CN117650075A - Substrate cleaning device - Google Patents

Abstract

The invention provides a substrate cleaning device, which can prevent a polished substrate from being cleaned in a cleaning part under the state of insufficient hydrophilization. The substrate cleaning device of the embodiment comprises: a chamber into which a substrate having a polishing surface polished by a polishing device is carried; a support portion disposed in the chamber and supporting the substrate; a supply unit configured to supply a cleaning liquid for hydrophilizing the polishing surface to the polishing surface of the substrate supported by the support unit; an imaging unit that images a polished surface to which a cleaning liquid is supplied from a side surface of a substrate; a determination unit that determines whether or not hydrophilization is possible based on the image captured by the imaging unit; an adjusting unit configured to adjust the supply of the cleaning liquid by the supplying unit, based on the determination result by the determining unit; and a cleaning unit connected to the chamber, for cleaning the polishing surface hydrophilized by the cleaning liquid.

Description

Substrate cleaning device

Technical Field

The present invention relates to a substrate cleaning apparatus.

Background

In a manufacturing process of a semiconductor device, there is a case where a surface of a wafer of a semiconductor serving as a substrate is required to be cleaned with high cleanliness. For example, chemical mechanical polishing (CMP: chemical Mechanical Polishing) is performed to planarize the surface of the substrate. Then, after polishing, particles (hereinafter, referred to as contaminants) adhere to the surface of the substrate. The contaminants are organic matter, grinding dust containing metal, residue dust of slurry, and the like.

Such contaminants may interfere with the planar film formation or cause short circuits of the circuit pattern, and thus if the contaminants remain, product defects may be caused. Therefore, it is necessary to remove the substrate by cleaning the substrate with a cleaning liquid. As a device for performing such cleaning, a cleaning device using a rotating brush is known (see patent document 1).

The cleaning device is provided with a brush cleaning device and a rotary cleaning device. The brush cleaning device cleans a substrate with a rotating brush and a cleaning liquid. That is, when the cleaning liquid is supplied to the surface of the rotating substrate, the rotating brush is brought into contact with the surface of the rotating substrate, and the brush is moved in a direction parallel to the substrate. Contaminants adhering to the surface of the substrate are floated by the cleaning liquid and discharged to the outside of the substrate by the brush. Thus, the substrate as a whole is cleaned. The spin cleaning apparatus supplies a cleaning liquid to a substrate to be spun, and dries the substrate by blowing a gas.

[ Prior Art literature ]

[ patent literature ]

[ patent document 1] Japanese patent laid-open publication No. 2003-077877

Disclosure of Invention

[ problem to be solved by the invention ]

If the polished substrate is dried, the polishing agent is fixed, and removal is difficult. Therefore, in the above-described substrate cleaning apparatus, ozone water or the like is discharged for a predetermined period of time in the receiving chamber connected to the polishing apparatus, thereby hydrophilizing the substrate. Thereafter, the cleaning solution is conveyed to a brush cleaning device to perform brush cleaning.

However, since the polished surface of the substrate is water repellent, hydrophilization may be insufficient. In this way, even when brush cleaning is performed in a state where hydrophilization is insufficient, the abrasive fixed by drying is generated, and removal is difficult.

An object of an embodiment of the present invention is to provide a substrate cleaning apparatus capable of preventing a polished substrate from being cleaned in a cleaning section in a state where hydrophilization is insufficient.

[ means for solving the problems ]

In order to solve the above problems, a substrate cleaning apparatus according to the present invention includes: a chamber into which a substrate having a polishing surface polished by a polishing device is carried; a support unit which is provided in the chamber and supports the substrate; a supply unit configured to supply a cleaning liquid for hydrophilizing the polishing surface to the polishing surface of the substrate supported by the support unit; an imaging unit that photographs the polished surface to which the cleaning liquid is supplied from the side surface of the substrate; a determination unit configured to determine whether or not hydrophilization is possible based on the image captured by the imaging unit; an adjusting unit configured to adjust the supply of the cleaning liquid by the supplying unit, based on a determination result by the determining unit; and a cleaning unit connected to the chamber and configured to clean the polishing surface hydrophilized by the cleaning liquid.

[ Effect of the invention ]

The invention provides a substrate cleaning device capable of preventing a polished substrate from being cleaned in a cleaning part under a state of insufficient hydrophilization.

Drawings

Fig. 1 is a schematic plan view showing a schematic configuration of a substrate cleaning apparatus and a polishing apparatus according to an embodiment.

Fig. 2 is a side view showing a schematic configuration of the substrate cleaning apparatus and the polishing apparatus according to the embodiment.

Fig. 3 (a) is a plan view showing a state in which the nozzle of the supply unit ejects the cleaning liquid onto the substrate, and fig. 3 (B) is a plan view showing a state in which the image pickup unit picks up an image from the side surface of the substrate.

Fig. 4 (a) is an explanatory view showing an image serving as a reference in a state where hydrophilization is performed, fig. 4 (B) is an explanatory view showing an image of a substrate where hydrophilization is sufficiently performed, fig. 4 (C) is an explanatory view showing an image of a substrate where hydrophilization is insufficient, fig. 4 (D) is an explanatory view showing an image in which the image of fig. 4 (a) is superimposed on the image of fig. 4 (B), and fig. 4 (E) is an explanatory view showing an image in which the image of fig. 4 (a) is superimposed on the image of fig. 4 (C).

Fig. 5 is a flowchart showing a processing procedure of the substrate cleaning apparatus.

[ description of reference numerals ]

1: substrate cleaning device

31: mechanism control part

32: image pickup control unit

33: determination unit

34: adjusting part

100: hydrophilizing part

110. 211, 221, C: chamber chamber

111：FFU

111a, 111b: an opening

112a, 112b: baffle plate

120: support part

121: supporting pin

121a: conical surface

130: supply part

131. 214a, 223a: nozzle

140: image pickup unit

141: camera with camera body

150: conveying part

151. 231: mechanical arm

200: cleaning part

210: brush cleaning device

212: rotation driving part

212a, R: roller

213: brush driving part

213a: brush with brush body

214. 223, 223: liquid supply part

220: rotary cleaning device

222: rotation driving part

222a: pin

222b: rotary workbench

223b: swing arm

230: conveying device

232: moving mechanism

300: control unit

d: distance of

L: cleaning liquid

P: grinding device

S: polishing pad

S01, S02, S03, S04, S05, S06, S07, S08, S09, S10, S11, S12: step (a)

W: substrate board

Detailed Description

Summary

Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in fig. 1, the present embodiment relates to a substrate cleaning apparatus 1 for cleaning a substrate W polished by a polishing apparatus P. The substrate cleaning apparatus 1 includes a hydrophilization section 100, a cleaning section 200, and a control section 300. The hydrophilization portion 100 performs hydrophilization by supplying a cleaning liquid L to the polished surface of the polished substrate W. The cleaning section 200 performs brush cleaning and spin cleaning on the polished surface of the hydrophilized substrate W. The control unit 300 controls the operations of the hydrophilization unit 100 and the washing unit 200.

The polishing apparatus P is an apparatus for polishing the front and back surfaces of the substrate W. The polishing apparatus P of the present embodiment is an apparatus for performing CMP (chemical mechanical polishing: chemical Mechanical Polishing). Fig. 2 shows a schematic structure of the polishing apparatus P. In the polishing apparatus P, the rotating roller R holds the outer periphery of the substrate W and rotates the substrate W in the chamber C. Therefore, the polishing pad S is rotated while supplying a cleaning liquid L described later to the front and rear surfaces of the substrate W, and is brought into contact with the substrate W to polish the substrate W.

The substrate W to be polished and cleaned is typically a circular semiconductor wafer. The substrate W may be a substrate for a display device. The surface of the substrate W polished by the polishing device P is a polishing surface. In the present embodiment, the polishing surfaces are the front surface and the back surface of the substrate W. In the following description, the polishing surfaces on the front and rear surfaces may be referred to as only two surfaces.

Structure

(hydrophilization section)

The hydrophilization section 100 includes a chamber 110, a support section 120, a supply section 130, an imaging section 140, and a conveyance section 150. The chamber 110 is a container into which a substrate W having a polishing surface polished by the polishing apparatus P is carried. The chamber 110 is provided with an opening 111a and an opening 111b for carrying the substrate W in and out between the polishing apparatus P and the cleaning section 200. The openings 111a and 111b can be opened and closed by the shutters 112a and 112 b. The shutters 112a and 112b open the openings 111a and 111b when the substrate W is carried in and carried out. During the hydrophilization treatment, the shutter 112a and the shutter 112b close the openings 111a and 111b.

As shown in fig. 2, a Fan Filter Unit (FFU) 111 is provided at an upper portion of the chamber 110. The FFU 111 is a blower that has a fan and a high efficiency molecular air (High efficiency particulate air, HEPA) filter, not shown, and that sends cleaned air into the chamber 110. An undershoot flow from the top of the chamber 110 toward the ground is generated by the FFU 111. By the undershoot flow, dust flies and does not adhere to the substrate W. An exhaust port, not shown, is provided on the floor of the chamber 110.

As shown in fig. 2, the support 120 is provided in the chamber 110, and supports the substrate W carried into the chamber 110. The support 120 supports the substrate W in a horizontal state so that both surfaces of the substrate W are exposed. The support portion 120 of the present embodiment has 4 support pins 121 that are columnar in the vertical direction. The support pins 121 are installed in the chamber 110 at equal intervals along the periphery of the substrate W. An inclined tapered surface 121a is formed at the upper end of the support pin 121. The tapered surface 121a of each support pin 121 faces the center of the substrate W, and the outer periphery of the substrate W is placed thereon. Thereby, the substrate W is supported in a stationary state without rotation.

As shown in fig. 3 (a), the supply unit 130 supplies the cleaning liquid L for hydrophilizing the polishing surface of the substrate W to the polishing surface of the substrate W supported by the support unit 120. The supply unit 130 includes a plurality of nozzles 131, and discharges the cleaning liquid L from the tips of the nozzles 131 toward the polishing surface of the substrate W. The cleaning liquid L of the present embodiment is ozone water or pure water. The cleaning liquid L may be SC-1 (a liquid obtained by mixing aqueous ammonia with hydrogen peroxide water).

The nozzle 131 clamps the center of the substrate W and is provided with a pair. The nozzle 131 is provided at a position where the cleaning liquid L can be supplied to both (both) of the opposite polishing surfaces of the substrate W. That is, the substrate W is held therebetween, and a pair of nozzles 131 are disposed in the upper and lower directions. One end of each nozzle 131 is a discharge port for discharging the cleaning liquid L from an inclined direction toward the polishing surface of the substrate W. The discharge port blows out the cleaning liquid L in a fan shape in a plan view.

The pair of nozzles 131 facing each other blow the cleaning liquid L from the outside of the substrate W toward the vicinity of the center of the polishing surface to the upper polishing surface and the lower polishing surface of the substrate W. Thus, the cleaning liquid L spreads from one of the outer peripheral ends to the other outer peripheral end on both sides of the substrate W. The cleaning liquid L flows from the outer peripheral end near the nozzle 131 to the distal outer peripheral end. Therefore, in the blowing from only one direction, the cleaning liquid L is easily biased toward the far outer peripheral end. However, by blowing the cleaning liquid L from two opposite directions, the cleaning liquid L compensates for the deviation between the two directions and spreads uniformly over the entire surface.

The other end of the nozzle 131 is connected to a supply device of the cleaning liquid L, not shown, via a pipe. The supply device includes a liquid feeding device, a valve, and the like connected to an ozone water producing device (ozone water storage tank).

As shown in fig. 3 (B), the imaging unit 140 photographs the polished surface to which the cleaning liquid L is supplied from the side surface of the substrate W. The imaging from the side surface is performed so as to include the outer peripheral edge and the upper and lower liquid films in the visual field. Fig. 4 (B) and 4 (C) are examples of the image thus captured. Fig. 4 (a) to 4 (E) illustrate an example in which a part of an image of the substrate W is captured as an image up to an end portion on the opposite side of the substrate W. The imaging unit 140 includes a plurality of cameras 141. The camera 141 is disposed on the front surface of the substrate W such that the optical axis is directed toward the outer peripheral end of the substrate W. The cameras 141 of the present embodiment are arranged at equal intervals along the outer periphery of the substrate W. Thus, the imaging unit 140 can cover the entire circumference of the substrate W as an imaging range. That is, the camera 141 is disposed such that the optical axis is oriented toward the center of the substrate W supported by the support 120 in a horizontal state and parallel to the polishing surface of the substrate W supported by the support 120 in a horizontal state, and the height coincides with the center position in the thickness direction of the substrate W.

The conveying unit 150 includes a robot 151. The robot 151 holds the substrate W and conveys the substrate W carried in from the polishing apparatus P to the support 120.

(cleaning section)

As shown in fig. 1, the cleaning unit 200 includes a brush cleaning device 210, a spin cleaning device 220, and a conveyance device 230. The brush cleaning device 210 and the spin cleaning device 220 sandwich the conveyor 230, respectively, and are provided in a pair.

As shown in fig. 2, the brush cleaning device 210 includes a chamber 211, a rotation driving unit 212, a brush driving unit 213, and a liquid supply unit 214. The chamber 211 is a container in which brush cleaning of the substrate W is performed. The rotation driving unit 212 holds and rotates the outer periphery of the substrate W by a plurality of rollers 212 a.

The brush driving unit 213 brings the rotating brush 213a into contact with the polishing surface of the substrate W. The brush driving unit 213 moves the brush 213a in a direction parallel to the polishing surface of the substrate W. The brush 213a is provided with a pair of upper and lower brushes so as to hold the substrate W from above and below. The liquid supply portion 214 supplies the cleaning liquid L to the upper and lower polishing surfaces of the substrate W. The liquid supply portion 214 includes a nozzle 214a for ejecting the cleaning liquid L toward the polishing surface of the substrate W.

The brush cleaning device 210 holds the substrate W carried in by a carrying device 230 described later by a roller 212 a. The brush 213a is rotated to be in contact with both surfaces of the substrate W while supplying the cleaning liquid L to both surfaces of the substrate W rotated by the roller 212 a. The brush 213a moves in parallel on the polishing surface of the substrate W, and both surfaces of the substrate W are cleaned.

The rotary washing apparatus 220 includes a chamber 221, a rotary driving unit 222, and a liquid supply unit 223. The chamber 221 is a container in which spin cleaning of the substrate W is performed. The rotation driving part 222 holds and rotates the outer circumference of the substrate W by pins 222a contacting/separating the substrate W. The pin 222a is provided on a rotary table 222b rotated by a motor. The liquid supply portion 223 supplies the cleaning liquid L to the upper and lower polishing surfaces of the substrate W.

The liquid supply portion 223 includes a nozzle 223a for ejecting the cleaning liquid L toward the polishing surface of the substrate W. A nozzle 223a for ejecting the cleaning liquid L from the upper side of the substrate W is provided at the front end of the swing arm 223 b. Although not shown, a nozzle 223a for ejecting the cleaning liquid L from the lower side of the substrate W is provided in the spin table 222b.

The spin cleaning apparatus 220 holds the substrate W carried in by the carrier apparatus 230 by the pins 222 a. The cleaning is performed by ejecting the cleaning liquid L from the nozzle 223a onto both surfaces of the substrate W rotated by the rotation of the rotating table 222b.

The conveyor 230 includes a robot 231 and a moving mechanism 232. The robot 231 holds the substrate W. The moving mechanism 232 moves the robot 231. The transfer device 230 transfers the substrate W between the hydrophilization portion 100 and the brush cleaning device 210, and between the brush cleaning device 210 and the spin cleaning device 220. The conveyance is performed in a state where a liquid film of the cleaning liquid L is formed on the polishing surface of the substrate W. This is because the substrate W is prevented from drying on the polishing surface and contaminants adhering to the polishing surface during the conveyance of the substrate W.

(control part)

The control unit 300 is a computer that controls each unit of the substrate cleaning apparatus 1. The control unit 300 includes a processor, a memory, and a drive circuit. The control unit 300 executes a program or operation conditions stored in the memory by the processor, and drives each unit via the drive circuit. That is, the control unit 300 controls the operations of the supply unit 130, the imaging unit 140, and the conveying unit 150. The control unit 300 controls operations of the brush cleaning device 210, the spin cleaning device 220, and the conveyance device 230. The control unit 300 further includes an input device for inputting information and a display device for displaying information.

As shown in fig. 2, the control unit 300 of the present embodiment includes a mechanism control unit 31, an imaging control unit 32, a determination unit 33, and an adjustment unit 34. The mechanism control unit 31 controls the operation of the mechanism in each unit. More specifically, the mechanism control unit 31 controls the operation of the robot 151, the ejection of the cleaning liquid L from the nozzle 131, and the imaging by the imaging unit 140.

The imaging control unit 32 controls the timing of imaging by the imaging unit 140 via the mechanism control unit 31. For example, the imaging control unit 32 performs imaging by the imaging unit 140 at a predetermined timing. At the time of the photographing, the mechanism control section 31 stops the ejection of the cleaning liquid L through the nozzle 131. For example, the image pickup unit 140 picks up an image of the substrate W at a timing when the supply of the cleaning liquid L is stopped after the supply of the cleaning liquid L is stopped for about 30 seconds to 40 seconds. When hydrophilization is insufficient, the supply of the cleaning liquid L is stopped after the cleaning liquid L is supplied again for about 30 to 40 seconds, and the imaging unit 140 captures an image of the substrate W.

The determination unit 33 determines whether or not hydrophilization is possible based on the image captured by the imaging unit 140 and the image of the hydrophilized polishing surface. For example, as shown in fig. 4 (a), an image captured from the side surface of the substrate W is in a state in which a liquid film is formed so as to cover both surfaces of the substrate W. The memory stores such an image captured in advance by the imaging unit 140 as a reference image. At this time, the determining unit 33 extracts the contours of the cleaning liquid L and the substrate W. The reference image is an image obtained by photographing the substrate W hydrophilized by cleaning in an ideal state (normal). The state in which hydrophilization is normally performed is, for example, a state in which the entire polishing surface of the substrate W is covered with the cleaning liquid L. In addition, the reference image may be obtained by actual photographing, or may be generated based on a design value or a theoretical value.

As shown in fig. 4 (B), the entire surface of the substrate W is covered with the cleaning liquid L in the image of the substrate W, both surfaces of which are hydrophilized, in the actual process. On the other hand, an image with insufficient hydrophilization is as shown in fig. 4 (C). In this case, an exposed portion of the surface of the substrate W is generated. Namely, the following state is established: a state in which the region where the cleaning liquid L is not present and the polished surface is exposed is generated.

Therefore, the determination unit 33 determines whether or not hydrophilization is possible as described below. First, the determination unit 33 extracts the contours of the substrate W and the cleaning liquid L in the captured image. As shown in fig. 4 (D) and 4 (E), the determination unit 33 superimposes the captured image on the reference image. At this time, the determination unit 33 overlaps the substrate W so that the contours of the substrates coincide. In the captured image, a portion where the distance d between the contour of the cleaning liquid L and the contour of the substrate W is equal to or smaller than the first threshold value may be determined to be insufficiently hydrophilized. For example, the area indicated by the white arrow in fig. 4 (E) may be referred to as insufficient hydrophilization. The first threshold value is set to an arbitrary value within a range of 10% or less of the distance between the contour of the cleaning liquid L and the contour of the substrate W in the reference image, for example. The determination unit 33 obtains the area ratio of the portion of the captured image where hydrophilization is insufficient with respect to the area of the cleaning liquid L of the reference image. When the area ratio of the portion having insufficient hydrophilization exceeds the second threshold value, the determination unit 33 determines that hydrophilization is not possible. The second threshold value is set to an arbitrary value within a range of 10% or more of the area of the cleaning liquid L in the reference image, for example. The first threshold value and the second threshold value are input in advance through an input device and stored in a memory.

For example, in fig. 4D, there is a portion (a black portion on the side surface of the substrate W in the figure) where the distance D between the contour of the cleaning liquid L and the contour of the substrate W is smaller than the distance between the contour of the cleaning liquid L and the contour of the substrate W in the reference image. However, the distance d is not equal to or less than the first threshold, and there is no portion where hydrophilization is insufficient. Therefore, the area ratio of the portion having insufficient hydrophilization is equal to or smaller than the second threshold value, and it is determined that hydrophilization is possible.

In fig. 4 (E), since the distance d between the contour of the cleaning liquid L and the contour of the substrate W is equal to or less than the first threshold value (the portion having insufficient hydrophilization), and the area ratio of the portion having insufficient hydrophilization with respect to the area of the cleaning liquid L of the reference image is equal to or greater than the area ratio of the second threshold value, it is determined that hydrophilization is impossible.

The adjustment unit 34 adjusts the supply of the cleaning liquid L by the supply unit 130 based on the determination result by the determination unit 33. For example, when hydrophilization is not performed, the adjusting unit 34 supplies the cleaning liquid L again through the supplying unit 130. When hydrophilization is possible, the adjustment unit 34 conveys the substrate W to the cleaning unit 200 without supplying the cleaning liquid L again.

Action

The operation of the substrate cleaning apparatus 1 having the above-described configuration will be described with reference to the flowchart of fig. 5, except for fig. 1 to 4 (a) to 4 (E).

First, as shown in fig. 2, the robot 151 carries the substrate W polished on the front and back surfaces by the polishing apparatus P into the chamber 110 (step S01). The robot 151 places the substrate W on the support pins 121 of the support 120 (step S02). Thereby, the substrate W is horizontally supported.

As shown in fig. 2 and 3a, the nozzle 131 of the supply unit 130 supplies the cleaning liquid L to the front and back polishing surfaces of the substrate W (step S03). Contaminants (organic contaminants such as slurry and metal contaminants) remaining in the CMP process adhere to the polishing surface of the front and back surfaces of the substrate W. By applying ozone water to such a polished surface, an oxide film is formed and hydrophilization is performed.

After the predetermined time has elapsed (YES in step S04), the nozzle 131 stops the supply of the cleaning liquid L (step S05). Then, as shown in fig. 3B, the imaging unit 140 photographs the side surface of the substrate W (step S06). The determination unit 33 determines whether or not hydrophilization is possible based on the image captured by the imaging unit 140 and a reference image stored in advance (step S07). If it is determined that hydrophilization is not possible (NO in step S08), the nozzle 131 supplies the cleaning liquid L (step S03). Thereafter, the processing from step S04 to step S07 is performed.

When the determination unit 33 determines that hydrophilization is possible (yes in step S08), the robot 231 carries the substrate W into the cleaning unit 200 (step S09). First, the robot 231 carries the substrate W into the chamber 211. Then, the polished surface of the substrate W is brushed and cleaned in the chamber 211 (step S10). Thereby, the contaminants on the polished surface of the substrate W are discharged to the outside of the substrate W by the brush 213 a.

Next, the robot 231 carries the substrate W from the chamber 211 into the chamber 221. Then, the polished surface of the substrate W is spin-cleaned in the chamber 221 (step S11). Thereafter, the robot 231 removes the substrate W from the chamber 221 (step S12).

[ Effect ]

(1) As described above, the substrate cleaning apparatus 1 of the present embodiment includes: a chamber 110 into which a substrate W having a polishing surface polished by the polishing device P is carried; a support portion 120 disposed in the chamber 110 and supporting the substrate W; a supply unit 130 for supplying a cleaning liquid L for hydrophilizing the polishing surface to the polishing surface of the substrate W supported by the support unit 120; an imaging unit 140 that images a polishing surface to which the cleaning liquid L is supplied from the side surface of the substrate W; a determination unit 33 that determines whether or not hydrophilization is possible based on the image captured by the imaging unit 140; an adjusting unit 34 for adjusting the supply of the cleaning liquid L by the supplying unit 130 based on the determination result by the determining unit 33; and a cleaning unit 200 connected to the chamber 110, for cleaning the polishing surface hydrophilized by the cleaning liquid L.

Therefore, it is determined whether or not hydrophilization of the polished substrate W is possible, and the cleaning liquid L can be supplied to the substrate W until hydrophilization becomes sufficient (it is determined that hydrophilization is possible). This prevents the cleaning by the cleaning section 200 from being directly performed in a state where hydrophilization of the polished substrate W is insufficient. Therefore, the cleaning part 200 can easily remove contaminants from the substrate W.

Further, since the imaging unit 140 performs imaging from the side surface of the substrate W, the imaging unit 140 does not need to be provided directly above the substrate W. Therefore, the cleaning liquid L attached to the image pickup unit 140 drops and adheres to the substrate W, and the substrate W is prevented from being contaminated. Further, since the imaging unit 140 is not present on the substrate W, the undershoot flow is not impeded.

Further, by imaging the side surface of the substrate W by the imaging unit 140, the state of both the opposite polished surfaces of the substrate W can be imaged. Therefore, it is possible to determine whether or not hydrophilization can be performed on the back surface side which cannot be determined in the photographing from directly above the substrate W. In addition, it takes time to inspect when photographing both sides by turning the substrate W over or the like. In the present embodiment, the imaging unit 140 can take images of both surfaces of the substrate W from the side surface thereof at the same time, and thus can perform inspection in a short time. Further, in the case of photographing from directly below the back surface, there is a concern that droplets adhere to the image pickup section 140 and cause erroneous detection. In the present embodiment, since the imaging unit 140 captures images from the side surface of the substrate W, erroneous detection due to the adhesion of liquid droplets to the imaging unit 140 can be prevented.

(2) The image pickup unit 140 picks up an image of the side surface of the substrate W supported in a stationary state by the support unit 120 while stopping the supply of the cleaning liquid L by the supply unit 130. Therefore, the cleaning liquid L is not applied to the image pickup section 140 when the image is picked up from the side surface of the substrate W. In addition, the liquid surface is not shaken because it is stationary. Therefore, the determination unit 33 can accurately determine whether or not hydrophilization is possible.

(3) The supply unit 130 has a pair of nozzles 131, and the pair of nozzles 131 can discharge the cleaning liquid L toward the two polishing surfaces of the substrate W and are disposed at a position where the center of the substrate W is held. Therefore, the supply portion 130 flows the cleaning liquid L from two opposite directions, and the cleaning liquid L can spread over the entire substrate W.

(4) The supply unit 130 has nozzles 131 on both surfaces of the substrate W as polishing surfaces, and the nozzles 131 are provided at positions for supplying the cleaning liquid L to both of the opposite polishing surfaces of the substrate W. Therefore, the supply unit 130 supplies the cleaning liquid L to both of the opposite polishing surfaces, and the determination unit 33 can determine whether or not both of them can be hydrophilized.

(5) The imaging unit 140 is disposed around the substrate W. Therefore, the determination unit 33 can determine whether or not hydrophilization of the entire substrate W is possible.

(6) The determination unit 33 compares a reference image of the substrate W in a state where hydrophilization is performed by the cleaning liquid L with an image obtained by capturing an image of the substrate W in a state where the cleaning liquid L is supplied and supported by the support unit 120, and determines whether hydrophilization is possible. Therefore, the determination unit 33 can accurately determine whether or not hydrophilization is possible based on the image serving as the reference. Further, as a more specific example, the determination unit 33 extracts the contours of the substrate W and the cleaning liquid L from the captured image and the reference image, superimposes the captured image on the reference image so that the contours of the substrate W match, determines that the hydrophilization is insufficient in a portion of the captured image in which the distance between the contour of the cleaning liquid L and the contour of the substrate W is equal to or less than the first threshold value, and determines that the hydrophilization is impossible in a case where the ratio exceeds the second threshold value.

Modification example

The present embodiment is not limited to the above-described embodiment, and may be modified as follows.

(1) The method of determination by the determination unit 33 is not limited to the above-described configuration. The determination unit 33 may determine the portion where hydrophilization is not performed only from the captured image. For example, the determination unit 33 may determine whether or not hydrophilization is possible by the irregularities of the contour of the cleaning liquid L.

(2) The number of nozzles 131 for ejecting the cleaning liquid L to each polishing surface may be 1 or 3 or more, as long as the cleaning liquid L can be distributed over the entire polishing surface. The supplying portion 130 may be configured to supply the cleaning liquid L to only one of the polishing surfaces of the substrate W.

(3) The number of cameras 141 of the imaging unit 140 may be as large as possible to take an image from the side surface of the substrate W. Therefore, the number of cameras 141 may be 2 or less, or 4 or more. The optical axis of the camera 141 may not be strictly parallel to the abrasive surface, but may be slightly inclined.

(4) The substrate W may be rotated by a rotating device, and the supplying portion 130 may supply the cleaning liquid L to the substrate W. Thus, the cleaning liquid L can be easily spread over the entire polished surface of the substrate W regardless of the number of the nozzles 131.

(5) The brush cleaning device 210 may be configured to clean a surface of the substrate W with a cylindrical brush parallel to the surface.

(6) The supply of the cleaning liquid L by the supply unit 130 can be adjusted as follows, based on the determination result of whether or not the substrate W obtained by the determination unit 33 is hydrophilized. For example, when it is determined that hydrophilization is not possible on any of the front and back polishing surfaces of the substrate W, the supply amount or the supply time of the cleaning liquid L from the nozzle 131 facing the front and back polishing surfaces is increased. In addition, for example, when it is determined that hydrophilization is possible on any one of the front and back polishing surfaces of the substrate W, the supply amount or supply time of the cleaning liquid L from the nozzle 131 facing the front and back polishing surface is reduced or supply is stopped. For example, when a portion of the substrate W imaged by any one of the imaging units 140 is determined to be incapable of hydrophilizing, the supply amount or supply time of the cleaning liquid L from the nozzle 131 is added to the nozzle 131 capable of supplying the cleaning liquid L to the portion closest to the imaging unit 140, which is determined to be the portion incapable of hydrophilizing. For example, the amount or time of supply of the cleaning liquid L from the nozzle 131 to the nozzle 131 that is determined to be a portion that can be hydrophilized and is closest to the imaging unit 140 is reduced or the supply is stopped.

Other embodiments

While the embodiments and the modifications of the respective parts of the present invention have been described above, the embodiments and the modifications of the respective parts are presented as examples, and are not intended to limit the scope of the invention. The above-described novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims.

Claims (7)

1. A substrate cleaning apparatus, comprising:

a chamber into which a substrate having a polishing surface polished by a polishing device is carried;

a support unit which is provided in the chamber and supports the substrate;

a supply unit configured to supply a cleaning liquid for hydrophilizing the polishing surface to the polishing surface of the substrate supported by the support unit;

an imaging unit that photographs the polished surface to which the cleaning liquid is supplied from the side surface of the substrate;

a determination unit configured to determine whether or not hydrophilization is possible based on the image captured by the imaging unit;

an adjusting unit configured to adjust the supply of the cleaning liquid by the supplying unit, based on a determination result by the determining unit; and

and a cleaning unit connected to the chamber and configured to clean the polishing surface hydrophilized by the cleaning liquid.

2. The substrate cleaning apparatus according to claim 1, wherein the image pickup section picks up an image from a side surface of the substrate supported in a stationary state by the support section in a state where the supply of the cleaning liquid by the supply section is stopped.

3. The substrate cleaning apparatus according to claim 1 or 2, wherein,

the two sides of the substrate are grinding surfaces,

the supply unit has at least one pair of nozzles capable of ejecting the cleaning liquid toward at least one of the polishing surfaces of the substrate, and is disposed at a position where the center of the substrate is sandwiched.

4. The substrate cleaning apparatus according to claim 1, wherein,

the two sides of the substrate are grinding surfaces,

the supply unit has a nozzle provided at a position for supplying the cleaning liquid to both of the opposite polishing surfaces of the substrate.

5. The substrate cleaning apparatus according to claim 1, wherein the image pickup section is arranged in plural around the substrate.

6. The substrate cleaning apparatus according to claim 1, wherein the determination unit compares a reference image of the substrate, which is a reference in which the cleaning liquid is hydrophilized, with a captured image obtained by capturing an image of the substrate, which is supplied with the cleaning liquid and is supported by the support unit, to determine whether or not hydrophilization is possible.

7. The substrate cleaning apparatus according to claim 6, wherein the determination unit is

Extracting contours of the substrate and the cleaning liquid from the photographed image and the reference image, overlapping the photographed image and the reference image so that the contours of the substrate coincide,

in the captured image, a portion of the cleaning liquid having a distance equal to or less than a first threshold value from the contour of the substrate is determined to have insufficient hydrophilization,

a ratio of an area of the portion of the captured image where hydrophilization is insufficient to an area of the cleaning liquid in the reference image is obtained, and if the ratio exceeds a second threshold value, it is determined that hydrophilization is not performed.