Bonding method and bonding device

Abstract

To provide a bonding method and a bonding device which prevent air bubbles from being left between two substrates in a step of bonding the two substrates.SOLUTION: A method for bonding a first substrate 210 and a second substrate 230 includes: forming a protrusion 215 having a greater curvature than other regions of the first substrate at a partial region of the first substrate; measuring the first substrate after the protrusion is formed in the first substrate; positioning the first substrate and the second substrate on the basis of the result of measurement of the first substrate; bringing at least a portion of the protrusion of the first substrate into contact with a portion of a surface of the second substrate after positioning the first substrate and the second substrate; and bonding the first substrate and the second substrate by enlarging a contact region of the first substrate to the second substrate after bringing at least a portion of the protrusion of the first substrate into contact with a portion of the surface of the second substrate.SELECTED DRAWING: Figure 11

Description

[Technical Field]

[0001] The present invention relates to a joining method and a joining device. [Background technology]

[0002] There is a method for manufacturing a laminated substrate in which two substrates are stacked by bonding two substrates together (see, for example, Patent Document 1). Patent Document 1: JP 2012-186243 A

[0003] During the process of bonding two substrates together, air bubbles may remain between the two substrates. Summary of the Invention

[0004] In a first aspect of the present invention, there is provided a bonding method for bonding a first substrate and a second substrate, the bonding method including: a forming step of forming a protrusion having a larger curvature in a partial region of the first substrate than in other regions of the first substrate; a step of measuring the first substrate with the protrusion formed on the first substrate; an alignment step of aligning the first substrate and the second substrate based on the results of measuring the first substrate; a contact step of contacting at least a portion of the protrusion of the first substrate with a portion of a surface of the second substrate after aligning the first substrate and the second substrate; and a bonding step of expanding the contact area of ​​the first substrate with the second substrate and bonding the first substrate and the second substrate together.

[0005] In a second aspect of the present invention, there is provided a bonding apparatus for bonding a first substrate and a second substrate, the bonding apparatus comprising: a first holding unit that adsorbs and holds the first substrate; a forming unit that forms a protrusion having a larger curvature in a partial region of the first substrate than in other regions of the first substrate; a measuring unit that measures the first substrate after the protrusion has been formed on the first substrate; an alignment unit that aligns the first substrate and the second substrate based on the results of measuring the first substrate; and a bonding unit that, after aligning the first substrate and the second substrate, brings at least a portion of the protrusion of the first substrate into contact with a portion of the surface of the second substrate and controls the adsorption force of the first holding unit to expand the contact area of ​​the first substrate with the second substrate, thereby bonding the first substrate and the second substrate.

[0006] The above summary of the invention does not list all of the features of the present invention. Subcombinations of these features may also constitute inventions. [Brief explanation of the drawings]

[0007] [Figure 1] 2 is a schematic plan view of substrates 210 and 230. FIG. [Figure 2] 2 is a flow chart showing a procedure for bonding substrates 210, 230. [Figure 3] FIG. 2 is a schematic cross-sectional view of a substrate holder 220. [Figure 4] FIG. 2 is a schematic cross-sectional view of a substrate holder 240. [Figure 5] FIG. 2 is a schematic cross-sectional view of the joining device 100. [Figure 6] 3A to 3C are schematic cross-sectional views showing the operation of the joining device 100. [Figure 7] 3A to 3C are schematic cross-sectional views showing the operation of the joining device 100. [Figure 8] 3A to 3C are schematic cross-sectional views showing the operation of the joining device 100. [Figure 9] 2A to 2C are schematic cross-sectional views showing the process of bonding substrates 210 and 230. [Figure 10]3A to 3C are schematic cross-sectional views showing the operation of the joining device 100. [Figure 11] 2A to 2C are schematic cross-sectional views showing the process of bonding substrates 210 and 230. [Figure 12] 2A to 2C are schematic cross-sectional views showing the process of bonding substrates 210 and 230. [Figure 13] 2A to 2C are schematic cross-sectional views showing the process of bonding substrates 210 and 230. [Figure 14] 1A to 1C are schematic cross-sectional views showing the progression of a bonding wave. [Figure 15] 1A to 1C are schematic cross-sectional views showing the progression of a bonding wave. [Figure 16] 1A to 1C are schematic cross-sectional views showing the progression of a bonding wave. [Figure 17] FIG. 2 is a schematic cross-sectional view of a substrate holder 260. [Figure 18] 10A and 10B are schematic cross-sectional views showing a bonding process using a substrate holder 260. FIG. [Figure 19] 1A to 1C are schematic cross-sectional views showing the progression of a bonding wave. [Figure 20] 1A to 1C are schematic cross-sectional views showing the progression of a bonding wave. [Figure 21] 10A and 10B are schematic cross-sectional views showing a bonding process using a substrate holder 260. FIG. [Figure 22] 10A and 10B are schematic cross-sectional views showing a bonding process using a substrate holder 260. FIG. [Figure 23] 10A and 10B are schematic cross-sectional views showing a bonding process using a substrate holder 260. FIG. [Figure 24] 10A and 10B are schematic cross-sectional views showing a bonding process using a substrate holder 260. FIG. [Figure 25] FIG. 2 is a schematic cross-sectional view of a substrate holder 270. [Figure 26] FIG. 2 is a schematic cross-sectional view of a substrate holder 270. [Figure 27] FIG. 2 is a schematic cross-sectional view of a substrate holder 290. [Figure 28] FIG. 2 is a perspective view of a protruding member 280. [Figure 29] 10 is a flow chart showing another joining procedure. [Figure 30]10A and 10B are schematic cross-sectional views showing a bonding process using substrate holders 260 and 290. [Figure 31] 10A and 10B are schematic cross-sectional views showing a bonding process using substrate holders 260 and 290. [Figure 32] 10 is a graph illustrating the bonding process using the substrate holder 270. [Figure 33] 10A and 10B are schematic cross-sectional views showing a bonding process using substrate holders 260 and 290. [Figure 34] 10A and 10B are schematic cross-sectional views showing a bonding process using substrate holders 260 and 290. [Figure 35] 10A-10C show examples of application of the bonding procedure to the substrate holder used. [Figure 36] 10 is a schematic cross-sectional view showing a bonding process using substrate holders 260 and 296. FIG. [Figure 37] 10 is a schematic cross-sectional view showing a bonding process using substrate holders 260 and 296. FIG. [Figure 38] FIG. 3 is a schematic cross-sectional view of a protruding member 301. [Figure 39] FIG. 3 is a schematic cross-sectional view of a protruding member 302. [Figure 40] FIG. 3 is a schematic cross-sectional view of a protruding member 303. [Figure 41] FIG. 3 is a schematic cross-sectional view of a protruding member 304. [Figure 42] FIG. 5 is a schematic cross-sectional view of a substrate holder 501. [Figure 43] FIG. 5 is a schematic cross-sectional view of a substrate holder 502. [Figure 44] FIG. 5 is a schematic cross-sectional view of a substrate holder 503. [Figure 45] FIG. 5 is a schematic cross-sectional view of a substrate holder 504. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention will be described below through embodiments of the invention. The following embodiments do not limit the scope of the invention. Not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0009] 1 is a schematic plan view of substrates 210 and 230 that are stacked and bonded to each other. Each of the substrates 210 and 230 has scribe lines 211 and 231, alignment marks 213 and 233, and circuit regions 214 and 234. A plurality of alignment marks 213 and 233 and a plurality of circuit regions 214 and 234 are provided.

[0010] The alignment marks 213, 233 are an example of a structure formed on the surface of the substrates 210, 230, and in the illustrated example, are arranged to overlap the scribe lines 211, 231 arranged between the circuit regions 214. The alignment marks 213, 233 are used as indexes for aligning the substrates 210, 230 with each other when bonding the two substrates 210, 230 together.

[0011] A plurality of circuit regions 214, 234 having the same structure are periodically arranged on the surface of the substrate 210, 230. Each of the circuit regions 214, 234 is provided with structures such as semiconductor devices, wiring, and protective films formed by photolithography or the like. Connection portions such as pads and bumps that serve as connection terminals when electrically connecting the substrate 210 to another substrate 210, a lead frame, or the like are also arranged in the circuit regions 214, 234. The connection portions are also an example of structures formed on the surface of the substrate 210.

[0012] 2 is a flow chart showing the procedure for bonding the substrates 210 and 230. First, the substrates 210 and 230 to be bonded together are held by holding members such as substrate holders 220 and 240 (step S101). This protects the substrates 210 and 230 and makes them easy to handle.

[0013] 3 is a schematic cross-sectional view of the substrate holder 220 that holds one of the substrates 210. The substrate holder 220 has a main body portion 229 and a protruding member 250.

[0014] The main body 229 has a holding surface 221, an air passage 222, and a recess 223. The holding surface 221 has a flat surface formed on the upper surface of the main body 229 in the figure, and contacts the back surface of the substrate 210.

[0015] The ventilation path 222 has at one end a plurality of air intake holes that open to the holding surface 221. The other end of the ventilation path 222 is selectively coupled via a control valve 124 to a negative pressure source 125 and an open end 126 provided outside the substrate holder 220.

[0016] The control valve 124 selectively connects the air passage 222 to the negative pressure source 125 or the open end 126 under the control of a control unit 150 of the bonding apparatus 100, which will be described later. When the control valve 124 connects the air passage 222 to the negative pressure source 125, a negative pressure acts on the opening of the holding surface 221, and the substrate 210 placed on the substrate holder 220 is adsorbed. When the control valve 124 connects the air passage 222 to the open end 126, the suction force of the holding surface 221 is released, and the substrate 210 is released from the substrate holder 220.

[0017] The recess 223 is formed approximately in the center of the holding surface 221. The recess 223 accommodates the protrusion member 250 inside, recessed from the holding surface 221. The protrusion member 250 has a flat bottom surface, and is fixed to the bottom surface of the recess 223 by fixing means such as adhesive, double-sided tape, magnetic force, screws, or a fitting structure. The protrusion member 250 also has an abutment portion 251, which protrudes upward approximately in the center and has the upper end surface in the figure as the abutment surface against the substrate 210.

[0018] In the illustrated example, the abutting portion 251 has a cylindrical shape. A height A from the bottom surface of the protruding member 250 to the upper end of the abutting portion 251 is greater than a depth B of the recess 223, so that the upper end of the abutting portion 251 protrudes from the surface of the holding surface 221. Therefore, when the substrate 210 is adsorbed to the holding surface 221, the upper end of the abutting portion 251 abuts against the lower surface of the substrate 210 and pushes up a central region C of the substrate 210 from the lower surface toward the upper surface, i.e., in a direction in which the region C moves away from the main body portion 229. As a result, a protruding portion 215 that protrudes with a larger curvature than other regions of the substrate 210 is formed in the central portion of the substrate 210 that is adsorbed to the holding surface 221 and held by the substrate holder 220. In other words, the protruding member 250 is an example of a forming portion that forms the protruding portion 215 by abutting against a partial region of the substrate 210 held by the holding surface 221.

[0019] The curvature of the protruding portion 215 formed on a part of the substrate 210 by the protruding member 250 is not necessarily constant throughout the entire protruding portion 215, and at least a portion of the protruding portion 215 has a curvature greater than that of the region of the substrate 210 other than the protruding portion 215. When the region of the substrate 210 other than the protruding portion 215 is flat, i.e., when the curvature of that region is zero, in the substrate 210 on which the protruding portion 215 is formed by the protruding member 250, only the protruding portion 215 of the flat substrate 210 has a shape having a curved portion.

[0020] Furthermore, if regions of the substrate 210 other than the protruding portion 215 are also curved, the local curvature of the protruding portion 215 may be smaller than the curvature of other regions of the substrate 210. For example, if the shape of the protruding portion 215 includes part of a cone, the curvature of the portion corresponding to the side surface of the cone may be zero. Furthermore, if, for example, the peripheral portion of the substrate 210 is significantly curved toward the back surface, the curvature of the protruding portion 215 may be smaller than the curvature of the peripheral portion. However, in either case, the entire protruding portion 215 has a shape that protrudes from a virtual continuous plane or curved surface formed by the region of the substrate 210 other than the protruding portion 215.

[0021] When viewed in a cross section of the protrusion 215 cut along a plane that passes through the apex of the protrusion 215 and is along the thickness direction of the substrate 210, the curvature of the surface at least at the tip of the protrusion 215 is greater than the curvature of the region other than the central portion of the substrate 210. The curvature of the surface of the tip is a curvature when, when the tip of the protrusion 215 comes into contact with the other substrate 230, the area and shape of the contact region are such that no air bubbles are generated or trapped between the tip and the other substrate 230 to the extent that they would cause poor bonding.

[0022] The height D of the protrusion 215 is the height of the apex of the protrusion 215 when the surface of the substrate 210 in an area other than the center is used as the reference, and roughly corresponds to the amount of protrusion of the abutment portion 251 from the holding surface 221.

[0023] 4 is a schematic cross-sectional view of a substrate holder 240 that holds another substrate 230 to be bonded to the substrate 210. The substrate holder 240 has a holding surface 241 and a main body portion 249 in which an air passage 242 is formed.

[0024] A holding surface 241 of the substrate holder 240, which is generally flat, is provided with a plurality of openings that communicate with an air passage 242. One end of the air passage 242 is selectively coupled via a control valve 144 to a negative pressure source 145 and an open end 146 provided outside the substrate holder 240.

[0025] The control valve 144 , like the control valve 124 , is controlled by a control unit 150 of the bonding device 100 , which will be described later, and selectively connects the air passage 242 to a negative pressure source 145 or an open end 146 .

[0026] Referring again to FIG. 2, as described above, the substrates 210 and 220 held by the substrate holders 220 and 240, respectively, are carried into the bonding apparatus 100 together with the substrate holders 220 and 240 (step S102).

[0027] Fig. 5 is a schematic diagram showing the structure of the bonding apparatus 100. Fig. 5 also shows the state immediately after the substrates 210 and 230 are carried in at step S102.

[0028] The bonding apparatus 100 includes a frame 110 , a fixed stage 121 , a moving stage 141 , and a control unit 150 .

[0029] The fixed stage 121 is fixed facing downward to the top plate 113 of the frame body 110, and has a holding function such as a vacuum chuck or an electrostatic chuck, and adsorbs and holds the substrate holder 220. The substrate holder 220 holding the substrate 210 is carried into the fixed stage 121 so that the surface of the substrate 210 faces downward.

[0030] Additionally, an upper microscope 122 and an upper activation device 123, which are fixed facing downward in the figure, are disposed on the lower surface of the top plate 113, to the side of the fixed stage 121. The upper microscope 122 can observe the upper surface of the substrate 230 on the movable stage 141, which is disposed opposite the fixed stage 121. The upper activation device 123 generates plasma that cleans and activates the upper surface of the substrate 230 held on the movable stage 141.

[0031] An X-direction drive unit 131, a Y-direction drive unit, and a moving stage 141 are stacked on the upper surface of the bottom plate 111 of the frame body 110 in the figure. The substrate holder 240 holding the substrate 230 is carried onto the upper surface of the moving stage 141 so that the surface of the substrate 230 faces upward.

[0032] The X-direction driving unit 131 moves in the direction indicated by the arrow X in the figure, parallel to the bottom plate 111. The Y-direction driving unit 132 moves in the direction indicated by the arrow Y in the figure, parallel to the bottom plate 111, on the X-direction driving unit 131. By combining the operations of the X-direction driving unit 131 and the Y-direction driving unit 132, the moving stage 141 can move two-dimensionally, parallel to the bottom plate 111.

[0033] A Z-direction driver 133 is disposed between the Y-direction driver 132 and the movable stage 141. The Z-direction driver 133 moves the movable stage 141 relative to the Y-direction driver 132 in a direction perpendicular to the bottom plate 111, as indicated by the arrow Z. This allows the movable stage 141 to approach the fixed stage 121. The amount of movement of the movable stage 141 by the X-direction driver 131, the Y-direction driver 132, and the Z-direction driver 133 is measured with high precision using an interferometer or the like.

[0034] A lower microscope 142 and a lower activation device 143 are mounted on the side of the movable stage 141 on the upper surface of the Y-direction driver 132 in the figure. The lower microscope 142 moves together with the Y-direction driver 132 to observe the lower surface of the substrate 210 facing downward and held on the fixed stage 121. The lower activation device 143 moves together with the Y-direction driver 132 to generate plasma that cleans and activates the lower surface in the figure of the substrate 210 held on the fixed stage 121.

[0035] Alternatively, an activation device in place of the upper activation device 123 and the lower activation device 143 may be provided at a location separate from the bonding device 100 , and the substrates 210 and 230 that have been activated in advance may be carried into the bonding device 100 .

[0036] The bonding apparatus 100 further includes a control unit 150. The control unit 150 controls the operations of the X-direction driving unit 131, the Y-direction driving unit 132, the Z-direction driving unit 133, the upper activation device 123, and the lower activation device 143.

[0037] Prior to bonding the substrates 210 and 230, the control unit 150 calibrates the relative positions of the upper microscope 122 and the lower microscope 142 in advance. Calibration of the upper microscope 122 and the lower microscope 142 can be performed, for example, by focusing the upper microscope 122 and the lower microscope 142 on a common focal point F and having them observe each other. Alternatively, a common standard index may be observed by the upper microscope 122 and the lower microscope 142.

[0038] Referring again to Figure 2, for each of the substrates 210, 230 loaded as described above, the control unit 150 moves the moving stage 141 as shown in Figure 6 to observe the opposing substrates 210, 230 using the upper microscope 122 and the lower microscope 142, thereby measuring the positions of multiple alignment marks 213, 233 (step S103).

[0039] Because the relative positions of the upper microscope 122 and the lower microscope 142 have been calibrated in advance, this measurement allows for accurate detection of the relative positions of the substrates 210 and 230. At this stage, the substrate 210 observed by the lower microscope 142 is held on the fixed stage 121 while being held by a substrate holder 220 having a protrusion member 250. Therefore, the lower microscope 142 observes the substrate 210 with the protrusion 215 formed thereon, and detects the position of the alignment mark 213 on the surface of the substrate 210 including the protrusion 215.

[0040] In this way, the protrusion 215 is formed on the substrate 210 by the protruding member 250 before detecting the position of the alignment mark 213, and the position of the alignment mark 213 is detected with the protrusion 215 formed. This makes it possible to prevent displacement due to deformation in the central part of the substrate 210 after detecting the position of the alignment mark, unlike when the protrusion 215 is formed on the substrate 210 after detecting the position of the alignment mark 213. Therefore, it is possible to prevent a decrease in alignment accuracy.

[0041] Furthermore, since the protrusion 215 is formed on the substrate 210 during the operation of holding the substrate 210 on the substrate holder 220, an increase in labor hours required to form the protrusion 215 can be avoided, unlike a bonding device that holds the substrate 210 and then presses a part of the substrate 210 to form the protrusion 215.

[0042] If the protrusion 215 is formed on the substrate 210 after detecting the position of the alignment mark 213, the position of the alignment mark 213, particularly in the central portion, will deviate from the detected position due to deformation of the central portion of the substrate 210 caused by the formation of the protrusion 215. Furthermore, when a pressing force is applied to the central portion of the substrate 210 to form the protrusion 215, the region other than the central portion is pulled by the pressing force, and the position of the region other than the central portion will deviate from the position at which the alignment mark 213 was detected. This reduces the reliability of the position information and also reduces the alignment accuracy based on the position information.

[0043] In other words, as long as the procedure of forming the protrusion 215, detecting the position of the alignment mark 213, and then aligning the substrates 210, 230 is observed, the protrusion 215 may be formed using equipment other than the substrate holder 220, and the substrates 210, 230 may be stacked on top of each other. An example of such equipment is a stage device equipped with a push rod that protrudes or retracts from the center of the holding surface.

[0044] The control unit 150 calculates the direction and amount of movement of the moving stage 141 required for aligning the substrates 210 and 230 based on the detected relative position information of the substrates 210 and 230 .

[0045] 7, the control unit 150 activates the surfaces of the substrates 210 and 230 by scanning the moving stage 141 while operating the upper activation device 123 and the lower activation device 143 (step S104). When the activated surfaces of the substrates 210 and 230 are brought into contact with each other, they can be bonded to each other without the need for an intervening material such as an adhesive, or without processing such as welding or pressure bonding.

[0046] Next, the control unit 150 moves the moving stage 141 based on the information calculated earlier in step S103, and aligns the substrates 210 and 230 with each other (step S105), as shown in Fig. 8. Fig. 9 is a schematic cross-sectional view showing the state of the substrates 210 and 230 aligned in the bonding apparatus 100.

[0047] At this stage, the control unit 150 controls the control valve 144 to connect the ventilation path 242 of the substrate holder 240 held on the moving stage 141 to the negative pressure source 145. As a result, the substrate 230 is adsorbed onto the holding surface 241.

[0048] The control unit 150 also controls the control valve 124 to connect the ventilation path 222 of the substrate holder 220 held by the fixed stage 121 to the negative pressure source 125. As a result, the substrate 210 is adsorbed onto the holding surface of the substrate holder 220.

[0049] 10, the control unit 150 operates the Z direction driving unit 133 to raise the moving stage 141. This causes the substrate 230 to rise, and eventually the substrates 210 and 230 come into contact with each other.

[0050] 11 is a schematic cross-sectional view showing a state in which the substrates 210 and 230 begin to come into contact with each other in the bonding apparatus 100. The substrate 210 held by the fixed stage 121 has a protrusion 215 that protrudes downward in the figure. Therefore, when the movable stage 141 is raised and the substrates 210 and 230 approach each other, the protrusion 215 first comes into contact with the surface of the substrate 230.

[0051] In other words, because the protrusions 215 are higher than other regions of the substrate 210, the tips of the protrusions 215 are sure to be the first to come into contact with the surface of the substrate 230 out of the entire area of ​​the lower surface of the substrate 210. At this time, it is preferable to bring the tips of the protrusions 215 into contact with the center of the surface of the substrate 230. Because the surfaces of the substrates 210 and 230 have already been activated in step S104, a joining starting point 209 is formed at the contact point of the substrates 210 and 230, where parts of the substrates 210 and 230 are joined by contact (step S106: FIG. 2).

[0052] The bonding initiation point 209 is a contact region where the substrates 210, 230 come into contact with each other, and is a contact region formed when bonding begins. The bonding initiation point 209 may be a region having an area. The bonding initiation point of a pair of substrates 210, 230 to be bonded is formed when part of the substrate 210 is pressed against part of the substrate 230, thereby forcing out the atmosphere or the like sandwiched between the substrates 210, 230 and bringing the substrates 210, 230 into direct contact with each other.

[0053] This contact causes the contact areas of the two activated substrates 210, 230 to bond through chemical bonds such as hydrogen bonds. After partially contacting the two substrates 210, 230, the control unit 150 maintains the two substrates 210, 230 in contact with each other. At this time, the contact area may be widened by pressing the substrates 210, 230 together to increase the area of ​​the contacted portion.

[0054] Furthermore, the control unit 150 controls the control valves 124, 144 to connect the ventilation paths 222, 242 of the substrate holders 220, 240 to the negative pressure source 125. Therefore, the substrates 210, 230 are attracted to the substrate holders 220, 240, respectively, and contact between the substrates 210, 230 is prevented at portions other than the joining starting point 209.

[0055] After a predetermined time has passed while maintaining the contact state, a bonding force large enough to prevent misalignment between the substrates 210 and 230 is secured between the two substrates 210. As a result, a bonding starting point is formed at the contacting portion of the substrates 210 and 230.

[0056] Next, the control unit 150 switches the control valve 124 on the fixed stage 121 side to connect the open end of the ventilation path 222 of the substrate holder 220 to atmospheric pressure. This releases the substrate 210 from the substrate holder 220 (step S107), and the substrates 210 and 230 are autonomously bonded to each other due to intermolecular forces between the activated surfaces, etc.

[0057] 12, the bonded contact area of ​​the substrates 210, 230 gradually expands from the bonding starting point 209 toward the radially outer side of the substrates 210, 230. This generates a bonding wave that gradually expands the bonding area, and the bonding of the substrates 210, 230 progresses (step S108).

[0058] FIG. 13 is a schematic cross-sectional view showing the state where the bonding wave of the substrates 210 and 230 has completed its progression, and is shown from the same perspective as FIGS. 11 and 12. As shown, the substrates 210 and 230 are in contact with each other over their entire surfaces and are further bonded together. This completes the bonding of the substrates 210 and 230 (step S109), and the two substrates 210 and 220 become an integrated laminated substrate 201. As described above, the bonding apparatus 100 includes a movable stage 141 and a fixed stage 121, which are holders for holding the two substrates 210 and 230, including the substrate 210 having the protrusion 215 formed thereon. The protrusion 215 of one substrate 210 is brought into contact with the other substrate 230 to form a bonding starting point 209. The contact area is then expanded from the bonding starting point 209 to form a bonded portion that bonds the substrates 210 and 230.

[0059] The suction of the substrate 210 by the substrate holder 240, which is attached to the fixed stage 121 on the upper side in the drawing, has already been released in step S106. Therefore, the formed laminated substrate 201 is held by the substrate holder 240, which is held by the movable stage 141. Thereafter, the laminated substrate 201 is carried out from the bonding apparatus 100 (step S110). The laminated substrate 201 may be carried out alone by first releasing the hold by the substrate holder 240, or the laminated substrate 201 may be carried out together with the substrate holder 240 while still held by the substrate holder 240, and then the laminated substrate 201 may be separated from the substrate holder 240.

[0060] In the above example, the substrates 210 and 230 having the circuit region 214 and the like are aligned and bonded, as in the substrates 210 and 230 shown in Fig. 1. Alternatively, a glass substrate and a semiconductor substrate, etc., on which the circuit region 214 and the like are not formed, may be bonded using the bonding apparatus 100. In this case, the position measurement in step S103 and the alignment in step S105 may be omitted in the bonding procedure shown in Fig. 2.

[0061] 14, 15, and 16 are diagrams illustrating the misalignment between substrates 210 and 230 that occurs as the bonding wave advances from bonding starting point 209 toward the outer periphery during bonding of substrates 210 and 230. These figures show an enlarged view of the boundary K between the bonded and non-bonded regions of substrates 210 and 230, i.e., the vicinity of the tip of the bonding wave, in substrates 210 and 230 during the bonding process.

[0062] The misalignment refers to a deviation from a predetermined relative position between corresponding alignment marks 213 or corresponding connecting portions between the two substrates 210 and 230. If the amount of misalignment is greater than a threshold, the connecting portions will not contact each other or will not have proper electrical continuity, or a predetermined bonding strength will not be obtained between the connecting portions.

[0063] 14, in the vicinity of boundary K, substrate 210, which has been released from the hold by substrate holder 220, undergoes deformation in which the lower surface side in the figure expands and the upper surface side in the figure contracts. Furthermore, as shown in FIG. 15, when the position of boundary K moves on substrates 210 and 230, the location where the above-mentioned deformation occurs also moves together with boundary K.

[0064] When the substrates 210 and 230 that have come into contact with each other while undergoing the above-described deformation are bonded to each other, the expansion of the substrate 210 is fixed by being bonded to the substrate 230, and it appears as if the substrate 210 has expanded relative to the substrate 230. For this reason, a positional deviation corresponding to the amount of expansion of the substrate 210 occurs between the lower substrate 230 held by the substrate holder 240 and the upper substrate 210 released from the substrate holder 220, as shown by the deviation indicated by the dotted line in the figure.

[0065] Furthermore, as shown in FIG. 16, the above-described misalignment accumulates as the boundary K approaches the outer periphery of the substrates 210 and 230, and the misalignment becomes larger as the boundary K approaches the outer periphery.

[0066] 17 is a schematic cross-sectional view of a substrate holder 260 provided as a measure against misalignment that occurs during the bonding process as described above. The substrate holder 260 has a main body 269 including a holding surface 261 and an air passage 262.

[0067] The holding surface 261 of the substrate holder 260 has a cross-sectional shape whose height gradually increases from the periphery to the center. In the illustrated example, the cross-sectional shape gradually increases in thickness from the periphery to the center. This allows the holding surface 261 to have, for example, a spherical surface. The holding surface 261 also has a plurality of openings that communicate with an air passage 262. One end of the air passage 262 is connected to a negative pressure source 145 and an open end 146 provided outside the substrate holder 260 via a control valve 144. The shape of the holding surface 261 is not limited to a spherical surface, and may be a non-rotating body shape such as a paraboloid, which is a curved surface obtained by rotating a parabola around its axis of symmetry, or a paraboloid, which is a part of the curved surface, or a cylindrical surface, which is the outer periphery of a cylinder cut along its central axis.

[0068] Under the control of control unit 150, control valve 144 connects air passage 242 to negative pressure source 145, whereby substrate 230 is adsorbed onto substrate holder 260. Because holding surface 261 of substrate holder 260 is curved, substrate 230 adsorbed onto substrate holder 260 curves to follow the shape of holding surface 261.

[0069] When the substrate 230 is attracted to the holding surface 261 of the substrate holder 260, the front surface of the substrate 230, which is the upper surface in the drawing, is deformed and expanded in the planar direction from the center toward the periphery, compared to the center E in the thickness direction of the substrate 210, which is indicated by the dashed line in the drawing. Also, the back surface of the substrate 230, which is the lower surface in the drawing, is deformed and contracted in the planar direction from the center toward the periphery of the substrate 230.

[0070] 18 is a schematic cross-sectional view showing a case where a substrate holder 260 is used to hold a substrate 230 on the moving stage 141 side in the bonding apparatus 100. The illustrated state corresponds to the stage where bonding starting points 209 are formed on the substrates 210 and 230 in step S106 shown in FIG.

[0071] Substrate 210 held by substrate holder 220 on the upper side in the figure has a localized protrusion 215 formed by contact portion 251 of protruding member 250. Therefore, when substrates 210 and 230 are brought into contact with each other, joining starting point 209 is more reliably formed at a point approximately in the center of protrusion 215 than when holding surface 261 of substrate holder 260 is flat.

[0072] Next, the substrate 210 is released from the substrate holder 220, and a bonding wave is caused to propagate between the substrates 210 and 230, as shown in FIG. 19 (step S108: FIG. 2).

[0073] As shown in the figure, the magnification of the upper surface of substrate 230 held by substrate holder 260 having raised holding surface 261 is increased by following the curved shape of holding surface 261. Therefore, when substrate 210 is released from substrate holder 240 and substrate 210 is bonded to substrate 230 while deforming, the deformation of substrate 210 is offset by the curved deformation of substrate 230, and laminated substrate 201 can be formed without misalignment between substrates 210 and 230.

[0074] The above magnification is a value obtained by dividing the difference (X1-X0) by the distance X0 when a structure located at a distance X0 from the center of the substrate in the design value is located at a distance X1 from the center of the actually manufactured substrate. The magnification is expressed in units of ppm (Parts Per Million), for example.

[0075] Furthermore, in the above example, the substrate holder 260 is used in which the center of the holding surface 261 is raised, but by using a substrate holder 260 in which the center of the holding surface 261 is recessed, it is also possible to shrink the surface of the held substrate 230 and reduce the magnification. This makes it possible to adjust the substrate 230 to fit the circuit area 214 of the substrate 210, thereby preventing misalignment, if it is smaller than the design specifications.

[0076] The amount of change in magnification that occurs during the bonding process is also affected by the height of the protrusion 215 formed on the substrate 210. Therefore, the curvature of the substrate holder 240 that holds the opposing substrate 230 may be adjusted depending on the amount by which the protrusion member 250 of the substrate holder 220 protrudes from the holding surface 221. More specifically, for example, when using a substrate holder 240 having a protrusion member 250 with a greater height, a substrate holder 240 with a greater curvature and a protruding center may be selected and used.

[0077] 20 is a diagram illustrating another countermeasure against misalignment that occurs during the bonding process. The state shown in the figure is a state in which a bonding wave is propagating between substrates 210 and 230 (step S108: FIG. 2).

[0078] In the illustrated method, the lower substrate 230 is held by a substrate holder 240 having a flat holding surface 241, and when the upper substrate 210 is released from the substrate holder 220, the lower substrate 230 is also released from the substrate holder 240. Due to the pulling force from the upper substrate 210, the lower substrate 230 rises up from the substrate holder 240 and curves. As a result, the shape of the surface of the lower substrate 230 changes so that it stretches, and the difference in the amount of stretch with respect to the surface of the upper substrate 210 becomes smaller by the amount of this stretch. Therefore, misalignment caused by different amounts of deformation between the two substrates 210 and 230 is suppressed.

[0079] In other words, by adjusting the bending amount, i.e., the amount of elongation and deformation, of the substrate 230, it is possible to reduce misalignment due to the difference in magnification between the substrates 210 and 230. In this way, even when the substrate holder 240 having the flat holding surface 241 is used, it is possible to suppress misalignment of the substrates 210 and 230.

[0080] When releasing the holding by both substrate holders 220, 240, by actively maintaining the substrates 210, 230 in contact at the position where the joining starting point 209 is to be formed until the joining strength of the substrates 210, 230 becomes sufficiently high, it is possible to prevent the joining starting point 209 from being formed in an unexpected position on the substrates 210, 230 and to prevent air bubbles from remaining in the laminated substrate 201. After the joining of the substrates 210, 230 is completed in step S109 (FIG. 2), the laminated substrate 201 may be held again by either of the substrate holders 220, 240.

[0081] During the overlapping process, when an adsorption force is applied to the substrate 210 from above in the figure in the area near the boundary K where deformation of the substrate 210 occurs, a larger deformation occurs in the substrate 210 than would occur if no correction were made.

[0082] When releasing the substrate 230 for the purpose of correction, the holding force may be weakened instead of being completely eliminated. In this way, by adjusting the holding force of the substrate 230 by the substrate holder 240, the magnification of the substrate 230 can also be adjusted, and positional deviation due to a difference in magnification with the substrate 210 can be corrected.

[0083] Figures 21, 22, 23, and 24 are diagrams showing other methods for bonding substrates 210, 230 using bonding apparatus 100 shown in Figure 5, substrate holder 220 shown in Figure 3, and substrate holder 260 shown in Figure 17. Duplicate individual descriptions of the components used will be omitted.

[0084] 21, a substrate holder 220 carrying a substrate 210 into the bonding apparatus 100 is held by a movable stage 141. A substrate holder 260 carrying a substrate 230 into the bonding apparatus 100 is held by a fixed stage 121.

[0085] Next, after position measurement (step S103), substrate activation (step S104), and substrate alignment (step S105), the substrate 210 on which the protrusion 215 is formed is raised by the moving stage 141 to form the bonding starting point 209 (step S106), as shown in Fig. 22. Furthermore, as shown in Fig. 23, the substrate 210 is released from the substrate holder 220 (step S107), and the bonding wave is allowed to proceed (step S108).

[0086] As the bonding wave progresses in the substrates 210 and 230, the substrate 210, which is released from the substrate holder 220 located on the lower side in the figure, is bonded to the substrate 230 held by the substrate holder 240 on the upper side in the figure, thereby forming a laminated substrate 201, as shown in Figure 24. In this way, in the bonding apparatus 100, the lower substrate 210 can also be released to form the laminated substrate 201.

[0087] 25 is a schematic cross-sectional view of another substrate holder 270 having a flat holding surface 271. The figure shows a state in which the substrate holder 270 holds the substrate 210 and is further held by the fixed stage 121.

[0088] Substrate holder 270 has a main body 279 and protrusion members 250. The shapes of protrusion members 250 and recesses 273 in holding surface 271 that accommodate protrusion members 250 are the same as protrusion members 250 and recesses 223 of substrate holder 220 shown in Figure 3, so redundant explanations will be omitted.

[0089] The main body 279 has two independent ventilation paths 272, 274. One of the ventilation paths 272 has a plurality of openings arranged on the outer periphery of the holding surface 271. The other end of the ventilation path 272 is connected via a control valve 124 to a negative pressure source 125 and an open end 126 provided outside the substrate holder 270. The control valve 124 selectively connects the ventilation path 272 to the negative pressure source 125 or the open end 126 under the control of the control unit 150 of the bonding apparatus 100.

[0090] When the control valve 124 connects the ventilation path 272 to the negative pressure source 125, negative pressure acts on the opening of the holding surface 271, and the substrate 210 is adsorbed to the outer periphery of the holding surface 271. When the control valve 124 connects the ventilation path 272 to the open end 126, the adsorption of the substrate 210 to the holding surface 271 of the substrate holder 270 is released.

[0091] The other ventilation path 274 has a plurality of openings arranged on the holding surface 271 around the recess 273 that accommodates the protrusion member 250. The other end of the ventilation path 274 is coupled via a control valve 127 to a negative pressure source 128 and an open end 129 that are provided outside the substrate holder 270. The control valve 127 selectively connects the ventilation path 274 to the negative pressure source 128 or the open end 129 under the control of the control unit 150 of the bonding apparatus 100.

[0092] When the control valve 127 connects the ventilation path 274 to the negative pressure source 128, negative pressure acts on the opening of the holding surface 271, and the substrate 210 is adsorbed to the holding surface 271 around the recess 273. When the control valve 127 connects the ventilation path 274 to the open end 129, the adsorption of the substrate 210 around the recess 273 is released.

[0093] In the stage of holding the substrate 210 on the substrate holder 270 (step S101: FIG. 2), both of the ventilation paths 272, 274 are connected to the negative pressure sources 125, 129, and the substrate 210 is adsorbed by the entire holding surface 271. As a result, a protrusion 215 is formed on the substrate 210 in the region T where the abutting portion 251 abuts.

[0094] 26 is a diagram showing the next step, which is executed after the step (step S101) in which the substrate holder 270 holds the substrate 210 and before the step (step S103) in which position measurement of the substrate 210 is started.

[0095] Before starting to measure the position of the alignment mark 213 on the substrate 210, the control unit 150 may control the control valve 127 to connect the air passage 274 to the open end 129. This eliminates the suction force around the protruding member 250 in the substrate holder 270, and the area of ​​the substrate 210 that is no longer suctioned moves away from the holding surface 271.

[0096] Therefore, the curvature at the tip of protrusion 215 of substrate 210 decreases, and the amount of deformation of the surface of side substrate 210, which is the lower surface in the figure, also decreases, thereby mitigating the deformation of the surface at the center of substrate 210 caused by forming protrusion 215. However, the step of connecting air vent 274 to open end 129 is not essential, and the measurement in step S103 may be started while air vent 274 is still connected to negative pressure source 145.

[0097] In this state, position measurement (step S103) is performed on the alignment mark 213. This reduces the difference in the position of the alignment mark 213 at the center of the substrate 210 between when the substrate 210 is held by the holding surface 271, i.e., when the protrusion 215 is formed at the center of the substrate 210, and when the substrate 210 is released from the holding surface 271 and bonded to the substrate 230, thereby improving the alignment accuracy of the substrates 210 and 230.

[0098] 27 is a schematic cross-sectional view of another substrate holder 290. The substrate holder 290 has a main body 299 and a protruding member 280.

[0099] The main body 299 has a holding surface 291, ventilation paths 292 and 294, and a recess 293. The holding surface 291 has a flat surface on the upper surface of the main body 299 in the figure. In addition, a recess 293 recessed from the holding surface 291 is provided in the center of the holding surface 291. Furthermore, the main body 299 has a plurality of ventilation paths 292 and 294 penetrating through in the thickness direction.

[0100] One of the ventilation paths 292 has a plurality of openings distributed over the entire area except for the central portion of the holding surface 291. The other end of the ventilation path 292 is coupled via a control valve 144 to a negative pressure source 145 and an open end 146 provided outside the substrate holder 290. The control valve 124 selectively connects the ventilation path 292 to the negative pressure source 145 or the open end 146 under the control of a control unit 150 of the bonding apparatus 100.

[0101] When the control valve 144 connects the ventilation path 292 to the negative pressure source 145, a negative pressure acts on the opening of the holding surface 291, so that the substrate 210 is adsorbed to the holding surface 291 of the substrate holder 290. When the control valve 144 connects the ventilation path 292 to the open end 146, the suction force of the holding surface 291 is eliminated, so that the substrate 210 is released from the suction of the holding surface 291 of the substrate holder 220.

[0102] The other vent path 294 has one end that opens to the bottom of the recess 293. The other end of the vent path 294 is coupled via a control valve 147 to a negative pressure source 148 and an open end 149 that are provided outside the substrate holder 290. The control valve 124 selectively connects the vent path 222 to the negative pressure source 125 or the open end 126 under the control of a control unit 150 of the bonding apparatus 100.

[0103] 28 is a perspective view of the protruding member 280. The protruding member 280 has a contact portion 281, a peripheral wall portion 282, and an air passage 284. The protruding member 280 is also an example of a forming portion that forms the protrusion 215 in a partial region of the substrate 210.

[0104] The contact portion 281 is disposed at the tip of a protrusion that protrudes upward in the figure at the center of the protrusion member 280. The peripheral wall portion 282 is disposed in an annular shape along the outer periphery of the protrusion member 280. As a result, a groove portion 283 is formed between the contact portion 281 and the peripheral wall portion 282.

[0105] The air passage 284 opens at one end into the groove portion 283 and penetrates to the underside of the protrusion member 280. When the protrusion member 280 is housed in the recess 293 of the main body portion 299, the air passage 284 communicates with the air passage 294 of the main body portion 299. Therefore, when the control valve 147 connects the air passage 294 to the negative pressure source 148, a negative pressure acts inside the groove portion 283 of the protrusion member 280, causing the substrate 210 to be adsorbed to the groove portion 283. In other words, the groove portion 283 is an example of an adsorption portion that sucks the substrate 210. When the control valve 147 connects the air passage 294 to the open end 149, the adsorption force in the groove portion 283 of the protrusion member 280 is released.

[0106] When the protruding member 280 is housed in the recess 293 of the main body 299, at least a portion of the abutting portion 281 and at least a portion of the peripheral wall 282 protrude from the holding surface 291. In the illustrated example, the height of the peripheral wall 282 is lower than that of the abutting portion 281.

[0107] 27 again, the height G of the peripheral wall portion 282 of the protruding member 280 is greater than the depth H of the recessed portion 293, and the upper end of the peripheral wall portion 282 in the figure protrudes from the holding surface 291. Furthermore, the height J of the abutting portion 281 is even greater than the peripheral wall portion 282 in the illustrated example, and the upper end of the abutting portion 281 in the figure protrudes further from the peripheral wall portion 282.

[0108] Figure 29 is a flow chart showing the procedure for bonding substrates 210, 230 using bonding apparatus 100 shown in Figure 5, substrate holder 260 shown in Figure 17, and substrate holder 290 shown in Figure 27. Of the procedures shown in Figure 29, the same operations as those shown in Figure 2 are denoted by the same reference numerals and the explanation will be simplified.

[0109] First, the substrates 210 and 230 are held by the substrate holders 290 and 260, respectively (step S101). Here, the substrate holder 290 adheres the substrate 210 to both the ventilation passage 292 of the main body 299 and the groove 283 of the protruding member 280 by suction.

[0110] As a result, the area of ​​the substrate 210 other than the central portion is adsorbed onto the holding surface 291 of the main body portion 299. Furthermore, a part of the central portion of the substrate 210 abuts against the abutment portion 281 of the protrusion member 280, thereby forming a protrusion 215 in the central portion. Furthermore, a part of the outer periphery of the protrusion 215 abuts against the upper end of the peripheral wall portion 282 of the protrusion member 280, thereby adsorbing the central portion of the substrate 210 to the groove portion 283.

[0111] Next, the substrates 210 and 230 held by the substrate holders 290 and 260 are carried into the bonding apparatus 100 (step S102), as shown in Fig. 30. In the illustrated example, the substrate holder 290 holding one of the substrates 210 is carried into the movable stage 141, and the substrate holder 260 holding the other substrate 230 is carried into the fixed stage 121.

[0112] After position measurement (step S103), substrate activation (step S104), and substrate alignment (step S105) are performed, the control unit 150 switches the control valve 144 to connect the ventilation path 292 of the holding surface 291 of the substrate holder 290 to the open end 146, as shown in Fig. 31. This releases the suction of the area of ​​the substrate 210 excluding the central portion thereof to the holding surface 291 (step S111).

[0113] When the holding by the holding surface 291 is released, the substrate 210 may be actively separated from the holding surface 291 by ejecting a fluid onto the surface of the holding surface 291 through the ventilation path 292. This facilitates the release of the substrate 210 and shortens the time required to proceed to the next step. Furthermore, by pushing the substrate 210 away from the holding surface 291 with the ejected fluid, deformation of the substrate 210 at the protrusion 215 can be alleviated.

[0114] 32 is a graph showing the change in the cross-sectional shape of protrusion 215 of substrate 210 held by substrate holder 290. As shown by curve P, when both holding surface 291 and protrusion member 280 are adsorbing substrate 210, the center of substrate 210 comes into close contact with abutment portion 281, thereby forming protrusion 215.

[0115] When the suction on the holding surface 291 of the substrate holder 290 is released and the outer periphery of the substrate 210 is further pushed up by the fluid ejected from the air passage 292, the outer periphery of the protrusion 215 is deformed as shown by the arrow X, and the curvature of the tip of the protrusion 215 becomes smaller than that of the curve P, as shown by the curve R in the figure, without changing the height of the protrusion 215.

[0116] Furthermore, when the ejection of fluid from ventilation path 292 is stopped, protrusion 215 of substrate 210, to which the upward force is no longer acting, has a curvature at the tip of protrusion 215 that is greater than that of curve R and smaller than that of curve P, as shown by arrow Y, without changing the height of protrusion 215, as shown by curve Q in the drawing. In the state of curve Q, the curvature is lower than that of curve P, in which there is no active ejection of fluid, and deformation of substrate 210 at protrusion 215 is alleviated.

[0117] Furthermore, when the holding by the holding surface 291 is released, vibrations may occur in the substrate 210 as it moves away from the holding surface 291. If the next step is performed while the vibrations remain, this may affect the alignment accuracy of the substrates 210 and 230. Therefore, after step S111, before performing the next step, it may be possible to wait until the amplitude of the vibration of the substrates becomes large enough that the substrates 210 and 230 do not come into contact with each other except at their centers, or until the vibration of the substrates changes the traveling speed of the bonding wave so that the amount of misalignment between the substrates 210 and 230 does not exceed an allowable value.

[0118] At the stage of step S111, the substrate holder 290 continues to adsorb the substrate 210 by the groove portion 283 of the protruding member 280. Therefore, the protrusion portion 215 is still formed on the substrate 210 by the abutment portion 281. In this state, as shown in Fig. 33, the control unit 150 causes the Z-direction driving unit 133 to raise the moving stage 141, and brings the protrusion portion 215 of the substrate 210 into contact with the other substrate 230 to form a joining starting point 209 (step S106).

[0119] Although the outer peripheral portion of substrate 210 is released from the holding by holding surface 291, the suction force of protruding member 280 acts in a direction that moves substrate 210 away from substrate 230. Therefore, even if joining starting points 209 are formed on substrates 210 and 230, the contact area is prevented from expanding.

[0120] Next, the control unit 150 controls the control valve 147 to connect the ventilation paths 294, 284 to the open end 149. As a result, as shown in Fig. 34, the suction of the substrate 210 by the protrusion member 280 is released (step S107), and a bonding wave advances on the substrates 210, 230 (step S108). At this time, the control unit 150 controls the position of the moving stage 141 so that the abutment portion 281 of the protrusion member 280 maintains the state in which the substrate 210 is pressed against the substrate 230, so that no misalignment occurs between the substrates 210, 230 while the bonding wave advances.

[0121] In step S106, when the substrate 210, whose outer periphery is not held, comes into contact with the substrate 230 to form the bonding starting points 209, vibrations may occur on the outer periphery of the substrate 210. If the next step is performed while the vibrations remain in the substrate 210, this may affect the alignment accuracy of the substrates 210 and 230. Therefore, as described above, the next step may be performed after the vibrations of the substrate become sufficiently small.

[0122] 2, the bonding wave reaches the outer periphery and the bonding is completed (step S109), and then the formed laminated substrate 201 is carried out from the bonding apparatus 100. In this way, the protruding member 280 may also have a suction function, so that the bonding process of the substrates 210 and 230 can be finely controlled.

[0123] Furthermore, in the above example, height J of contact portion 281 of protrusion member 280 is greater than height G of peripheral wall portion 282. However, height J of contact portion 281 may be the same as height G of peripheral wall portion 282. When height G is equal to height J of contact portion 281, the suction force on substrate 210 is large, and therefore protrusion member 280 can reliably hold substrate 210.

[0124] FIG. 35 is a table showing the correspondence between the substrate holders 220, 240, 260, 270, and 290 used to bond the substrates 210 and 230 and the bonding procedures shown in FIGS.

[0125] In the illustrated table, "holder without protruding members" refers to the flat substrate holder 240 shown in Fig. 4 and the like, and the substrate holder 260 having the curved holding surface 261 shown in Fig. 17. Also, in the illustrated table, "holder with protruding members" refers to the substrate holder 220 having the protruding members 250 shown in Fig. 3 and the like, and the substrate holder 290 having the protruding members 280 with the peripheral wall portion 282 shown in Fig. 27 and the like.

[0126] In addition, in the illustrated table, "procedure in FIG. 2" refers to a procedure in which the substrate holders 240, 260 release the substrate 230 (step S107) exclusively on the holding surfaces 241, 261. In the illustrated table, "procedure in FIG. 29" refers to a procedure in which the substrate holders 220, 280 release the substrate 210 at different stages, on the holding surfaces 241, 261 (step S111) and the protrusion member 280 (step S112).

[0127] Furthermore, in the illustrated table, "continue holding" means continuing to hold the substrate 230 until bonding is complete. Note that if the substrate holders 220, 240 on both the fixed stage 121 side and the movable stage 141 side do not release their hold on the substrates 210, 220, the substrates 210, 220 will not be bonded, and therefore there is no compatible bonding procedure. Also, if the substrate holder 290 having the protruding member 280 is not used on either side, there is no choice of procedure, and therefore compatibility is not listed in the illustrated table.

[0128] As shown in the figure, when using a substrate holder 290 equipped with protruding members 280 that themselves attract and hold the substrate 210 to suppress bonding, the procedure shown in Fig. 29 can be performed. Furthermore, even if the substrate 210 continues to be held by the substrate holder 290 having the protruding members 280 and the substrate 230 is released on the side of the substrate holder 240 that does not have the protruding members 280, the substrates 210 and 220 can be bonded. Furthermore, as described with reference to Fig. 20, by releasing the hold of both substrates 210 and 230 and allowing the bonding to proceed, misalignment due to changes in magnification during the bonding process can be suppressed.

[0129] However, even when a substrate holder 290 capable of suctioning the substrate 210 with the protrusion members 280 and suppressing the propagation of the bonding wave is used, if the substrate holder 290 is held on the fixed stage 121 side and the substrate 210 is held facing downward in the direction of gravity, it may not be possible to completely suppress substrate bonding simply by suctioning the vicinity of the center of the substrate with the protrusion members 280. Therefore, when the substrate holder 290 with the protrusion members 280 is used on the fixed stage 121 side, the procedure shown in FIG. 2 may be applied.

[0130] In the series of methods shown in Figure 35, if the substrates held by the substrate holder with protruding members are not released and the substrates held by the substrate holder without protruding members are released to bond the substrates, the released substrate may not deform to conform to the protruding portions of the fixed substrate. In such cases, there is a risk that bonding at the protruding portions will not be performed properly. Even in such cases, the entire substrates may be bonded, for example, using the method described below. One method is to use substrate holders with protruding members on both stages, butt the protruding members of the two substrate holders together, and then release the substrates from the two substrate holders. Another method is to make the protruding members of both substrate holders movable as described below, bring the protruding portions of the two substrates into contact with each other, and then apply pressure between the substrate holders to gradually expand the contact area between the protruding portions by reducing the protruding amounts of the two protruding members.

[0131] In the above example, the vent passages 222, 242, 262, 272, 274, 284, 294, 322, 331, 332, 352, 382, ​​292 of the substrate holders 220, 240, 260, 270, 290, etc. were connected to the open ends 129, 146, 149 to release the substrates 210, 220. However, the substrates 210, 220 may also be actively released by connecting the vent passages 222, 242, 262, 272, 274, 284, 294, 322, 331, 332, 352, 382, ​​292 to a pressure source that generates a positive pressure.

[0132] 2, in the procedure in which the substrates 210, 220 are held solely by the holding surfaces 221, 241 of the substrate holders 220, 240, the timing for applying positive pressure to the substrates 210, 220 is the point in time when at least one of the substrates 210, 220 is released (step S107) after the bonding starting points 209 are formed on the substrates 210, 220. This promotes the formation and propagation of bonding waves on the substrates 210, 220, and improves the throughput of substrate bonding.

[0133] 29, in the procedure in which the holding of the substrates 210, 220 is gradually released by the holding surfaces 221, 241 of the substrate holders 220, 240 and the protrusion members 280, the timing for applying positive pressure to the substrates 210, 220 may be the point in time when the holding by the holding surfaces is released (step S111), or the point in time when the holding by the protrusion members 280 is released (step S112). In particular, if positive pressure is applied at the point in time when the holding by the holding surfaces is released (step S111) before the two substrates 210, 220 come into contact with each other, it is possible to prevent the effects of shock, vibration, etc. that occurs on the substrates 210, 220 due to the application of positive pressure itself from affecting measurements such as alignment.

[0134] 36 and 37 are schematic cross-sectional views showing the structure and use of a substrate holder 296 that can be used in place of substrate holder 290. Elements common to substrate holder 290 are given the same reference numerals and redundant explanations will be omitted.

[0135] 36, the main body 298 of the substrate holder 296 is recessed toward the center and gradually becomes thicker toward the periphery, and is carried into the movable stage 141 at the bottom of the figure. The fixed stage 121 facing the movable stage 141 holds the substrate holder 260, which has a main body 269 that is thick in the center and becomes thinner toward the periphery, together with the substrate 230.

[0136] 37, when substrate holders 260 and 296 having the above-described shapes are used in combination, the substrates 230 and 210 held on holding surfaces 261 and 297 of substrate holders 260 and 296, respectively, have shapes that are approximately complementary to each other. In the example shown, substrate holder 260 is provided with protruding members 280, which form a protrusion 215 in the center of substrate 210. In this case, the curvature of the tip of protrusion 215 is greater than the curvature of holding surface 297 of substrate holder 296, i.e., the curvature of the region of substrate 210 other than the region where protrusion 215 is formed.

[0137] As a result, when the substrates 210 and 230 approach each other and a bonding starting point is formed, most of the substrates 210 and 230 face each other at a substantially constant distance. As a result, when a bonding wave progresses between the substrates 210 and 230, the amount of movement of the substrate 210, which is released from the substrate holder 296, toward the substrate 230 is reduced. This makes it possible to reduce the misalignment between the substrates 210 and 230 that occurs during the progression of the bonding wave.

[0138] Furthermore, when correcting misalignment between the substrates 210 and 230, the range of correction can be increased and the correction pitch can be reduced by correcting using both substrate holders 260 and 296 individually rather than correcting using the substrate holder 260 alone.

[0139] 38 is a partial cross-sectional view showing the structure of another substrate holder 401. The substrate holder 401 includes a main body portion 319 and a protruding member 301.

[0140] Main body 319 has recess 313 in part of flat holding surface 311. The bottom surface of recess 313 penetrates main body 319 in the thickness direction. Also, rib portions 312 that protrude inward are arranged on the inner surface of recess 313.

[0141] The protruding member 301 includes an abutting member 320, an intermediate member 330, and a nut 340. The abutting member 320 has an overall disk-like shape and has an air passage 322 that penetrates in the thickness direction. The abutting member 320 also has an abutting portion 321 that protrudes from the upper surface. As will be described later, when the protruding member 301 is fixed inside the recess 313, the abutting portion 321 protrudes from the holding surface 311. This allows the abutting portion 321 to form a protrusion 215 on the substrate 210 held on the holding surface 311. In other words, the protruding member 301 is an example of a forming portion that forms the protrusion 215 in a partial region of the substrate 210.

[0142] Furthermore, intermediate member 330 supports contact member 320 at its upper end, and a flange-like portion provided at the upper end in the drawing abuts against the upper surface of rib portion 312 of main body portion 319, thereby remaining inside recess 313. A screw thread 333 is arranged at the lower end of the outer periphery of intermediate member 330. Note that contact member 320 is fixed to intermediate member 330 by adhesive, double-sided tape, screwing, or the like.

[0143] Furthermore, intermediate member 330 has ventilation passage 331 formed horizontally on its upper surface and ventilation passage 332 passing through its center in the height direction. Ventilation passages 331 and 332 communicate with ventilation passage 322 of contact member 320 supported on the upper surface of intermediate member 330, and are connected to a negative pressure source (not shown). This allows substrate holder 401 to adsorb substrate 210 even inside recess 313.

[0144] The nut 340 has threads 343 on its inner surface that mesh with the threads 333 of the intermediate member 330. The nut 340 also has an outer diameter that is larger than the inner diameter of the rib portion 312 of the main body portion 319. As a result, by screwing the nut 340 into the lower end of the intermediate member 330, the rib portion 312 is sandwiched between the intermediate member 330 and the nut 340, and the protruding member 301 can be fixed to the main body portion 319. Furthermore, by loosening the nut 340, the protruding member 301 can be removed from the main body portion 319.

[0145] 39 is a cross-sectional view showing the structure of another protrusion member 302 that can be attached to the main body 319 of the substrate holder 401 instead of the protrusion member 301. The protrusion member 302 includes a contact member 350, an intermediate member 330, and a nut 340.

[0146] In protruding member 302, intermediate member 330 and nut 340 are the same as those in protruding member 301. In contrast, abutting member 320 has a disk-like shape overall, and has a structure in common with abutting member 320 of protruding member 301 in that it has air passage 352 penetrating in the thickness direction and abutting portion 351 protruding from the upper surface.

[0147] The contact member 350 further has a different shape from the contact member 320 in that it has a peripheral wall portion 353 provided around the contact portion 351. The peripheral wall portion 353 protrudes from the holding surface 311 when the protruding member 302 is fixed inside the recessed portion 313. However, the amount of protrusion is smaller than that of the contact portion 351.

[0148] As a result, when the substrate 210 is held by the substrate holder 401 equipped with the protruding member 302, the abutting portion 351 abuts against the substrate 210, forming a protruding portion 215 on the substrate 210, and the outer periphery of the protruding portion 215 can be sucked by depressurizing the space between the abutting portion 351 and the peripheral wall portion 353. In other words, the protruding member 302 is an example of a forming portion that forms the protruding portion 215 in a partial region of the substrate 210.

[0149] As described above, the substrate holder 401 can be used to bond substrates using different methods by replacing the protruding members 301 and 302. This improves the operating rate of the expensive main body 319 and the productivity of the laminated substrate 201. Furthermore, multiple protruding members with different heights of the contact portions may be prepared to adjust the protrusion amount of the contact portions. In this case, the protruding members may be replaced depending on the target bonding strength between the substrates 210 and 230, the degree of activation of the surfaces of the substrates 210 and 230, and the amount of correction for misalignment between the substrates 210 and 230. Furthermore, even without preparing multiple protruding members 301 and 302, the protrusion amount of the contact portions 321 and 351 can be adjusted by inserting shims of different thicknesses between the intermediate member 330 and the rib portion 312 or between the intermediate member 330 and the contact member 320.

[0150] 40 is a partial cross-sectional view showing the structure of yet another substrate holder 402. The substrate holder 402 comprises a main body 319 and a protruding member 303.

[0151] Main body 319 has recess 313 in part of flat holding surface 311. The bottom surface of recess 313 penetrates main body 319 in the thickness direction. Also, rib portions 314 that protrude inward are arranged on the inner surface of recess 313.

[0152] The protruding member 303 includes an abutting member 320, an intermediate member 330, and a ring member 360. Similar to the abutting member 320 of the protruding member 301, the abutting member 320 has an overall disk-like shape and includes an air passage 322 that penetrates in the thickness direction. The abutting member 320 also includes an abutting portion 321 that protrudes from the upper surface. When the protruding member 303 is fixed to the recess 313 of the main body portion 319, the abutting portion 321 protrudes from the holding surface 311. This allows the abutting portion 321 to form a protrusion 215 on the substrate 210 held on the holding surface 311. In other words, the protruding member 303 is an example of a forming portion that forms the protrusion 215 in a partial region of the substrate 210.

[0153] Intermediate member 330 supports contact member 320 at its upper end. Contact member 320 is fixed to intermediate member 330 by adhesive, double-sided tape, screwing, or the like. Furthermore, intermediate member 330 is provided at its upper end in the figure, and a flange-like portion that widens outward is brought into contact with the upper surface of rib portion 314 of main body portion 319, thereby preventing intermediate member 330 from falling downward from inside recess 313. Furthermore, intermediate member 330 shown in FIG. 40 has a shorter downward extending portion than intermediate member 330 in protrusion member 301 shown in FIG. 38. As a result, the lower end of intermediate member 330 is positioned inside recess 313 and extends to approximately the same height as the lower surface of rib portion 314.

[0154] Intermediate member 330 has air passage 331 formed horizontally on its upper surface and air passage 332 passing through its center in the height direction. Air passages 331 and 332 communicate with air passage 322 of contact member 320 supported on the upper surface of intermediate member 330, and are connected to a negative pressure source (not shown).

[0155] The ring member 360 has a cylindrical guide portion 361 that is inserted inside the intermediate member 330, and a flange portion 362 that expands radially from the lower end of the guide portion 361. Therefore, when fixing the protruding member 303 to the main body portion 319, the guide portion 361 of the ring member 360 is inserted from below into the intermediate member 330 that has been inserted into the recess 313 from the upper side in the figure, and the rib portion 314 of the main body portion 319 is sandwiched between the intermediate member 330 and the flange portions of the ring member 360. The intermediate member 330 and the ring member 360 can be fixed together using adhesive 370, a magnet, or the like.

[0156] As described above, the substrate holder 402 has a simple structure and requires fewer assembly steps. In the example shown in Fig. 40, the ring member 360 may be omitted, and the intermediate member 330 may be directly fixed to the rib portion 314 using an adhesive or the like.

[0157] 41 is a partial cross-sectional view showing the structure of yet another substrate holder 403. The substrate holder 403 comprises a main body portion 319 and a protruding member 304.

[0158] Main body 319 has recess 313 in part of flat holding surface 311. The bottom surface of recess 313 penetrates main body 319 in the thickness direction. Also, rib portion 315 that protrudes inward is arranged on the inner surface of recess 313.

[0159] Protrusion member 304 is formed from a single component. The upper part of protrusion member 304 is a disk having a diameter larger than the inner diameter of rib portion 315, and a protrusion having a contact portion 381 is disposed in the center of the upper surface in the drawing. In addition, an air passage 382 opens in the disk portion.

[0160] The lower part of the protruding member 304 is cylindrical with an outer diameter that allows it to be inserted inside the rib part 315. The lower end of the cylindrical part is provided with a tapered part 383 whose outer diameter decreases as it goes upward in the drawing.

[0161] The protrusion member 304 is fixed to the main body 319 by inserting its lower end portion into the inside of the rib portion 315 and then fitting an O-ring into the tapered portion 383. The O-ring 390 is urged upward by its own elasticity, narrowing the diameter of the tapered portion 383, preventing rattling between the protrusion member 304 and the main body 319. In addition, the protrusion amount of the abutment portion 381 can be adjusted by inserting a spacer between the disk portion at the upper end of the protrusion member 304 and the upper surface of the rib portion 315 of the main body 319. The protrusion member 304 is an example of a forming portion that forms the protrusion 215 in a partial region of the substrate 210.

[0162] Fig. 42 is a partial schematic cross-sectional view of another substrate holder 501. Note that substrate holder 501 is formed by combining a main body 319 common to other substrate holders 401 to 404 shown in Figs. 38 to 41 with protrusion members 405 having a different structure from those of substrate holders 401 to 404.

[0163] The protruding member 405 of the substrate holder 501 has an abutting member 420, an intermediate member 430, and a screw member 440. The abutting member 420 includes an abutting portion 421 and a base portion 422. The base portion 422 has a flat, disk-like shape. The abutting portion 421 is formed by protruding from the center of the base portion 422. The base portion 422 has a larger area than the abutting portion 421 and extends around the abutting portion 421.

[0164] The intermediate member 430 has a recessed portion 431, a circumferential groove 432, a screw thread 433, and an upper flange portion 434. The recessed portion 431 is formed on the upper surface of the intermediate member 430 and is large enough to accommodate the base portion 422 of the abutting member 420. When the abutting member 420 is accommodated in the recessed portion 431, the upper end of the abutting portion 421 protrudes upward in the figure beyond the upper surface of the intermediate member 430. The abutting member 420 accommodated in the recessed portion 431 of the intermediate member 430 is fixed to the intermediate member 430 by an adhesive or the like.

[0165] The intermediate member 430 also has a circumferential groove 432 that runs around the periphery of its side surface. An O-ring 490 is housed in the circumferential groove 432. The intermediate member 430 also has a screw hole that passes through the center in the height direction and has a screw thread 433 on the inner surface. The screw thread 433 screws into a screw thread 443 of a screw member 440, which will be described next.

[0166] The upper end side of the intermediate member 430 in the figure forms an upper flange portion 434 having an outer diameter larger than the inner diameter of the rib portion 312 formed on the inner surface of the recessed portion 313 of the main body portion 319. In contrast, the lower end side of the intermediate member 430 in the figure has an outer diameter smaller than the inner diameter of the rib portion 312. Therefore, when the intermediate member 430 is attached to the main body portion 319 from the holding surface 311 side, the lower end of the intermediate member 430 is inserted into the inside of the rib portion 312 of the main body portion 319.

[0167] The screw member 440 has a lower flange portion 442 and a screw thread 443. As already described, the screw thread 443 has a size and shape that allows it to threadably engage with the screw thread of the intermediate member 430. The lower flange portion 442 has an outer diameter that is larger than the inner diameter of the rib portion 312 of the main body portion 319. Therefore, when the screw member 440 is attached to the main body portion 319 from the side opposite the holding surface 311 and the screw threads 433, 443 of the intermediate member 430 and the screw member 440 are threadedly engaged, the rib portion 312 of the main body portion 319 is sandwiched between the upper flange portion 434 of the intermediate member 430 and the lower flange portion 442 of the screw member 440. This prevents the protrusion member 405 from coming off the main body portion 319.

[0168] Here, the distance between the upper flange portion 434 and the lower flange portion 442 is greater than the thickness of the rib portion 312. Therefore, the protrusion member 405 is attached to the main body portion 319 so as to be movable up and down. In the substrate holder 501, a disc spring 450 is disposed between the upper flange portion 434 and the rib portion 312. The disc spring 450 biases the upper flange portion 434 in a direction away from the rib portion 312. This maintains the protrusion member 405 in a state in which the abutment portion 421 protrudes to the greatest extent within its movable range.

[0169] When the substrates 210 and 230 are bonded in the bonding apparatus 100 using the substrate holder 501 equipped with the protruding member 405 described above, when the substrate 210 is initially held by the substrate holder 501, the abutting portion 421 protruding from the holding surface 311 forms a protruding portion 215 on the substrate 210. That is, the protruding member 405 is an example of a forming portion that forms the protruding portion 215 in a partial region of the substrate 210. When forming a bonding starting point, the moving stage 141 is further raised while the protruding portion 215 of the substrate 210 is in contact with the substrate 230 to be bonded, thereby reducing the protruding amount of the protruding member 405 against the biasing force of the disc spring 450. As the protruding amount of the protruding member 405 decreases, the size of the contact area between the substrates 210 and 230 increases. This allows the size of the contact area between the substrates 210 and 230 to be adjusted when forming the starting point.

[0170] In the substrate holder 501, for example, the protrusion amount of the abutting portion 421 can be adjusted by replacing the adjusting shim 461 sandwiched between the lower surface of the intermediate member 430 and the lower flange portion 442 of the screw member 440 with one of a different thickness. Also, in the substrate holder 501, the pressure with which the abutting portion 421 presses the substrate 210 can be adjusted by replacing the adjusting shim 462 sandwiched between the disc spring 450 and the rib portion 312 as shown in the figure with one of a different thickness. The adjusting shim 462 for the disc spring 450 may be sandwiched between the disc spring 450 and the upper flange portion 434 of the intermediate member 430.

[0171] In each of the above-described embodiments, when adjusting the amount of protrusion of the protruding member from the holding surface of the substrate holder, a plurality of protruding members with contact portions of different heights may be prepared, and the protruding member may be selected and used depending on the size of the welding starting point to be formed, the speed of the welding wave, the amount of misalignment between the substrates that occurs during welding, etc. Furthermore, if the amount of misalignment between the substrates that occurs during welding changes depending on the change in the amount of protrusion of the protruding member, the amount of convexity of the holding surface 261 of the substrate holder 260 as shown in Figure 17, i.e., the amount of correction for the substrates held on the holding surface 261, may be adjusted depending on the amount of protrusion of the protruding member.

[0172] 43 is a schematic cross-sectional view of substrate holder 502. Substrate holder 502 has the same structure as substrate holder 501, except that disc spring 450 and one of adjusting shims 462 are omitted.

[0173] In the substrate holder 502, the protruding member 405 is also attached displaceably so that the amount of protrusion relative to the main body 319 can be changed. Therefore, for example, by using pressurized fluid to urge the protruding member 405 from below to above in the figure, as indicated by the outline arrow Z in the figure, the same function as the substrate holder 501 equipped with the disc spring 450 can be achieved. Furthermore, by adjusting the pressure of the pressurized fluid externally, the pressure applied by the abutting portion 421 can be adjusted in the process of joining the substrates 210 and 230.

[0174] 44 is a schematic cross-sectional view of another substrate holder 503. Substrate holder 503 has a structure in which main body 319 itself is shaped and abutment portion 321 is provided on holding surface 311. In this way, even when substrate holder 503 having abutment portion formed thereon is used, it is possible to control the joining starting point when joining substrates 210, 230, without providing separate protrusion member 405 on main body 319. The abutment portion formed on substrate holder 503 in this way is an example of a protrusion that forms the protrusion by abutting against a partial region of substrates 210, 230 held on the holding surface.

[0175] 45 is a schematic cross-sectional view of yet another substrate holder 504. The substrate holder 504 has a structure in which the main body 319 itself is shaped to provide a contact portion 351 and a peripheral wall portion 353 on the holding surface 311. In the substrate holder 504 having such a main body 319, by providing an air passage that opens between the contact portion 351 and the peripheral wall portion 353, it is possible to form a substrate holder 504 with a simple structure that has the same function as the substrate holder 290 shown in FIG. 27. In this case, the contact portion 351 constitutes a forming portion that forms the protrusion 215 in a partial region of the substrate 210.

[0176] The various structures for forming contact portions on the substrate holders 401, 402, 403, 501, 502, 503, and 504 described above may be provided on the stage that holds the substrate in a bonding apparatus that bonds substrates without using a substrate holder.

[0177] Furthermore, in this embodiment, an example was shown in which a protrusion member for forming the protrusion 215 was provided on the substrate holder or stage. However, instead, a protrusion member that penetrates the substrate holder or stage and is arranged so as to be movable toward the substrate held by the substrate holder or stage may be used. In this case, an actuator that moves the protrusion member may be used to control the amount of protrusion from the holding surface of the substrate holder or stage. Furthermore, in this case, by measuring the position of the alignment mark after forming the protrusion on the substrate with the protrusion member, it is possible to suppress misalignment between the substrates after position measurement. The protrusion member and the actuator constitute a forming unit that forms the protrusion 215 in a partial region of the substrate 210.

[0178] Furthermore, in this embodiment, the protruding portion 215 of the substrate 210 is elongated or contracted by the amount of protrusion from its original state before being held by the substrate holder. Therefore, the protruding portion 215 may be joined to the central portion of the substrate 230 in an elongated or contracted state. In this case, the amount of protrusion and shape of the holding surface 241 of the substrate holder 240 may be set so that the surface at the central portion of the substrate 230 is deformed in advance by an amount corresponding to the amount of protrusion of the protruding member 250 from the holding surface 221 of the substrate holder 220 or the deformation amount of the protruding portion 215.

[0179] Alternatively, a deformation mechanism having an actuator that deforms the central portion of the substrate holder 240 may be provided below the substrate holder 240, and the substrate 230 may be deformed in advance by deforming the substrate holder 240 by driving the actuator with a drive amount corresponding to the amount of protrusion of the protrusion member 250 from the holding surface 221 of the substrate holder 220 or the amount of deformation of the protrusion portion 215.

[0180] Alternatively, when the substrate 210 held by a substrate holder provided with the protruding member 250 is released from the substrate holder to be bonded to another substrate 230 held by another substrate holder, the suction force at the center of the substrate 230 is released or weakened as shown in FIG. 20 while the other substrate holder holds an area other than the center of the substrate 230. This allows the substrate 230 to be peeled off from the other substrate holder by the suction force between the substrates 210 and 230 when the protruding portion 215 of the substrate 210 comes into contact with the other substrate 230 during formation of the starting points. This allows the same deformation as that occurring in the protruding portion 215 of the substrate 210 to be generated in the center of the substrate 230, thereby reducing the difference between the amount of deformation of the protruding portion 215 of the substrate 210 and the amount of deformation of the center of the substrate 230 and suppressing misalignment due to the difference in the amount of deformation.

[0181] In this case, the chucking area of ​​the other substrate holder may be divided into multiple areas, and the chucking force may be controlled individually for each area. If the chucking method is a vacuum chuck, the pressure acting on the substrate 230 is controlled for each area, and if the chucking method is an electrostatic chuck, the voltage applied to each area is controlled individually.

[0182] After the formation of the starting point, the substrate 210 is released from the substrate holder to form a bonding wave. At this time, as the bonding with the substrate 210 progresses from the starting point, the center of the substrate 230 is returned toward the other substrate holder due to the weight of the substrate 210, and the deformations generated in the protrusion 215 of the substrate 210 and the center of the substrate 230 are simultaneously returned to their pre-deformation states. This makes it possible to prevent misalignment between the substrates 210 and 230 due to differences in the amount of deformation while the bonding wave is progressing.

[0183] Furthermore, when the substrate 210 is released from the substrate holder 220, the elongation deformation that occurred in the protrusion 215 may be released, causing the protrusion 215 to return to the state it was in before the protrusion 215 was formed. In this case, the planar position of the surface of the substrate 210 at the protrusion 215 may deviate from the position at which the alignment mark 213 was detected. In this case, as described above, the amount of this deviation is measured or predicted in advance, and the surface at the center of the substrate 230 is deformed in advance by an amount of deformation that can correct this deviation. Alternatively, the position of the alignment mark 213 or the position of the moving stage 141 may be measured or controlled in consideration of the amount of recovery or deviation due to this release.

[0184] Furthermore, although the present embodiment illustrates an example in which the contact portions 251, 281, 321, 351, 381, and 421 are cylindrical, it is preferable to chamfer the corners formed by the contact surfaces and the peripheral surfaces to prevent scratches or damage to the contacting substrate 210. Furthermore, instead of cylindrical contact portions, contact portions having shapes other than cylindrical, such as hemispherical, conical, and truncated conical shapes, may be used. When a hemispherical contact portion is used, the contact portion may have a contact surface curved with a curvature equal to the curvature required for the tip of the protrusion 215 of the substrate 210. The required curvature corresponds to the area and shape of the contact region when the protrusion 215 and the substrate 230 can come into contact with each other without generating or trapping air bubbles between the tip of the protrusion 215 and the other substrate 230.

[0185] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0186] It should be noted that the execution order of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order. [Explanation of symbols]

[0187] 100 Bonding device, 110 Frame, 111 Bottom plate, 113 Top plate, 121 Fixed stage, 122 Upper microscope, 123 Upper activation device, 124, 127, 144, 147 Control valve, 125, 128, 145, 148 Negative pressure source, 126, 129, 146, 149 Open end, 131 X-direction drive unit, 132 Y-direction drive unit, 133 Z-direction drive unit, 141 Moving stage, 142 Lower microscope, 143 Lower activation device, 150 Control unit, 201 Laminated substrate, 209 Bonding starting point, 210, 230 Substrate, 211, 231 Scribe line, 213, 233 Alignment mark, 214, 234 Circuit area, 215 Protrusions, 220, 240, 260, 270, 290, 296, 401, 402, 403, 501, 502, 503, 504 Substrate holders, 221, 241, 261, 271, 291, 297, 311 Holding surfaces, 222, 242, 262, 272, 274, 284, 294, 322, 331, 332, 352, 382, ​​292 Ventilation channels, 223, 273, 293, 313 Recesses, 229, 249, 269, 279, 298, 299, 319 Main body, 250, 280, 301, 302, 303, 304, 405 Projecting member, 251, 281, 321, 351, 381, 421 Abutment portion, 282, 353 Circumferential wall portion, 283 Groove portion, 312, 314, 315 Rib portion, 320, 350, 420 Abutment member, 330, 430 Intermediate member, 333, 343, 433, 443 Thread, 340 Nut, 360 Ring member, 361 Guide portion, 362 Flange portion, 370 Adhesive, 383 Tapered portion, 390, 490 O-ring, 422 Base portion, 431 Depression portion, 432 Circumferential groove, 434 Upper flange portion, 440 Screw member, 442 Lower flange portion, 450 Belleville spring, 461, 462 Adjusting shim

Claims

1. A forming step of forming a protrusion having a larger curvature in a partial region of a first substrate than in other regions of the first substrate; measuring positions of a plurality of alignment marks provided in the other region of the first substrate in a state in which the protrusion is formed on the first substrate; an alignment step of aligning the first substrate and the second substrate based on the measured positions of the plurality of alignment indicators; a contacting step of contacting at least a portion of the protrusion of the first substrate with a portion of a surface of the second substrate after aligning the first substrate with the second substrate; a bonding step of contacting at least a part of the protrusion of the first substrate with a part of the surface of the second substrate, and then expanding a contact area of ​​the first substrate with respect to the second substrate to bond the first substrate and the second substrate together; A bonding method comprising:

2. The bonding method according to claim 1 , wherein the other region of the first substrate is flat or curved with a curvature smaller than that of the protrusion.

3. 3. The bonding method according to claim 1, wherein the measuring step measures the positions of a plurality of alignment marks, which are the plurality of alignment indicators provided in the other region of the first substrate, while the protrusion is formed on the first substrate.

4. holding the first substrate on a first holding surface and holding the second substrate on a second holding surface; The bonding method according to claim 1 , wherein the bonding step includes a control step of controlling the suction force of the first substrate by the first holding surface while suctioning the second substrate with the second holding surface.

5. 5. The bonding method according to claim 4, wherein the control step releases the suction force of the first substrate at least in an area adjacent to the protrusion while continuing to suction the first substrate at the protrusion before the protrusion of the first substrate comes into contact with a portion of the surface of the second substrate.

6. bending the second substrate; The bonding method according to claim 1 , wherein the bonding step includes bringing the protruding portion of the first substrate into contact with a part of a curved surface of the second substrate.

7. 7. The bonding method according to claim 1, wherein the bonding step starts expanding the contact area after the protrusion of the first substrate and a portion of the surface of the second substrate come into contact and a bonding force large enough to prevent misalignment between the protrusion and the second substrate is secured.

8. 8. The bonding method according to claim 1, wherein the bonding step starts expanding the contact area after the protrusion of the first substrate and a portion of the surface of the second substrate come into contact and vibration of at least one of the first substrate and the second substrate converges.

9. A first holding portion that adsorbs and holds a first substrate; a forming portion that forms a protrusion having a larger curvature in a partial region of the first substrate than in other regions of the first substrate; a measuring unit that measures positions of a plurality of alignment marks provided in the other region of the first substrate in a state in which the protrusion is formed on the first substrate; an alignment unit that aligns the first substrate and the second substrate based on the measured positions of the plurality of alignment indicators; a bonding unit that bonds the first substrate and the second substrate together by bringing at least a part of the protrusion of the first substrate into contact with a part of the surface of the second substrate after aligning the first substrate and the second substrate, and controlling the suction force of the first holding unit to expand a contact area of ​​the first substrate with the second substrate; and A joining device comprising:

10. The bonding device according to claim 9 , wherein the other area of ​​the first substrate is flat or curved with a curvature smaller than that of the protrusion.

11. The bonding apparatus according to claim 9 or 10, wherein the measurement unit measures the positions of a plurality of alignment marks, which are the plurality of alignment indicators, provided in the other region of the first substrate when the protrusion is formed on the first substrate.

12. The joining device according to claim 9 , wherein the forming portion is provided on the first holding portion.

13. a second holding unit that holds the second substrate by suction, The bonding device according to claim 9 , wherein the bonding unit maintains the suction force of the second holding unit on the second substrate while the first holding unit releases the suction force of the first substrate.

14. a second holding part that holds the second substrate; The joining device according to any one of claims 9 to 12, wherein the first holding portion is disposed above the second holding portion, and a holding surface of the first holding portion faces downward.

15. 15. The bonding device according to claim 9, wherein the bonding portion starts expanding the contact area after contacting the protrusion of the first substrate with a portion of the surface of the second substrate and after a bonding force large enough to prevent misalignment between the protrusion and the second substrate is secured.

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