Substrate bonding apparatus and substrate bonding method

Abstract

The substrate bonding apparatus includes a bonding unit. The bonding unit is provided with: a first jig 11 that holds a first substrate W1; and a second jig (21) that holds the second substrate (W2). An actuator mechanism that bonds the first substrate (W1) held by the first jig (11) and the second substrate (W2) held by the second jig (21) by operating the first jig (11) and the second jig (21) relative to each other; and an inspection camera 43 that captures an image of the first substrate W1 and the second substrate W2 held by the second jig 21 in a state in which the first substrate W1 and the second substrate W2 are joined to each other.

Description

[0001] Related Application This application claims the benefit of priority based on Japanese Patent Application No. 2023-047373 and Japanese Patent Application No. 2023-047379, filed on March 23, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present invention relates to a substrate bonding apparatus and method for bonding two substrates. Examples of such substrates include semiconductor wafers, substrates for flat panel displays (FPDs) such as liquid crystal displays and organic EL (electroluminescence) displays, substrates for optical disks, magnetic disks, magneto-optical disks, photomask substrates, ceramic substrates, and solar cell substrates. Background Art

[0003] Patent Document 1 discloses a bonding system for bonding a first substrate and a second substrate to form a superimposed substrate. The bonding system comprises: a bonding device for bonding the hydrophilized first and second substrates by intermolecular forces; an inspection device for inspecting the bonding state of the superimposed substrates; and a transport device for transporting the superimposed substrates from the bonding device to the inspection device.

[0004] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Laid-Open No. 2020-181990. Summary of the Invention

[0005] Problems to be solved by the invention In the bonding system described in Patent Document 1, it is necessary to carry out the superposed substrates from the bonding apparatus and carry them into the inspection apparatus.

[0006] Embodiments of the present invention provide a substrate bonding apparatus and a substrate bonding method capable of shortening substrate transport time compared to conventional methods.

[0007] Means used to solve problems One embodiment of the present invention provides a substrate joining device, comprising a joining unit, wherein the joining unit includes: a first clamp for holding a first substrate; a second clamp for holding a second substrate; an actuator mechanism for causing the first clamp and the second clamp to move relative to each other, thereby joining the first substrate held by the first clamp and the second substrate held by the second clamp; and an inspection camera for photographing the first substrate and the second substrate held by the second clamp in a state of mutual joining.

[0008] In the embodiment, the substrate bonding device may include at least one of the following features.

[0009] The first substrate has a first bonding surface, on which at least one first alignment mark is formed; the second substrate has a second bonding surface, on which at least one second alignment mark is formed; the inspection camera is an infrared camera, which detects the first alignment mark and the second alignment mark when the first substrate and the second substrate are bonded.

[0010] The substrate bonding apparatus further includes an outer wall for accommodating the bonding unit, and the bonding unit further includes a chamber for accommodating the first jig, the second jig, and the inspection camera in the outer wall.

[0011] The joining unit further includes a pedestal disposed below the first jig, the second jig, and the inspection camera so as to overlap with the first jig, the second jig, and the inspection camera in a plan view.

[0012] The substrate bonding apparatus further includes a transfer robot configured to transfer a second first substrate to the first jig when the inspection camera captures an image of the first substrate and the second substrate held by the second jig.

[0013] The actuator mechanism includes a reversing actuator that reverses the second first substrate carried by the carrier to the first fixture and held by the first fixture when the inspection camera images the first substrate and the second substrate held by the second fixture.

[0014] The actuator mechanism also includes a horizontal actuator, which causes the second clamp to move horizontally relative to the first clamp between a joining position and a shooting position, wherein the joining position is a position where the first substrate held by the first clamp and the second substrate held by the second clamp are joined, and the shooting position is a position where the inspection camera shoots the first substrate held by the second clamp and the second substrate.

[0015] Another embodiment of the present invention provides a substrate bonding method, comprising: step a, bonding a first substrate and a second substrate by a bonding unit of a substrate bonding apparatus; and step b, inspecting the bonded first and second substrates by the bonding unit. The substrate bonding method may also incorporate at least one of the aforementioned features associated with the substrate bonding apparatus.

[0016] The process a includes: a process of holding the first substrate by a first clamp; a process of holding the second substrate by a second clamp; and a process of moving the first clamp and the second clamp relative to each other, thereby joining the first substrate held by the first clamp and the second substrate held by the second clamp. The process b includes a process of making an inspection camera photograph the first substrate and the second substrate held by the second clamp after the first substrate and the second substrate are joined. The substrate joining method also includes a process c of transporting the second first substrate to the first clamp by a transport robot while the inspection camera photographs the first substrate and the second substrate held by the second clamp.

[0017] The above-mentioned object and other objects, features and effects of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic plan view of a substrate bonding apparatus according to a first embodiment of the present invention.

[0019] Figure 2 This is a flowchart for explaining an example of a substrate bonding method performed by a substrate bonding apparatus.

[0020] Figure 3 It is a schematic diagram showing an example of the cross section of the first substrate and the second substrate before and after bonding.

[0021] Figure 4 It is a schematic top view of the first substrate for explaining the first alignment mark of the first substrate.

[0022] Figure 5 It is a schematic top view of the second substrate for explaining the second alignment mark of the second substrate.

[0023] Figure 6 Schematic diagram showing the first alignment mark and the second alignment mark before and after alignment adjustment of the first substrate and the second substrate.

[0024] Figure 7 A perspective view of the joining unit.

[0025] Figure 8 A top view of the joining unit.

[0026] Figure 9 This is a diagram of the bonding unit viewed horizontally from the Y direction.

[0027] Figure 10A A schematic top view of the first fixture.

[0028] Figure 10BA schematic top view of the first fixture.

[0029] Figure 11 This is a diagram of the first bonding module viewed horizontally from the X direction.

[0030] Figure 12 FIG. 4 is a top view of the first bonding module.

[0031] Figure 13 A top view of the first workbench.

[0032] Figure 14 For Figure 13 The direction of arrow XIV is shown when viewing the figure of the first workbench horizontally.

[0033] Figure 15 This is a diagram of the second bonding module viewed horizontally from the X direction.

[0034] Figure 16 To enlarge Figure 15 Part of the diagram.

[0035] Figure 17 FIG. 4 is a top view of the second bonding module.

[0036] Figure 18 This is a diagram of the second bonding module viewed horizontally from the Y direction.

[0037] Figure 19 A top view of the second workbench.

[0038] Figure 20 For Figure 19 The arrow XX shown is in the horizontal direction when viewing the second workbench.

[0039] Figure 21 A top view of the joining unit.

[0040] Figure 22 This is a diagram of the second camera photographing the second substrate while observing horizontally from the Y direction.

[0041] Figure 23 This is a diagram of the first camera photographing the first substrate viewed horizontally from the Y direction.

[0042] Figure 24 This is a diagram of an alignment camera photographing the first fixed reference member and the second fixed reference member as viewed horizontally from the Y direction.

[0043] Figure 25 For Figure 24 The arrow XXV is shown in the direction horizontally viewing the image towards the camera.

[0044] Figure 26This is a schematic diagram showing an example of an image of a cross-shaped first alignment mark generated by the first camera.

[0045] Figure 27 This is the block diagram of the displacement detector.

[0046] Figure 28 A diagram showing a vertical cross section of a displacement detector.

[0047] Figure 29 For Figure 28 The direction of arrow XXIX shown is a diagram of the displacement detector viewed vertically.

[0048] Figure 30 This is a block diagram showing the electrical configuration of a substrate bonding apparatus.

[0049] Figure 31A It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0050] Figure 31B It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0051] Figure 31C It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0052] Figure 31D It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0053] Figure 31E It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0054] Figure 31F It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0055] Figure 31G It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0056] Figure 31H It is a schematic diagram for explaining a first example of bonding the first substrate and the second substrate by the bonding unit.

[0057] Figure 32A It is a schematic diagram for explaining a second example of bonding the first substrate and the second substrate by the bonding unit.

[0058] Figure 32BIt is a schematic diagram for explaining a second example of bonding the first substrate and the second substrate by the bonding unit. DETAILED DESCRIPTION

[0059] Figure 1 It is a schematic plan view of the substrate bonding apparatus 1 according to the first embodiment of the present invention. Figure 2 It is a flowchart for explaining an example of a substrate bonding method performed by the substrate bonding apparatus 1 . Figure 3 It is a schematic diagram showing an example of the cross section of the first substrate W1 and the second substrate W2 before and after bonding.

[0060] The substrate bonding apparatus 1 is an apparatus for bonding two disc-shaped substrates W. Figure 1 As shown, a substrate bonding apparatus 1 includes: a plurality of load ports LP, each of which receives a plurality of carriers CA, such as FOUPs (Front Opening Unified Pods), for individually loading a plurality of substrates W; a plurality of processing units 2, which process the substrates W transferred from the load ports LP; and a transport system TS, which transports the substrates W between the load ports LP and the processing units 2, or between two processing units 2. The substrate bonding apparatus 1 also includes an outer wall 1a, which forms a sealed space that accommodates the plurality of processing units 2 and the transport system TS; and a control device 3, which controls the substrate bonding apparatus 1.

[0061] Figure 1 The example shown has three load ports LP. The three load ports LP include a first load port LP1, which receives a carrier CA holding a first substrate W1; a second load port LP2, which receives a carrier CA holding a second substrate W2; and a third load port LP3, which receives a carrier CA holding a first substrate W1 and a second substrate W2 to be bonded. The first and second load ports LP1 and LP2 serve as loading ports, receiving carriers CA holding substrates W to be bonded by the substrate bonding apparatus 1. The third load port LP3 serves as an unloading port, receiving a carrier CA holding two substrates W bonded by the substrate bonding apparatus 1.

[0062] The transport system TS transports the first substrate W1 and the second substrate W2 to be bonded from the first load port LP1 and the second load port LP2 to the plurality of processing units 2, and transports the bonded first substrate W1 and the second substrate W2 from the plurality of processing units 2 to the third load port LP3. The transport system TS may also include at least one transport robot TR that transports one or more substrates W in a horizontal position along a transport path TP.

[0063] The transport robot TR includes at least one robot hand TH that holds a substrate W in a horizontal posture. The transport robot TR moves along the transport path TP while holding the substrate W horizontally with the robot hand TH. Figure 1 The bold line in FIG represents the transport path TP. Figure 1 An example is shown in which the transfer path TP extends from the first load port LP1 and the second load port LP2 toward the plurality of processing units 2 and returns from the plurality of processing units 2 to the third load port LP3 .

[0064] The plurality of processing units 2 include: at least one cleaning unit 2c for cleaning the substrate W to be bonded; and at least one hydrophilizing unit 2h for making the bonding surfaces WA1 and WA2 of the substrate W to be bonded hydrophilic (see Figure 3 ) hydrophilization. The multiple processing units 2 also include: a flip unit for flipping one of the two substrates W to be bonded; a bonding unit 2b for bringing the bonding surfaces WA1 and WA2 of the two substrates W into contact with each other; and an inspection unit for inspecting the bonding accuracy of the two substrates W. Figure 1 The example in which the reversing unit and the inspection unit are part of the bonding unit 2b is shown. The reversing unit may also be a unit independent of the bonding unit 2b. The same applies to the inspection unit.

[0065] The multiple processing units 2 may further include a heating unit that heats the two substrates W bonded by the bonding unit 2b, thereby increasing the bonding strength between the two substrates W. The multiple processing units 2 may further include at least one pre-aligner that adjusts the position and angle of the substrates W before they are loaded into the bonding unit 2b, thereby minimizing the difference between the actual position and angle of the substrates W and their ideal position and angle. The pre-aligner can adjust the position and angle of the substrates W based on the periphery of the substrates W or on alignment marks described below. The thickness of the substrates W to be bonded can be measured in the pre-aligner or in another processing unit 2.

[0066] An example of the procedure for bonding two substrates W by the substrate bonding apparatus 1 is as follows. Specifically, a pre-cleaning step ( Figure 2 In step S1, in the pre-cleaning process, the first substrate W1 taken out from the carrier CA on the first load port LP1 and the second substrate W2 taken out from the carrier CA on the second load port LP2 are cleaned and dried. Thereafter, a hydrophilizing process ( Figure 2 In step S2, a post-cleaning step is performed to clean and dry the two hydrophilized substrates W ( Figure 2 Step S3).

[0067] After the two hydrophilized substrates W are cleaned, a reversing step is performed to reverse one of the two substrates W. Figure 2 Step S4). Then proceed to: alignment confirmation step ( Figure 2 Step S5), confirm the alignment of the two substrates W to be bonded; alignment adjustment step ( Figure 2 Step S6), adjusting the alignment of the two substrates W based on the confirmed alignment; and substrate contacting step ( Figure 2 In step S7, the two substrates W whose alignment has been adjusted are brought into contact. Then, the inspection process ( Figure 2 In step S8, the bonding accuracy of the two substrates W is checked, namely, the positional deviation of the two bonded substrates W and the angular deviation of the two bonded substrates W (about the center of the substrates W) are checked. The two bonded substrates W are then received on the carrier CA on the third load port LP3.

[0068] The pre-cleaning process can be either single-wafer cleaning or batch cleaning. Single-wafer cleaning involves supplying a cleaning solution or other processing liquid to multiple substrates W one by one. Batch cleaning involves simultaneously supplying a cleaning solution or other processing liquid to multiple substrates W arranged parallel to each other with a gap between them. The same applies to the post-cleaning process. Either the pre-cleaning process or the post-cleaning process can be single-wafer cleaning, while the other can be batch cleaning.

[0069] The pre-cleaning step and the post-cleaning step can be performed in the same cleaning unit 2c or in different cleaning units 2c. The cleaning unit 2c used to perform the pre-cleaning step on the first substrate W1 can be the same as or different from the cleaning unit 2c used to perform the pre-cleaning step on the second substrate W2. The same applies to the post-cleaning step. Figure 1 An example is shown in which the pre-cleaning step and the post-cleaning step of the first substrate W1 and the pre-cleaning step and the post-cleaning step of the second substrate W2 are performed in different cleaning units 2 c .

[0070] The hydrophilization step can be a plasma treatment in which plasma, such as oxygen plasma, is irradiated onto the bonding surfaces WA1 and WA2 of the substrates W. In some cases, moisture in the air and moisture supplied to the substrates W during the post-cleaning step come into contact with the plasma-irradiated bonding surfaces WA1 and WA2 of the substrates W, thereby forming hydrophilic groups, such as hydroxyl groups (OH groups), on the bonding surfaces WA1 and WA2 of the substrates W. The hydrophilization step can also be a wet treatment in which a hydrophilizing liquid is supplied to the bonding surfaces WA1 and WA2 of the substrates W, and this hydrophilizing liquid forms hydrophilic groups on the bonding surfaces WA1 and WA2 of the substrates W. In some cases, the hydrophilization unit 2h can perform at least one of a pre-cleaning step and a post-cleaning step in addition to the hydrophilization step. If the hydrophilization unit 2h performs both the pre-cleaning step and the post-cleaning step, the cleaning unit 2c can be omitted.

[0071] The hydrophilization process can be performed either individually or in batches. The individual hydrophilization process hydrophilizes multiple substrates W one by one, while the batch hydrophilization process simultaneously hydrophilizes multiple substrates W arranged parallel to each other with a gap between them. The hydrophilization unit 2h performing the hydrophilization process on the first substrate W1 can be the same as or different from the hydrophilization unit 2h performing the hydrophilization process on the second substrate W2. Figure 1 An example of the latter is shown.

[0072] exist Figure 1 In the example shown, the alignment confirmation step, alignment adjustment step, and substrate contact step are performed by the bonding unit 2b. In this example, the bonding unit 2b also performs the flipping step and the inspection step. The alignment confirmation step is the following step: based on the alignment marks (refer to Figure 4 ) image to confirm the alignment of the two substrates W to be bonded. The substrate contact step is a step in which the two substrates W, whose alignment has been adjusted, are brought into contact, thereby bonding the two substrates W. The allowable bonding accuracy (tolerance of the two bonded substrates W) is, for example, ±100 nm, but may be ±10 nm depending on the situation.

[0073] The substrate contact step can be a step of directly bonding the two substrates W in an atmosphere at room temperature. The substrate contact step can be a face-to-face bonding step in which the two substrates W are bonded so that their front surfaces face each other. In some cases, the front surfaces of the two substrates W correspond to the bonding surfaces WA1 and WA2 of the two substrates W. The substrate contact step can be a step of bonding the two substrates W without pressing one substrate W against the other, or by pressing one substrate W against the other with a pressure that does not damage devices formed on the two substrates W.

[0074] Figure 3 The cross section of the first substrate W1 and the second substrate W2 cut along a plane perpendicular to the first substrate W1 and the second substrate W2 is shown. Figure 3 The ratio of the thickness of the device layers WC1 and WC2 to the thickness of the bonding layers WB1 and WB2 shown is not limited to the actual ratio. Figure 3 The left side of the figure shows an example of a hydroxyl group, an example of a hydrophilic group, formed on the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 before bonding. In this example, the oxygen atoms (O) in the hydroxyl group are bonded to the silicon atoms (Si) in the bonding layers WB1 and WB2.

[0075] Before bonding, the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are terminated with multiple hydroxyl groups. When the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are brought into contact, the first and second substrates W1 and W2 are bonded together by intermolecular forces acting between the two hydroxyl groups. Depending on the situation, water molecules detach from the two hydroxyl groups, and silicon atoms in the bonding layer WB1 of the first substrate W1 and silicon atoms in the bonding layer WB2 of the second substrate W2 are bonded via oxygen atoms. In this way, the first and second substrates W1 and W2 are bonded.

[0076] Next, the substrate W and the alignment mark will be described.

[0077] Figure 4 1 is a schematic plan view of the first substrate W1 for explaining the first alignment mark AM1 of the first substrate W1. Figure 5 1 is a schematic top view of the second substrate W2 for explaining the second alignment mark AM2 of the second substrate W2.

[0078] exist Figure 4 as well as Figure 5 In the figure, the first alignment mark AM1 and the second alignment mark AM2 are exaggerated for easy understanding. The size of the alignment mark relative to the substrate W is not limited to Figure 4 as well as Figure 5 The configuration of the alignment marks relative to the substrate W and the number of alignment marks provided on a substrate W are not limited to Figure 4 as well as Figure 5 Example shown.

[0079] like Figure 4 as well as Figure 5 As shown, the first substrate W1 and the second substrate W2 are flat circular plates with equal diameters. The diameters of the first substrate W1 and the second substrate W2 can be 300 mm or other diameters. The thermal expansion coefficient of the first substrate W1 can be the same as or different from the thermal expansion coefficient of the second substrate W2. The first substrate W1 includes a circular plate-shaped base material WD1, and the second substrate W2 includes a circular plate-shaped base material WD2 (see Figure 3 ). The substrate WD1 and the substrate WD2 are made of semiconductors such as single crystal silicon. The substrate WD1 and the substrate WD2 may also be made of materials other than semiconductors.

[0080] Substrates WD1 and WD2 each include a parallel, circular front and back surface, and an annular end surface connecting the outer edges of the front and back surfaces. The front and back surfaces of substrates WD1 and WD2 are parallel, flat surfaces. The front surfaces of substrates WD1 and WD2 are device-forming surfaces on which devices are formed. The back surfaces of substrates WD1 and WD2 are non-device-forming surfaces on which no devices are formed. Both the front and back surfaces of substrates WD1 or WD2 may also be device-forming surfaces.

[0081] The outer periphery of the substrate WD1 is formed with a V-shaped notch that opens at the end face of the substrate WD1 when viewed perpendicular to the front face of the substrate WD1. Alternatively, the outer periphery of the substrate WD1 may have an orientation flat (also known as an orientation plane) instead of a notch. The notch and the orientation plane indicate the crystal orientation of the substrate WD1. The first substrate W1 is positioned circumferentially of the first substrate W1 using the notch or the orientation plane as a reference. The same applies to the second substrate W2.

[0082] The first substrate W1 includes at least one first alignment mark AM1 that serves as a reference for aligning the first substrate W1. The first substrate W1 also includes at least one device such as a transistor or a capacitor formed on the front surface of the substrate WD1. The first alignment mark AM1 may be a part of the device or a structure unrelated to the device. The position of the first substrate W1 in a direction parallel to the front surface of the first substrate W1 and the angle of the first substrate W1 around a vertical line orthogonal to the central portion of the front surface of the first substrate W1 are determined based on at least one first alignment mark AM1 provided on the first substrate W1. As long as the position of the first substrate W1 and the angle of the first substrate W1 can be determined, the shape and number of the first alignment mark AM1 are arbitrary. The same applies to the second alignment mark AM2.

[0083] The first substrate W1 includes: a device layer WC1 (refer to Figure 3 ), covering the front surface of the substrate WD1; and the bonding layer WB1 (refer to Figure 3 ), covering the front surface of the device layer WC1. A first alignment mark AM1 is located on the device layer WC1. Devices such as transistors are also located on the device layer WC1. The first alignment mark AM1 and the devices are covered by a bonding layer WB1. The bonding layer WB1 is a transparent or semi-transparent insulating layer. The bonding layer WB1 can be a silicon oxide film or a thin film of a substance other than silicon oxide. In the former case, the bonding layer WB1 can also be a silicon oxide film made using TEOS (tetraethoxysilane). The same applies to the second substrate W2.

[0084] The front and back sides of the first substrate W1 are two parallel planes. The back side of the first substrate W1 is a plane on the opposite side of the front side of the first substrate W1. The bonding surface WA1 is the front side of the first substrate W1 that contacts the ambient gas in the space where the first substrate W1 is arranged. When the bonding surface WA1 of the first substrate W1 faces upward, the bonding surface WA1 of the first substrate W1 is equivalent to the upper surface of the first substrate W1, and the back side of the first substrate W1 is equivalent to the lower surface of the first substrate W1. The front side of the bonding layer WB1 is equivalent to the bonding surface WA1 of the first substrate W1. The bonding surface WA1 can be a circular plane parallel to the front side of the substrate WD1 that covers the entire area of ​​the front side of the substrate WD1, or it can be a plane parallel to the front side of the substrate WD1 that covers only a part of the front side of the substrate WD1. The same applies to the second substrate W2.

[0085] Figure 4 as well as Figure 5 In the example shown, four first alignment marks AM1 having the same shape and size are provided on the first substrate W1 , and four second alignment marks AM2 having the same shape and size are provided on the second substrate W2 . Figure 4 An example is shown in which the first alignment mark AM1 is in a cross shape. Figure 5 An example is shown in which the second alignment mark AM2 includes four L-shaped figures, and the four L-shaped figures are arranged one at each of the four corners of the same rectangle so as to follow any two of the four sides of the rectangle.

[0086] Alignment marks can be as Figure 4 As shown, it is composed of a continuous graph, or it can be Figure 5 In the case where a plurality of alignment marks are formed on a substrate W, the alignment marks may also be circular or ring-shaped.

[0087] The alignment mark is preferably shaped so as to define a height direction and a width direction that are orthogonal to each other. The height direction and the width direction of the alignment mark are parallel to the front surface of the substrate W and are orthogonal to each other. In the case where the alignment mark is in the shape of a cross, the direction parallel to the vertical line of the alignment mark is the height direction of the alignment mark, and the direction parallel to the horizontal line of the alignment mark is the width direction of the alignment mark. Figure 4 In the figure, the up-down direction is the height direction of the alignment mark, and the left-right direction is the width direction of the alignment mark. Figure 5 As shown, when the alignment mark includes four L-shaped figures arranged at the four corners of a laterally long rectangle, the direction parallel to the short side of the rectangle is the height direction of the alignment mark, and the direction parallel to the long side of the rectangle is the width direction of the alignment mark.

[0088] Figure 4The centers of gravity AG1 of the four first alignment marks AM1 shown are arranged at 90-degree intervals on a circle concentric with the first substrate W1. Figure 5 The centers of gravity AG2 of the four second alignment marks AM2 are arranged at 90-degree intervals on a circle concentric with the second substrate W2. The longitudinal axis AV1, the transverse axis AH1 and the reference point AP1 of the first substrate W1 are based on Figure 4 The four first alignment marks AM1 shown are determined. The longitudinal axis AV2, the transverse axis AH2 and the reference point AP2 of the second substrate W2 are based on Figure 5 Four second alignment marks AM2 are shown.

[0089] The longitudinal axis AV1, the transverse axis AH1, and the reference point AP1 of the first substrate W1 are all virtual straight lines or points set on the front surface of the first substrate W1. The longitudinal axis AV1 and the transverse axis AH1 are reference lines representing the angle of the first substrate W1. The longitudinal axis AV1 is a straight line passing through the center of gravity AG1 of two different first alignment marks AM1 with an angle of 180 degrees around the center of the first substrate W1. The transverse axis AH1 is a straight line passing through the center of gravity AG1 of the remaining two first alignment marks AM1. The longitudinal axis AV1 and the transverse axis AH1 are straight lines that are orthogonal to each other. The reference point AP1 is the intersection of the longitudinal axis AV1 and the transverse axis AH1. The center of the first substrate W1 is determined based on the outline of the first substrate W1. The reference point AP1 may or may not be consistent with the center of the first substrate W1.

[0090] The longitudinal axis AV2, the transverse axis AH2, and the reference point AP2 of the second substrate W2 are all virtual straight lines or points set on the front surface of the second substrate W2. The longitudinal axis AV2 and the transverse axis AH2 are reference lines representing the angle of the second substrate W2. The longitudinal axis AV2 is a straight line passing through the center of gravity AG2 of two different second alignment marks AM2 with an angle of 180 degrees around the center of the second substrate W2. The transverse axis AH2 is a straight line passing through the center of gravity AG2 of the remaining two second alignment marks AM2. The longitudinal axis AV2 and the transverse axis AH2 are straight lines that are orthogonal to each other. The reference point AP2 is the intersection of the longitudinal axis AV2 and the transverse axis AH2. The center of the second substrate W2 is determined based on the outline of the second substrate W2. The reference point AP2 may or may not be consistent with the center of the second substrate W2.

[0091] When joining two substrates W, that is, when joining the first substrate W1 and the second substrate W2, alignment adjustment is performed to minimize the positional deviation of the first substrate W1 and the second substrate W2 while the joining surface WA1 of the first substrate W1 and the joining surface WA2 of the second substrate W2 are facing each other. Figure 4 as well as Figure 5In the example shown, the relative positions of the first substrate W1 and the second substrate W2 are adjusted so that the distance between the reference point AP1 of the first substrate W1 and the reference point AP2 of the second substrate W2 is reduced, the angle between the horizontal axis AH1 of the first substrate W1 and the horizontal axis AH2 of the second substrate W2 is reduced, and the angle between the vertical axis AV1 of the first substrate W1 and the vertical axis AV2 of the second substrate W2 is reduced.

[0092] Alternatively, the distance between reference point AP1 and reference point AP2, the angle between vertical axis AV1 and vertical axis AV2, and the angle between horizontal axis AH1 and horizontal axis AH2 may be comprehensively considered to determine whether the positional deviation between the first substrate W1 and the second substrate W2 has been minimized. Specifically, when the positional deviation between the first substrate W1 and the second substrate W2 has been minimized, at least one of the distance between reference point AP1 and reference point AP2, the angle between vertical axis AV1 and vertical axis AV2, and the horizontal axis AH1 and horizontal axis AH2 does not necessarily need to be minimized.

[0093] The method for performing alignment adjustment between the first substrate W1 and the second substrate W2 is not limited to the method described above. For example, if the first substrate W1 and the second substrate W2 are each provided with three or more alignment marks of the same number, the relative position of the first substrate W1 and the second substrate W2 can be adjusted by minimizing the sum or average of the distances between the center of gravity AG1 of the first alignment mark AM1 on the first substrate W1 and the center of gravity AG2 of the second alignment mark AM2 on the second substrate W2, rather than using reference lines such as the vertical axis AV1 and the vertical axis AV2 and the horizontal axis AH1 and the horizontal axis AH2. Alternatively, the relative position of the first substrate W1 and the second substrate W2 can be adjusted by minimizing the distance between an approximate curve or straight line calculated using a least squares method based on the center of gravity AG1 of the plurality of first alignment marks AM1 on the first substrate W1 and an approximate curve or straight line calculated using the same method based on the center of gravity AG2 of the plurality of second alignment marks AM2 on the second substrate W2.

[0094] Figure 6 Schematic diagram showing the first alignment mark AM1 and the second alignment mark AM2 before and after alignment adjustment of the first substrate W1 and the second substrate W2. Figure 6 The left side of FIG shows the first alignment mark AM1 and the second alignment mark AM2 before the alignment adjustment of the first substrate W1 and the second substrate W2. In this example, the center of gravity AG1 of the first alignment mark AM1 is offset from the center of gravity AG2 of the second alignment mark AM2, and the first alignment mark AM1 is tilted relative to the second alignment mark AM2. Figure 6As shown on the right side of , if alignment adjustment is performed, the center of gravity AG1 of the first alignment mark AM1 coincides with the center of gravity AG2 of the second alignment mark AM2, and the direction of the first alignment mark AM1 coincides with the direction of the second alignment mark AM2.

[0095] Next, the joining unit 2b will be described.

[0096] Figure 7 2b is a perspective view of the joining unit 2b. Figure 8 2b is a top view of the bonding unit 2b. Figure 9 This is a diagram of the bonding unit 2b viewed horizontally from the Y direction.

[0097] In the following example, the first clamp 11 can rotate around a horizontal straight line. In the following, unless otherwise specified, the first clamp 11 in the carry-in / carry-out state is described. The carry-in / carry-out state of the first clamp 11 is as follows: the center line 11c of the first clamp 11 (refer to Figure 9 ) is vertical, and the first adsorption surface 11s of the first fixture 11 (refer to Figure 9 ) facing upward.

[0098] The X and Y directions are horizontal directions that are perpendicular to each other. The Z direction is a vertical direction that is perpendicular to the X and Y directions. The X, Y, and Z directions correspond to the left-right, front-back, and top-bottom directions of the joining unit 2b, respectively. The positive sides of the X, Y, and Z directions correspond to the right, front, and top of the joining unit 2b, respectively.

[0099] like Figures 7 to 9 As shown, the bonding unit 2b includes: a first bonding module 2b1, including a first clamp 11 for holding the first substrate W1; a second bonding module 2b2, including a second clamp 21 for holding the second substrate W2; an actuator mechanism AC, which moves at least one of the first clamp 11 and the second clamp 21; and a base 20, which supports the first bonding module 2b1 and the second bonding module 2b2.

[0100] The first jig 11 and the second jig 21 are positioned above a pedestal 20. The pedestal 20 is positioned between the floor of the clean room where the substrate bonding apparatus 1 is installed and the first jig 11 and the second jig 21. The pedestal 20 is a common component for the first bonding module 2b1 and the second bonding module 2b2. The pedestal 20 can be a single, integrated component or comprised of multiple, mutually fixed components.

[0101] like Figure 9As shown, the joining unit 2b may also include a vibration isolation table 10 for reducing vibration of the pedestal 20. The vibration isolation table 10 may include a vibration sensor for detecting vibration of at least one of the clean room floor and the pedestal 20; and a vibration isolation actuator for moving the pedestal 20 based on the detection value of the vibration sensor, thereby reducing vibration of the pedestal 20. The vibration isolation table 10 is disposed between the clean room floor and the pedestal 20. The pedestal 20 is supported by the vibration isolation table 10.

[0102] The joining unit 2b may include a chamber 9 for accommodating the first clamp 11 and the second clamp 21. The chamber 9 includes: a box-shaped partition 9p, which is provided with a carry-in / out port for the substrate W to pass through; and a baffle 9s, which opens and closes the carry-in / out port. The partition 9p may include a carry-in / out port for both the first substrate W1 and the second substrate W2 to pass through, or may include a carry-in / out port for the first substrate W1 to pass through and a carry-in / out port for the second substrate W2 to pass through. In the latter case, it is sufficient to provide a baffle 9s at each carry-in / out port. The equipment in the chamber 9, such as the first clamp 11, is connected to the cleaning unit 2c (refer to Figure 1 ) and other processing units 2 other than the bonding unit 2b are isolated.

[0103] At least one of the first jig 11 and the second jig 21 is movable in the Y direction relative to the stage 20. Similarly, at least one of the first jig 11 and the second jig 21 is movable in the X direction relative to the stage 20. At least one of the first jig 11 and the second jig 21 is movable in the Z direction relative to the stage 20. Figures 7 to 9 In the example shown, the first jig 11 is movable in the Z direction relative to the stage 20 , and the second jig 21 is movable in the X direction and the Y direction relative to the stage 20 .

[0104] As long as the first jig 11 and the second jig 21 are relatively movable in the X, Y, and Z directions, the directions in which the first jig 11 and the second jig 21 can move relative to the stage 20 are not limited to the aforementioned directions. For example, as long as one of the first jig 11 and the second jig 21 is movable relative to the stage 20 in the X, Y, and Z directions, the other of the first jig 11 and the second jig 21 may not be movable relative to the stage 20 in the X, Y, and Z directions.

[0105] The first clamp 11 and the second clamp 21 are vacuum clamps that hold the first substrate W1 by suction force generated by gas suction, or electrostatic clamps that hold the first substrate W1 by electrical attraction. As long as the first substrate W1 and the second substrate W2 can be fixed to the first clamp 11 and the second clamp 21, the first clamp 11 and the second clamp 21 may also be clamps other than these clamps.

[0106] like Figure 8 As shown, the first clamp 11 includes a first suction surface 11s that contacts the lower surface of the first substrate W1. Similarly, the second clamp 21 includes a second suction surface 21s that contacts the lower surface of the second substrate W2. The centerline 11c of the first clamp 11 is a straight line passing through the center of the first suction surface 11s and perpendicular to the first suction surface 11s. The centerline 21c of the second clamp 21 is a straight line passing through the center of the second suction surface 21s and perpendicular to the second suction surface 21s.

[0107] Figures 7 to 9 The following example is shown: the first attraction surface 11s and the second attraction surface 21s are circular, horizontal planes, each having a diameter greater than the diameter of the first substrate W1 and the second substrate W2. In this example, the first substrate W1 is placed on the first attraction surface 11s so that the center of the first substrate W1 is aligned with the center of the first attraction surface 11s. Similarly, the second substrate W2 is placed on the second attraction surface 21s so that the center of the second substrate W2 is aligned with the center of the second attraction surface 21s. As a result, the lower surface of the first substrate W1 is in contact with the first attraction surface 11s, and the lower surface of the second substrate W2 is in contact with the second attraction surface 21s.

[0108] The first adsorption surface 11s may be a shape other than a circle, or a shape other than a horizontal plane. The same applies to the second adsorption surface 21s. For example, when the first fixture 11 is in the moving-in and moving-out state, the first adsorption surface 11s may be a spherical curved surface convex toward the top or a circular curved surface curved into an arc shape, and may also include a horizontal portion and a non-horizontal portion. The same applies to the second adsorption surface 21s. The non-horizontal portion may be a plane inclined at a certain angle relative to the horizontal plane or a curved surface whose inclination angle relative to the horizontal plane continuously changes, or may be a surface other than these surfaces. Alternatively, one of the first adsorption surface 11s and the second adsorption surface 21s may be a horizontal plane, and the other of the first adsorption surface 11s and the second adsorption surface 21s may be a shape other than a horizontal plane.

[0109] The first substrate W1 and the second substrate W2 are flat when they are transported to the joining unit 2b. Even if there is warping in the first substrate W1 and the second substrate W2, the amount of warping is so small that the first substrate W1 and the second substrate W2 are substantially considered flat. In the case where the first adsorption surface 11s is a shape other than a horizontal plane, if the first substrate W1 is placed on the first clamp 11, the first adsorption surface 11s is partially in contact with the lower surface of the first substrate W1, and a gap is formed between the lower surface of the first substrate W1 and the first adsorption surface 11s of the first clamp 11. If the first clamp 11 adsorbs the first substrate W1, the upper surface and the lower surface of the first substrate W1 are elastically deformed into the same or substantially the same shape as the first adsorption surface 11s, thereby increasing the contact area between the lower surface of the first substrate W1 and the first adsorption surface 11s of the first clamp 11. The same applies to the case where the second adsorption surface 21s is a shape other than a horizontal plane.

[0110] The first adsorption surface 11s may include multiple adsorption areas, each of which generates and stops generating adsorption force independently of the other adsorption areas. The adsorption force holds the first substrate W1 on the first adsorption surface 11s. The same applies to the second adsorption surface 21s. The adsorption area is an area that generates suction force regardless of whether other adsorption areas generate adsorption force. The multiple adsorption areas of the first adsorption surface 11s may be as follows: Figure 10A As shown, it extends radially from the center of the first adsorption surface 11s, or as shown Figure 10B The plurality of adsorption regions of the first adsorption surface 11s may be arranged and shaped in a manner other than those shown. The same applies to the plurality of adsorption regions of the second adsorption surface 21s.

[0111] Figure 10A as well as Figure 10B 1 is a schematic top view of the first clamp 11. Figure 10A as well as Figure 10B The following example is shown: the first clamp 11 is a vacuum clamp, and the first adsorption surface 11s includes a plurality of adsorption areas. A plurality of suction ports 11p for sucking gas are opened on the first adsorption surface 11s. Figure 10A In the example shown, the plurality of suction ports 11p are arranged on a plurality of straight lines extending radially from the center of the first adsorption surface 11s. Figure 10B In the illustrated example, the plurality of suction ports 11 p are arranged on a plurality of straight lines that cross the first suction surface 11 s and are parallel to each other. Figure 10B An example is shown in which the plurality of suction ports 11 p are arranged at equal intervals in the vertical and horizontal directions.

[0112] In the case where the first clamp 11 or the second clamp 21 is a vacuum clamp, it is sufficient to set one or more suction ports 11p and valves 11v in each adsorption area. In the case where the first clamp 11 or the second clamp 21 is an electrostatic clamp, it is sufficient to set multiple electrodes corresponding to multiple adsorption areas one to one. If the valve 11v is opened, the one or more suction ports 11p opened in the adsorption area corresponding to the valve 11v start to suck gas. If the valve 11v is closed, the one or more suction ports 11p opened in the adsorption area corresponding to the valve 11v stop sucking gas. If voltage starts to be applied to the electrode, the adsorption area corresponding to the electrode starts to generate an electric attraction force. If the voltage is stopped from being applied to the electrode, the adsorption area corresponding to the electrode stops generating an electric attraction force. As a result, multiple adsorption areas generate and stop generating adsorption forces independently of each other.

[0113] Next, the first joining module 2b1 will be described.

[0114] Figure 11 This is a diagram of the first joining module 2b1 viewed horizontally from the X direction. Figure 12 FIG is a top view of the first bonding module 2b1. Figure 11 as well as Figure 12 As shown, the first bonding module 2b1 includes a first worktable 13 that can move parallel to the Z direction relative to the base 20 together with the first clamp 11. The first bonding module 2b1 also includes a pair of support shafts 14 that support the first clamp 11 via the first worktable 13, a pair of support bases 15, and a first frame 19. The first worktable 13 can also be a horizontal flat plate.

[0115] The first frame 19 includes a pair of first side frames 19 s extending upward from the upper surface of the pedestal 20 , and a first upper frame 19 u extending from one first side frame 19 s to the other first side frame 19 s while being separated upward from the pedestal 20 . Figure 11 The example of the gate-shaped first frame 19 is shown. In this example, the first upper frame 19u connects the upper ends of the pair of first side frames 19s.

[0116] A pair of first side frames 19s are fixed to the pedestal 20. A first upper frame 19u is fixed to the pair of first side frames 19s. The pair of first side frames 19s face each other in the Y direction with a gap therebetween. The first upper frame 19u faces the upper surface of the pedestal 20 in the Z direction with a gap therebetween. The pair of first side frames 19s are arranged on both sides of the first clamp 11, the first workbench 13, the pair of support shafts 14, and the pair of support bases 15 in the Y direction. When viewed from above, the first upper frame 19u is arranged above the first clamp 11, the first workbench 13, the pair of support shafts 14, and the pair of support bases 15 in a manner overlapping with the first clamp 11, the first workbench 13, the pair of support shafts 14, and the pair of support bases 15.

[0117] The first fixture 11, the first workbench 13, the pair of support shafts 14, and the pair of support bases 15 are supported by the first frame 19 so as to be separated upward from the base 20. The pair of support bases 15 are arranged between the pair of first side frames 19s in the Y direction. The pair of support shafts 14 are arranged between the pair of support bases 15 in the Y direction. The first workbench 13 is arranged between the pair of support shafts 14 in the Y direction. The pair of support bases 15 are supported by the pair of first side frames 19s. The pair of support shafts 14 are supported by the pair of support bases 15 in a horizontal position such that the center lines of the pair of support shafts 14 are parallel to the Y direction. The first workbench 13 is supported by the pair of support shafts 14 in a position such that the center line of the pair of support shafts 14 is vertical.

[0118] The first joining module 2b1 includes a plurality of linear guides 17 for linearly guiding the pair of support bases 15 in the Z direction relative to the first frame 19. At least one linear guide 17 is provided for each support base 15. Figure 12 The example shown here shows two linear guides 17 per support base 15. Each linear guide 17 includes a rail 17L extending linearly in the longitudinal direction; a slider 17b that moves along the rail 17L in the longitudinal direction; and a plurality of balls interposed between the rail 17L and the slider 17b. The rail 17L is fixed to the first side frame 19s in a position parallel to the Z direction. The slider 17b is fixed to the support base 15.

[0119] The actuator mechanism AC includes at least one Z actuator 18 that moves the first jig 11 and the second jig 21 relative to each other in the Z direction. Figure 11 In the example shown below, at least one Z actuator 18 moves the pair of support bases 15 in the Z direction, thereby moving the first substrate W1 held by the first clamp 11 in the Z direction. At least one Z actuator 18 may be provided on only one support base 15 or on each support base 15. Figure 11 An example is shown in which one Z actuator 18 is provided for each supporting base 15 .

[0120] An actuator is a device that converts electrical, fluid, magnetic, thermal, or chemical energy into mechanical work. Actuators include electric motors (rotary motors), linear motors, cylinders, and other devices. The Z actuator 18 can be an electric motor, a linear motor, or other components. Figure 11 as well as Figure 12 An example is shown in which the Z actuator 18 is an electric motor.

[0121] The power of the Z actuator 18 is transmitted to the first clamp 11 via a transmission mechanism including a driver and a follower. Figure 11 as well as Figure 12 In the example shown, the driving element is a ball screw 18s and the driven element is a ball nut 18n. However, the driving element and the driven element may be components other than the ball screw 18s and the ball nut 18n, such as a rack and a pinion.

[0122] like Figure 12 As shown, the ball screw 18s and the ball nut 18n are arranged between the first side frame 19s and the support base 15. The ball nut 18n is fixed to the support base 15. The ball nut 18n is connected to the ball screw 18s via a plurality of balls. The two ball screws 18s are respectively arranged at two different positions with an angle of 180 degrees around the center line 11c of the first clamp 11. The center line 18c of the two ball screws 18s extends vertically within a plane, which is a plane extending in the Y direction and the Z direction.

[0123] When an electric motor, an example of the Z actuator 18, rotates the ball screw 18s, the ball nut 18n moves along the ball screw 18s in the Z direction. The ball nut 18n and the support base 15 move in the Z direction by an amount corresponding to the rotation angle of the Z actuator 18. If the two Z actuators 18 rotate at the same angle and in the same direction, the two ball nuts 18n move the same amount in the Z direction. This causes the first substrate W1 held by the first clamp 11 to rise or fall in the Z direction.

[0124] The actuator mechanism AC includes a first rotation motor 12 that rotates the first clamp 11 relative to the first workbench 13 around the center line 11c of the first clamp 11, which corresponds to the rotation axis. The first rotation motor 12 is an electric motor. The first rotation motor 12 is arranged between the first clamp 11 and the first workbench 13. The first rotation motor 12 is connected to the first clamp 11 and the first workbench 13. The first substrate W1 is held by the first clamp 11 so that the center of the first substrate W1 is located on the center line 11c of the first clamp 11. If the first rotation motor 12 rotates in this state, the first substrate W1 and the first clamp 11 rotate relative to the first workbench 13 in the same direction and at the same angle as the first rotation motor 12.

[0125] The actuator mechanism AC includes at least one flip actuator 16 that rotates the first clamp 11 about a horizontal flip center 16 c. Figure 11 as well as Figure 12 The example in which the tilt actuator 16 is disposed within the support shaft 14 is shown. In this example, the tilt actuator 16 is disposed above the base 20 so as to overlap with the base 20 when viewed from above. The tilt actuator 16 may also be disposed outside the support shaft 14. A single tilt actuator 16 may be provided on only one support shaft 14, or one may be provided on each support shaft 14. Figure 11 as well as Figure 12 An example of the latter is shown.

[0126] The flip actuator 16 is an electric motor. The flip actuator 16 may also be an actuator other than an electric motor. Figure 11 as well as Figure 12 In the example shown, the flip actuator 16 rotates the first table 13 around the center line of the pair of support shafts 14, thereby rotating the first fixture 11. The center line of the pair of support shafts 14 corresponds to the flip center 16c. Therefore, the first fixture 11 and the first table 13 rotate around the horizontal flip center 16c extending in the Y direction. The flip center 16c is the center line 18c passing through the two ball screws 18s (see Figure 12 ). When the flip actuator 16 rotates 180 degrees, the first clamp 11 and the first worktable 13 rotate 180 degrees and face downward. As a result, the first substrate W1 held by the first clamp 11 is flipped.

[0127] The first worktable 13 may be fixed to the pair of support shafts 14, or it may be rotatable relative to the pair of support shafts 14 about the flip center 16c. In the former case, the flip actuator 16 rotates the pair of support shafts 14 relative to the pair of support bases 15, thereby rotating the first worktable 13 and the first fixture 11 about the flip center 16c. In the latter case, the flip actuator 16 rotates the first worktable 13 relative to the pair of support shafts 14, thereby rotating the first fixture 11 about the flip center 16c.

[0128] The first fixture 11 and the first worktable 13 are movable in the Z direction relative to the pedestal 20 and the first frame 19. The range of movement of the first fixture 11 and the first worktable 13 in the Z direction includes a position where a rotating object, such as the first worktable 13, will not collide with the pedestal 20 and the first frame 19, even if the first fixture 11 and the first worktable 13 are rotated 180 degrees about the flip center 16c. The size of the first worktable 13 and the first frame 19 is set so that a rotating object will not collide with the pedestal 20 and the first frame 19, even if the first fixture 11 and the first worktable 13 are rotated to any position in the Z direction.

[0129] The flip actuator 16 is part of the flip unit. While the first substrate W1 is held by the first clamp 11, the flip actuator 16 rotates the first clamp 11 180 degrees about the flip center 16c, thereby flipping the first substrate W1. As will be described later, the first clamp 11 holds the first substrate W1 while it is bonded to the second substrate W2. Therefore, the first substrate W1 is held by the first clamp 11 before flipping and is also held by the first clamp 11 while bonded to the second substrate W2.

[0130] The flip actuator 16 is an example of a posture changing actuator that changes the posture of the substrate W. The two Z actuators 18 described above are both examples of posture changing actuators. If the two ball nuts 18n of the two Z actuators 18 are arranged at different heights within the range of mechanical play in the mechanism supporting the first clamp 11, the centerline 11c of the first clamp 11 tilts in the Y direction. As a result, the posture of the first substrate W1 held by the first clamp 11 changes.

[0131] Next, the first fixed reference member 31r will be described.

[0132] Figure 13 FIG. 1 is a top view of the first workbench 13 . Figure 14 For Figure 13 The first workbench 13 is viewed horizontally in the direction of arrow XIV. Figure 13 as well as Figure 14 As shown, the first bonding module 2b1 includes a first fixed reference member 31r that serves as an indirect reference for aligning the first substrate W1. The first fixed reference member 31r includes: at least one first reference mark 31m that serves as an indirect reference for aligning the first substrate W1; and a first display plate 31d marked with the at least one first reference mark 31m.

[0133] Figure 13An example is shown in which two first reference marks 31m of equal shape and size are provided. In this example, the first reference mark 31m is in the shape of a cross. The first reference mark 31m may also have a shape other than a cross. The first reference mark 31m may be formed on the first display plate 31d by photolithography or by methods other than photolithography, such as laser marking.

[0134] exist Figure 13 In the example shown, the first display panel 31d is a horizontal rectangular flat plate extending in the Y direction, and two first reference marks 31m are marked on each end of the first display panel 31d in the Y direction. The two long sides of the first display panel 31d extend in the Y direction, and the two short sides of the first display panel 31d extend in the X direction. Figure 14 As shown, in this example, the first display panel 31d is supported by the first workbench 13 via two first support blocks 31b. The upper and lower surfaces of the first display panel 31d are two parallel horizontal planes. The lower surface of the first display panel 31d faces the horizontal and flat upper surface of the first workbench 13 in the Z direction, with a gap therebetween. The lower surface of the first display panel 31d may also contact the upper surface of the first workbench 13.

[0135] The shape and arrangement of the first display plate 31d and the number and arrangement of the first reference marks 31m are not limited to Figure 13 as well as Figure 14 The example shown. For example, the first display panel 31d can also be rotated 90 degrees in the horizontal plane so that the long side of the first display panel 31d extends in the X direction. The first display panel 31d may include a horizontal rectangular vertical panel extending in the Y direction and a horizontal rectangular horizontal panel extending in the X direction. The vertical panel and the horizontal panel may be in contact with each other or separated from each other. In the case where the first display panel 31d includes a vertical panel and a horizontal panel, these first reference marks 31m may be arranged in such a manner that three or more first reference marks 31m are arranged in the X direction and the Y direction. For example, the second first reference mark 31m may be arranged on a horizontal straight line passing through the first first reference mark 31m and parallel to the X direction, and the third first reference mark 31m may be arranged on a horizontal straight line passing through the first first reference mark 31m and parallel to the Y direction.

[0136] When setting the first fixed point 31p and the first fixed line 31L, which serve as indirect references when aligning the first substrate W1, at least one first reference mark 31m is used. The first fixed point 31p and the first fixed line 31L are virtual points and lines. Figure 13In the example shown, a horizontal straight line passing through the centers of gravity of two cross-shaped first reference marks 31m is set as the first fixing line 31L of the first workbench 13. The first fixing point 31p of the first workbench 13 may be the center of gravity of one first reference mark 31m or any point on the first fixing line 31L, or may be any other point.

[0137] like Figure 13 As shown, the first fixed reference member 31r is arranged above the first workbench 13 in such a manner that the first fixed reference member 31r overlaps with the first workbench 13 when viewed from above. The first fixed reference member 31r is fixed to the first workbench 13. The upper end of the first fixed reference member 31r is arranged below the first substrate W1 on the first clamp 11. In a state where the first clamp 11 holds the first substrate W1, when viewed from the direction of the center line 11c of the first clamp 11, the first fixed reference member 31r does not overlap with the first substrate W1 held by the first clamp 11. Therefore, if the first workbench 13 is observed from the direction of the center line 11c of the first clamp 11 in this state, the camera can be used to capture not only the first reference mark 31m but also the first alignment mark AM1 of the first substrate W1.

[0138] As described later, at least one first alignment mark AM1 of the first substrate W1 held by the first clamp 11 is photographed by a camera. The camera also photographs at least one first reference mark 31m of the first fixed reference part 31r. The position and angle of the first substrate W1 in the horizontal plane are determined based on the image of the at least one first alignment mark AM1 photographed by the camera. The position and angle of the first fixed reference part 31r in the horizontal plane are also determined based on the image of the at least one first reference mark 31m photographed by the camera. Furthermore, the relative position and relative angle of the first substrate W1 and the first fixed reference part 31r are also determined based on the images of the first alignment mark AM1 and the first reference mark 31m. Therefore, as long as the position and angle of the first fixed reference part 31r are known, the position and angle of the first substrate W1 held by the first clamp 11 can also be known. This information is stored in the control device 3 (refer to Figure 1 ).

[0139] Next, the second joining module 2b2 will be described.

[0140] Figure 15 This is a diagram of the second joining module 2b2 viewed horizontally from the X direction. Figure 16 To enlarge Figure 15 Part of the diagram. Figure 17 FIG. 2 is a top view of the second bonding module 2b2. Figure 18 This is a diagram of the second bonding module 2b2 viewed horizontally from the Y direction.

[0141] like Figures 15 to 17As shown, the second bonding module 2b2 includes a second worktable 23 that can move parallel to the base 20 in the X and Y directions together with the second fixture 21. The second worktable 23 includes an upper worktable 23u disposed between the second fixture 21 and the base 20; and a lower worktable 23L disposed between the upper worktable 23u and the base 20. Figures 15 to 17 In the example shown below, the upper table 23u is a Y-table that can move parallel to the Y direction relative to the table 20, and the lower table 23L is an X-table that can move parallel to the X direction relative to the table 20. The lower table 23L is larger than the upper table 23u. One or both of the upper table 23u and the lower table 23L can be horizontal flat plates.

[0142] The second bonding module 2 b 2 includes at least one linear guide 26 that linearly guides the lower table 23L relative to the stage 20 in the X direction. Figure 15 The example in which two linear guides 26 are provided is shown. The two linear guides 26 are arranged on the base 20. The lower table 23L is arranged on the two linear guides 26. Figure 16 As shown, the linear guide 26 includes a rail 26L extending linearly in the longitudinal direction; a slider 26b that moves along the rail 26L in the longitudinal direction of the rail 26L; and a plurality of balls interposed between the rail 26L and the slider 26b. The rail 26L is fixed to the base 20 in a position parallel to the X-direction. The slider 26b is fixed to the lower table 23L.

[0143] The actuator mechanism AC includes at least one X actuator 27 that moves the first jig 11 and the second jig 21 relative to each other in the X direction. Figure 15 The following example is shown: at least one X actuator 27 moves the lower table 23L in the X direction, thereby moving the second substrate W2 held by the second clamp 21 in the X direction. In this example, two X actuators 27 are provided, and each X actuator 27 is a linear motor. Figure 16 As shown, the linear motor includes a fixed magnet 27f extending linearly in the longitudinal direction, and a movable magnet 27m that moves along the fixed magnet 27f in the longitudinal direction of the fixed magnet 27f. The fixed magnet 27f is fixed to the base 20 in a position parallel to the X direction. The movable magnet 27m is fixed to the lower table 23L.

[0144] like Figure 17 as well as Figure 18 As shown, the second joining module 2b2 includes at least one linear guide 24 that linearly guides the upper table 23u in the Y direction relative to the lower table 23L. Figure 17An example is shown in which two linear guides 24 are installed. The two linear guides 24 are arranged on the lower table 23L. The upper table 23u is also arranged on the two linear guides 24. The linear guides 24 include a rail 24L extending linearly in the longitudinal direction; a slider 24b that moves along the rail 24L in the longitudinal direction of the rail 24L; and a plurality of balls interposed between the rail 24L and the slider 24b. The rail 24L is fixed to the lower table 23L in a position parallel to the Y direction. The slider 24b is fixed to the upper table 23u.

[0145] The actuator mechanism AC includes at least one Y actuator 25 that moves the first jig 11 and the second jig 21 relative to each other in the Y direction. Figure 18 The following example is shown: at least one Y actuator 25 moves the upper worktable 23u in the Y direction, thereby moving the second substrate W2 held by the second clamp 21 in the Y direction. In this example, two Y actuators 25 are provided, each of which is a linear motor. The linear motor includes: a fixed magnet 25f extending linearly in the longitudinal direction; and a movable magnet 25m that moves along the fixed magnet 25f in the longitudinal direction of the fixed magnet 25f. The fixed magnet 25f is fixed to the lower worktable 23L in a posture parallel to the Y direction. The movable magnet 25m is fixed to the upper worktable 23u.

[0146] The X actuator 27, the Y actuator 25, and the Z actuator 18 are examples of parallel translation actuators that move at least one of the first jig 11 and the second jig 21 in parallel. The Y actuator 25 is an example of a horizontal actuator that moves at least one of the first jig 11 and the second jig 21 horizontally. The X actuator 27 is also an example of a horizontal actuator. The Z actuator 18 is an example of a vertical translation actuator that moves at least one of the first jig 11 and the second jig 21 vertically.

[0147] The X actuator 27 makes the second clamp 21 in the engagement position ( Figure 31E Position shown) and shooting position ( Figure 31G The first substrate W1 held by the first clamp 11 and the second substrate W2 held by the second clamp 21 are joined at the bonding position. The imaging position is where the camera images the first substrate W1 and the second substrate W2 held by the second clamp 21.

[0148] The imaging positions may also be a range extending in at least one of the X and Y directions. For example, the imaging positions may include: a pre-joining imaging position for the first narrow field of view camera 41n and the first wide field of view camera 41w, described later, to image the second substrate W2 held by the second clamp 21; and a post-joining imaging position for the inspection camera 43, described later, to image the first substrate W1 and the second substrate W2 held by the second clamp 21 after the first substrate W1 and the second substrate W2 are joined.

[0149] The actuator mechanism AC includes a second rotation motor 22 that rotates the second clamp 21 relative to the upper workbench 23u around the center line 21c of the second clamp 21, which corresponds to the rotation axis. The second rotation motor 22 is an electric motor. The second rotation motor 22 is arranged between the second clamp 21 and the upper workbench 23u. The second rotation motor 22 is connected to the second clamp 21 and the upper workbench 23u. The second substrate W2 is held by the second clamp 21 so that the center of the second substrate W2 is located on the center line 21c of the second clamp 21. If the second rotation motor 22 rotates in this state, the second substrate W2 and the second clamp 21 rotate relative to the upper workbench 23u in the same direction and at the same angle as the second rotation motor 22.

[0150] like Figure 15 As shown, the second joining module 2b2 includes a second frame 28 that defines a space for the second fixture 21 and the second worktable 23 to enter and exit in the X direction. The second frame 28 includes a pair of second side frames 28s extending upward from the upper surface of the base 20, and a second upper frame 28u extending from one second side frame 28s toward the other second side frame 28s while being separated upward from the base 20. Figure 15 The example of the gate-shaped second frame 28 is shown. In this example, the second upper frame 28u connects the upper ends of the pair of second side frames 28s.

[0151] The pair of second side frames 28s are fixed to the pedestal 20. The second upper frame 28u is fixed to the pair of second side frames 28s. The pair of second side frames 28s face each other in the Y direction with a gap therebetween. The second upper frame 28u faces the upper surface of the pedestal 20 in the Z direction with a gap therebetween. The pair of second side frames 28s are arranged on either side of the second jig 21 and the second worktable 23 in the Y direction. The second upper frame 28u is arranged above the second jig 21 and the second worktable 23 so as to overlap with them when viewed from above.

[0152] The second frame 28 is separated from the first frame 19 in the X direction (see Figure 7). When the X actuator 27 moves the lower worktable 23L in the X direction, the second jig 21 and the second worktable 23 can enter and exit the space inside the second frame 28 in the X direction. Similarly, the second jig 21 and the second worktable 23 can enter and exit the space inside the first frame 19 in the X direction. The second jig 21 and the second worktable 23 can enter and exit between the first worktable 13 and the base 20. When the first jig 11 is facing downward, the second jig 21 and the second worktable 23 can enter and exit between the first jig 11 and the base 20.

[0153] When the second jig 21 and the second work table 23 are positioned between the pair of second side frames 28s, even if the Y actuator 25 moves the upper work table 23u in the Y direction relative to the lower work table 23L, the second jig 21 and the upper work table 23u will not collide with the second frame 28. Similarly, when the second jig 21 and the second work table 23 are positioned between the pair of first side frames 19s, even if the Y actuator 25 moves the upper work table 23u in the Y direction relative to the lower work table 23L, the second jig 21 and the upper work table 23u will not collide with the first frame 19.

[0154] The bonding unit 2b may also include multiple distance meters that measure the vertical distance to the bonding surface WA1 of the first substrate W1 held downward by the first clamp 11. The distance meters are non-contact distance meters that measure distances without making contact with an object such as the first substrate W1. The distance meters may be optical distance meters such as laser distance meters, or other distance meters.

[0155] The multiple distance meters are positioned below the first substrate W1, which is held downward by the first fixture 11. The multiple distance meters can be fixed to the upper worktable 23u. In this case, the multiple distance meters move horizontally in the same direction, at the same speed, and by the same amount as the upper worktable 23u. The multiple distance meters measure vertical distances to multiple positions within the bonding surface WA1 of the first substrate W1, which is facing downward. This allows the flatness of the bonding surface WA1 of the first substrate W1 to be measured.

[0156] If the bonding surface WA1 of the first substrate W1 is horizontal before flipping, the flip actuator 16 can be accurately rotated 180 degrees, and the bonding surface WA1 of the first substrate W1 facing downward will be horizontal. This can be confirmed by measuring the distance from multiple distance meters to the bonding surface WA1 of the first substrate W1 facing downward. If the bonding surface WA1 of the first substrate W1 is not horizontal, the flip actuator 16 can be rotated until the bonding surface WA1 of the first substrate W1 is horizontal. This improves the parallelism of the first substrate W1 and the second substrate W2.

[0157] Next, the second reference mark 32m will be described.

[0158] Figure 19 FIG. 2 is a top view of the second workbench 23 . Figure 20 For Figure 19 The second workbench 23 is viewed horizontally in the direction of arrow XX. Figure 19 as well as Figure 20 As shown, the second bonding module 2b2 includes a second fixed reference member 32r that serves as an indirect reference for aligning the second substrate W2. The second fixed reference member 32r includes: at least one second reference mark 32m that serves as an indirect reference for aligning the second substrate W2; and a second display plate 32d marked with at least one second reference mark 32m.

[0159] Figure 19 An example is shown in which two second reference marks 32m of equal shape and size are provided. In this example, second reference marks 32m are rectangular (including four L-shaped figures). Second reference marks 32m may also have shapes other than rectangles. Second reference marks 32m may be formed on second display plate 32d by photolithography or by methods other than photolithography, such as laser marking.

[0160] exist Figure 19 In the example shown, the second display panel 32d is a horizontal rectangular flat plate extending in the Y direction. Two second reference marks 32m of equal shape and size are marked at each end of the second display panel 32d in the Y direction. The two long sides of the second display panel 32d extend in the Y direction, and the two short sides of the second display panel 32d extend in the X direction. Figure 20 As shown, in this example, the second display panel 32d is supported by the upper worktable 23u via two second support blocks 32b. The upper and lower surfaces of the second display panel 32d are two parallel horizontal planes. The lower surface of the second display panel 32d faces the horizontal and flat upper surface of the upper worktable 23u in the Z direction, with a gap therebetween. The lower surface of the second display panel 32d can contact the upper surface of the upper worktable 23u.

[0161] When setting the second fixed point 32p and the second fixed line 32L, which serve as indirect references for aligning the second substrate W2, at least one second reference mark 32m is used. The second fixed point 32p and the second fixed line 32L are virtual points and lines. Figure 19 In the example shown, a horizontal line passing through the centers of gravity of two rectangular second reference marks 32m is set as second fixing line 32L of upper table 23u. Second fixing point 32p of upper table 23u can be the center of gravity of one second reference mark 32m, any point on second fixing line 32L, or any other point.

[0162] like Figure 19 As shown, the second fixed reference member 32r is arranged above the upper workbench 23u in such a manner that the second fixed reference member 32r overlaps with the upper workbench 23u when viewed from above. The second fixed reference member 32r is fixed to the upper workbench 23u. The upper end of the second fixed reference member 32r is arranged below the second substrate W2 on the second clamp 21. In a state where the second clamp 21 holds the second substrate W2, when viewed from the direction of the center line 21c of the second clamp 21, the second fixed reference member 32r does not overlap with the second substrate W2 held by the second clamp 21. Therefore, if the upper workbench 23u is observed from the direction of the center line 21c of the second clamp 21 in this state, the camera can not only capture the second reference mark 32m, but also the second alignment mark AM2 of the second substrate W2.

[0163] As described later, at least one second alignment mark AM2 of the second substrate W2 held by the second clamp 21 is photographed by the camera. The camera also photographs at least one second reference mark 32m of the second fixed reference part 32r. The position and angle of the second substrate W2 in the horizontal plane are determined based on the image of the at least one second alignment mark AM2 photographed by the camera. The position and angle of the second fixed reference part 32r in the horizontal plane are also determined based on the image of the at least one second reference mark 32m photographed by the camera. Furthermore, the relative position and angle of the second substrate W2 and the second fixed reference part 32r are also determined based on the image of the second alignment mark AM2 and the second reference mark 32m. Therefore, as long as the position and angle of the second fixed reference part 32r are known, the position and angle of the second substrate W2 held by the second clamp 21 can also be known. This information is stored in the control device 3 (refer to Figure 1 ).

[0164] Next, the camera included in the joining unit 2b will be described.

[0165] Figure 21 2b is a top view of the bonding unit 2b. Figure 22 This is a diagram of the second camera 42 that photographs the second substrate W2 as viewed horizontally from the Y direction. Figure 23 This is a diagram showing the first camera 41 that photographs the first substrate W1 as viewed horizontally from the Y direction. Figure 24 This is a diagram of the alignment camera 45 that photographs the first fixed reference member 31 r and the second fixed reference member 32 r as viewed horizontally from the Y direction. Figure 25 For Figure 24 The arrow XXV is shown in the direction of the horizontal viewing of the image with the camera 45 aligned therewith.

[0166] like Figure 21 as well as Figure 22As shown, the bonding unit 2b includes at least one first camera 41 for photographing the first substrate W1 held by the first clamp 11 and the first fixed reference member 31r; and at least one second camera 42 for photographing the second substrate W2 held by the second clamp 21 and the second fixed reference member 32r. The bonding unit 2b also includes an inspection camera 43 for photographing the first substrate W1 and the second substrate W2 held by the second clamp 21 after bonding. Figure 21 as well as Figure 22 The example shows two first cameras 41 and two second cameras 42. The two first cameras 41 are a first narrow field of view camera 41n and a first wide field of view camera 41w. The two second cameras 42 are a second narrow field of view camera 42n and a second wide field of view camera 42w.

[0167] The first narrow field of view camera 41n and the first wide field of view camera 41w are fixed to the upper stage 23u of the second stage 23. The first narrow field of view camera 41n and the first wide field of view camera 41w move in the X and Y directions at the same speed and distance as the upper stage 23u. The second stage 23 is moved by at least one of the X actuator 27 and the Y actuator 25, thereby adjusting the positions of the first narrow field of view camera 41n and the first wide field of view camera 41w relative to the first stage 13 in the X and Y directions.

[0168] The second narrow field of view camera 42n, the second wide field of view camera 42w, and the inspection camera 43 are fixed to the second frame 28 via a bracket 44. The second narrow field of view camera 42n, the second wide field of view camera 42w, and the inspection camera 43 are arranged above the stage 20 so as to overlap with the stage 20 when viewed from above. The inspection camera 43 is part of the inspection unit. The second substrate W2 is held by the second clamp 21 before being bonded to the first substrate W1. The second substrate W2 is also held by the second clamp 21 while the inspection camera 43 is capturing images of the bonded first and second substrates W1 and W2.

[0169] Figure 21 The following example is shown: the second narrow field camera 42n, the second wide field camera 42w, and the inspection camera 43 are inserted into three through holes 44h that penetrate the bracket 44 in the Z direction, and are arranged on the first jig 11 side relative to the second frame 28 ( Figure 21 The second stage 23 is moved by at least one of the X actuator 27 and the Y actuator 25, thereby adjusting the positions of the second narrow field camera 42n, the second wide field camera 42w, and the inspection camera 43 relative to the second stage 23 in the X and Y directions.

[0170] A narrow field of view camera has a narrower field of view than a wide field of view camera. The imaging range of the first narrow field of view camera 41n can be a portion of the imaging range of the first wide field of view camera 41w, or it can be outside the imaging range of the first wide field of view camera 41w. The same applies to the second narrow field of view camera 42n and the second wide field of view camera 42w. The resolution of the narrow field of view camera can be the same as or different from that of the wide field of view camera. The narrow field of view camera and the wide field of view camera can be two cameras with lenses of different magnifications, but with the same specifications other than the imaging magnification, such as resolution.

[0171] Control device 3 (refer to Figure 1 ) receives electronic data of a static or dynamic image generated by the first wide-field-of-view camera 41w. The control device 3 analyzes and determines the image based on a program stored in the memory 3c. If the analysis results in a determination that the first alignment mark AM1 is included in the image, the control device 3 can store the position of the first alignment mark AM1. This allows the imaging range of the first narrow-field-of-view camera 41n to be quickly moved to the area where the first alignment mark AM1 is located. Even if the first narrow-field-of-view camera 41n fails to find the first alignment mark AM1, that is, even if the imaging range of the first narrow-field-of-view camera 41n is moved to an area where the first alignment mark AM1 is not located, the imaging range of the first narrow-field-of-view camera 41n can be quickly returned to the area where the first alignment mark AM1 is located.

[0172] Similarly, the control device 3 can store the position of the first fiducial mark 31m when it determines that the image generated by the first wide-field-of-view camera 41w contains the first fiducial mark 31m. Similarly, the control device 3 can store the position of the second alignment mark AM2 and the second fiducial mark 32m when it determines that the image generated by the second wide-field-of-view camera 42w contains at least one of the second alignment mark AM2 and the second fiducial mark 32m. This can shorten the imaging time of the first narrow-field-of-view camera 41n and the second narrow-field-of-view camera 42n.

[0173] The lenses of the first narrow field of view camera 41n and the first wide field of view camera 41w are directed upward. Figure 23As shown, with the first substrate W1 held by the first clamp 11, the first worktable 13 rotates 180 degrees about the flip center 16c. The first narrow field of view camera 41n and the first wide field of view camera 41w capture images of the downward-facing first substrate W1 and the downward-facing first fixed reference member 31r. While the first narrow field of view cameras 41n and 41w capture images, at least one of the X actuator 27 and the Y actuator 25 moves the first narrow field of view cameras 41n and 41w in at least one of the X and Y directions, allowing the first narrow field of view cameras 41n and 41w to capture images of the entire range to be captured. This captures the first alignment mark AM1 of the first substrate W1 and the first reference mark 31m of the first fixed reference member 31r.

[0174] The lenses of the second narrow field of view camera 42n and the second wide field of view camera 42w are oriented downward. Figure 22 As shown, with the second substrate W2 held by the second clamp 21, at least one of the second substrate W2 and the second fixed reference member 32r is positioned within the imageable range of the second narrow field of view camera 42n and the second wide field of view camera 42w. In this state, the second narrow field of view camera 42n and the second wide field of view camera 42w capture images of the second substrate W2 and the second fixed reference member 32r facing upward. While the second narrow field of view cameras 42n and the second wide field of view camera 42w capture images, at least one of the X actuator 27 and the Y actuator 25 moves the second substrate W2 and the second fixed reference member 32r in at least one of the X and Y directions. This allows the second narrow field of view cameras 42n and the second wide field of view camera 42w to capture images of the entire image range, capturing images of the second alignment mark AM2 on the second substrate W2 and the second reference mark 32m on the second fixed reference member 32r.

[0175] Similar to the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w, the lens of the inspection camera 43 faces downward. When the inspection camera 43 is capturing images, the first and second substrates W1, W2 are held by the second clamp 21, and are positioned within the imageable range of the inspection camera 43. In this position, the inspection camera 43 captures the first substrate W1 facing downward and the second substrate W2 facing upward. During the capture, at least one of the X actuator 27 and the Y actuator 25 moves the first and second substrates W1, W2 in at least one of the X and Y directions. This allows the inspection camera 43 to capture the entire image.

[0176] First narrow field of view camera 41n, first wide field of view camera 41w, second narrow field of view camera 42n, and second wide field of view camera 42w are visible light cameras that convert visible light into electrical signals, thereby generating static or dynamic electronic data. Inspection camera 43 is an infrared camera that converts infrared light into electrical signals, thereby generating static or dynamic electronic data. Visible light cameras can produce clearer images than infrared cameras. However, if there is an object impenetrable to visible light between the visible light camera and the subject, the subject cannot be imaged. Even if there is an object impenetrable to visible light between the visible light camera and the subject, the infrared camera can still image the subject through the object, as long as the object is made of an infrared-transmissive material such as silicon.

[0177] When the inspection camera 43 photographs the first substrate W1 and the second substrate W2, the first substrate W1 and the second substrate W2 are superimposed on each other with the first substrate W1 facing downward and the second substrate W2 facing upward. Even if the first substrate W1 and the second substrate W2 in this state are photographed from above using a visible light camera, the first alignment mark AM1 of the first substrate W1 and the second alignment mark AM2 of the second substrate W2 will not be captured in the photographed image. The inspection camera 43 is an infrared camera. At least one first alignment mark AM1 of the first substrate W1 is separated from the base material WD1 of the first substrate W1 (refer to FIG. 1 ). Figure 3 ) is photographed by the inspection camera 43. At least one second alignment mark AM2 of the second substrate W2 is photographed via the first substrate W1 by the inspection camera 43. Thus, in a state where the first substrate W1 and the second substrate W2 are bonded, the first alignment mark AM1 and the second alignment mark AM2 are photographed by the inspection camera 43.

[0178] like Figure 24 as well as Figure 25 As shown, the joining unit 2b includes, in addition to the first camera 41, etc., at least one alignment camera 45, which photographs the first fixed reference member 31r and the second fixed reference member 32r when they are facing each other in the Z direction with a gap between them. Figure 24 as well as Figure 25 An example is shown in which two aiming cameras 45 are provided. Figure 24 as well as Figure 25 In the embodiment, the lower surface of the first worktable 13 faces upward. The alignment camera 45 protrudes from the lower surface of the first worktable 13. The alignment camera 45 is fixed to the first worktable 13. The alignment camera 45 moves in the Z direction together with the first worktable 13 and rotates around the inversion center 16c together with the first worktable 13.

[0179] At least a portion of the alignment camera 45 is disposed directly below the first fixed reference member 31r (at Figure 24 as well as Figure 25 (In the state shown, it is arranged directly above the first fixed reference member 31r). The lens of the alignment camera 45 directly faces the first fixed reference member 31r in the Z direction. Figure 25 The example in which alignment camera 45 is inserted into through-hole 13h extending through first table 13 in the Z direction is shown. The placement of alignment camera 45 is not limited to this, as long as alignment camera 45 and first fixed reference member 31r are directly facing each other in the Z direction. In any case, first reference mark 31m is positioned within the range that alignment camera 45 can capture. A single alignment camera 45 can capture two or more first reference marks 31m.

[0180] When performing alignment adjustment to minimize the positional deviation of the first substrate W1 and the second substrate W2, as shown in FIG. Figure 24 as well as Figure 25 As shown, the first worktable 13 is rotated 180 degrees about the turning center 16c, so that the first substrate W1 held by the first clamp 11 faces downward. At this time, the first fixed reference member 31r also faces downward. If the second clamp 21 is positioned below the first clamp 11 so that the first substrate W1 held downward by the first clamp 11 and the second substrate W2 held upward by the second clamp 21 face each other directly in the Z direction, the first fixed reference member 31r and the second fixed reference member 32r face each other directly in the Z direction with a gap therebetween. In this state, the alignment camera 45 captures the first fixed reference member 31r and the second fixed reference member 32r.

[0181] The alignment camera 45 is a visible light camera. When the alignment camera 45 images the first fixed reference member 31r and the second fixed reference member 32r, the first fixed reference member 31r, which acts as a mask, is positioned between the alignment camera 45 and the second fixed reference member 32r. The first display plate 31d of the first fixed reference member 31r is a transparent plate that is transparent to visible light. The second display plate 32d of the second fixed reference member 32r is also a transparent plate. The alignment camera 45 simultaneously images both the first reference mark 31m and the second reference mark 32m while the first fixed reference member 31r and the second fixed reference member 32r are facing each other directly in the Z direction with a gap between them. As long as the alignment camera 45 can image the second reference mark 32m in this state, the second display plate 32d of the second fixed reference member 32r may also be a non-transparent plate that is not transparent to visible light.

[0182] After the first camera 41 captures the first alignment mark AM1 and the first reference mark 31m, not only can the position and angle of the first substrate W1 within the horizontal plane be determined, but also the relative position and angle between the first substrate W1 and the first fixed reference member 31r can be determined. Similarly, after the second camera 42 captures the second alignment mark AM2 and the second reference mark 32m, not only can the position and angle of the second substrate W2 within the horizontal plane be determined, but also the relative position and angle between the second substrate W2 and the second fixed reference member 32r can be determined. If the alignment camera 45 captures the first reference mark 31m and the second reference mark 32m, the relative position and angle between the first fixed reference member 31r and the second fixed reference member 32r can be determined. This information indirectly allows the relative position and angle between the first substrate W1 and the second substrate W2 to be determined.

[0183] The control device 3 adjusts the relative position and angle between the first fixed reference member 31r and the second fixed reference member 32r so as to minimize the positional deviation between the first substrate W1 and the second substrate W2 while causing the alignment camera 45 to capture images of the first reference mark 31m and the second reference mark 32m.

[0184] Specifically, the control device 3 uses at least one of the first rotation motor 12, the second rotation motor 22, the Y actuator 25, and the X actuator 27 to move one or both of the first substrate W1 and the second substrate W2 within a horizontal plane. This minimizes the positional deviation between the first and second substrates W1 and W2. The control device 3 monitors changes in the positional deviation. When the positional deviation converges below a predetermined value, the alignment adjustment is completed and the alignment is determined to be complete. The alignment adjustment processing instructions are terminated, and the processing instructions for the next substrate contact step are restarted.

[0185] During the substrate contacting step, the control device 3 lowers the first substrate W1 using the Z actuator 18, bringing the downward-facing bonding surface WA1 of the first substrate W1 into contact with the upward-facing bonding surface WA2 of the second substrate W2. This bonds the first and second substrates W1 and W2. The parameters for the lowering operation, such as the movement distance, are based on a recipe stored in the memory 3c. The control device 3 completes the operations specified in the substrate contacting step and determines that bonding is complete.

[0186] After the first and second substrates W1 and W2 are bonded, the inspection camera 43 images the first and second substrates W1 and W2 while they are held by the second clamp 21. Thus, while the first and second substrates W1 and W2 are bonded, the inspection camera 43 images the first alignment mark AM1 and the second alignment mark AM2. The positional and angular deviations of the two bonded substrates W are measured based on the images of the first alignment mark AM1 and the second alignment mark AM2 generated by the inspection camera 43.

[0187] The first camera 41 is moved by the X actuator 27 and the Y actuator 25, thereby changing the position imaged by the first camera 41. The upper stage 23u is moved by the X actuator 27 and the Y actuator 25, thereby changing the position imaged by the second camera 42. The alignment camera 45 and the inspection camera 43 are similarly controlled as the second camera 42. The X actuator 27 and the Y actuator 25 also function as imaging position adjustment actuators that change the position imaged by the first camera 41 and other cameras. The bonding unit 2b may also include imaging position adjustment actuators that move the second camera 42 and the inspection camera 43 relative to the stage 20.

[0188] Figure 26 A schematic diagram showing an example of an image of the cross-shaped first alignment mark AM1 generated by the first camera 41 is shown.

[0189] The first camera 41 generates a rectangular or square two-dimensional image composed of a plurality of pixels arranged in orthogonal vertical and horizontal directions. The control device 3 receives electronic data of the still or moving image generated by the first camera 41. The control device 3 analyzes and determines the image based on a program stored in the memory 3c. The same applies to the second camera 42 and other cameras.

[0190] If first fiducial mark 31m has a shape that allows for a vertical and horizontal direction that are orthogonal to each other, then when first camera 41 captures an image of first fiducial mark 31m, the vertical and horizontal directions of first fiducial mark 31m are determined based on the image of first fiducial mark 31m. This allows for the determination of the tilt angle of first fiducial mark 31m relative to the image generated by first camera 41 (for example, the tilt angle of the width direction of first fiducial mark 31m relative to the horizontal direction of the image).

[0191] The height and width directions of first fiducial marker 31m are recorded in memory 3c in association with the shape of first fiducial marker 31m used. Control device 3 matches the shape of first fiducial marker 31m recorded in memory 3c with first fiducial marker 31m in the image generated by first camera 41, thereby determining the height and width directions of first fiducial marker 31m in the captured image.

[0192] If the first reference mark 31m has a shape that allows for definition of mutually orthogonal height and width directions, the first fixed reference member 31r may be arranged so that the longitudinal or lateral inclination angle of the first reference mark 31m relative to the image generated by the first camera 41 is below an upper limit. For example, if the outline of the first reference mark 31m includes a horizontal line parallel to the width direction, the first fixed reference member 31r may be arranged so that the horizontal inclination angle of the horizontal line relative to the image generated by the first camera 41 is below an upper limit. The same applies to the arrangement of the second fixed reference member 32r associated with the second reference mark 32m.

[0193] Similar to the first reference mark 31m, if the first alignment mark AM1 has a shape that allows for a defined height and width direction that are orthogonal to each other, then when the first camera 41 captures the first alignment mark AM1, the height and width directions of the first alignment mark AM1 are determined based on the image of the first alignment mark AM1. This allows for the determination of the tilt angle of the first alignment mark AM1 relative to the image generated by the first camera 41 (for example, the tilt angle of the width direction of the first alignment mark AM1 relative to the horizontal direction of the image).

[0194] When the first alignment mark AM1 has a shape such that its height and width directions are orthogonal to each other, the control device 3 may determine whether the longitudinal or lateral inclination angle of the first alignment mark AM1 relative to the image generated by the first camera 41 exceeds an upper limit. If it is determined that the inclination angle of the first alignment mark AM1 exceeds the upper limit, the control device 3 may cause the first rotation motor 12 to rotate the first jig 11 to reduce the inclination angle of the first alignment mark AM1 to below the upper limit, and then cause the first camera 41 to capture an image of the first alignment mark AM1.

[0195] Figure 26 An example of an image generated by the first camera 41 is shown on the left side of . Figure 26 The two gratings on the right are Figure 26 A part of the image on the left is enlarged. Each square block in each grating corresponds to a pixel. The boundary between the black block and the white block corresponds to the outline of the first alignment mark AM1. Figure 26In the upper right grating of , the outline of the first alignment mark AM1 is tilted relative to the horizontal direction of the image (left and right direction of the drawing). Figure 26 In the lower right grating, the outline of the first alignment mark AM1 is parallel to the horizontal direction of the image.

[0196] The control device 3 can, for example, cause the first rotation motor 12 to rotate the first clamp 11 so that the image generated by the first camera 41 is Figure 26 The state of the grating in the upper right corner changes to Figure 26 The state of the grating on the lower right side of the image is displayed. Thus, the shape of the first alignment mark AM1 can be determined with higher accuracy based on the image generated by the first camera 41, and the position and angle of the first substrate W1 can be determined with higher accuracy. The same applies when the second camera 42 captures the image of the second alignment mark AM2 and when the inspection camera 43 captures the image of the first alignment mark AM1 and the second alignment mark AM2.

[0197] Next, the displacement detector 46 will be described.

[0198] Figure 27 is a block diagram of the displacement detector 46. Figure 28 A diagram showing a vertical cross section of the displacement detector 46 . Figure 29 For Figure 28 The direction of arrow XXIX shown is a diagram showing the displacement detector 46 viewed vertically.

[0199] like Figure 27 As shown, the joining unit 2 b includes a displacement detector 46 for detecting relative displacement between the stage 20 and the second fixture 21 in the horizontal direction. Figure 28 as well as Figure 29 An example is shown in which the displacement detector 46 detects the displacement of the second jig 21 in the X direction and the Y direction relative to the stage 20 , thereby detecting the relative displacement of the stage 20 and the second jig 21 in the horizontal direction.

[0200] The displacement detector 46 includes an X displacement detector for detecting the relative displacement between the platform 20 and the second fixture 21 in the X direction, and a Y displacement detector for detecting the relative displacement between the platform 20 and the second fixture 21 in the Y direction. The Y displacement detector can be integrated with the X displacement detector or can be a separate displacement detector. Figure 27 An example of the former is shown.

[0201] The X-displacement detector can be an optical displacement detector or a magnetic displacement detector of another type. In the former case, the X-displacement detector can be a grating interferometry linear encoder or another type of displacement detector such as an interferometer. Compared to interferometers such as laser interferometers, grating interferometry linear encoders are less susceptible to environmental changes such as temperature and humidity, thus enabling stable displacement detection. The X-displacement detector can be an absolute position detector that detects the absolute position of an object such as the second substrate W2, or a relative position detector that detects the relative position of an object. The content of this paragraph also applies to the Y-displacement detector. If the Y-displacement detector is independent of the X-displacement detector, the Y-displacement detector can be a different type of displacement detector from the X-displacement detector.

[0202] Figure 27 The example shown includes a grating interferometry linear encoder that detects displacement of the second substrate W2 in the X and Y directions. The grating interferometry displacement detector 46 includes a scale 47 that moves in the X and Y directions along with an object, such as the second jig 21, and a detection head 48 that detects displacement of the scale 47 in the X and Y directions. The detection head 48 is a non-contact displacement meter that detects displacement of the scale 47 in the X and Y directions without contacting the scale 47.

[0203] The detection head 48 includes an X detection head 48x, which detects the Y-direction displacement of the scale 47, and a Y detection head 48y, which detects the Y-direction displacement of the scale 47. Both the X detection head 48x and the Y detection head 48y include a light source 48s, which emits light reflected by the scale 47; a light receiving element 48r, which converts the light reflected by the scale 47 into an electrical signal; and an interpolator 48i, which calculates the horizontal movement amount and direction of the scale 47 based on the electrical signal input from the light receiving element 48r. The displacement of the second substrate W2 detected by the displacement detector 46 is input to the control device 3 via the interpolator 48i.

[0204] Scale 47 is a reflective diffraction grating that reflects light emitted by a light source 48s, such as a semiconductor laser. Scale 47 can be a holographic diffraction grating or another type of diffraction grating, such as a blazed diffraction grating. Scale 47 can be a planar diffraction grating or a volume diffraction grating. Figure 29 The scale 47 is shown as a 2D scale (two-dimensional scale) that reflects light emitted by the X detection head 48x and the Y detection head 48y. In this example, the scale 47 includes a square reflecting surface 47s that reflects light emitted by the light source 48s.

[0205] The 2D scale includes: an X-ray diffraction grating having a concave-convex surface with convex portions protruding in the Z direction and concave portions recessed in the Z direction arranged regularly and alternately in the X direction; and a Y-ray diffraction grating having a concave-convex surface with convex portions protruding in the Z direction and concave portions recessed in the Z direction arranged regularly and alternately in the Y direction. The Y-ray diffraction grating moves horizontally in the same direction, at the same speed, and with the same amount of movement as the X-ray diffraction grating. The front ends of the convex portions of the X-ray diffraction grating and the front ends of the convex portions of the Y-ray diffraction grating are arranged on a horizontal plane. The concave-convex surface of the X-ray diffraction grating and the concave-convex surface of the Y-ray diffraction grating are part of the reflective surface 47s of the scale 47. Light emitted by the light source 48s is reflected by the concave-convex surface of the X-ray diffraction grating or the concave-convex surface of the Y-ray diffraction grating.

[0206] The concave portion of the X-ray diffraction grating can be a continuous groove longer than its width extending in the Y direction, or a plurality of holes arranged in the Y direction, or a combination of both. The concave portion of the Y-ray diffraction grating can be a continuous groove longer than its width extending in the X direction, or a plurality of holes arranged in the X direction, or a combination of both. The vertical cross-section of the convex and concave portions of the X-ray diffraction grating can be any of a circular arc, a square, a rectangle, or other shapes. The same applies to the vertical cross-section of the convex and concave portions of the Y-ray diffraction grating.

[0207] The scale 47 is fixed to the lower surface of the upper workbench 23u with the reflecting surface 47s for reflecting light facing downward. If the upper workbench 23u moves in the Y direction relative to the stage 20, the scale 47 moves horizontally in the same direction, at the same speed, and by the same amount as the upper workbench 23u. If the lower workbench 23L moves in the X direction relative to the stage 20, the scale 47 moves horizontally in the same direction, at the same speed, and by the same amount as the lower workbench 23L. If the second substrate W2 held by the second clamp 21 moves horizontally in at least one of the X and Y directions relative to the stage 20, the scale 47 moves horizontally in the same direction, at the same speed, and by the same amount as the second substrate W2. Even if the upper workbench 23u moves in the Y direction relative to the lower workbench 23L, the scale 47 will not collide with the lower workbench 23L.

[0208] The detection head 48 is arranged below the scale 47 and the upper workbench 23u. The detection head 48 is directly opposite to the scale 47 in the Z direction. The detection head 48 is inserted into the through window 23w that passes through the lower workbench 23L from top to bottom. The detection head 48 is fixed to the base 20. The detection head 48 includes: a light-emitting portion 48e that is directly opposite to the scale 47 in the Z direction; and a main body 48m that supports the light-emitting portion 48e. The main body 48m is inserted into the through window 23w of the lower workbench 23L. The light-emitting portion 48e is arranged above the upper surface of the lower workbench 23L. Even when the second fixture 21 is in a deviated position, the detection head 48 will not contact the lower workbench 23L.

[0209] Even when the second jig 21 is located at a deviated position, the light emitting portion 48e is directly facing the scale 47 in the Z direction. Figure 27 ) travels from the light emitting unit 48e to the scale 47, where it is reflected. The light then travels from the light emitting unit 48e into the detection head 48. The detection head 48 detects the displacement of the scale 47 relative to the stage 20 in the X and Y directions. This detects the displacement of the second fixture 21 relative to the stage 20 in the X and Y directions. The detection results for the displacement in the X and Y directions are transmitted to the control device 3.

[0210] Next, the electrical configuration of the substrate bonding apparatus 1 will be described.

[0211] Figure 30 This is a block diagram showing the electrical configuration of substrate bonding apparatus 1. The control device 3 sends control signals to control the electrical and electronic devices included in substrate bonding apparatus 1. Furthermore, the control device 3 receives signals from various cameras and detectors included in substrate bonding apparatus 1, and stores and processes these signals. The control device 3 is programmed to execute the various processes described below.

[0212] The control device 3 includes at least one computer. The computer comprises a main computer 3a and peripheral devices 3d connected to the main computer 3a. The main computer 3a includes a CPU (Central Processing Unit) 3b, which executes various commands, and a memory 3c, which stores information. The peripheral devices 3d include a storage 3e, which stores information such as programs P and is sent and received between the storage 3e and the memory 3c; a reader 3f, which reads information from a removable medium RM; and a communication device 3g, which communicates with other devices such as a host computer.

[0213] The control device 3 is connected to an input device and a display device. The input device is operated by an operator, such as a user or maintenance personnel, to input information into the substrate bonding apparatus 1. This information is displayed on the display screen of the display device. The input device can be any of a keyboard, a pointing device, and a touch panel, or other devices. The substrate bonding apparatus 1 can also be provided with a touch panel display that serves as both an input device and a display device.

[0214] The CPU 3b executes the program P stored in the memory 3e. The program P in the memory 3e may be pre-installed in the control device 3, transferred to the memory 3e from the removable medium RM via the reader 3f, or transferred to the memory 3e from an external device such as a host computer via the communication device 3g.

[0215] Memory 3c is volatile memory that retains data only while power is supplied. Storage 3e and removable media RM are non-volatile memory that retains data even when power is not supplied. Storage 3e is, for example, a magnetic storage device such as a hard disk drive. Removable media RM is, for example, an optical disk such as a compact disc or a semiconductor memory such as a memory card. Removable media RM is an example of a computer-readable recording medium that stores program P. Removable media RM is non-transitory tangible media.

[0216] Next, a first example of bonding the first substrate W1 and the second substrate W2 will be described.

[0217] Figure 31A 、 Figure 31B 、 Figure 31C 、 Figure 31D 、 Figure 31E 、 Figure 31F 、 Figure 31G as well as Figure 31H It is a schematic diagram for explaining a first example of joining the first substrate W1 and the second substrate W2 by the joining unit 2b. Figures 31A to 31H The first jig 11 and the second jig 21 and the like are shown as viewed horizontally in the Y direction. Figure 32A as well as Figure 32B Same here.

[0218] When the first substrate W1 and the second substrate W2 are bonded together by the bonding unit 2b, as shown in FIG. Figure 31AAs shown, the transport robot TR positions the first substrate W1 in the space above the first fixture 11 in the loading / unloading state while holding the first substrate W1 horizontally with its bonding surface WA1 facing upward using the robot hand TH. Similarly, the transport robot TR positions the second substrate W2 in the space above the second fixture 21 in the loading / unloading state while holding the second substrate W2 horizontally with its bonding surface WA2 facing upward using the robot hand TH.

[0219] The first gripper 11 is in the following state during loading and unloading: the first gripper 11 maintains a position and posture that enables the first substrate W1 to be moved between the transport robot TR and the first gripper 11, the rotation angle of the first gripper 11 is zero, and the centerline 11c of the first gripper 11 is vertical. The second gripper 21 is in the following state during loading and unloading: the second gripper 21 maintains a position and posture that enables the second substrate W2 to be moved between the transport robot TR and the second gripper 21, and the rotation angle of the second gripper 21 is zero.

[0220] The transport robot TR can place the first substrate W1 on the first clamp 11 in the carry-in / carry-out state, or it can place the first substrate W1 on a plurality of lift pins that support the first substrate W1 horizontally between a lower position and an upper position while moving up and down. The lower position is where the first substrate W1 is placed on the first clamp 11, and the upper position is where the first substrate W1 is separated upward from the first clamp 11. The same applies to the second substrate W2. In any case, the first substrate W1 is placed on the first clamp 11 in the carry-in / carry-out state with its bonding surface WA1 facing upward and is adsorbed by the first clamp 11. Similarly, the second substrate W2 is placed on the second clamp 21 in the carry-in / carry-out state with its bonding surface WA2 facing upward and is adsorbed by the second clamp 21.

[0221] When the first suction surface 11s of the first clamp 11 is horizontal during loading / unloading, the upper surface (joining surface WA1) and lower surface of the first substrate W1 remain horizontal even after the first substrate W1 is adsorbed by the first clamp 11. If the first suction surface 11s of the first clamp 11 is not horizontal during loading / unloading, when the first substrate W1 is adsorbed by the first clamp 11, the upper and lower surfaces of the first substrate W1 elastically deform from a horizontal plane to a shape identical or substantially identical to that of the first suction surface 11s of the first clamp 11, and maintain that shape. The same applies to the shapes of the upper and lower surfaces of the second substrate W2.

[0222] Figure 31AThe following example illustrates a horizontal surface, with the first suction surface 11s of the first gripper 11 and the second suction surface 21s of the second gripper 21 both being horizontal. Therefore, in this example, after the first substrate W1 is attracted to the first gripper 11, its upper and lower surfaces remain horizontal. Similarly, after the second substrate W2 is attracted to the second gripper 21, its upper and lower surfaces also remain horizontal.

[0223] The first substrate W1 can be placed on the first jig 11 before or after the second substrate W2 is placed on the second jig 21, or it can be placed on the first jig 11 while the second substrate W2 is placed on the second jig 21. The robot TH that transports the first substrate W1 can be the same as or different from the robot TH that transports the second substrate W2. In the latter case, the first and second substrates W1 and W2 can be transported by two robots TH of a single transport robot TR, or by two transport robots TR.

[0224] If the first substrate W1 is placed on the first fixture 11, Figure 31B As shown, the flip actuator 16 rotates the first clamp 11 180 degrees, orienting the bonding surface WA1 of the first substrate W1 downward. Before or after this, the upper stage 23u is positioned within an imaging area where the first narrow-field-of-view camera 41n and the first wide-field-of-view camera 41w mounted on the upper stage 23u can capture images of at least one of the first substrate W1 and the first fixed reference member 31r. In this state, the first narrow-field-of-view camera 41n and the first wide-field-of-view camera 41w begin capturing images. As needed, the first narrow-field-of-view camera 41n and the first wide-field-of-view camera 41w can be moved horizontally relative to the first substrate W1 during the imaging process.

[0225] The first narrow field of view camera 41n and the first wide field of view camera 41w capture images of at least one first alignment mark AM1 on the first substrate W1 and at least one first reference mark 31m on the first fixed reference member 31r. The first narrow field of view camera 41n and the first wide field of view camera 41w then terminate their capture. By analyzing the captured images of the at least one first alignment mark AM1, the position and angle of the first substrate W1 are determined. Similarly, by analyzing the captured images of the at least one first reference mark 31m, the position and angle of the first fixed reference member 31r are determined. This allows the position and angle of the first substrate W1 relative to the first fixed reference member 31r to be determined.

[0226] For example, the coordinate position of the first narrow field of view camera 41n when the first alignment mark AM1 is captured can be calculated based on the device design information and the output of the displacement detector 46 (described later). The coordinate position of the first alignment mark AM1 can be determined based on the calculated coordinate position of the first narrow field of view camera 41n and the position of the first alignment mark AM1 in the captured image. The coordinate position of the first reference mark 31m can also be determined using the same method. The relative position of the first alignment mark AM1 and the first reference mark 31m can then be calculated, thereby determining the position of the first substrate W1 relative to the first fixed reference member 31r.

[0227] If the second substrate W2 is placed on the second fixture 21, Figure 31C As shown, the upper stage 23u is positioned within an imaging area where the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w can capture images of at least one of the second substrate W2 and the second fixed reference member 32r. In this state, the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w begin capturing images. As needed, the upper stage 23u can be moved horizontally relative to the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w during the capture process.

[0228] The second narrow field of view camera 42n and the second wide field of view camera 42w capture images of at least one second alignment mark AM2 on the second substrate W2 and at least one second reference mark 32m on the second fixed reference member 32r. The second narrow field of view camera 42n and the second wide field of view camera 42w then terminate their capture. The captured images of the at least one second alignment mark AM2 are analyzed to determine the position and angle of the second substrate W2. Similarly, the captured images of the at least one second reference mark 32m are analyzed to determine the position and angle of the second fixed reference member 32r. This allows the position and angle of the second substrate W2 relative to the second fixed reference member 32r to be determined.

[0229] For example, the position of the second jig 21 when the second alignment mark AM2 is captured can be determined based on the output of the displacement detector 46 (described later). Based on the position of the second alignment mark AM2 in the captured image, the coordinate position of the second alignment mark AM2, which is associated with the position of the second jig 21, can be determined. The second reference mark 32m can also be determined in a similar manner, associated with the position of the second jig 21. The coordinate position of the second alignment mark AM2 when the second reference mark 32m is captured can be calculated based on the position of the second jig 21 when the second reference mark 32m is captured and the position of the second jig 21 when the second alignment mark AM2 is captured. This allows the relative position of the second alignment mark AM2 and the second reference mark 32m to be calculated. This also allows the position of the second substrate W2 relative to the second fixed reference member 32r to be determined.

[0230] At least a portion of the time during which the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w capture images of the second substrate W2 and the second fixed reference member 32r may coincide with or differ from the time during which the first narrow-field-of-view camera 41n and the first wide-field-of-view camera 41w capture images of the first substrate W1 and the first fixed reference member 31r. At least a portion of the time during which the second alignment mark AM2 of the second substrate W2 held by the second fixture 21 is captured may coincide with or differ from the time during which the second reference mark 32m is captured. The same applies to the time during which the first alignment mark AM1 and the first reference mark 31m are captured.

[0231] After determining the position and angle of the first substrate W1 relative to the first fixed reference member 31r and the position and angle of the second substrate W2 relative to the second fixed reference member 32r, the control device 3 operates the actuator mechanism AC, thereby changing the first and second substrates W1, W2 from a non-opposing state to an opposing state. The control device 3 then operates the actuator mechanism AC, thereby changing the first and second substrates W1, W2 from an opposing state to an aligned state. The control device 3 then operates the actuator mechanism AC, thereby changing the first and second substrates W1, W2 from an aligned state to a bonded state.

[0232] The non-opposing state is a state in which the first substrate W1 and the second substrate W2 do not overlap when the first substrate W1 and the second substrate W2 are observed vertically. The opposing state and the alignment completed state are states in which the entire area of ​​the bonding surface WA1 of the first substrate W1 and the entire area of ​​the bonding surface WA2 of the second substrate W2 are separated from each other, and the first substrate W1 and the second substrate W2 are facing each other from top to bottom. The opposing state is a state before the alignment of the first substrate W1 and the second substrate W2 is performed, and the alignment completed state is a state after the alignment of the first substrate W1 and the second substrate W2 is performed. The opposing state is a non-aligned state. The bonding completed state is a state in which the entire area of ​​the bonding surface WA1 of the first substrate W1 and the entire area of ​​the bonding surface WA2 of the second substrate W2 are in contact.

[0233] When the first substrate W1 and the second substrate W2 are changed from the non-opposing state to the opposing state, the upper table 23u and the lower table 23L are moved in the X direction with the bonding surface WA1 of the first substrate W1 held by the first clamp 11 facing downward, thereby moving the second substrate W2 held by the second clamp 21 in the X direction relative to the first substrate W1 held by the first clamp 11. Figure 31D As shown, the first substrate W1 and the second substrate W2 are facing each other in the vertical direction in a state where the entire area of ​​the bonding surface WA1 of the first substrate W1 and the entire area of ​​the bonding surface WA2 of the second substrate W2 are separated from each other.

[0234] After the first substrate W1 and the second substrate W2 are changed to the opposing state, in the state where the bonding surface WA1 of the first substrate W1 held by the first clamp 11 is facing downward, the first substrate W1 and the second substrate W2 are moved relative to each other in at least one direction of the X direction, the Y direction, the first θ direction (the circumferential direction of the first substrate W1) and the second θ direction (the circumferential direction of the second substrate W2). As a result, the first substrate W1 and the second substrate W2 are changed from the opposing state to the alignment completed state. Thereafter, the first workbench 13 is moved in the Z direction, thereby lowering the first substrate W1 held by the first clamp 11 relative to the second substrate W2 held by the second clamp 21. As a result, as Figure 31E As shown, the entire bonding surface WA1 of the first substrate W1 contacts the entire bonding surface WA2 of the second substrate W2 , and the first substrate W1 and the second substrate W2 change from the alignment completed state to the bonding completed state.

[0235] The bonding completed state is a state in which the first substrate W1 and the second substrate W2 are aligned using at least one first alignment mark AM1 and at least one second alignment mark AM2 as a reference. The difference between the alignment completed state and the bonding completed state may be solely whether the first substrate W1 and the second substrate W2 are separated from each other. In other words, the alignment completed state may be a state in which the first substrate W1 and the second substrate W2 are separated from each other, and the positional deviation between the first substrate W1 and the second substrate W2 is minimized.

[0236] like Figure 31D As shown, the facing state of the first substrate W1 and the second substrate W2 is when the first fixed reference member 31r and the second fixed reference member 32r are viewed vertically, and the first fixed reference member 31r and the second fixed reference member 32r are overlapped. Before or after the first substrate W1 and the second substrate W2 are facing each other, the alignment camera 45 mounted on the first stage 13 begins imaging. As a result, the alignment camera 45 captures the first fixed reference member 31r and the second fixed reference member 32r in a top-down overlapping state.

[0237] The control device 3 analyzes the image of the first fixed reference member 31r captured by the alignment camera 45 to determine the position and angle of the first fixed reference member 31r. Similarly, the control device 3 analyzes the image of the second fixed reference member 32r captured by the alignment camera 45 to determine the position and angle of the second fixed reference member 32r. Because the first narrow-field-of-view camera 41n and the first wide-field-of-view camera 41w have already captured images of the first substrate W1 and the first fixed reference member 31r, the position and angle of the first substrate W1 can be indirectly determined based on the position and angle of the first fixed reference member 31r. Similarly, because the second narrow-field-of-view camera 42n and the second wide-field-of-view camera 42w have already captured images of the second substrate W2 and the second fixed reference member 32r, the position and angle of the second substrate W2 can be indirectly determined based on the position and angle of the second fixed reference member 32r. Therefore, by adjusting the relative position and angle of the first and second fixed reference members 31r and 32r, the first and second substrates W1 and W2 can be indirectly aligned.

[0238] The control device 3 causes the alignment camera 45 to image the first fixed reference member 31r and the second fixed reference member 32r while moving the first substrate W1 and the second substrate W2 relative to each other in at least one of the X direction, the Y direction, the first θ direction, and the second θ direction. This aligns the first and second substrates W1, W2, while they are spaced apart from each other, and the alignment is complete. After the control device 3 determines that the alignment of the first and second substrates W1, W2 has been completed, the alignment camera 45 stops imaging.

[0239] After the first substrate W1 and the second substrate W2 have reached the aligned state, the control device 3 moves the first substrate W1 and the second substrate W2 relative to each other at least in the Z direction, thereby bringing the entire area of ​​the bonding surface WA1 of the first substrate W1 into contact with the entire area of ​​the bonding surface WA2 of the second substrate W2. Thus, the first substrate W1 and the second substrate W2 move from the aligned state to the bonded state. After the first substrate W1 and the second substrate W2 have reached the bonded state, the first clamp 11 releases its grip on the first substrate W1, while the second clamp 21 continues to hold the second substrate W2. Thus, the bonded first and second substrates W1 and W2 are held by the second clamp 21.

[0240] After the first substrate W1 and the second substrate W2 are changed to the bonding completed state, as shown in FIG. Figure 31F As shown, the control device 3 raises the first clamp 11 and moves the second clamp 21 back (towards the negative side of the X direction). Figure 31GAs shown, the flip actuator 16 rotates the first clamp 11 in such a way that the center line 11c of the first clamp 11 becomes vertical, thereby making the first clamp 11 face upward. As needed, the first rotation motor 12 rotates the first clamp 11 so that the rotation angle of the first clamp 11 returns to zero. As a result, the first clamp 11 returns to the carry-in and carry-out state. The flip actuator 16 can start rotating the first clamp 11 before or after the second clamp 21 retreats, or it can start rotating the first clamp 11 while the second clamp 21 retreats. The same applies to the first rotation motor 12.

[0241] After the first substrate W1 and the second substrate W2 are changed to the bonding completed state, as shown in FIG. Figure 31G As shown, the upper stage 23u is positioned in an imaging area where the inspection camera 43 can capture images of the first substrate W1 and the second substrate W2 on the second fixture 21. Before or after this, the inspection camera 43 begins capturing images. This allows the at least one first alignment mark AM1 and at least one second alignment mark AM2 to be captured while the first and second substrates W1 and W2 are bonded. If necessary, the upper stage 23u can be moved horizontally relative to the inspection camera 43 during the capturing process.

[0242] The images of the first alignment mark AM1 and the second alignment mark AM2 taken by the inspection camera 43 are sent to the control device 3 and analyzed. Through the analysis, the bonding accuracy of the first substrate W1 and the second substrate W2 is detected. Furthermore, based on the detected bonding accuracy of the first substrate W1 and the second substrate W2, the alignment change of the first substrate W1 and the second substrate W2 between the alignment completion state and the bonding completion state is detected. When bonding other first substrates W1 and second substrates W2, the alignment of the first substrate W1 and the second substrate W2 in the alignment completion state is corrected based on the detected alignment change. Thus, the subsequent first substrates W1 and second substrates W2 are bonded with higher accuracy.

[0243] After the inspection camera 43 captures the first substrate W1 and the second substrate W2 on the second clamp 21, the second clamp 21 is moved in the X direction until the second clamp 21 returns to the state of being carried in and out while the first substrate W1 and the second substrate W2 are held in contact by the second clamp 21. As needed, the second rotation motor 22 rotates the second clamp 21 to return the rotation angle of the second clamp 21 to zero. Figure 31H As shown, the second clamp 21 releases the second substrate W2, and the robot hand TH of the transport robot TR directly or indirectly receives the first substrate W1 and the second substrate W2 from the second clamp 21. Thus, the bonded first substrate W1 and second substrate W2 are held horizontally by the robot hand TH of the transport robot TR and transported to the next destination.

[0244] When the next first substrate W1 and the second substrate W2 are joined, the above series of steps are repeated. The next first substrate W1 can be placed on the first jig 11 before or after the previous first substrate W1 and the second substrate W2 are unloaded from the second jig 21, or can be placed on the first jig 11 at the same time as the previous first substrate W1 and the second substrate W2 are unloaded from the second jig 21. For example, Figure 31G As shown, while the inspection camera 43 is photographing the bonded first substrate W1 and the second substrate W2, the next first substrate W1 can be placed on the first fixture 11. In this case, as shown in FIG. Figure 31H As shown, before the previous first substrate W1 and the second substrate W2 are unloaded from the second clamp 21 , the reversing actuator 16 may reverse the next first substrate W1 .

[0245] Next, a second example of bonding the first substrate W1 and the second substrate W2 will be described.

[0246] Figure 32A as well as Figure 32B It is a schematic diagram for explaining a second example of joining the first substrate W1 and the second substrate W2 by the joining unit 2 b.

[0247] As described above, the first substrate W1 and the second substrate W2 change from a non-opposing state to an opposing state and an alignment completed state to a bonding completed state. The bonding completed state is a state in which the entire area of ​​the bonding surface WA1 of the first substrate W1 contacts the entire area of ​​the bonding surface WA2 of the second substrate W2. The alignment completed state can be a state in which the entire area of ​​the bonding surface WA1 of the first substrate W1 and the entire area of ​​the bonding surface WA2 of the second substrate W2 are parallel or non-parallel, or a state in which a portion of the bonding surface WA1 of the first substrate W1 is parallel to a portion of the bonding surface WA2 of the second substrate W2, and the remaining portion of the bonding surface WA1 of the first substrate W1 is non-parallel to the remaining portion of the bonding surface WA2 of the second substrate W2.

[0248] That is, in addition to whether the first substrate W1 and the second substrate W2 are separated from each other (the position of the first substrate W1 relative to the second substrate W2 in the vertical direction), the alignment completion state may also be different from the bonding completion state in at least one of the following: the position of the first substrate W1 relative to the second substrate W2 in the horizontal direction; the posture of the first substrate W1 relative to the second substrate W2; the relative angle between the first substrate W1 and the second substrate W2 around the vertical line; the shape of the bonding surface WA1 of the first substrate W1; and the shape of the bonding surface WA2 of the second substrate W2.

[0249] Figures 31A to 31HThe following example illustrates bonding the first substrate W1 and the second substrate W2 by simultaneous full bonding, where the entire bonding surface WA1 of the first substrate W1 and the entire bonding surface WA2 of the second substrate W2 are brought into contact simultaneously or substantially simultaneously. However, the first substrate W1 and the second substrate W2 may also be bonded by shifting boundary bonding, where the bonding area of ​​the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are expanded.

[0250] The boundary movement bonding is: the boundary between the contact area within the bonding surface WA1 of the first substrate W1 that contacts the bonding surface WA2 of the second substrate W2 and the non-contact area within the bonding surface WA1 of the first substrate W1 that is separated from the bonding surface WA2 of the second substrate W2 is moved within the bonding surface WA1 of the first substrate W1 until the entire area of ​​the bonding surface WA1 of the first substrate W1 contacts the entire area of ​​the bonding surface WA2 of the second substrate W2.

[0251] During boundary shift bonding, the first substrate W1 and the second substrate W2 are moved from the alignment completed state to the bonding completed state via the bonding start state and the bonding extended state. Although strictly speaking, there are also periods of the bonding start state and the bonding extended state when the first substrate W1 and the second substrate W2 are bonded by full simultaneous bonding, these periods are extremely short and therefore are considered to have moved from the alignment completed state to the bonding completed state without passing through the bonding start state and the bonding extended state.

[0252] Both the joining start state and the joining expansion state are states in which the first substrate W1 and the second substrate W2 are halfway through changing from the alignment completion state to the joining completion state. The joining start state is a state in which the joining surface WA1 of the first substrate W1 and the joining surface WA2 of the second substrate W2 begin to contact each other. The joining expansion state is a state in which the area in which the joining surface WA1 of the first substrate W1 and the joining surface WA2 of the second substrate W2 are in contact is widened until the entire area of ​​the joining surface WA1 of the first substrate W1 and the entire area of ​​the joining surface WA2 of the second substrate W2 are in contact. Both the joining start state and the joining expansion state are states in which a portion of the joining surface WA1 of the first substrate W1 is in contact with a portion of the joining surface WA2 of the second substrate W2 and the remaining portion of the joining surface WA1 of the first substrate W1 is separated from the remaining portion of the joining surface WA2 of the second substrate W2.

[0253] In the alignment completion state, the bonding start state, the bonding expansion state and the bonding completion state, at least one of the following is different from each other: the position of the first substrate W1 relative to the second substrate W2 in the vertical direction; the position of the first substrate W1 relative to the second substrate W2 in the horizontal direction; the posture of the first substrate W1 relative to the second substrate W2; the relative angle between the first substrate W1 and the second substrate W2 around the vertical straight line; the shape of the bonding surface WA1 of the first substrate W1; the shape of the bonding surface WA2 of the second substrate W2.

[0254] In addition to at least one of the differences described above, the areas of contact between the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 also differ from one another in the bonding start state, the bonding expansion state, and the bonding completion state. The bonding expansion state represents all the continuous states of the first substrate W1 and the second substrate W2 from the bonding start state to the bonding completion state. During the process of the first substrate W1 and the second substrate W2 changing from the bonding start state to the bonding expansion state to the bonding completion state, the entire area of ​​the bonding surface WA1 of the first substrate W1 is bonded to the entire area of ​​the bonding surface WA2 of the second substrate W2 while the first substrate W1 and the second substrate W2 are aligned.

[0255] For example, Figure 32A As shown, the alignment completion state may be the following state: the entire area of ​​the bonding surface WA1 of the first substrate W1 is arranged in a plane inclined relative to the horizontal plane, and the entire area of ​​the bonding surface WA2 of the second substrate W2 is arranged in a horizontal plane. Specifically, the flip actuator 16 may adjust the angle of the first workbench 13 so that the downward bonding surface WA1 of the first substrate W1 is inclined relative to the horizontal plane. In this case, after the alignment adjustment of the first substrate W1 and the second substrate W2 is performed in a state where the bonding surface WA1 of the first substrate W1 is horizontal, the bonding surface WA1 of the first substrate W1 is tilted, and the relative positions of the first substrate W1 and the second substrate W2 in the horizontal direction are adjusted according to the tilt angle of the bonding surface WA1 of the first substrate W1 relative to the horizontal plane.

[0256] When the downwardly directed bonding surface WA1 of the first substrate W1 is tilted relative to the horizontal plane, a portion of the outer periphery of the bonding surface WA1 of the first substrate W1 corresponds to the lower end of the first substrate W1 that is arranged lower than the other portions of the bonding surface WA1 of the first substrate W1. The lower end of the first substrate W1 corresponds to the bonding start position that initially contacts the bonding surface WA2 of the second substrate W2. When the first substrate W1 and the second substrate W2 are changed from the alignment completion state to the bonding start state, as shown in FIG. Figure 32BAs shown, the lower end of the first substrate W1 is brought into contact with the bonding surface WA2 of the second substrate W2. Thereafter, the first substrate W1 is rotated relative to the second substrate W2 about a horizontal straight line that is parallel to the flip center 16c of the first clamp 11 and passes through the lower end of the first substrate W1, thereby rotating the first substrate W1 about the flip center 16c and moving the first and second substrates W2 relative to each other in the Z and X directions.

[0257] The area of ​​the region where the bonding surface WA1 of the first substrate W1 contacts the bonding surface WA2 of the second substrate W2 increases continuously as the inclination angle of the bonding surface WA1 of the first substrate W1 relative to the horizontal plane decreases. If the bonding surface WA1 of the first substrate W1 becomes horizontal, the entire area of ​​the bonding surface WA1 of the first substrate W1 contacts the entire area of ​​the bonding surface WA2 of the second substrate W2. As a result, the first substrate W1 and the second substrate W2 change from a bonding start state to a bonding expansion state to a bonding completion state. In this way, as long as the first substrate W1 and the second substrate W2 are bonded, bubbles (also called voids) remaining between the bonded first substrate W1 and second substrate W2 can be eliminated or reduced.

[0258] After the first substrate W1 and the second substrate W2 are brought into the bonded state, the first clamp 11 releases its grip on the first substrate W1. The first clamp 11 is not limited to having multiple suction regions that independently generate suction. The control device 3 can release the grip on the first substrate W1 at the contact region where the bonding surface WA1 of the first substrate W1 contacts the bonding surface WA2 of the second substrate W2, reducing the number of suction regions generating suction as the area of ​​the contact region increases.

[0259] Specifically, in multiple adsorption regions such as Figure 10B In the case of the configuration and shape shown, the control device 3 can be Figure 10B The adsorption area on the right side of Figure 10B The suction force is stopped in each suction area until the left end of the suction area. Figure 10B A vertically extending boundary is formed between the suction area where suction is generated and the suction area where suction is not generated, and this boundary moves from the right end of the first suction surface 11s to the left end of the first suction surface 11s. This allows the area of ​​contact between the first clamp 11 and the first substrate W1 to decrease while the area of ​​contact between the first substrate W1 and the second substrate W2 to increase simultaneously.

[0260] The alignment is completed when the bonding surface WA1 of the first substrate W1 elastically deforms into a downwardly convex spherical crown or other shape, and the entire bonding surface WA2 of the second substrate W2 lies within a single horizontal plane. In this case, the alignment is completed when the entire bonding surface WA1 of the first substrate W1 returns to a flat surface, minimizing the positional deviation between the first and second substrates W1 and W2.

[0261] Specifically, when the bonding surface WA1 of the first substrate W1 is elastically deformed and the shape of the bonding surface WA1 of the first substrate W1 in the aligned state can be estimated, the position of the first substrate W1 in the aligned state can be corrected based on the estimated shape. Regardless of whether the shape of the bonding surface WA1 of the first substrate W1 in the aligned state can be estimated, the shape of the bonding surface WA1 of the first substrate W1 in the aligned state can be measured, and the position of the first substrate W1 in the aligned state can be corrected based on the measured shape. For example, a distance meter such as a laser rangefinder can be used to measure the vertical distance from a horizontal plane to multiple positions within the bonding surface WA1 of the first substrate W1, and the position of the first substrate W1 in the aligned state can be corrected based on the value obtained through the measurement.

[0262] When the first substrate W1 and the second substrate W2 are changed from the alignment completed state to the bonding start state, the lowest portion of the bonding surface WA1 of the first substrate W1 is brought into contact with the bonding surface WA2 of the second substrate W2. Thereafter, while changing at least one of the horizontal position of the first substrate W1 relative to the second substrate W2, the posture of the first substrate W1 relative to the second substrate W2, the relative angle between the first substrate W1 and the second substrate W2 around the vertical line, the shape of the bonding surface WA1 of the first substrate W1, and the shape of the bonding surface WA2 of the second substrate W2, the spacing between the first substrate W1 and the second substrate W2 is reduced. As a result, the entire area of ​​the bonding surface WA1 of the first substrate W1 contacts the entire area of ​​the bonding surface WA2 of the second substrate W2, and the first substrate W1 and the second substrate W2 change from the bonding start state to the bonding completed state via the bonding expanded state.

[0263] Next, the effects of this embodiment will be described.

[0264] In this embodiment, the bonding unit 2b of the substrate bonding apparatus 1 not only bonds the first substrate W1 and the second substrate W2 but also inspects the bonding accuracy of the bonded first and second substrates W1 and W2. Therefore, the first and second substrates W1 and W2 can be held in the bonding unit 2b until their bonding accuracy is inspected. This shortens the time it takes to transport the first and second substrates W1 and W2.

[0265] In this embodiment, the second substrate W2 is held by the second clamp 21 before being bonded to the first substrate W1, and is also held by the second clamp 21 when the inspection camera 43 is capturing images of the bonded first and second substrates W1 and W2. Therefore, the second substrate W2 does not need to be removed from the second clamp 21 until the bonding accuracy of the first and second substrates W1 and W2 has been inspected. This shortens the time required to transport the first and second substrates W1 and W2.

[0266] In this embodiment, the bonding unit 2b is disposed within the outer wall 1a of the substrate bonding apparatus 1, and the first clamp 11, the second clamp 21, and the inspection camera 43 are disposed within the chamber 9 of the bonding unit 2b. Therefore, the first and second substrates W1, W2 do not need to be moved outside the chamber 9 before the bonding accuracy of the first and second substrates W1, W2 is inspected. This shortens the time required to transport the first and second substrates W1, W2.

[0267] In this embodiment, the first jig 11, the second jig 21, and the inspection camera 43 are arranged above the stage 20 of the bonding unit 2b and overlap with the stage 20 when viewed from above. In other words, the first jig 11, the second jig 21, and the inspection camera 43 are arranged directly above the stage 20. This allows the first and second substrates W1, W2 to be prevented from moving from the space directly above the stage 20 until their bonding accuracy is inspected. This shortens the time it takes to transport the first and second substrates W1, W2.

[0268] In this embodiment, a laser interferometer is not used. Instead, a grating interferometer-type displacement detector 46 is used to detect the relative displacement between the stage 20 and the second fixture 21. Compared to interferometers such as laser interferometers, the grating interferometer-type displacement detector 46 is less susceptible to environmental changes such as temperature and humidity changes, and thus can stably detect displacement. Furthermore, the displacement detector 46 can detect not only the relative displacement of the stage 20 and the second fixture 21 in the Y direction, but also the relative displacement of the stage 20 and the second fixture 21 in the X direction. Therefore, compared to the case where a detector for the Y direction and a detector for the X direction are provided, the relative displacement of the stage 20 and the second fixture 21 can be detected with higher accuracy.

[0269] In this embodiment, the displacement detector 46 detects the displacement of the second jig 21 in the X and Y directions. Furthermore, the first jig 11 is supported by the first frame 19 fixed to the base 20. By stopping the operation of the inversion actuator 16, the first jig 11 can be held while its position in the X and Y directions is fixed. Therefore, even without detecting the displacement of the first jig 11 in the X and Y directions, the relative positions of the first jig 11 and the second jig 21 in the X and Y directions can be adjusted.

[0270] In this embodiment, the detection head 48 detects the displacement of the scale 47, which moves in the X and Y directions along with the second fixture 21. This allows the displacement of the second fixture 21 to be detected. Furthermore, since the detection head 48 and the scale 47 are not in contact, particle generation is reduced compared to a contact situation. Furthermore, since the scale 47 moves along with the second fixture 21 rather than the detection head 48, structural complexity can be avoided or reduced compared to a situation where the detection head 48 and the second fixture 21 move together.

[0271] In this embodiment, the scale 47 overlaps with the second jig 21 when viewed from above. This reduces the footprint (the area of ​​the object when viewed from directly above) of the second jig 21 and the scale 47. Furthermore, the detection head 48 overlaps with the scale 47 when viewed from above. This reduces the footprint of the second jig 21, the scale 47, and the detection head 48. Consequently, the substrate bonding apparatus 1 can be miniaturized.

[0272] In this embodiment, the power of the two Z actuators 18 is transmitted to the first clamp 11 via two followers. The two ball nuts 18n are an example of two followers. The two followers correspond one-to-one to the two Z actuators 18 and move in the Z direction along two parallel and vertical straight lines together with the first clamp 11. The two followers can move in the Z direction independently of each other. By adjusting the positions of the two followers in the Z direction through the two Z actuators 18, the posture of the first substrate W1 held by the first clamp 11 can be controlled. In this way, the posture of the first substrate W1 can be stabilized.

[0273] In this embodiment, the flip actuator 16 flips the first substrate W1 held by the first clamp 11. Therefore, the first substrate W1 is held by the first clamp 11 before flipping and is also held by the first clamp 11 when it is joined to the second substrate W2. Therefore, the first substrate W1 can be kept from moving from the first clamp 11 during the period from flipping the first substrate W1 to joining it to the second substrate W2. Furthermore, the two Z actuators 18 not only move the two followers and the first clamp 11 in the Z direction, but also move the flip actuator 16 in the Z direction. Therefore, the posture of the flipped first substrate W1 can be adjusted.

[0274] In this embodiment, the two followers move in the Z direction along two parallel, perpendicular lines along with the first clamp 11. The flip actuator 16 rotates the first substrate W1 about a horizontal line passing through these two lines. The two Z actuators 18 tilt the centerline 11c of the first clamp 11 in the Y direction. The flip actuator 16 tilts the centerline 11c of the first clamp 11 in the X direction. This allows for more flexible adjustment of the posture of the first substrate W1.

[0275] In this embodiment, the first clamp 11 is guided in the Z direction by at least one linear guide 17. This can reduce the mechanical play of the mechanism supporting the first clamp 11, and thus make the posture of the first substrate W1 more stable.

[0276] In this embodiment, the first jig 11 and the second jig 21 are moved relative to each other while the alignment camera 45 is imaging the first fixed reference member 31r and the second fixed reference member 32r. The first fixed reference member 31r does not overlap with the first substrate W1 held by the first jig 11, and the second fixed reference member 32r does not overlap with the second substrate W2 held by the second jig 21. Furthermore, the first display plate 31d of the first fixed reference member 31r is a transparent plate that is permeable to visible light. Therefore, the alignment camera 45, acting as a visible light camera, can image the second fixed reference member 32r through the first fixed reference member 31r, thereby capturing images of the first reference mark 31m and the second reference mark 32m.

[0277] The first reference mark 31m serves as an indirect reference when aligning the first substrate W1 held by the first clamp 11. Similarly, the second reference mark 32m serves as an indirect reference when aligning the second substrate W2 held by the second clamp 21. The first reference mark 31m moves together with the first substrate W1, and the second reference mark 32m moves together with the second substrate W2. Therefore, by adjusting the relative position of the first reference mark 31m and the second reference mark 32m, the relative position of the first substrate W1 and the second substrate W2 can be adjusted. This allows alignment adjustment of the first substrate W1 and the second substrate W2 without imaging the overlapping first and second substrates W1 and W2.

[0278] In this embodiment, the first camera 41 not only captures the first reference mark 31m, but also captures the first alignment mark AM1 of the first substrate W1 held by the first clamp 11. Similarly, the second camera 42 not only captures the second reference mark 32m, but also captures the second alignment mark AM2 of the second substrate W2 held by the second clamp 21. The relative position and angle of the first alignment mark AM1 and the first reference mark 31m can be determined based on the image captured by the first camera 41. Similarly, the relative position and angle of the second alignment mark AM2 and the second reference mark 32m can be determined based on the image captured by the second camera 42. Thus, the first reference mark 31m and the second reference mark 32m can be used to perform alignment adjustment of the first substrate W1 and the second substrate W2.

[0279] In this embodiment, while the first substrate W1 and the second substrate W2 are both flat, the bonding surface WA1 of the first substrate W1 is tilted relative to the bonding surface WA2 of the second substrate W2. In this state, the bonding surface WA1 of the first substrate W1 is partially in contact with the bonding surface WA2 of the second substrate W2. Next, the inclination angle of the bonding surface WA1 of the first substrate W1 relative to the bonding surface WA2 of the second substrate W2 is reduced, thereby increasing the area of ​​the region where the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2 are in contact. During this process, air is discharged from between the bonding surface WA1 of the first substrate W1 and the bonding surface WA2 of the second substrate W2. As a result, bubbles remaining between the two bonded substrates W can be eliminated or reduced. Furthermore, since the first substrate W1 and the second substrate W2 are bonded while being both flat, there is no need for a structure or mechanism that deforms at least one of the first substrate W1 and the second substrate W2.

[0280] In this embodiment, the alignment adjustment of the first substrate W1 and the second substrate W2 is performed in a state where the entire bonding surface WA1 of the first substrate W1 held by the first clamp 11 is parallel to the entire bonding surface WA2 of the second substrate W2 held by the second clamp 21. Therefore, compared with the case where the alignment adjustment is performed in a state where the first substrate W1 and the second substrate W2 are not parallel, the relative position and angle of the first substrate W1 and the second substrate W2 can be adjusted precisely. After the alignment adjustment is performed, the first substrate W1 and the second substrate W2 are bonded in the same manner as described above. Therefore, the first substrate W1 and the second substrate W2 can be bonded with higher precision while eliminating or reducing bubbles remaining between the two bonded substrates W.

[0281] In this embodiment, the first camera 41 images the first alignment mark AM1 on the first substrate W1. If the first alignment mark AM1 on the first substrate W1 has a shape that can be determined in its vertical and horizontal directions, it is determined whether the tilt angle of the first alignment mark AM1 relative to the image generated by the first camera 41 exceeds a first upper limit (e.g., a value greater than 0 and less than 5). If the tilt angle of the first alignment mark AM1 exceeds the first upper limit, the first rotation motor 12 rotates the first substrate W1 and the first clamp 11 to reduce the tilt angle of the first alignment mark AM1 to below the first upper limit. This allows the shape of the first alignment mark AM1 to be determined with greater accuracy based on the image generated by the first camera 41, and the position and angle of the first substrate W1 to be determined with greater accuracy. Consequently, alignment adjustment between two substrates W can be performed with greater precision.

[0282] In this embodiment, the first camera 41 captures the first alignment mark AM1 on the first substrate W1, and the second camera 42 captures the second alignment mark AM2 on the second substrate W2. The control device 3 receives electronic data from the captured images and analyzes and determines the images based on a program stored in the memory 3c. If the second alignment mark AM2 on the second substrate W2 has a shape that allows for perpendicular height and width directions, the control device 3 determines whether the tilt angle of the second alignment mark AM2 relative to the image generated by the second camera 42 exceeds a second upper limit (e.g., a value greater than 0 and less than 5). If the control device 3 determines that the tilt angle of the second alignment mark AM2 exceeds the second upper limit, the control device 3 rotates the second substrate W2 and the second clamp 21 via the second rotation motor 22 to reduce the tilt angle of the second alignment mark AM2 to below the second upper limit. This allows the position and angle of both the first substrate W1 and the second substrate W2 to be determined with higher accuracy.

[0283] In this embodiment, the flip actuator 16 flips the first substrate W1 held by the first clamp 11. Furthermore, at least one Z actuator 18 causes the first clamp 11 and the second clamp 21 to move relative to each other in the Z direction, thereby joining the first substrate W1 held by the first clamp 11 and the second substrate W2 held by the second clamp 21. The first substrate W1 is held by the first clamp 11 before flipping, and is also held by the first clamp 11 when joined to the second substrate W2. Therefore, the first substrate W1 does not need to be moved from the first clamp 11 during the period from the time the first substrate W1 is flipped until the time it is joined to the second substrate W2. As a result, the transportation time of the first substrate W1 and the second substrate W2 can be shortened.

[0284] In this embodiment, horizontal actuators such as the X actuator 27 and the Y actuator 25 move the second clamp 21 horizontally relative to the first clamp 11. The horizontal actuator not only moves the second clamp 21 horizontally, but also moves the first camera 41 horizontally. The first camera 41 photographs the first substrate W1 held and flipped by the first clamp 11. The horizontal actuator also serves as a photographing position adjustment actuator that changes the position photographed by the first camera 41. Therefore, compared with the case where a photographing position adjustment actuator is provided that is different from the horizontal actuator, the components of the substrate bonding device 1 can be reduced.

[0285] In this embodiment, after the first substrate W1 held by the first jig 11 and the second substrate W2 held by the second jig 21 are joined, the second jig 21 is made to hold the first and second substrates W1, and the inspection camera 43 photographs the first and second substrates W1, W2 held by the second jig 21. While photographing, a second first substrate W1 is transported to the first jig 11 by the transport robot TR. Therefore, compared to a case where the second first substrate W1 is transported to the first jig 11 after the joined first and second substrates W1 are removed from the second jig 21, multiple pairs of first and second substrates W1, W2 can be joined in a shorter time.

[0286] In this embodiment, not only is the second first substrate W1 conveyed to the first clamp 11 while the inspection camera 43 is photographing the first and second substrates W1, but the second first substrate W1 held by the first clamp 11 is also flipped while the inspection camera 43 is photographing the first and second substrates W1, W2. Therefore, compared to a case where the second first substrate W1 is flipped after the inspection camera 43 finishes photographing, multiple pairs of first and second substrates W1, W2 can be joined in a shorter time.

[0287] In this embodiment, horizontal actuators such as the X actuator 27 and the Y actuator 25 move the second clamp 21 horizontally relative to the first clamp 11 between a joining position and a photographing position. The joining position is a position where the first substrate W1 held by the first clamp 11 and the second substrate W2 held by the second clamp 21 are joined. The photographing position is a position where the inspection camera 43 photographs the first substrate W1 and the second substrate W2 held by the second clamp 21. The horizontal actuator also serves as a photographing position adjustment actuator that changes the position photographed by the inspection camera 43. Therefore, compared with the case where a photographing position adjustment actuator different from the horizontal actuator is provided, the components of the substrate joining device 1 can be reduced.

[0288] Next, other embodiments will be described.

[0289] The first substrate W1 may not be the upper substrate W but the lower substrate W. That is, the upper substrate W may be the second substrate W2 and the lower substrate W may be the first substrate W1.

[0290] The inspection camera 43 can be fixed to the second frame 28 via a bracket different from the bracket 44 that holds the second narrow field of view camera 42n and the second wide field of view camera 42w. The inspection camera 43 can be fixed to the pedestal 20 via a member other than the second frame 28, such as the first frame 19. For example, the inspection camera 43 can be fixed to the first workbench 13. In this case, compared to a case where the inspection camera 43 is fixed to the second frame 28, the movement distance of the first substrate W1 and the second substrate W2 when placing the first substrate W1 and the second substrate W2 within the range that the inspection camera 43 can capture can be shortened.

[0291] The first camera 41 may not capture the first fixed reference member 31r each time it captures the first substrate W1 held by the first clamp 11. For example, a pre-captured image of the first fixed reference member 31r may be used to determine the position and angle of the first substrate W1 relative to the first fixed reference member 31r. However, because the conditions (such as temperature and humidity) when capturing the first fixed reference member 31r may differ from those when capturing the first substrate W1, it is preferable to capture the first fixed reference member 31r each time it captures the first substrate W1 held by the first clamp 11 in order to more accurately detect the position and angle of the first substrate W1 relative to the first fixed reference member 31r. The same applies to capturing the second fixed reference member 32r.

[0292] If the first alignment mark AM1 is captured before the first substrate W1 is held by the first clamp 11, the first alignment mark AM1 need not be captured while the first substrate W1 is held by the first clamp 11. In other words, if the first clamp 11 holds the first substrate W1 after the position and angle of the first substrate W1 are known in advance, the first alignment mark AM1 need not be captured. In this case, the first camera 41 can be omitted from the bonding unit 2b. The same applies to the second camera 42.

[0293] The actuator mechanism AC may further include one or more piezoelectric actuators disposed on the first worktable 13 and configured to move the first clamp 11 in the Z direction. In this case, the control device 3 can lower the first substrate W1 using the Z actuator 18, maintaining a slight gap between the downward-facing bonding surface WA1 of the first substrate W1 and the upward-facing bonding surface WA2 of the second substrate W2. The control device 3 can then drive the one or more piezoelectric actuators to bring the bonding surface WA1 of the first substrate W1 into contact with the upward-facing bonding surface WA2 of the second substrate W2.

[0294] The substrate bonding apparatus 1 is not limited to an apparatus for bonding two disc-shaped substrates W, but may also be an apparatus for bonding two polygonal substrates W.

[0295] Two or more of all the aforementioned configurations may be combined. Two or more of all the aforementioned steps may be combined.

[0296] The pedestal 20 is an example of a base member having a main surface extending in the horizontal direction. The first frame 19 is an example of a support portion, fixed to the base member and supporting the first clamp 11. The first camera 41 is an example of a first imaging unit, moves in the X and Y directions together with the second clamp 21, and images the first substrate W1. The second camera 42 is an example of a second imaging unit, is fixed in the horizontal direction, and images the second substrate W2. The pair of support bases 15 are examples of a first connecting portion and a second connecting portion provided in the Y direction perpendicular to the Z direction, sandwiching the first substrate W1.

[0297] Although the embodiments of the present invention have been described in detail, these embodiments are merely specific examples for clarifying the technical content of the present invention, and the present invention should not be construed as being limited to these specific examples. The spirit and scope of the present invention are limited only by the claims.

[0298] Description of Reference Numerals 1: Substrate bonding device 1a: outer wall 2: Processing unit 2b: Joint unit 2b1: First Engagement Module 2b2: Second Engagement Module 2c: Cleaning unit 2h: Hydrophilization unit 3: Control device 3a: Computer body 3b: CPU 3c: Memory 3d: peripheral devices 3e: Storage 3f: Reader 3g: communication device 9: Chamber 9p: Next door 9s: Bezel 10: Vibration elimination table 11: First fixture 11c: Centerline 11p: Suction port 11s: First adsorption surface 11v: Valve 12: First rotation motor 13: First workbench 13h: Through hole 14: Support shaft 15: Support base 16: Flip actuator 16c: Inversion Center 17: Linear guide 17b: Slider 17L: Track 18: Z actuator 18c: Centerline 18n: ball nut 18s: Ball screw 19: First Frame 19s: First side frame 19u: First upper frame 20: Pedestal 21: Second clamp 21c: Centerline 21s: Second adsorption surface 22: Second rotation motor 23: Second workbench 23L: Lower workbench 23u: On the workbench 23w: Through window 24: Linear guide 24L: Track 24b: Slider 25: Y actuator 25f: Fixed magnet 25m: Movable magnet 26: Linear guide 26L: Track 26b: Slider 27: X actuator 27f: Fixed magnet 27m: Movable magnet 28: Second Frame 28s: Second side frame 28u: Second upper frame 31L: First fixed line 31b: First support block 31d: First display panel 31m: First benchmark 31p: First fixed point 31r: First fixed reference part 32L: Second fixed line 32b: Second support block 32d: Second display panel 32m: Second benchmark 32p: Second fixed point 41: First Camera 41n: The first narrow field of view camera 41w: The first wide-field camera 42: Second Camera 42n: Second narrow field of view camera 42w: Second widest field of view camera 43: Check the camera 44: Bracket 44h: Through hole 45: Aim at the camera 46: Displacement detector 47: Ruler 47s: Reflective surface 48: Detection head 48e: Luminous part 48i: Interpolator 48m: Main body 48r: Light receiving element 48s: Light Source 48x: X detection head 48y: Y detection head AC: Actuator mechanism AG1: Center of Gravity AG2: Center of Gravity AH1: horizontal axis AH2: horizontal axis AM1: First alignment mark AM2: Second alignment mark AP1: Benchmark AP2: Benchmark AV1: vertical axis AV2: vertical axis CA: Bearer LP: Loading Port LP1: First loading port LP2: Second loading port LP3: Loading port 3 P: Program RM: Removable Media S1 to S8: Steps TH:Robot TP: Transport Path TR: Transport Robot TS: handling system W: substrate W1: first substrate W2: Second substrate WA1: joint surface WA2: Joint surface WB1: Bonding layer WB2: Bonding layer WC1: device layer WC2: device layer WD1: Base material WD2: substrate.

Claims

1. A substrate bonding device, wherein: Equipped with a joining unit, The joining unit comprises: a first clamp holding a first substrate; a second clamp holding a second substrate; an actuator mechanism that moves the first clamp and the second clamp relative to each other, thereby joining the first substrate held by the first clamp and the second substrate held by the second clamp; and The inspection camera captures an image of the first substrate and the second substrate held by the second jig in a state of being bonded to each other.

2. The substrate bonding apparatus according to claim 1, wherein: The first substrate has a first bonding surface, and at least one first alignment mark is formed on the first bonding surface. The second substrate has a second bonding surface, and at least one second alignment mark is formed on the second bonding surface. The inspection camera is an infrared camera, and detects the first alignment mark and the second alignment mark in a state where the first substrate and the second substrate are bonded together.

3. The substrate bonding apparatus according to claim 2, wherein: The substrate bonding device further comprises an outer wall for accommodating the bonding unit. The joining unit further has a chamber in the outer wall that accommodates the first jig, the second jig, and the inspection camera.

4. The substrate bonding apparatus according to claim 2 or 3, wherein: The joining unit further includes a pedestal disposed below the first jig, the second jig, and the inspection camera so as to overlap with the first jig, the second jig, and the inspection camera in a plan view.

5. The substrate bonding apparatus according to claim 1, wherein The substrate bonding apparatus further includes a transfer robot configured to transfer a second first substrate to the first jig when the inspection camera captures an image of the first substrate and the second substrate held by the second jig. The substrate bonding apparatus according to claim 5 , wherein: The actuator mechanism includes a reversing actuator that reverses the second first substrate carried by the carrier to the first fixture and held by the first fixture when the inspection camera images the first substrate and the second substrate held by the second fixture.

7. The substrate bonding apparatus according to claim 5 or 6, wherein: The actuator mechanism also includes a horizontal actuator, which causes the second clamp to move horizontally relative to the first clamp between a joining position and a shooting position, wherein the joining position is a position where the first substrate held by the first clamp and the second substrate held by the second clamp are joined, and the shooting position is a position where the inspection camera shoots the first substrate held by the second clamp and the second substrate.

8. A substrate bonding method, wherein: include: Step a, causing a bonding unit of a substrate bonding device to bond a first substrate and a second substrate; as well as In step b, the bonding unit is configured to inspect the bonded first and second substrates.

9. The substrate bonding method according to claim 8, wherein: The process a comprises: a step of holding the first substrate by a first clamp; a step of holding the second substrate by a second jig; and a step of moving the first clamp and the second clamp relative to each other to thereby bond the first substrate held by the first clamp and the second substrate held by the second clamp; The step b includes the step of causing an inspection camera to capture images of the first substrate and the second substrate held by the second jig after the first substrate and the second substrate are bonded together. The substrate bonding method further includes a step c of transferring a second first substrate to the first jig by a transfer robot while the inspection camera images the first substrate and the second substrate held by the second jig.

Images