup drive unit 124 is connected to this support portion. In response to a control command from the control unit 90, the cup drive unit 124 rotates the cup component 121c around the support portion of the cup component 121c. As a result, as shown in Figure 7, the inner circumferential surface of the straight wall portion of the cup component 121c (the surface facing the notched portion) moves between a collection position that covers the notched portion of the cup component 121a and a retracted position that is radially outside of the cup component 121a. When the bevel etching process is performed with the cup component 121c in the collection position, droplets of the processing liquid that have been shaken off from the substrate S pass through the notched portion of the cup component 121a and are scattered onto the straight wall portion of the cup component 121c. In other words, the inner circumferential surface of the straight wall portion of the cup component 121c functions as a collection area 123.

[0040] In the third embodiment, an absorbent liquid nozzle 148 is used to discharge the absorbent liquid toward the collection region 123. This absorbent liquid nozzle 148 has a slit-shaped discharge port 148a that extends parallel to a virtual line connecting the collection start position 123s and the collection end position 123e. Although not shown in Figure 7, this absorbent liquid nozzle 148 is attached to the tip of the arm 143. Therefore, when performing bevel etching, the discharge port 148a is positioned so as to face the straight wall portion of the cup component 121c located at the collection position, i.e., the collection region 123. Then, the absorbent liquid supply unit 147 supplies the absorbent liquid, and the absorbent liquid is supplied to the collection region 123 all at once from the slit-shaped discharge port 148a. As a result, a liquid film LF of the absorbent liquid is formed in the collection region 123.

[0041] As described above, the same effects and advantages as in the second embodiment can be obtained in the third embodiment as well. In the third embodiment, the cup component 121c and the absorbent liquid nozzle 148 are configured to move individually, but they may also be configured to move integrally.

[0042] In the second and third embodiments described above, cup components 121b and 121c are combined with cup component 121a, which has a notched portion and is substantially C-shaped when viewed from a vertically upward plane. The combination of cup components 121b and 121c is not limited to cup component 121a. For example, as shown in Figures 8 and 9, the present invention may be applied to a substrate processing apparatus 10 that uses a cup 121 which is a combination of cup component 121d, which has a different structure from cup component 121a, and cup component 121b (fourth embodiment). Furthermore, as shown in Figure 10, the present invention may be applied to a substrate processing apparatus 10 that uses a cup 121 which is a combination of cup component 121d and cup component 121c (fifth embodiment).

[0043] Figure 8 is a plan view showing the configuration of the liquid film forming mechanism and splash guard section equipped in the fourth embodiment of the substrate processing apparatus according to the present invention. Figure 9 is a schematic diagram showing a part of the liquid film forming mechanism and splash guard section shown in Figure 8. The cup component 121d used in the fourth embodiment has an inclined portion 121d1 formed around the entire circumference of the cup, and a notch portion 121d3 is provided in the vertical portion 121d2 that extends in the vertical direction and corresponds to the collection area 123. With respect to the cup component 121d configured in this way, the cup component 121b is positioned to cover the notch portion of the cup component 121a from the radially outside of the cup 121. The other configurations and operations are the same as in the second embodiment.

[0044] Figure 10 is a plan view showing the configuration of the liquid film forming mechanism and splash guard section equipped in the fifth embodiment of the substrate processing apparatus according to the present invention. In this fifth embodiment, the liquid film LF is formed in the same manner as in the third embodiment, with the cup component 121c positioned so that the inner circumferential surface (the surface facing the notch) of the straight wall portion of the cup component 121c covers the notch portion 121d3 of the cup component 121d, as used in the fourth embodiment.

[0045] As described above, in the fourth and fifth embodiments as well, an absorbent liquid with a collision coefficient K of less than 2100 is supplied to the collection region 123 to form a liquid film LF of the absorbent liquid, so that droplets that are shaken off the substrate S during the bevel etching process are reliably absorbed into the liquid film LF. As a result, re-adhesion of bounced droplets to the substrate S and scattering outside the splash guard portion 12 are prevented, and the substrate can be processed well.

[0046] It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be made to those described above without departing from the spirit of the invention. For example, in the first embodiment, an absorbent liquid nozzle 145 having a spot-shaped discharge port 145a is used, but an absorbent liquid nozzle having a slit-shaped discharge port may also be used, as in the third embodiment (Figure 7) and the fifth embodiment (Figure 10).

[0047] Furthermore, although the present invention is applied to a substrate processing apparatus 10 with one processing start position in the above embodiment, the present invention can also be applied to a substrate processing apparatus 10 with multiple processing start positions. For example, if two different processing start positions are provided, there are two collection regions 123. Therefore, by providing a liquid film formation mechanism 14 for each collection region 123 to form a liquid film LF of the absorbent liquid, the same effects as in the above embodiment can be obtained. [Industrial applicability]

[0048] This invention can be applied to all types of substrate processing, specifically the processing of the peripheral edges of a substrate with a processing solution. [Explanation of Symbols]

[0049] 1… Processing unit 10... Circuit board processing equipment 12... Splash guard section (guard section) 14…Liquid film formation mechanism 121...cup 121a, 121b, 121c, 121d... Cup parts 121d1…Slope part 121d2…Vertical section 121d3... Notch area 123…Collection area 123e... Collection end position 123s…Collection start position 124...Cup drive unit 144... Scanning Department 145, 148… Absorbent liquid nozzle 145a, 148a...Discharge port 146... Nozzle drive unit 147... Absorbent liquid supply unit AR1…Direction of rotation LF…Liquid film Pe... Processing end position Ps... Processing start position S... Circuit board Te, Ts... tangent lines

Claims

1. A substrate processing apparatus that processes the entire peripheral edge with the processing liquid by discharging the processing liquid from a processing liquid nozzle toward the processing start position and rotating the substrate so that the peripheral edge of the substrate passes over the entire circumference of the substrate. A guard portion having an inner surface surrounding the outer periphery of the rotating substrate, A liquid film forming mechanism is provided in a collection region of the inner circumferential surface that collects droplets of the processing liquid that have been shaken off the rotating substrate, and in which a liquid film of an absorbent liquid is formed to absorb the droplets. Equipped with, The collision coefficient K when a droplet of the processing liquid collides with the liquid film is [Math 2] however, D is the diameter of the droplet. vn is the velocity component of the droplet in the direction normal to the liquid film. ρ is the density of the droplet. μ is the viscosity of the absorbent liquid. σ is the surface tension of the droplet. So, The absorbent liquid is a liquid whose collision coefficient K is less than 2100. A substrate processing apparatus characterized by the following:

2. A substrate processing apparatus according to claim 1, If we define the processing end position as the position where the processing liquid supplied to the peripheral edge of the substrate at the processing start position is completely removed from the substrate during its rotation, and define the trajectory traced by the outer surface of the substrate due to its rotation as the rotation trajectory, then, A substrate processing apparatus in which the collection region is the range from a collection start position where the tangent to the rotation trajectory at the processing start position intersects with the inner circumferential surface in the rotation direction of the substrate, to a collection end position where the tangent to the rotation trajectory at the processing end position intersects with the inner circumferential surface.

3. A substrate processing apparatus according to claim 2, The aforementioned liquid film formation mechanism is An absorbent liquid nozzle having a discharge port narrower than the collection region in the rotational direction of the substrate, and configured to discharge the absorbent liquid from the discharge port into the collection region, An absorbent liquid supply unit that supplies the absorbent liquid to the absorbent liquid nozzle and discharges the absorbent liquid from the absorbent liquid nozzle, A nozzle drive unit moves the absorbent liquid nozzle so that the discharge point of the absorbent liquid from the discharge port is scanned between the collection start position and the collection end position, while the discharge port is facing the collection area. A substrate processing apparatus having

4. A substrate processing apparatus according to claim 1 or 2, The aforementioned liquid film formation mechanism is An absorbent liquid nozzle having a slit-shaped discharge port facing the collection region in the rotational direction of the substrate, and configured to discharge the absorbent liquid from the discharge port into the collection region, An absorbent liquid supply unit that supplies the absorbent liquid to the absorbent liquid nozzle and discharges the absorbent liquid from the absorbent liquid nozzle, A substrate processing apparatus having

5. A substrate processing apparatus according to claim 1, The aforementioned absorbent liquid is a mixture of pure water and a thickening agent, or a solution containing phosphoric acid, in a substrate processing apparatus.

6. A substrate processing apparatus that processes the entire peripheral edge with the processing liquid by discharging a processing liquid from a processing liquid nozzle toward a processing start position and rotating the substrate so that the peripheral edge of the substrate passes through the processing start position over its entire circumference, A guard portion having an inner surface surrounding the outer periphery of the rotating substrate, A liquid film forming mechanism is provided in a collection region of the inner circumferential surface that collects droplets of the processing liquid that have been shaken off the rotating substrate, and in which a liquid film of an absorbent liquid is formed to absorb the droplets. Equipped with, If we define the processing end position as the position where the processing liquid supplied to the peripheral edge of the substrate at the processing start position is completely removed from the substrate during its rotation, and define the trajectory traced by the outer surface of the substrate due to its rotation as the rotation trajectory, then, The collection region is the range from the collection start position where the tangent to the rotation trajectory at the processing start position intersects with the inner circumferential surface in the rotation direction of the substrate, to the collection end position where the tangent to the rotation trajectory at the processing end position intersects with the inner circumferential surface. The aforementioned liquid film formation mechanism is An absorbent liquid nozzle having a discharge port narrower than the collection region in the rotational direction of the substrate, and configured to discharge the absorbent liquid from the discharge port into the collection region, An absorbent liquid supply unit that supplies the absorbent liquid to the absorbent liquid nozzle and discharges the absorbent liquid from the absorbent liquid nozzle, A nozzle drive unit moves the absorbent liquid nozzle so that the discharge point of the absorbent liquid from the discharge port is scanned between the collection start position and the collection end position, while the discharge port is facing the collection area. has A substrate processing apparatus characterized by the following:

7. The process involves surrounding the outer periphery of the substrate with the inner surface of the guard portion, discharging the processing liquid from the processing liquid nozzle toward the processing start position, and rotating the substrate so that the entire peripheral edge of the substrate passes through the processing start position along its entire circumference, thereby processing the entire peripheral edge with the processing liquid. The process of forming a liquid film of an absorbent liquid to absorb the droplets when the droplets of the processing liquid are shaken off the substrate by the rotation of the substrate, in a collection region on the inner circumferential surface that collects the droplets of the processing liquid, Equipped with, The collision coefficient K when a droplet of the processing liquid collides with the liquid film is [Math 2] however, D is the diameter of the droplet. vn is the velocity component of the droplet in the direction normal to the liquid film. ρ is the density of the droplet. μ is the viscosity of the absorbent liquid. σ is the surface tension of the droplet. So, The absorbent liquid is a liquid whose collision coefficient K is less than 2100. A substrate processing method characterized by the following:

8. A step of treating the entire peripheral edge with the processing liquid by surrounding the outer periphery of the substrate with the inner surface of the guard portion, discharging the processing liquid from the processing liquid nozzle toward the processing start position, and rotating the substrate so that the peripheral edge of the substrate passes through the processing start position along its entire circumference, The process of forming a liquid film of an absorbent liquid to absorb the droplets when the droplets of the processing liquid are shaken off the substrate by the rotation of the substrate, in a collection region on the inner circumferential surface that collects the droplets of the processing liquid, Equipped with, If we define the processing end position as the position where the processing liquid supplied to the peripheral edge of the substrate at the processing start position is completely removed from the substrate during its rotation, and define the trajectory traced by the outer surface of the substrate due to its rotation as the rotation trajectory, then, The collection region is the range from the collection start position where the tangent to the rotation trajectory at the processing start position intersects with the inner circumferential surface in the rotation direction of the substrate, to the collection end position where the tangent to the rotation trajectory at the processing end position intersects with the inner circumferential surface. The step of forming the liquid film is, A step of supplying the absorbent liquid to an absorbent liquid nozzle having a discharge port narrower than the collection area in the rotational direction of the substrate, and discharging the absorbent liquid from the discharge port into the collection area, A step of moving the absorbent liquid nozzle so that the discharge point of the absorbent liquid from the discharge port is scanned between the collection start position and the collection end position, while the discharge port is facing the collection area. including A substrate processing method characterized by the following:

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