Substrate processing device and substrate processing method

Abstract

A substrate processing device according to the present invention includes a holding unit, an image capturing unit, and an image processing unit. The image processing unit performs first processing for calculating a center position of a substrate on the basis of an image of an outer peripheral edge of the substrate, second processing for detecting a recessed curve along a recess located in a notched portion of the substrate from the image of the outer peripheral edge of the substrate, third processing for approximating, with quadratic curves, each of a plurality of recessed curves rotated within a given angle range, with the center position as the center, fourth processing for extracting an angle out of the given angle range at which the recessed curves and the quadratic curves are most closely approximated, fifth processing for calculating an extreme value position that is an extreme value of quadratic curve approximating most closely the recessed curve rotated at the extracted angle, and sixth processing for rotating the calculated extreme value position in a direction opposite to that in the fifth processing at the angle extracted in the fourth processing with the center position as the center, and setting the rotated extreme value position to a top position of the notched portion.

Description

SUBSTRATE PROCESSING APPARATUS AND SUBSTRATE PROCESSING METHOD

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

[0002] Conventionally, a technique for measuring the position of the tip of a notch formed in a substrate (hereinafter also referred to as the "top position") in order to perform rotational alignment of a substrate such as a semiconductor wafer has been known (see Patent Document 1).

[0003] Patent No. 6210525

[0004] The present disclosure provides a technique that can accurately measure the top position of a notch formed in a substrate.

[0005] A substrate processing apparatus according to one aspect of the present disclosure includes a holding unit, an imaging unit, and an image processing unit. The holding unit holds a substrate. The imaging unit images the substrate held by the holding unit. The image processing unit processes the image captured by the imaging unit. The image processing unit performs a first process, a second process, a third process, a fourth process, a fifth process, and a sixth process. The first process calculates a center position of the substrate based on an image of the outer periphery of the substrate captured by the imaging unit. The second process detects a recess curve along a recess located in a notch portion of the substrate from the image of the outer periphery of the substrate captured by the imaging unit. The third process approximates, with a quadratic curve, each of the recess curves rotated within a given angle range around the center position. The fourth process extracts an angle within the given angle range at which the recess curve and the quadratic curve are most similar. The fifth process calculates an extremum position that is an extremum of a quadratic curve that most closely approximates the concave curve rotated by the angle extracted in the fourth process. The sixth process rotates the extremum position calculated in the fifth process around the central position by the angle extracted in the fourth process in a direction opposite to that of the fifth process, and sets the rotated extremum position as the top position of the notch portion.

[0006] According to the present disclosure, the top position of a notch formed in a substrate can be measured with high accuracy.

[0007] FIG. 1 is a schematic plan view showing the configuration of a bonding system according to an embodiment. FIG. 2 is a schematic side view showing the configuration of a laminated substrate produced using the bonding system according to an embodiment. FIG. 3 is a flowchart showing the procedure of a process performed by the bonding system according to an embodiment. FIG. 4 is a schematic plan view showing the configuration of a bonding apparatus according to an embodiment. FIG. 5 is a side view showing the configuration of a main body of the bonding apparatus according to an embodiment. FIG. 6 is a plan view showing the configuration of an alignment mechanism of the bonding apparatus according to an embodiment. FIG. 7 is a plan view showing the imaging areas of four lower cameras according to an embodiment. FIG. 8 is a flowchart showing the procedure of a process performed by the bonding apparatus according to an embodiment. FIG. 9 is a flowchart showing the procedure of image processing performed by a control unit according to an embodiment. FIG. 10 is a diagram showing an example of an edge image obtained by capturing an image of a portion of the outer periphery of a support substrate other than a notch portion according to an embodiment. FIG. 11 is a diagram for explaining a first process according to an embodiment. FIG. 12 is a diagram showing an example of a notch image obtained by capturing an image of a portion of the outer periphery of a support substrate according to an embodiment. FIG. 13 is a diagram for explaining a second process according to an embodiment. FIG. 14 is a diagram for explaining a third process according to an embodiment. FIG. 15 is a diagram for explaining a fourth process according to an embodiment. FIG. 16 is a diagram for explaining a fifth process according to an embodiment. Fig. 17 is a diagram for explaining the sixth process according to the embodiment. Fig. 18 is a diagram showing the relationship between the top position set by the image processing according to the embodiment and the top position set by the image processing of the reference example.

[0008] Hereinafter, embodiments of a substrate processing apparatus and a substrate processing method disclosed herein will be described in detail with reference to the accompanying drawings. Note that the present disclosure is not limited to the embodiments described below. It should be noted that the drawings are schematic, and the dimensional relationships between elements, the ratios of elements, and the like may differ from reality.

[0009] Furthermore, the drawings may include portions with different dimensional relationships and ratios. In the following description, the X, Y, and Z directions are perpendicular to one another, the X and Y directions are horizontal directions, and the Z direction is vertical.

[0010] 2. Description of the Related Art Conventionally, a technique for measuring the top position of a notch formed in a substrate, such as a semiconductor wafer, is known in order to perform alignment in the rotational direction of the substrate.

[0011] On the other hand, in the conventional technology, if the notch portion of the substrate is captured at an angle in the image, there is a risk that the top position may not be recognized correctly.

[0012] Therefore, there is a need to realize a technology that overcomes the above-mentioned problems and can accurately measure the top position of a notch even when the notch of a substrate is imaged at an angle.

[0013] <Configuration of Bonding System> First, the configuration of a bonding system 1 according to an embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic plan view showing the configuration of the bonding system 1 according to an embodiment. Fig. 2 is a schematic side view showing the configuration of a laminated substrate T produced using the bonding system 1 according to an embodiment.

[0014] The bonding system 1 faces the bonding surface of the substrate W to the bonding surface of the support substrate S, and bonds the substrate W to the support substrate S via a bonding layer G (see FIG. 2 ), thereby producing a laminated substrate T. The bonding system 1 is an example of a substrate processing apparatus.

[0015] The substrate W to be processed is an example of a substrate on which elements, circuits, terminals, etc. are formed. The surface on which the elements, circuits, terminals, etc. are formed is the bonding surface. The surface of the substrate W opposite the bonding surface (hereinafter also referred to as the non-bonding surface) is polished after bonding, and the substrate W to be processed is thinned. After polishing, a surface electrode, a through electrode, etc. may be formed on the non-bonding surface of the substrate W to be processed. The substrate W to be processed may also be a stack of multiple substrates.

[0016] The support substrate S is an example of a substrate, and is bonded to the substrate to be processed W to temporarily reinforce the substrate to be processed W. After the substrate to be processed W is polished, the support substrate S is peeled off from the substrate to be processed W. The peeled support substrate S may be cleaned and then bonded to another substrate to be processed W.

[0017] 2, the laminated substrate T is composed of a substrate to be processed W, a support substrate S, and a bonding layer G. The bonding layer G bonds the substrate to be processed W and the support substrate S together, and includes, for example, an adhesive layer G1 and a release agent layer G2.

[0018] The adhesive layer G1 is formed, for example, by applying a first coating liquid containing an adhesive to the bonding surface of the workpiece substrate W, followed by heat treatment. The first coating liquid also contains an organic solvent that dissolves the adhesive. The adhesive may be either a thermosetting resin or a thermoplastic resin.

[0019] The release agent layer G2 is intended to facilitate smooth separation between the workpiece substrate W and the support substrate S. The release agent layer G2 is formed, for example, by applying a second coating liquid containing a release agent to the bonding surface of the support substrate S, followed by heat treatment. This second coating liquid also contains an organic solvent that dissolves the release agent.

[0020] This release agent has a lower adhesive strength than the adhesive described above. In order to increase the adhesive strength of the bonding layer G, the thickness of the release agent layer G2 may be thinner than the thickness of the adhesive layer G1.

[0021] As shown in FIG. 1, the bonding system 1 includes a loading / unloading station 2, a processing station 3, and a control device 5.

[0022] The loading / unloading station 2 loads / unloads the substrate to be processed W, the support substrate S, and the superposed substrate T into / from the processing station 3. The loading / unloading station 2 includes a cassette mounting table 10 and a transport device 20.

[0023] The cassette mounting table 10 includes a plurality of (for example, four) mounting sections 12. The mounting sections 12 are arranged at intervals in the Y direction, and the cassettes C are mounted on these mounting sections 12. Ｗ , C Ｓ , C Ｔ Cassette C is placed on the cassette. Ｗ accommodates a plurality of substrates W to be processed, and a cassette C Ｓ accommodates a plurality of support substrates S, and a cassette C Ｔ accommodates a plurality of laminated substrates T.

[0024] The laminated substrates T are classified into good and bad products, and the good products are placed in a cassette CＴ and cassette C for defective products. Ｔ The number of the mounting sections 12 is not limited to four.

[0025] The conveying device 20 conveys the cassette C on the placement unit 12. Ｗ , C Ｓ , C Ｔ and the processing station 3. The transport device 20 transports the substrate to be processed W, the support substrate S, and the superimposed substrate T between the processing station 3. The transport device 20 has a transport path 21 and a transport arm 22. The transport arm 22 is movable in the Y direction along the transport path 21. The transport arm 22 may be movable in the X direction and the Z direction, and may be rotatable about a rotation axis parallel to the Z direction.

[0026] The processing station 3 includes a first processing block B1, a second processing block B2, a third processing block B3, and a transport block B4. For example, the first processing block B1, the second processing block B2, and the third processing block B3 are detachable from the transport block B4.

[0027] The first processing block B1 includes a coating device 30 and a heat treatment device 50. The coating device 30 and the heat treatment device 50 are adjacent to the transport block B4.

[0028] The coating device 30 coats at least one of the substrate to be processed W and the support substrate S with a material for the bonding layer G. For example, the coating device 30 coats the substrate to be processed W with a first coating liquid. The coating device 30 also coats the support substrate S with a second coating liquid.

[0029] The heat treatment device 50 heat-treats the substrate W to be treated, which has been coated with the first coating liquid, to volatilize the organic solvent contained in the first coating liquid, thereby forming an adhesive layer G1 (see FIG. 2).The heat treatment device 50 also heat-treats the support substrate S to which the second coating liquid has been coated, to volatilize the organic solvent contained in the second coating liquid, thereby forming a release agent layer G2 (see FIG. 2).

[0030] The heat treatment devices 50 are, for example, stacked in four stages in the Z direction and arranged in two rows in the X direction. Each heat treatment device 50 has a heating section that heats at least one of the substrate to be treated W and the support substrate S. Each heat treatment device 50 may further have a cooling section that cools what has been heated by the heating section. The number and positions of the heat treatment devices 50 may vary widely.

[0031] The second processing block B2 includes a joining device 60. The joining device 60 is adjacent to the transport block B4.

[0032] The bonding device 60 faces the bonding surface of the substrate W to be processed and the bonding surface of the support substrate S, and bonds the substrate W to the support substrate S via a bonding layer G, thereby producing a laminated substrate T. For example, the bonding device 60 bonds the substrate W to the support substrate S under a reduced pressure atmosphere to prevent air bubbles from being trapped during bonding.

[0033] The bonding device 60 also performs heat treatment on the substrate to be processed W and the support substrate S, for example, to soften the bonding layer G. The detailed configuration of the bonding device 60 will be described later.

[0034] The third processing block B3 includes a transition device 70. The transition device 70 is, for example, stacked in two stages in the Z direction. The transition device 70 temporarily stores the target substrate W, the support substrate S, and the laminated substrate T, and transfers them to the transfer device 20 and the process transfer device 80.

[0035] The number and positions of the transition devices 70 may vary widely. The third processing block B3 may further include an inspection device that inspects the laminated substrate T for defects (such as air bubbles).

[0036] The transport block B4 has a process transport device 80. The process transport device 80 has a process transport arm 81. The process transport arm 81 transports the substrate to be processed W, the support substrate S, and the superimposed substrate T between the devices in the processing station 3. The process transport arm 81 may be movable in, for example, the X direction, the Y direction, and the Z direction, and may be rotatable about a rotation axis parallel to the Z direction.

[0037] The bonding system 1 also includes a control device 5. The control device 5 controls the operation of the bonding system 1. The control device 5 is, for example, a computer, and includes a control unit 6 and a storage unit 7. The storage unit 7 stores programs for controlling various processes such as the bonding process. The control unit 6 is an example of an image processing unit, and controls the operation of the bonding system 1 by reading and executing the programs stored in the storage unit 7. The control unit 6 may be one or more circuits, or may be provided as an integrated unit or partially separated.

[0038] The program read by the control unit 6 may be one that has been recorded on a computer-readable recording medium and that has been installed from that recording medium into the storage unit 7 of the control device 5. Examples of computer-readable recording media include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), and a memory card.

[0039] <Processing Executed by Bonding System> Next, details of the processing executed by the bonding system 1 according to the embodiment will be described with reference to Fig. 3. Fig. 3 is a flowchart showing the processing procedure executed by the bonding system 1 according to the embodiment. Here, the bonding method will be described with a focus on the substrates W to be processed.

[0040] 3, the processes executed by the bonding system 1 according to the embodiment include a carry-in process (step S101), a coating process (step S102), a heat treatment (step S103), a bonding process (step S104), and a carry-out process (step S105). Note that the various processes shown in FIG. 3 are executed based on the control of the control unit 6.

[0041] In the loading process (step S101), the control unit 6 controls the transport device 20 to load the substrate W to be processed into the cassette C on the platform 12. ＷThe control unit 6 then controls the process transport device 80 to transport the substrate W to be processed from the transition device 70 to the coating device 30.

[0042] In the coating process (step S102), the control unit 6 controls the coating device 30 to coat the first coating liquid on the bonding surface of the substrate to be processed W. After the first coating liquid is applied, the control unit 6 controls the process transport device 80 to transport the substrate to be processed W from the coating device 30 to the heat treatment device 50.

[0043] In the heat treatment (step S103), the control unit 6 heat-treats the substrate W to be treated, on which the first coating liquid has been applied, using the heat treatment device 50. In this heat treatment, the organic solvent contained in the first coating liquid is volatilized to form an adhesive layer G1. After this heat treatment, the control unit 6 controls the process transport device 80 to transport the substrate W to be treated from the heat treatment device 50 to the bonding device 60.

[0044] In this way, the substrates W to be processed are transferred to the cassette C Ｗ The substrate W is then taken out and transported to the coating device 30 and the heat treatment device 50 in that order. An adhesive layer G1 is formed on the bonding surface of the substrate W. Thereafter, the substrate W is transported to the bonding device 60.

[0045] During this time, the control unit 6 also transfers the support substrate S to the cassette C Ｓ and transports it successively to the coating device 30 and the heat treatment device 50. The control unit 6 controls the coating device 30 to coat the bonding surface of the support substrate S with the second coating liquid.

[0046] The control unit 6 also controls the heat treatment device 50 to heat-treat the support substrate S coated with the second coating liquid. In this heat treatment, the organic solvent contained in the second coating liquid is volatilized to form a release agent layer G2. Thereafter, the support substrate S is transported to the bonding device 60 by the process transport device 80.

[0047] In the bonding process (step S104), the control unit 6 controls the bonding device 60 to face the bonding surface of the substrate to be processed W and the bonding surface of the support substrate S, and bond the substrate to be processed W and the support substrate S via the bonding layer G, thereby producing a laminated substrate T. Details of this bonding process will be described later.

[0048] In the unloading process (step S105), the control unit 6 controls the process transport device 80 to transport the laminated substrate T from the bonding device 60 to the transition device 70. Next, the control unit 6 controls the transport device 20 to transport the laminated substrate T from the transition device 70 to the cassette C on the mount unit 12. Ｔ Transport to.

[0049] <Configuration of the joining device> Next, the configuration of the joining device 60 according to the embodiment will be described with reference to Fig. 4 to Fig. 7. Fig. 4 is a schematic plan view showing the configuration of the joining device 60 according to the embodiment.

[0050] 4, the bonding apparatus 60 includes a processing vessel 100 whose interior can be sealed. A loading / unloading port 101 is located on the side of the processing vessel 100 facing the process transport apparatus 80 (see FIG. 1), and the loading / unloading port 101 is provided with an opening / closing shutter (not shown).

[0051] The interior of the processing vessel 100 is divided into a pre-processing region D1 and a joining region D2 by a partition wall 103. A loading / unloading port 104 is formed in the partition wall 103.

[0052] The bonding apparatus 60 has a transfer unit 110 and a reversing unit 120 in the pre-processing area D1. The transfer unit 110 transfers the substrate to be processed W, the support substrate S, and the laminated substrate T to and from the process transport apparatus 80 via the loading / unloading port 101.

[0053] The delivery unit 110 has a delivery arm 111 and support pins 112. The delivery arm 111 delivers the substrate to be processed W, the support substrate S, and the overlapped substrate T between the process transport device 80 and the support pins 112. A plurality of support pins 112 (for example, three) are provided and support the substrate to be processed W, the support substrate S, and the overlapped substrate T.

[0054] The transfer section 110 is arranged in a plurality of stages, for example, in two stages, in the vertical direction, and can transfer any two of the substrate to be processed W, the support substrate S, and the superposed substrate T at the same time.

[0055] For example, the workpiece substrate W or the support substrate S before bonding may be transferred at one transfer part 110, and the bonded laminated substrate T may be transferred at another transfer part 110. Alternatively, the workpiece substrate W before bonding may be transferred at one transfer part 110, and the support substrate S before bonding may be transferred at another transfer part 110.

[0056] The inversion unit 120, for example, inverts the substrate W to be processed upside down so that the bonding surface of the substrate W faces downward. The inversion unit 120 has a holding arm unit 121 that holds the substrate W to be processed. The holding arm unit 121 is rotatable about a horizontal axis and is movable in the horizontal and vertical directions.

[0057] The inversion unit 120 rotates the holding arm unit 121 around a horizontal axis to invert the substrate W held by the holding arm unit 121 upside down. The holding arm unit 121 can also hold a support substrate S instead of the substrate W.

[0058] The reversing unit 120 has a detecting unit 122. The detecting unit 122 detects the position of the notch of the substrate (substrate to be processed W or support substrate S) held by the holding arm unit 121.

[0059] The inversion unit 120 rotates the substrate held horizontally by the holding arm unit 121 in a horizontal plane while detecting the position of the notch of the substrate using the detection unit 122, thereby adjusting the rotational position of the substrate held by the holding arm unit 121. The notch of the substrate indicates the crystal orientation of the substrate, etc.

[0060] The bonding apparatus 60 has a transfer section 130 and a main body section 150 in the bonding area D2. The transfer section 130 transfers the substrate to be processed W, the support substrate S, and the overlapped substrate T to the delivery section 110, the reversal section 120, and the main body section 150.

[0061] The transfer unit 130 includes two transfer arms 131 and 132. The transfer arms 131 and 132 are arranged in two vertical tiers in this order from bottom to top and are movable horizontally and vertically. The lower transfer arm 131 transfers, for example, a support substrate S from the inversion unit 120 to the main body unit 150. The upper transfer arm 132 transfers, for example, a substrate W to be processed from the inversion unit 120 to the main body unit 150.

[0062] The main body 150 is an example of a bonding section, and bonds the substrate to be processed W and the support substrate S. Fig. 5 is a side view showing the configuration of the main body 150 of the bonding apparatus 60 according to the embodiment.

[0063] As shown in FIG. 5, the main body 150 includes a chamber 151 , a decompression mechanism 157 , a lower chuck 161 , an upper chuck 162 , a pressure mechanism 170 , an alignment mechanism 180 , a lower camera 191 , and an upper camera 192 .

[0064] The chamber 151 is a processing vessel whose interior can be sealed, and is divided into a lower chamber portion 152 and an upper chamber portion 153. The lower chamber portion 152 accommodates a lower chuck 161 and the like. The upper chamber portion 153 accommodates an upper chuck 162 and the like.

[0065] The upper chamber portion 153 is raised and lowered relative to the lower chamber portion 152 by an elevation mechanism (not shown). By bringing the upper chamber portion 153 into contact with the lower chamber portion 152, an airtight space is formed inside the chamber 151. This airtight space is depressurized by a depressurization mechanism 157 such as a vacuum pump.

[0066] In the present disclosure, the upper chamber 153 is raised and lowered, but the lower chamber 152 may also be raised and lowered, or both may be raised and lowered. It is sufficient that the upper chamber 153 and the lower chamber 152 can be raised and lowered relative to each other.

[0067] The lower chuck 161 is a holding unit that holds the surface of the support substrate S opposite to the bonding surface with the bonding surface of the support substrate S facing upward. The lower chuck 161 has, for example, an electrostatic adsorption unit and a heating unit. The electrostatic adsorption unit electrostatically adsorbs the support substrate S. The heating unit heats the support substrate S to a predetermined temperature. The lower chuck 161 may have a vacuum adsorption unit instead of or in addition to the electrostatic adsorption unit.

[0068] The upper chuck 162 is a holding unit that holds the surface of the substrate W opposite to the bonding surface with the bonding surface of the substrate W facing downward. The upper chuck 162 has, for example, an electrostatic attraction unit and a heating unit. The electrostatic attraction unit electrostatically attracts the substrate W to be processed. The heating unit heats the substrate W to a predetermined temperature. The upper chuck 162 may have a vacuum attraction unit instead of or in addition to the electrostatic attraction unit.

[0069] In the embodiment, the lower chuck 161 holds the support substrate S and the upper chuck 162 holds the substrate W to be processed, but the lower chuck 161 may hold the substrate W to be processed and the upper chuck 162 may hold the support substrate S.

[0070] The pressurizing mechanism 170 lowers the upper chuck 162 in the chamber 151, thereby pressing the substrate W to be processed onto the support substrate S via the bonding layer G. The pressurizing mechanism 170 includes, for example, a pressure vessel 171 and a gas supply source 172. The pressure vessel 171 is expandable and contractible in the vertical direction. The gas supply source 172 supplies gas to the pressure vessel 171.

[0071] The pressure vessel 171 is made of, for example, a stainless steel bellows, etc. The lower end of the pressure vessel 171 is fixed to the upper chuck 162, and the upper end of the pressure vessel 171 is fixed to the chamber upper portion 153.

[0072] The pressurizing mechanism 170 adjusts the amount of gas in the pressure vessel 171 to expand and contract the pressure vessel 171 and raise and lower the chamber upper portion 153. The pressurizing mechanism 170 also adjusts the pressure inside the pressure vessel 171 to adjust the pressure bonding force between the substrate to be processed W and the support substrate S.

[0073] The alignment mechanism 180 aligns the support substrate S held by the lower chuck 161 with the substrate W to be processed held by the upper chuck 162. In this alignment, the position in the horizontal direction (position in the X direction and Y direction) and the position in the rotational direction around the vertical axis (position in the θ direction) are aligned.

[0074] The alignment mechanism 180 moves the chamber upper part 153 in the horizontal direction, thereby moving the upper chuck 162 in the horizontal direction. In addition, the alignment mechanism 180 rotates the chamber upper part 153 around a vertical axis, thereby rotating the upper chuck 162 around the vertical axis.

[0075] The alignment mechanism 180 has a plurality of (for example, five) mechanism groups, each of which is made up of a cam 181, a shaft 182, and a rotary motor 183. The rotary motor 183 rotates the cam 181 via the shaft 182. The center of the cam 181 is offset from the center of rotation.

[0076] 6 is a plan view showing the configuration of the alignment mechanism 180 of the bonding device 60 according to the embodiment. Two of the multiple cams 181 sandwich the upper chamber 153 from both sides in the X direction and rotate simultaneously to move the upper chamber 153 in the X direction. Another two of the multiple cams 181 sandwich the upper chamber 153 from both sides in the Y direction and rotate simultaneously to move the upper chamber 153 in the Y direction.

[0077] The remaining cam 181 of the multiple cams 181 is in contact with a blade portion 154 protruding from the outer peripheral surface of the chamber upper portion 153, and rotates to rotate the chamber upper portion 153 about the vertical axis. The blade portion 154 is pressed against the cam 181 by the elastic restoring force of the spring portion 155.

[0078] Returning to the description of Fig. 5, the lower camera 191 is an example of an imaging unit, and partially images the outer periphery of the support substrate S held by the lower chuck 161. The upper camera 192 is an example of an imaging unit, and partially images the outer periphery of the substrate to be processed W held by the upper chuck 162.

[0079] In addition, the arrangement of the support substrate S and the substrate to be processed W may be reversed, with the lower camera 191 capturing an image of the substrate to be processed W held by the lower chuck 161 and the upper camera 192 capturing an image of the support substrate S held by the upper chuck 162.

[0080] The lower camera 191 and the upper camera 192 are, for example, integrated and are moved horizontally together by a horizontal movement mechanism (not shown). The lower camera 191 and the upper camera 192 are freely movable between an imaging position where they image the support substrate S and the substrate to be processed W and a retracted position where they are retracted from the movement path of the chamber upper part 153.

[0081] In the present disclosure, the lower camera 191 and the upper camera 192 may be moved horizontally independently. In this case, the lower camera 191 and the upper camera 192 are caused to capture an image of a common target, and the relative position information between the lower camera 191 and the upper camera 192 is corrected.

[0082] Fig. 7 is a plan view showing the imaging areas 191A of the four lower cameras 191 according to the embodiment. Note that the imaging areas of the four upper cameras 192 (see Fig. 5) are similar to the imaging areas 191A of the four lower cameras 191 shown in Fig. 7, and therefore illustration and description thereof will be omitted.

[0083] 7 , the four lower cameras 191 capture images of four portions of the outer peripheral edge S1 of the support substrate S. For example, in the embodiment, the four lower cameras 191 are positioned such that, in a plan view, center lines 191L ​​of the imaging regions 191A of the four lower cameras 191 intersect at one point.

[0084] Of the four images captured by the four lower cameras 191, one is a notch image NP (see FIG. 12) that captures the area where the notch portion S3 is formed, and the remaining three are edge images EP (see FIG. 10) that capture the other areas.

[0085] The control unit 6 performs image processing on the three edge images EP to calculate the center position SC (see FIG. 11) of the support substrate S. The control unit 6 also performs image processing on one notch image NP to calculate the position of the top position S7 (see FIG. 17) of the notch portion S3, and calculates the position in the rotational direction on the support substrate S. Details of the method for calculating these positions will be described later.

[0086] In the embodiment, the control unit 6 functions as an image processing unit that calculates the center position SC of the support substrate S and the top position S7 of the notch portion S3, but an image processing unit may be provided separately from the control unit 6.

[0087] Furthermore, in the present disclosure, the number of lower cameras 191 is not limited to four. For example, the number of lower cameras 191 may be one, in which case the lower camera 191 is moved sequentially to the four imaging positions shown in Fig. 7. Furthermore, the number of lower cameras 191 may be five or more.

[0088] <Processing Executed by Bonding Apparatus> Fig. 8 is a flowchart showing the processing procedure of processing executed by the bonding apparatus 60 according to the embodiment. As shown in Fig. 8, the bonding processing executed by the bonding apparatus 60 includes a setting process (step S201), an imaging process (step S202), an image processing (step S203), an alignment process (step S204), and a superposition process (step S205).

[0089] In the setting process (step S201), the control unit 6 controls the inverting unit 120 to adjust the orientation of the substrate W in the horizontal plane and also invert the substrate W upside down so that the bonding surface of the substrate W faces downward. Thereafter, the control unit 6 controls the transport unit 130 to transport the substrate W from the inverting unit 120 to the upper chuck 162, and the substrate W is held by the upper chuck 162.

[0090] Also, in the processing of step S201, the control unit 6 controls the inversion unit 120 to adjust the orientation of the support substrate S in the horizontal plane, and then controls the transport unit 130 to transport the support substrate S from the inversion unit 120 to the lower chuck 161, and holds the support substrate S with the lower chuck 161.

[0091] In the imaging process (step S202), the control unit 6 controls the four lower cameras 191 to cause the lower cameras 191 to image four portions of the outer periphery S1 of the support substrate S. Of the four images captured by the lower cameras 191, one is a notch image NP (see FIG. 12 ) and the remaining three are edge images EP (see FIG. 10 ).

[0092] Furthermore, in the processing of step S202, the control unit 6 controls the four upper cameras 192 to cause the upper cameras 192 to capture images of four portions of the outer periphery of the substrate to be processed W. Of the four images captured by the upper cameras 192, one is a notch image and the remaining three are edge images.

[0093] In image processing (step S203), the control unit 6 processes the image captured in the imaging process (step S202) to calculate the center position SC (see FIG. 11) and position in the rotational direction of the support substrate S, as well as the center position and position in the rotational direction of the substrate to be processed W. This allows the relative positions of the support substrate S and the substrate to be processed W to be determined. Details of the processing in step S203 will be described later.

[0094] In the alignment process (step S204), based on the processing result of step S203, the control unit 6 aligns the target substrate W and the support substrate S using the alignment mechanism 180. In this alignment, the horizontal positions (positions in the X and Y directions) and the rotational positions around the vertical axis (position in the θ direction) are aligned.

[0095] In the polymerization process (step S205), the control unit 6 moves the lower camera 191 and the upper camera 192 from the imaging position to a retracted position, lowers the upper chamber portion 153 so that it abuts against the lower chamber portion 152, and forms an airtight space inside the chamber 151.

[0096] Thereafter, the control unit 6 controls the decompression mechanism 157 to decompress the sealed space inside the chamber 151, and the pressure mechanism 170 lowers the upper chuck 162 inside the chamber 151, thereby pressing the substrate W to be processed onto the support substrate S via the bonding layer G. As a result, a laminated substrate T is obtained.

[0097] <Details of Image Processing> Next, details of the process of calculating the center position SC (see FIG. 11) and rotational position of the support substrate S in the above-mentioned image processing (step S203) will be described with reference to FIGS. 9 to 18. Note that the process of calculating the center position and rotational position of the substrate W to be processed is the same as the process for the support substrate S described below, and therefore description thereof will be omitted.

[0098] 9 is a flowchart showing the processing procedure of the image processing (step S203) executed by the control unit 6 according to the embodiment. As shown in FIG. 9, in the image processing according to the embodiment, first, the control unit 6 performs a first process of calculating the center position of the support substrate S (step S301).

[0099] 10 is a diagram showing an edge image EP obtained by capturing an image of a portion of the outer peripheral edge S1 of the support substrate S according to the embodiment, excluding the notch portion S3. Note that in FIG. 10, for ease of viewing, the support substrate S is hatched to exaggerate the irregularities of the outer peripheral edge S1 of the support substrate S.

[0100] For example, in the process of step S301, the control unit 6 detects the outer periphery S1 captured in the edge image EP as shown in Fig. 10. Next, the control unit 6 calculates an approximate curve EP1 that approximates the outer periphery S1 to a circular arc shape.

[0101] Next, the control unit 6 calculates the position of an intersection S2 between the arc-shaped approximation curve EP1 and the image center line EP2. The image center line EP2 of the edge image EP corresponds to the center line 191L ​​(see FIG. 7) of the imaging area of ​​the lower camera 191 (see FIG. 7).

[0102] Finally, the control unit 6 calculates the center position SC of the support substrate S (see FIG. 10) as the center position SC of the support substrate S (see FIG. 10), which is the position of the center of the circle S1a that passes through the intersection S2 detected in each of the three edge images EP (see FIG. 10), as shown in FIG. 11. This completes the processing of step S301. FIG. 11 is a diagram for explaining the first processing according to the embodiment.

[0103] In the present disclosure, the means for calculating the position of the center position SC of the support substrate S is not limited to the above example, and various conventionally known methods may be used.

[0104] Returning to the description of Fig. 9, following the processing of step S301 described above, in the image processing according to this embodiment, the control unit 6 performs a second processing of detecting a curve along the recess located in the notch portion S3 of the support substrate S (hereinafter also referred to as a "recess curve") (step S302).

[0105] 12 is a diagram showing an example of a notch image NP obtained by capturing an image of the notch portion S3 of the outer peripheral edge S1 of the support substrate S according to the embodiment. Note that in FIG. 12, the support substrate S is hatched to make the drawing easier to see.

[0106] The control unit 6 performs various image processing on the notch image NP as shown in Fig. 12 to detect a recess curve S4 along the recess located in the notch portion S3 of the support substrate S as shown in Fig. 13. Fig. 13 is a diagram for explaining the second process according to the embodiment.

[0107] In the embodiment, for example, by detecting a location in the notch image NP where the difference in contrast between light and dark changes suddenly, the concave curve S4 located in the notch portion S3 is detected.

[0108] Returning to the description of Fig. 9, following the processing of step S302 described above, in the image processing according to this embodiment, the control unit 6 performs a third processing of approximating, with a quadratic curve, each of the plurality of recess curves S4 rotated at different angles around the center position SC (step S303).

[0109] 14 is a diagram illustrating the third process according to the embodiment. As shown in FIG. 14, in the process of step S303, the control unit 6 rotates the recess curve S4 detected in the process of step S302 within a given angle range R around the center position SC calculated in the process of step S301.

[0110] Note that various types of processing in the image processing of the present disclosure are performed in a given XY coordinate system as shown in Fig. 14. The X-axis direction and Y-axis direction in this XY coordinate system correspond to the row direction and column direction of a plurality of pixels arranged in a matrix in lower camera 191 (see Fig. 7) that captures notch image NP (see Fig. 12), for example.

[0111] For example, Fig. 14 shows concave curves S4a and S4b obtained by rotating the concave curve S4 detected in step S302 by angles +a and +2a, respectively. In the example of Fig. 14, the direction opposite to the clockwise direction is considered to be the positive rotation direction.

[0112] 14 also shows, as an example, recessed curves S4c and S4d obtained by rotating the recessed curve S4 detected in step S302 by angles −a and −2a, respectively. In this way, in the example of FIG. 14, the given angle range R is the range from angle −2a to angle +2a.

[0113] Then, in the processing of step S303, the degree of approximation between multiple concave curves S4 rotated at different angles in the XY coordinate system shown in Figure 14 and a quadratic curve S5 (see Figure 16) that approximates the concave curve S4 is evaluated.

[0114] For example, in the embodiment, the mean squared error (MSE) between the concave curve S4 and the quadratic curve S5 that approximates the concave curve S4 is calculated to evaluate the degree of similarity between the concave curve S4 and the quadratic curve S5.

[0115] In the present disclosure, the error function for evaluating the degree of approximation between the concave curve S4 and the quadratic curve S5 is not limited to the mean square error, and a wide variety of error functions may be used.

[0116] Returning to the description of Fig. 9, following the processing of step S303 described above, in the image processing according to this embodiment, the control unit 6 performs a fourth processing step (step S304) in which the control unit 6 extracts the angle at which the concave curve S4 and the quadratic curve S5 are most similar in the processing of step S303.

[0117] Figure 15 is a diagram for explaining the fourth processing according to the embodiment, and shows an example of the relationship between the rotation angle of the concave curve S4 (see Figure 14) rotated in the processing of step S303 and the MSE calculated in the processing of step S303.

[0118] In the example of Fig. 15, the MSE between the concave curve S4c (see Fig. 14) obtained by rotating the concave curve S4 by angle -a and the quadratic curve S5 approximating this concave curve S4c is smaller than the MSE of the concave curve S4 rotated by other angles. As a result, in the example of Fig. 15, the angle -a is extracted as the angle at which the multiple concave curves S4 and the quadratic curve S5 approximating the concave curve S4 are most similar.

[0119] In the above example, the angle −a with the smallest MSE is extracted from among five angles including 0 degree, but the present disclosure is not limited to this example. For example, in the results shown in FIG. 15 , the angle at which the minimum value of the approximation curve that most closely approximates all of the data may be extracted as the angle at which the multiple concave curves S4 and the quadratic curve S5 that approximates the concave curve S4 most closely approximate each other.

[0120] Returning to the description of Fig. 9, following the process of step S304 described above, in the image processing according to the embodiment, the control unit 6 performs a fifth process of calculating the position of the extremum of the quadratic curve S5 that most closely approximates the concave curve S4 rotated by the angle extracted in the process of step S304 (step S305).

[0121] 16A and 16B are diagrams for explaining the fifth process according to the embodiment. As shown in (a) of Fig. 16A, in the fifth process according to the embodiment, first, a quadratic curve S5c that most closely approximates the concave curve S4c rotated by an angle -a is calculated. Then, in the fifth process according to the embodiment, as shown in (b) of Fig. 16A, a position S6 of the extremum of the quadratic curve S5c (hereinafter also referred to as the "extremum position") is calculated.

[0122] In the example of Figure 16, an example has been shown in which the maximum value of the quadratic curve S5 is obtained as the extreme value in the fifth process, but the present disclosure is not limited to such an example, and the minimum value of the quadratic curve S5 may also be obtained as the extreme value.

[0123] Returning to the description of Fig. 9, following the process of step S305 described above, in the image processing according to this embodiment, the control unit 6 performs a sixth process of rotating the calculated extreme value position S6 in the reverse direction and setting the rotated extreme value position S6 as the top position S7 of the notch portion S3 (step S306).

[0124] Specifically, in the process of step S306, the control unit 6 rotates the extreme value position S6 around the center position SC by the angle extracted in the process of step S304 in the direction opposite to that in the process of step S305.

[0125] 17 is a diagram for explaining the sixth process according to the embodiment. For example, as shown in FIG. 17, the control unit 6 (see FIG. 1) rotates the extreme value position S6 around the center position SC in the direction opposite to the angle −a extracted in the process of step S304, i.e., by an angle +a, and sets the rotated extreme value position S6 as the top position S7 of the notch portion S3.

[0126] FIG. 18 is a diagram showing the relationship between the top position S7 set by the image processing according to the embodiment and the top position S7a set by the image processing according to the reference example.

[0127] As shown in FIG. 18, in the image processing of the reference example, the extreme position of a quadratic curve (not shown) that approximates the concave curve S4 of the notch portion S3 in the notch image NP is set to the top position S7a.

[0128] However, as shown in FIG. 18, if the concave curve S4 of the notch portion S3 is imaged at an angle in the notch image NP, the extreme position of the quadratic curve approximating the concave curve S4 will deviate from the actual top position of the notch portion S3.

[0129] On the other hand, in the image processing according to the embodiment, as described above, the control unit 6 reduces the slope of the concave curve S4 of the notch portion S3 captured at an angle by various image processes, and then calculates an extreme value position S6 of a quadratic curve S5 that approximates the reduced slope concave curve S4. Thereafter, the control unit 6 restores the slope of the calculated extreme value position S6 and sets the restored extreme value position S6 as the top position S7.

[0130] This makes it possible to measure the top position S7 of the notch portion S3 with high precision even when the notch portion S3 of the support substrate S is imaged at an angle.

[0131] 18, etc., the top position S7 of the notch portion S3 can be measured with high accuracy even if the entire notch portion S3, including the bottom portion, is not captured. Therefore, according to the embodiment, the magnification of the lower camera 191 can be increased, and the top position S7 of the notch portion S3 can be measured more accurately.

[0132] In addition, in an embodiment, in the processing of step S303, a given angle range R for rotating the recess curve S4 may be set based on the transport accuracy of the transport unit 130 that transports the support substrate S, etc. to the main body unit 150.

[0133] This allows the top position S7 of the notch portion S3 to be measured without making the given angle range R larger than necessary, thereby shortening the processing time for the joining process in the joining device 60.

[0134] In addition, in an embodiment, when bonding the support substrate S and the substrate to be processed W, the support substrate S and the substrate to be processed W may be bonded so that the top position S7 set on the support substrate S and the top position set on the substrate to be processed W are aligned.

[0135] This allows the support substrate S and the substrate W to be processed to be bonded with high precision.

[0136] In the above embodiment, an example is shown in which the angle at which the MSE is smallest is extracted in the process of step S303 and the process proceeds to the next step S304, but the present disclosure is not limited to this example.

[0137] For example, in the process of step S303, if the MSE is equal to or greater than a given threshold value at all rotation angles, the control unit 6 may determine that the tilt of the notch image NP is excessive and may notify an error to that effect externally, thereby enabling an operator or the like to know that there is an abnormality in the support state of the support substrate S.

[0138] Furthermore, in the above embodiment, a case where the technology of the present disclosure is applied in the positioning process when producing a laminated substrate T in which a support substrate S and a substrate to be processed W are bonded via a bonding layer G is shown, but the present disclosure is not limited to such an example.

[0139] For example, the technology of the present disclosure may be applied to a positioning step when preparing a laminated substrate in which a pair of substrates are directly bonded to each other by van der Waals forces, etc. This also allows the pair of substrates to be bonded to each other with high precision.

[0140] Furthermore, in the above embodiment, an example has been shown in which the technology of the present disclosure is applied to measuring the top position of a notch portion of a substrate during a bonding process of a pair of substrates, but the present disclosure is not limited to such an example.

[0141] For example, the technology of the present disclosure may be applied to measuring the top position of a notch portion of a substrate in various manufacturing processes for semiconductors, thereby enabling accurate positioning of the substrate in various semiconductor manufacturing processes.

[0142] The substrate processing apparatus (bonding system 1) according to the embodiment includes a holding unit (lower chuck 161), an imaging unit (lower camera 191), and an image processing unit (control unit 6). The holding unit (lower chuck 161) holds a substrate (support substrate S). The imaging unit (lower camera 191) images the substrate (support substrate S) held by the holding unit (lower chuck 161). The image processing unit (control unit 6) processes the image captured by the imaging unit (lower camera 191). The image processing unit (control unit 6) performs a first process (step S301), a second process (step S302), a third process (step S303), a fourth process (step S304), a fifth process (step S305), and a sixth process (step S306). The first process (step S301) calculates the center position SC of the substrate (support substrate S) based on an image of the outer periphery S1 of the substrate (support substrate S) captured by the imaging unit (lower camera 191). The second process (step S302) detects a recess curve S4 along a recess located in the notch portion S3 of the substrate (support substrate S) from the image of the outer periphery S1 of the substrate (support substrate S) captured by the imaging unit (lower camera 191). The third process (step S303) approximates each of the multiple recess curves S4 rotated within a given angle range R around the center position SC with a quadratic curve. The fourth process (step S304) extracts the angle within the given angle range R at which the recess curve S4 and the quadratic curve are most similar. The fifth process (step S305) calculates an extremum position S6, which is the extremum of the most approximate quadratic curve S5c, for the recess curve S4c rotated by the angle extracted in the fourth process (step S304). In the sixth process (step S306), the extreme value position S6 calculated in the fifth process is rotated around the center position SC by the angle extracted in the fourth process in the opposite direction to that in the fifth process, and the rotated extreme value position S6 is set as the top position S7 of the notch portion S3. This makes it possible to measure the top position S7 of the notch portion S3 with high accuracy.

[0143] The substrate processing apparatus (bonding system 1) according to the embodiment further includes a transport unit 130 that transports the substrate (support substrate S) to the holder (lower chuck 161). The given angle range R is set based on the transport accuracy of the transport unit 130. This allows the processing time of the bonding process in the bonding apparatus 60 to be shortened.

[0144] The substrate processing apparatus (bonding system 1) according to the embodiment further includes a bonding unit (main body 150) that bonds a pair of substrates (support substrate S, workpiece substrate W) together. The bonding unit (main body 150) bonds the pair of substrates (support substrate S, workpiece substrate W) together so that a top position S7 set on one substrate (support substrate S) is aligned with a top position set on the other substrate (workpiece substrate W). This allows the support substrate S and the workpiece substrate W to be bonded with high precision.

[0145] The substrate processing method according to the embodiment includes a first process (step S301), a second process (step S302), a third process (step S303), a fourth process (step S304), a fifth process (step S305), and a sixth process (step S306). The first process (step S301) calculates a center position SC of the substrate (support substrate S) based on a captured image of the outer periphery S1 of the substrate (support substrate S). The second process (step S302) detects a recess curve S4 along a recess located in a notch portion S3 of the substrate (support substrate S) from the captured image of the outer periphery S1 of the substrate (support substrate S). The third process (step S303) approximates each of the multiple recess curves S4 rotated within a given angle range R around the center position SC by a quadratic curve. In a fourth step (step S304), the angle at which the concave curve S4 and the quadratic curve are most similar within a given angle range R is extracted. In a fifth step (step S305), an extreme value position S6 is calculated, which is the extreme value of the quadratic curve S5c that most closely resembles the concave curve S4c rotated by the angle extracted in the fourth step (step S304). In a sixth step (step S306), the extreme value position S6 calculated in the fifth step is rotated around the center position SC by the angle extracted in the fourth step in the opposite direction to the fifth step, and the rotated extreme value position S6 is set as the top position S7 of the notch portion S3. This allows the top position S7 of the notch portion S3 to be measured with high accuracy.

[0146] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

[0147] The disclosed embodiments should be considered to be illustrative in all respects and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. The embodiments may be combined as appropriate within the scope of the appended claims.

[0148] REFERENCE SIGNS LIST 1 Bonding system (an example of a substrate processing apparatus) 6 Control unit (an example of an image processing unit) 130 Transport unit 150 Main body unit (an example of a bonding unit) 161 Lower chuck (an example of a holding unit) 162 Upper chuck (an example of a holding unit) 191 Lower camera (an example of an imaging unit) 192 Upper camera (an example of an imaging unit) S Support substrate (an example of a substrate) SC Center position S1 Outer periphery S3 Notch portion S4, S4c Concave curve S5, S5c Quadratic curve S6 Extreme value position S7 Top position W Substrate to be processed (an example of a substrate)

Claims

1. A device comprising: a holding unit that holds a substrate; an imaging unit that images the substrate held by the holding unit; and an image processing unit that processes the image captured by the imaging unit, wherein the image processing unit performs a first process of calculating a center position of the substrate based on an image of the outer periphery of the substrate captured by the imaging unit; a second process of detecting a recess curve along a recess located in a notch portion of the substrate from the image of the outer periphery of the substrate captured by the imaging unit; a third process of approximating, with a quadratic curve, a plurality of recess curves rotated within a given angle range around the center position; a fourth process of extracting an angle within the given angle range at which the recess curve and the quadratic curve are most similar; and a fifth process of calculating an extremum position of the most similar quadratic curve for the recess curve rotated by the angle extracted in the fourth process. and a sixth process of rotating the extreme value position calculated in the fifth process around the central position by the angle extracted in the fourth process in a direction opposite to that of the fifth process, and setting the rotated extreme value position as a top position of the notch portion.

2. The substrate processing apparatus according to claim 1, further comprising a transport unit that transports the substrate to the holder, wherein the given angle range is set based on the transport accuracy of the transport unit.

3. A substrate processing apparatus according to claim 1 or 2, further comprising a bonding section that bonds the pair of substrates together, the bonding section bonding the pair of substrates together so that the top position set on one of the substrates is aligned with the top position set on the other of the substrates.

4. A substrate processing method comprising: a first step of calculating a center position of a substrate based on an image of the outer periphery of the substrate; a second step of detecting, from the image of the outer periphery of the substrate, a recess curve that follows a recess located in a notch portion of the substrate; a third step of approximating, with a quadratic curve, each of the recess curves rotated within a given angle range around the center position; a fourth step of extracting, within the given angle range, an angle at which the recess curve and the quadratic curve are most similar; a fifth step of calculating, for the recess curve rotated by the angle extracted in step (4), an extreme value position that is the extreme value of the most approximate quadratic curve; and a sixth step of rotating the extreme value position calculated in step (5) around the center position by the angle extracted in step (4) in the opposite direction to step (5), and setting the rotated extreme value position as the top position of the notch portion.

Images