Bonding device, bonding system, and bonding method

Abstract

The invention provides a bonding apparatus, a bonding system, and a bonding method. A bonding device for bonding a first substrate and a second substrate comprises: a first holding unit for holding the first substrate; a second holding unit that holds the second substrate, the second holding unit being disposed so as to face the first holding unit; a first displacement meter that measures the thickness of the first substrate; a second displacement meter that measures the thickness of the second substrate; and a first moving mechanism that moves the first displacement meter and the second displacement meter in a first direction in a planar region between the first holding part and the second holding part.

Description

[0001] This application is a divisional application of an application filed on April 27, 2020, with application number 202080032907.X (PCT / JP2020 / 018011), and invention name “Joining device, joining system, and joining method”. Technical Field

[0002] The present disclosure relates to a joining device, a joining system, and a joining method. Background Art

[0003] Patent Document 1 discloses a bonding device for bonding substrates. The bonding device includes a first holding portion for holding a first substrate, a second holding portion for holding a second substrate, a chamber for accommodating the first and second holding portions, and an imaging unit disposed outside the chamber. The imaging unit captures alignment marks formed on the first and second substrates via through-holes formed in the chamber, the first holding portion, and the second holding portion, respectively.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-134446 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] The technology according to the present disclosure improves the bonding accuracy when bonding substrates to each other.

[0009] Solutions for solving problems

[0010] One embodiment of the present disclosure is a joining device for joining a first substrate to a second substrate, the joining device comprising: a first holding portion that holds the first substrate; a second holding portion that holds the second substrate, the second holding portion being arranged opposite to the first holding portion; two camera units, the two camera units having a first camera unit and a second camera unit, the first camera unit photographing a first alignment mark formed on the joining surface of the first substrate, and the second camera unit photographing a second alignment mark formed on the joining surface of the second substrate; a first moving mechanism that moves the two camera units along a first direction within a planar area between the first holding portion and the second holding portion; a second moving mechanism that moves the first camera unit of the two camera units along a second direction orthogonal to the first direction; and a third moving mechanism that moves the second camera unit of the two camera units along the second direction.

[0011] Another embodiment of the present disclosure is a joining device for joining a first substrate to a second substrate, the joining device comprising: a first holding portion that holds the first substrate; a second holding portion that holds the second substrate, the second holding portion being arranged opposite to the first holding portion; a first displacement gauge that measures the thickness of the first substrate; a second displacement gauge that measures the thickness of the second substrate; and a first moving mechanism that moves the first displacement gauge and the second displacement gauge along a first direction within a planar area between the first holding portion and the second holding portion.

[0012] Another embodiment of the present disclosure is a joining system for joining a first substrate and a second substrate, the joining system comprising: a processing station equipped with a joining device for joining the first substrate and the second substrate; and a loading and unloading station for loading and unloading the first substrate, the second substrate, or a superimposed substrate formed by joining the first substrate and the second substrate relative to the processing station, wherein the joining device comprises: a first holding portion for holding the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged opposite to the first holding portion; a first displacement gauge for measuring the thickness of the first substrate; a second displacement gauge for measuring the thickness of the second substrate; and a first moving mechanism for moving the first displacement gauge and the second displacement gauge along a first direction within a planar area between the first holding portion and the second holding portion.

[0013] Another embodiment of the present disclosure is a bonding method for bonding a first substrate to a second substrate using a bonding device, the bonding device comprising: a first holding portion that holds the first substrate; a second holding portion that holds the second substrate, the second holding portion being arranged opposite to the first holding portion; a first displacement gauge that measures the thickness of the first substrate; a second displacement gauge that measures the thickness of the second substrate; and a first moving mechanism that moves the first displacement gauge and the second displacement gauge along a first direction within a planar area between the first holding portion and the second holding portion, the bonding method comprising the following steps: step (a) holding the first substrate by the first holding portion; step (b) holding the second substrate by the second holding portion; and step (c) measuring the thickness of the first substrate and the thickness of the second substrate while moving the first displacement gauge and the second displacement gauge in the first direction by the first moving mechanism.

[0014] Effects of the Invention

[0015] According to the present disclosure, it is possible to improve the bonding accuracy when indirectly bonding substrates to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a plan view schematically showing the structure of the joining system according to the present embodiment.

[0017] Figure 2 It is a side view schematically showing the internal structure of the joining system according to the present embodiment.

[0018] Figure 3 It is a side view schematically showing the structure of the superimposed substrates.

[0019] Figure 4 It is a plan view schematically showing the structure of the first substrate.

[0020] Figure 5 It is a side view schematically showing the structure of the bonding device.

[0021] Figure 6 It is a side view schematically showing the structure of the bonding device.

[0022] Figure 7 It is a plan view schematically showing the structure of the bonding apparatus.

[0023] Figure 8 It is a cross-sectional view of the first holding portion and its surrounding structure.

[0024] Figure 9 This is a plan view of the first holding portion and its surroundings as viewed from below.

[0025] Figure 10 This is a plan view of the first holding portion and its surroundings as viewed from above.

[0026] Figure 11 It is a cross-sectional view of the second holding portion and its surrounding structure.

[0027] Figure 12 It is a cross-sectional view of the second holding portion and its surrounding structure.

[0028] Figure 13 This is a plan view of the second holding portion and its surroundings as viewed from above.

[0029] Figure 14 It is a plan view schematically showing the structure of the first imaging unit.

[0030] Figure 15 It is a side view schematically showing the structure of the first imaging unit.

[0031] Figure 16 It is an explanatory diagram schematically showing the internal structure of the first imaging unit.

[0032] Figure 17 This is an explanatory diagram schematically showing the internal structure of a conventional imaging unit.

[0033] Figure 18 It is a side view schematically showing the structure of the reference mark portion.

[0034] Figure 19 This is a flowchart showing the main steps of the joining process.

[0035] Figure 20 It is an explanatory diagram showing steps A3 and A6 of the joining process.

[0036] Figure 21 It is an explanatory diagram showing steps A7 and A8 of the joining process.

[0037] Figure 22 It is an explanatory diagram showing step A9 of the joining process.

[0038] Figure 23 It is an explanatory diagram showing steps A9 and A10 of the joining process.

[0039] Figure 24 It is an explanatory diagram showing step A10 of the joining process.

[0040] Figure 25 It is an explanatory diagram showing step A11 of the joining process.

[0041] Figure 26 It is an explanatory diagram showing step A12 of the joining process.

[0042] Figure 27 It is an explanatory diagram showing step A13 of the joining process.

[0043] Figure 28 It is an explanatory diagram showing step A14 of the joining process.

[0044] Figure 29 It is an explanatory diagram showing the load state when the first substrate and the second substrate are pressed.

[0045] Figure 30 It is an explanatory diagram showing step A15 of the joining process.

[0046] Figure 31 It is an explanatory diagram showing step A15 of the joining process. DETAILED DESCRIPTION

[0047] In three-dimensional integration technology, which stacks semiconductor devices three-dimensionally, two semiconductor substrates (hereinafter referred to as "substrates") are bonded together. Specifically, the substrates are bonded together using, for example, van der Waals forces and hydrogen bonds (intermolecular forces). Furthermore, to properly manufacture semiconductor devices, it is important to properly align the upper first substrate with the lower second substrate during the bonding and stacking of the substrates.

[0048] Conventionally, in a bonding apparatus such as that disclosed in Patent Document 1, an imaging unit located outside a chamber captures images of alignment marks on a first substrate and a second substrate housed within the chamber. Based on the detection results of the captured alignment marks, the horizontal position and orientation of the first holding unit are adjusted to align the first and second substrates.

[0049] However, in the bonding apparatus of Patent Document 1, the imaging unit is fixed in the horizontal direction, so sometimes it is not possible to properly capture the alignment marks of the first and second substrates. In this case, proper alignment cannot be performed, and there is room for further improvement in terms of improving bonding accuracy.

[0050] The technology disclosed herein improves joining accuracy. The following describes a joining device, a joining system including the joining device, and a joining method according to this embodiment with reference to the accompanying drawings. Furthermore, in this specification and the accompanying drawings, elements having substantially the same functional structure are labeled with the same reference numerals to omit repeated descriptions.

[0051] <Structure of Joining System 1>

[0052] First, the configuration of the joining system according to this embodiment will be described. Figure 1 It is a plan view schematically showing the structure of the joining system 1 . Figure 2 It is a side view schematically showing the internal structure of the bonding system 1. In order to clarify the positional relationship, the X-axis direction, Y-axis direction, and Z-axis direction orthogonal to each other are defined below, and the positive Z-axis direction is defined as the vertical upward direction.

[0053] In the joint system 1, as Figure 3 As shown in FIG. 1 , the first substrate W1 and the second substrate W2 are bonded to form a superimposed substrate T. Hereinafter, the surface of the first substrate W1 that is bonded to the second substrate W2 is referred to as the "bonding surface W1a," and the surface opposite to the bonding surface W1a is referred to as the "non-bonding surface W1b." Furthermore, the surface of the second substrate W2 that is bonded to the first substrate W1 is referred to as the "bonding surface W2a," and the surface opposite to the bonding surface W2a is referred to as the "non-bonding surface W2b." Both the first substrate W1 and the second substrate W2 are semiconductor substrates, such as silicon substrates.

[0054] like Figure 4As shown, two first alignment marks M11 and M12 are formed on the bonding surface W1a of the first substrate W1. The first alignment marks M11 and M12 are respectively formed, for example, on the Y-axis passing through the center of the first substrate W1. In addition, the first alignment marks M11 and M12 each have a cross shape. Similarly, two second alignment marks M21 and M22 having a cross shape are also formed on the bonding surface W2a of the second substrate W2, for example, on the Y-axis passing through the center of the second substrate W2. In addition, the shapes of the alignment marks M11, M12, M21, and M22 are not limited to a cross shape, and any shape can be adopted.

[0055] like Figure 1 As shown, the joining system 1 has a structure obtained by connecting a load-in and load-out station 2 and a processing station 3 as a whole. The load-in and load-out station 2, for example, carries out the loading and unloading of boxes Cw1, Cw2, and Ct that can respectively accommodate multiple first substrates W1, second substrates W2, and overlapping substrates T between the outside, and the processing station 3 has various processing devices for performing desired processing on the substrates W1, W2, and overlapping substrates T.

[0056] A cassette placement table 10 is provided at the loading / unloading station 2. A plurality of, for example, four, cassette placement plates 11 are provided at the cassette placement table 10. The cassette placement plates 11 are arranged so as to extend in the horizontal X direction ( Figure 1 In the vertical direction (in the vertical direction) of the bonding system 1, the boxes Cw1, Cw2, Ct can be placed on these box loading plates 11 when the boxes Cw1, Cw2, Ct are loaded and unloaded relative to the outside of the bonding system 1. In this way, the loading and unloading station 2 is configured to be able to hold a plurality of first substrates W1, a plurality of second substrates W2, and a plurality of overlapping substrates T. In addition, the number of box loading plates 11 is not limited to the present embodiment and can be set arbitrarily. In addition, in addition to the boxes Cw1, Cw2, Ct, the box loading plates 11 can also be used to load boxes for recovering, for example, defective substrates.

[0057] A substrate transfer area 20 is provided in the loading / unloading station 2, adjacent to the cassette mounting table 10, on the positive X-axis side of the cassette mounting table 10. A substrate transfer device 22 is provided in the substrate transfer area 20, which is movable along a transfer path 21 extending along the Y-axis. The substrate transfer device 22 is also movable in the vertical direction and about a vertical axis (θ direction), and is capable of transferring a first substrate W1, a second substrate W2, and an overlapped substrate T between the cassettes Cw1, Cw2, and Ct on each cassette mounting plate 11 and the conveyor devices 60 and 61 of the third processing block G3 of the processing station 3, described later.

[0058] The processing station 3 is provided with a plurality of, for example, three, processing blocks G1, G2, and G3 equipped with various devices. Figure 1A first processing block G1 is provided on the back side of the processing station 3 ( Figure 1 The second processing block G2 is provided on the positive Y-axis side of the processing station 3. Figure 1 A third processing block G3 is provided on the negative X-axis side.

[0059] A bonding apparatus 30 for bonding the substrates W1 and W2 is disposed in the first processing block G1. The structure of the bonding apparatus 30 will be described later.

[0060] like Figure 2 As shown, the second processing block G2 has a two-story structure. In the lower story of the second processing block G2, the reforming device 40, the transfer chamber 41, and the load lock chamber 42 are arranged in the order shown in the horizontal X-axis direction from the loading / unloading station 2 side.

[0061] The modifying device 40 modifies the bonding surfaces W1a and W2a of the substrates W1 and W2. In the modifying device 40, oxygen or nitrogen gas, serving as a processing gas, is excited into plasma, for example, under a reduced pressure atmosphere, thereby ionizing the gas. These oxygen or nitrogen ions are irradiated onto the bonding surfaces W1a and W2a, thereby performing plasma treatment and modifying the bonding surfaces W1a and W2a.

[0062] The load lock chamber 42 is located adjacent to the substrate transfer area 70 (described later) via a gate valve (not shown) on the positive Y-axis side of the substrate transfer area 70. The load lock chamber 42 is configured to switch its internal space between atmospheric pressure and a vacuum state. Furthermore, a transfer portion (not shown) is provided within the load lock chamber 42 for transferring the first substrate W1 and the second substrate W2.

[0063] The transfer chamber 41 is located adjacent to the load lock chamber 42 on the negative side of the Y axis with a gate valve (not shown) interposed therebetween. A substrate transfer device (not shown) for transferring the first substrate W1 and the second substrate W2 is located in the transfer chamber 41. The substrate transfer device can transfer the first substrate W1 and the second substrate W2 between the load lock chamber 42 and the modifying device 40.

[0064] In the upper layer of the second processing block G2, the hydrophilization devices 50 and 51 are arranged horizontally along the X-axis, starting from the loading / unloading station 2, in the order described. The hydrophilization devices 50 and 51 hydrophilize and clean the bonding surfaces W1a and W2a of the substrates W1 and W2, for example, using pure water. In the hydrophilization device 50, pure water is supplied to the substrates W1 and W2 while rotating the substrates W1 and W2, which are held by a rotary chuck (not shown). The supplied pure water diffuses over the bonding surfaces W1a and W2a of the substrates W1 and W2, thereby hydrophilizing the bonding surfaces W1a and W2a.

[0065] In the third processing block G3 , the conveying devices 60 and 61 for the first substrate W1 , the second substrate W2 , and the superimposed substrate T are arranged in two stages in order from the bottom.

[0066] like Figure 1 As shown in FIG. 1 , a substrate transfer area 70 is formed in an area surrounded by the first to third processing blocks G1 to G3 . In the substrate transfer area 70 , for example, a substrate transfer device 71 is disposed.

[0067] The substrate transport device 71 includes a transport arm that is movable, for example, in the vertical direction, the horizontal direction (X-axis direction, Y-axis direction), and about the vertical axis. The substrate transport device 71 moves within the substrate transport area 70 and can transport the first substrate W1, the second substrate W2, and the superimposed substrate T to desired devices within the surrounding first processing block G1, the second processing block G2, and the third processing block G3.

[0068] In the above-described bonding system 1, a control device 80 is provided as a control unit. The control device 80 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program for controlling substrate processing in the bonding system 1. In addition, the program storage unit also stores a program for controlling the operation of the drive system of the various processing devices, conveying devices, etc. described above to implement the substrate processing described later in the bonding system 1. In addition, the above-mentioned program can be recorded in a computer-readable storage medium H and installed from the storage medium H into the control device 80.

[0069] <Structure of the bonding device 30>

[0070] Next, the structure of the above-mentioned bonding apparatus 30 will be described. Figure 5 and Figure 6 It is a side view schematically showing the structure of the bonding device 30 . Figure 7 It is a plan view schematically showing the structure of the bonding apparatus 30 .

[0071] The bonding apparatus 30 has a structure in which various components are mounted on a base 100. Specifically, the bonding apparatus 30 has a processing container 110, a first holding portion 120, and a second holding portion 130. In addition, the bonding apparatus 30 has a chamber lifting mechanism 140 and a decompression portion 150 around the processing container 110. In addition, the bonding apparatus 30 has a support portion 160, a horizontal position adjustment portion 170, a vertical position adjustment portion 180, and a pressurizing portion 190 around the first holding portion 120. In addition, the bonding apparatus 30 has fixed imaging portions 200 and 201 around the second holding portion 130. Furthermore, the bonding apparatus 30 has imaging units 210 and 211 that move between the inside and outside of the processing container 110. Each structure will be described below.

[0072] (Structure of the Processing Container 110 and Its Periphery)

[0073] First, the processing container 110 and its surrounding structures will be described.

[0074] The processing container 110 is a container with a hermetically sealed interior, and is used to accommodate the first holding portion 120 and the second holding portion 130. The processing container 110 is divided into two parts, and the processing container 110 has a first chamber 111 on the first holding portion 120 side (upper side) and a second chamber 112 on the second holding portion 130 side (lower side). A seal 113 is provided on the joint surface between the second chamber 112 and the first chamber 111 to maintain the airtightness of the interior of the processing container 110. The seal 113 is, for example, an O-ring. Moreover, by making the first chamber 111 and the second chamber 112 abut each other, a closed space is formed inside the processing container 110.

[0075] The first chamber 111 is supported by a support plate 114 provided on the upper surface of the first chamber 111. Furthermore, the support plate 114 is supported by a chamber lifting mechanism 140. The chamber lifting mechanism 140 includes pillars 141 and lifting members 142. The pillars 141 and the lifting members 142 are respectively provided at, for example, four locations on the outer periphery of the support plate 114. The pillars 141 are provided so as to extend vertically upward from the base 100. The lifting members 142 support the outer periphery of the support plate 114, and the base end portions of the lifting members 142 are mounted on the pillars 141. Furthermore, the lifting members 142 are lifted and lowered along the pillars 141 by a driving unit (not shown) such as a motor. With the chamber lifting mechanism 140 having such a structure, the first chamber 111 is configured to be freely lifted and lowered. In addition, the front end portions of the four lifting members 142 are supported by the top plate 143.

[0076] Furthermore, in this embodiment, four chamber lifting mechanisms 140 are provided on the outer periphery of the support plate 114. However, the number of chamber lifting mechanisms 140 is not limited to this number. For example, when the outer periphery of the support plate 114 is supported at four locations, the chamber lifting mechanisms 140 may be provided at two locations, and retractable shafts may be provided at the other two locations.

[0077] The second chamber 112 is supported by a support platform 115 mounted on the base 100. In other words, the second chamber 112 is stationary and does not move. The support platform 115 is hollow. Furthermore, a decompression unit 150 is provided in the second chamber 112 to reduce the pressure inside the processing vessel 110. The decompression unit 150 includes an intake pipe 151 for drawing the atmosphere from the processing vessel 110, and an intake device 152, such as a vacuum pump, connected to the intake pipe 151.

[0078] (Structure of the First Holding Part 120 and Its Periphery)

[0079] Next, the first holding portion 120 and its peripheral structure will be described. Figure 8 4 is a cross-sectional view of the first holding portion 120 and its surrounding structure. Figure 9 This is a plan view of the first holding portion 120 and its surroundings as viewed from below. Figure 10 This is a plan view of the first holding portion 120 and its surroundings as viewed from above.

[0080] The first holding unit 120 holds the first substrate W1. It includes an electrostatic chuck 121 and a cooling plate 122. The electrostatic chuck 121 has internal electrodes and a dielectric. It uses the electrostatic force generated by applying a voltage to the internal electrodes to hold the first substrate W1 to its holding surface. The cooling plate 122 is, for example, a water-cooled plate, through which cooling water flows. This cooling plate 122 maintains the first substrate W1 held by the electrostatic chuck 121 at a desired temperature, such as room temperature.

[0081] Two first chuck marks N11 and N12 serving as first holding marks are formed on the lower surface of first holding portion 120. First chuck marks N11 and N12 are formed, for example, on the outer periphery of the lower surface of electrostatic chuck 121, on a Y-axis passing through the center of electrostatic chuck 121. Furthermore, first chuck marks N11 and N12 each have a cross shape. The shapes of first chuck marks N11 and N12 are not limited to a cross; any shape is acceptable.

[0082] Suction cups 123 are provided on the lower surface of the electrostatic chuck 121 to hold the first substrate W1 by suction. For example, suction cups 123 are provided at three locations. Suction cups 123 are connected to a suction mechanism 126 for sucking the first substrate W1 via suction tubes 125 inserted through through-holes 124 formed through the electrostatic chuck 121 and the cooling plate 122. Suction cups 123 and suction tubes 125 are configured to be raised and lowered freely by the suction mechanism 126.

[0083] The first holding portion 120 is supported by the support portion 160 in a suspended position. The support portion 160 provides a gap between the first holding portion 120 and the first chamber 111. The support portion 160 includes a movable plate 161 and a transmission shaft 162. The movable plate 161 is positioned outside the processing container 110 and above the support plate 114. The movable plate 161 has an opening in its center and is annular in shape.

[0084] On the lower surface of movable plate 161, transmission shafts 162 are arranged at approximately evenly spaced locations, for example, on a concentric circle concentric with movable plate 161. Each transmission shaft 162 extends vertically downward from movable plate 161, penetrates support plate 114 and first chamber 111, and is connected to the upper surface of cooling plate 122 of first holding portion 120.

[0085] A bellows 163 is provided on the outer periphery of the transmission shaft 162 to cover the transmission shaft 162. The upper end of the bellows 163 is connected to the lower surface of the movable plate 161, and the lower end of the bellows 163 is connected to the upper surface of the support plate 114. The bellows 163 enables the first holding portion 120, which is provided outside the processing container 110, to be moved from outside to inside the processing container 110 while ensuring the airtightness of the processing container 110.

[0086] Furthermore, a through hole 164 is formed in the support plate 114 and the first chamber 111, and the transmission shaft 162 is inserted through the interior of the through hole 164. Furthermore, as will be described later, the transmission shaft 162 is moved horizontally by the horizontal position adjustment unit 170, and therefore the inner diameter of the through hole 164 is sufficiently larger than the outer diameter of the transmission shaft 162.

[0087] A horizontal position adjustment unit 170 is provided between the lower surface of the movable plate 161 and the upper surface of the support plate 114. Specifically, the horizontal position adjustment unit 170 is provided outside the processing chamber 110. The horizontal position adjustment units 170 are arranged at approximately evenly spaced locations, for example, on a concentric circle concentric with the movable plate 161.

[0088] For example, a UVW stage with U, V, and W axes as drive axes is used as the horizontal position adjustment unit 170. In this case, the horizontal position adjustment unit 170 can move the movable plate 161 in the X-axis, Y-axis, and θ-axis directions. Furthermore, the horizontal movement of the movable plate 161 is transmitted to the first holding unit 120 via the transmission shaft 162, thereby adjusting the horizontal position of the first holding unit 120. As mentioned above, the horizontal position refers to the position in the X-axis, Y-axis, and θ-axis directions, that is, the position and orientation in the horizontal direction.

[0089] A known stage can be used as the UVW stage of the horizontal position adjustment unit 170. The structure of the horizontal position adjustment unit 170 is not limited thereto; for example, an XYθ stage having the X-axis, Y-axis, and θ-axis as drive axes may be used, or a four-axis stage having four drive axes, X1, X2, Y1, and Y2, that drives the XYθ axes on a single plane may be used.

[0090] A vertical position adjuster 180 is provided on the upper surface of the movable plate 161. Specifically, the vertical position adjuster 180 is provided outside the processing chamber 110. The vertical position adjusters 180 are arranged at approximately even intervals, for example, at three locations on a concentric circle concentric with the movable plate 161.

[0091] The vertical position adjustment unit 180 is provided with a drive unit (not shown), such as a motor. The vertical position adjustment unit 180 is connected to the transmission shaft 162 to raise and lower the transmission shaft 162. The raising and lowering of the transmission shaft 162 is transmitted to the first holding unit 120, thereby adjusting the vertical position of the first holding unit 120. Furthermore, by raising and lowering the first holding unit 120 using the three vertical position adjustment units 180, the inclination (horizontality) of the first holding unit 120 can be adjusted.

[0092] A pressurizing unit 190 is provided in the central opening of the movable plate 161, inserted through the opening. Specifically, the pressurizing unit 190 is provided outside the processing chamber 110. The pressurizing unit 190 includes a pressing mechanism 191, a measuring mechanism 192, and a pressurizing rod 193. The pressing mechanism 191, the measuring mechanism 192, and the pressurizing rod 193 are provided in the order shown, starting from the top.

[0093] As the pressing mechanism 191, for example, a hydraulic cylinder is used. When a hydraulic cylinder is used as described above, the space of the device structure can be saved. In addition, the structure of the pressing mechanism 191 is not limited to a hydraulic cylinder, and for example, a pneumatic cylinder (cylinder) can also be used.

[0094] Pressing mechanism 191 is supported by a support plate 194 provided on its upper surface. Furthermore, support plate 194 is supported by a plurality of, for example, three, support posts 195 provided on its lower surface. The upper ends of support posts 195 are connected to the lower surface of support plate 194, while the lower ends of support posts 195 are connected to the upper surface of support plate 114. Support plate 194 has a generally triangular shape when viewed from above. Three support posts 195 are provided at each vertex of support plate 194.

[0095] A load cell, for example, is used as the measuring mechanism 192. The measuring mechanism 192 is disposed between the pressing mechanism 191 and a flange 196 provided at the upper end of the pressing rod 193. The measuring mechanism 192 measures the load applied to the first and second substrates W1, W2 when the pressing mechanism 191 presses the first and second substrates W1, W2. The measurement results of the measuring mechanism 192 are output to the control device 80.

[0096] Pressurizing rod 193 extends vertically downward from flange 196, penetrates support plate 114 and first chamber 111, and connects to the center portion of the upper surface of cooling plate 122 of first retaining portion 120. Furthermore, through-hole 197 is formed in support plate 114 and first chamber 111, and pressurizing rod 193 is inserted through through-hole 197.

[0097] A bellows 198 is provided on the outer periphery of the pressure rod 193 to cover the pressure rod 193. The upper end of the bellows 198 is connected to the lower surface of the flange 196, and the lower end of the bellows 198 is connected to the upper surface of the support plate 114. The bellows 198 ensures the airtightness of the processing container 110 while pressing the first holding portion 120, which is provided from the outside of the processing container 110 to the inside of the processing container 110.

[0098] The pressurizing unit 190 is configured as described above, and the pressurizing rod 193 is moved vertically using the pressing mechanism 191. This causes the first holding unit 120 to approach the second holding unit 130, and the first substrate W1 held by the first holding unit 120 is pressed against the second substrate W2 held by the second holding unit 130. Furthermore, the measuring mechanism 192 is used to measure the loads applied to the first and second substrates W1 and W2.

[0099] (Structure of the Second Holding Part 130 and Its Periphery)

[0100] Next, the second holding portion 130 and its peripheral structure will be described. Figure 11 and Figure 12 4 is a cross-sectional view of the second holding portion 130 and its surrounding structure. Figure 13 This is a plan view of the second holding portion 130 and its surroundings as viewed from above.

[0101] The second holding portion 130 holds the second substrate W2. The second holding portion 130 is arranged vertically opposite the first holding portion 120 and is positioned in the center of the second chamber 112. Furthermore, the suction pipe 151 of the decompression portion 150 is connected to the second chamber 112 outside the second holding portion 130 when viewed from above.

[0102] The second holding unit 130 includes an electrostatic chuck 131 and a cooling plate 132. The electrostatic chuck 131 has internal electrodes and a dielectric, and uses the electrostatic force generated by applying a voltage to the internal electrodes to attract the second substrate W2 to the attraction surface. The cooling plate 132 is, for example, a water-cooled plate, through which cooling water flows. This cooling plate 132 adjusts the temperature of the second substrate W2 held by the electrostatic chuck 131 to a desired level, such as room temperature. These electrostatic chuck 131 and cooling plate 132 have the same structure as the electrostatic chuck 121 and cooling plate 122 of the first holding unit 120.

[0103] Two second chuck marks N21 and N22 are formed on the upper surface of second holding portion 130 as second holding marks. Each of second chuck marks N21 and N22 is formed, for example, on the outer periphery of the upper surface of electrostatic chuck 131, on a Y-axis passing through the center of electrostatic chuck 131. Furthermore, each of second chuck marks N21 and N22 has a cross shape. Furthermore, these second chuck marks N21 and N22 are arranged to face the first chuck marks N11 and N12 formed on first holding portion 120, respectively. The shapes of second chuck marks N21 and N22 are not limited to a cross; any shape is acceptable.

[0104] The second holding portion 130 is provided with, for example, three lift pins 133 for supporting the second substrate W2 (or the superimposed substrate T) from below and thereby lifting and lowering it. The lift pins 133 are inserted through through-holes 134 formed to penetrate the electrostatic chuck 131, the cooling plate 132, and the second chamber 112. The lift pins 133 are configured to be freely raised and lowered by a lift mechanism 135 provided within the support platform 115.

[0105] For example, two fixed imaging units 200 and 201 are provided below the second holding unit 130 and the second chamber 112. As the fixed imaging units 200 and 201, cameras are used respectively.

[0106] The first fixed imaging unit 200 is positioned opposite the first chuck mark N11 and the second chuck mark N21. Furthermore, a first observation window 202 is formed between the first fixed imaging unit 200 and the second chuck mark N21, through the electrostatic chuck 131, the cooling plate 132, and the second chamber 112. The first observation window 202 is formed, for example, of quartz glass. The first observation window 202 ensures the airtightness of the processing vessel 110 without obstructing the imaging performed by the first fixed imaging unit 200. With this structure, the first fixed imaging unit 200 can capture images of the second chuck mark N21 and the first chuck mark N11 through the first observation window 202. Furthermore, the first chuck mark N11 is captured through the second chuck mark N21. Images captured by the first fixed imaging unit 200 are output to the control device 80.

[0107] The second fixed imaging unit 201 and its surroundings have the same structure as the first fixed imaging unit 200. Specifically, the second fixed imaging unit 201 is positioned opposite the first chuck mark N12 and the second chuck mark N22. A second observation window 203 is formed in the electrostatic chuck 131, the cooling plate 132, and the second chamber 112. Furthermore, the second fixed imaging unit 201 can capture images of the second chuck mark N22 and the first chuck mark N12 through the second observation window 203. Images captured by the second fixed imaging unit 201 are output to the control device 80.

[0108] The second cavity 112 is provided with a displacement meter 204. A laser displacement meter is used as the displacement meter 204. The displacement meter 204 is provided at a plurality of locations, for example, three locations, on the outer periphery of the lower surface of the second holding portion 130.

[0109] An observation window 205 is formed in the electrostatic chuck 131, cooling plate 132, and second chamber 112 at a position corresponding to the displacement meter 204. Observation window 205 is formed, for example, of quartz glass. Observation window 205 maintains the airtightness of the processing chamber 110 without obstructing the optical path of the laser beam from the displacement meter 204.

[0110] With this configuration, displacement meter 204 can irradiate the lower surface of electrostatic chuck 121 of first holding portion 120 with laser light through observation window 205 and receive reflected light from electrostatic chuck 121. Furthermore, displacement meter 204 can measure the distance between first holding portion 120 and second holding portion 130. Furthermore, by using three displacement meters 204, the slope of first holding portion 120 can also be measured. The measurement results of displacement meter 204 are output to control device 80.

[0111] Furthermore, the displacement meter 204 is not disposed inside the processing chamber 110 and does not require vacuum treatment. Therefore, an inexpensive displacement meter that can be used in an atmospheric environment can be used as the displacement meter 204 .

[0112] (Structure of the Imaging Units 210 and 211 and Their Periphery)

[0113] Next, the structure of the camera units 210, 211 and their surroundings will be described. Figures 5 to 7 As shown, the two imaging units 210 and 211 are configured to move between the inside and the outside of the processing container 110 .

[0114] Figure 14 It is a plan view schematically showing the structure of the first imaging unit 210 . Figure 15 It is a side view schematically showing the structure of the first imaging unit 210 . Figure 16 2 is an explanatory diagram schematically showing the internal structure of the first camera unit 210. Figure 16 In the figure, the solid arrows represent the imaging paths (first imaging path Q1 and second imaging path Q2) from the camera, and the dotted arrows represent the optical paths (first optical path R1 and second optical path R2) from the light source.

[0115] The first imaging unit 210 includes a first imaging section 220 , a second imaging section 230 , and a common lens section 240 .

[0116] The first imaging unit 220 includes a first camera 221, a first light source 222, a first lens 223, and a first path changing unit 224. Reflectors 222a and 223a are provided within the first light source 222 and the first lens 223, respectively, for changing the first optical path R1 from the first light source 222. A reflector 224a is provided within the first path changing unit 224 for changing the first imaging path Q1 and the first optical path R1 of the first camera 221.

[0117] The second imaging unit 230 also has the same configuration as the first imaging unit 220 . Specifically, the second imaging unit 230 includes a second camera 231 , a second light source 232 , a second lens 233 , and a second path changing unit 234 .

[0118] The common lens portion 240 includes an upper lens 241, a lower lens 242, and a reflector 243. The reflector 243 is arranged so as to be inclined at 45 degrees when viewed from the side. The first imaging path Q1 and the first optical path R1 starting from the first imaging portion 220 are respectively changed in direction vertically upward, from the upper lens 241 toward the vertical upward. In addition, the second imaging path Q2 and the second optical path R2 starting from the second imaging portion 230 are respectively changed in direction vertically downward, from the lower lens 242 toward the vertical downward. In addition, the first imaging path Q1 (first optical path R1) and the second imaging path Q2 (second optical path R2) extend coaxially in the vertical direction.

[0119] The first imaging unit 210 has the above-described configuration. As will be described later, the first imaging unit 220 simultaneously captures the first alignment mark M11, and the second imaging unit 230 simultaneously captures the second alignment mark M21. Furthermore, the first imaging unit 210 simultaneously captures the first suction cup mark N11, and the second suction cup mark N21. Images captured by the first imaging unit 210 are output to the control device 80.

[0120] Here, advantages of the first imaging unit 210 will be described in comparison with conventional imaging units. Figure 17 This is an explanatory diagram schematically illustrating the internal structure of a conventional imaging unit 500. For simultaneous imaging of vertically upward and vertically downward directions, the conventional imaging unit 500 comprises a first imaging unit 510 for imaging vertically upward and a second imaging unit 520 for imaging vertically downward, arranged vertically side by side. The first camera 511 of the first imaging unit 510 has a focal axis, and the first lens 512 is positioned above the first path changing unit 513. The second camera 521 of the second imaging unit 520 has a focal axis, and the second lens 522 is positioned below the second path changing unit 523. In this configuration, the vertical distance L2 between the first substrate W1 and the second substrate W2 is very long, for example, 220 mm.

[0121] In contrast, the first imaging unit 210 of this embodiment has a common lens portion 240, so Figure 16 As shown, the vertical distance L1 between the first substrate W1 and the second substrate W2 can be shortened to, for example, 110 mm. As will be described later, the imaging performed by the first imaging unit 210 is performed with the processing container 110 open, but the distance between the first chamber 111 and the second chamber 112, which are separated at this time, can be reduced. This reduces the distance traveled when the first chamber 111 is subsequently lowered to seal the processing container 110. As a result, positional deviation between the first substrate W1 and the second substrate W2 can be suppressed. Furthermore, processing time can be shortened.

[0122] Furthermore, the first imaging unit 220 , the second imaging unit 230 , and the common lens unit 240 are supported on a support plate 250 , and a portion of the first imaging unit 220 and a portion of the second imaging unit 230 are covered by a cover 251 .

[0123] The second imaging unit 211 also has the same structure as the first imaging unit 210 , that is, includes a first imaging section 220 , a second imaging section 230 , and a common lens section 240 .

[0124] The first imaging unit 210 is further provided with displacement meters 252 and 253. Laser displacement meters are used as the displacement meters 252 and 253. The upper displacement meter 252 measures the thickness of the upper portion, for example, the first substrate W1, and the lower displacement meter 253 measures the thickness of the lower portion, for example, the second substrate W2.

[0125] like Figures 5 to 7 As shown, the joining device 30 includes a first moving mechanism 260 , a second moving mechanism 270 , and a third moving mechanism 280 for moving the imaging units 210 , 211 .

[0126] The first moving mechanism 260 moves the two imaging units 210 and 211 in the X-axis direction (first direction) within the planar region between the first holding portion 120 and the second holding portion 130. The first moving mechanism 260 includes a gate-shaped moving frame 261 that supports the two imaging units 210 and 211 and extends in the Y-axis direction when viewed from above. Furthermore, a pair of guide rails 262 and 262 extending from the negative side to the positive side of the processing container 110 in the X-axis direction are provided on the base 100. The moving frame 261 is mounted on the pair of guide rails 262 and 262. Furthermore, a drive unit (not shown), such as a motor, is provided on the moving frame 261, and the moving frame 261 is configured to be movable along the guide rails 262 extending along the X-axis.

[0127] The second moving mechanism 270 moves the first imaging unit 210 in the Y-axis direction (second direction). The second moving mechanism 270 supports the first imaging unit 210 and is attached to the upper surface of the moving frame 261. The second moving mechanism 270 includes a built-in drive unit such as a motor and is configured to be movable along the moving frame 261.

[0128] The third moving mechanism 280 moves the second imaging unit 211 in the Y-axis direction (second direction). The third moving mechanism 280 supports the second imaging unit 211 and is attached to the upper surface of the moving frame 261. The third moving mechanism 280 includes a built-in drive unit such as a motor and is configured to be movable along the moving frame 261.

[0129] A reference mark portion 290 is provided on the negative side of the processing container 110 in the X-axis direction. Figure 18 1 is a side view schematically showing the structure of reference mark portion 290 . Reference mark portion 290 includes a first reference mark support 291 and a second reference mark support 292 .

[0130] First fiducial mark support 291 is provided on base 100 and has a gate-shaped frame structure extending in the Y-axis direction. First fiducial mark support 291 is larger than moving frame 261 , and moving frame 261 passes inside first fiducial mark support 291 .

[0131] For example, three first fiducial marks S11, S12, and S13 are formed on the lower surface of first fiducial mark support 291. When imaging units 210 and 211, supported by movable frame 261, pass through first fiducial mark support 291, first imaging unit 220 of each imaging unit 210 and 211 captures an image of one of first fiducial marks S11, S12, and S13. The captured image of first imaging unit 220 is output to control device 80. While three first fiducial marks S11, S12, and S13 are provided in this embodiment, it is sufficient to have two or more first fiducial marks for the first imaging unit 220 of each imaging unit 210 and 211 to capture.

[0132] Second fiducial mark supports 292 are provided on base 100 so as to extend vertically upward. Three second fiducial mark supports 292 are provided below each of first fiducial marks S11, S12, and S13. Second fiducial mark supports 292 are provided inside movable frame 261, which passes over first fiducial mark supports 291.

[0133] Second fiducial marks S21, S22, and S23 are formed on the top surfaces of each of the three second fiducial mark supports 292. Specifically, second fiducial marks S21, S22, and S23 are arranged so as to face first fiducial marks S11, S12, and S13, respectively. Furthermore, when imaging units 210 and 211, supported by movable frame 261, pass through second fiducial mark supports 292, second imaging units 230 of each imaging unit 210 and 211 capture an image of one of second fiducial marks S21, S22, and S23. The captured image of second imaging unit 230 is output to control device 80.

[0134] Furthermore, the first imaging unit 220 simultaneously captures the first fiducial markers S11, S12, and S13, and the second imaging unit 230 simultaneously captures the second fiducial markers S21, S22, and S23. Furthermore, as will be described later, the postures (orientations) of the imaging units 210 and 211 are adjusted based on the captured images of the fiducial markers.

[0135] <Operation of Joint System 1>

[0136] Next, a description will be given of a process of joining the substrates W1 and W2 using the joining system 1 configured as described above. Figure 19 This is a flowchart showing the main steps of the substrate bonding process.

[0137] First, a cassette Cw1 containing a plurality of first substrates W1, a cassette Cw2 containing a plurality of second substrates W2, and an empty cassette Ct are placed on the desired cassette placement plates 11 of the loading / unloading station 2. The first substrates W1 in the cassette Cw1 are then removed by the substrate transport device 22 and transported to the conveyor device 60 of the third processing block G3 of the processing station 3.

[0138] Next, the first substrate W1 is transferred to the load lock chamber 42 of the second processing block G2 by the substrate transfer device 71. The load lock chamber 42 is then sealed and depressurized. Next, the first substrate W1 is transferred to the reforming device 40 by the substrate transfer device of the transfer chamber 41.

[0139] In the modification device 40, oxygen or nitrogen as a processing gas is excited to plasma in a desired reduced pressure atmosphere, thereby ionizing it. The oxygen ions or nitrogen ions are irradiated onto the bonding surface W1a of the first substrate W1, thereby performing plasma treatment on the bonding surface W1a. Then, the bonding surface W1a of the first substrate W1 is modified ( Figure 19 Step A1).

[0140] Next, the first substrate W1 is transferred to the load lock chamber 42 by the substrate transfer device of the transfer chamber 41 . The load lock chamber 42 is then sealed and opened to the atmosphere. Next, the first substrate W1 is transferred to the hydrophilization device 50 by the substrate transfer device 71 .

[0141] In the hydrophilizing device 50, pure water is supplied to the first substrate W1 while rotating the first substrate W1 held by the rotary chuck. As a result, the supplied pure water diffuses on the bonding surface W1a of the first substrate W1, and hydroxyl groups (silanol groups) adhere to the bonding surface W1a of the first substrate W1 modified in the modifying device 40, thereby hydrophilizing the bonding surface W1a. In addition, the bonding surface W1a of the first substrate W1 is cleaned by the pure water. Figure 19 Step A2).

[0142] Next, the horizontal orientation of the first substrate W1 is adjusted by adjusting the position of the orientation plane or the notch. Furthermore, the top and bottom surfaces of the first substrate W1 are flipped so that the bonding surface W1a of the first substrate W1 faces downward. This horizontal orientation adjustment and flipping of the top and back surfaces of the first substrate W1 are performed by a device (not shown) located within the bonding system 1.

[0143] Next, the first substrate W1 is transported to the bonding device 30 of the first processing block G1 by the substrate transport device 71. At this time, the first chamber 111 and the second chamber 112 are separated, and the processing container 110 is opened. The first substrate W1 is delivered to the suction cup 123 that is previously waiting at a position lower than the electrostatic suction cup 121 of the first holding portion 120 with the bonding surface W1a facing downward. Then, the suction cup 123 is raised, as shown in FIG. Figure 20 As shown, the first substrate W1 is held on the electrostatic chuck 121 ( Figure 19 Step A3).

[0144] While the first substrate W1 is being processed in steps A1 to A3 , the second substrate W2 is processed subsequent to the first substrate W1 . First, the second substrate W2 is taken out of the cassette Cw2 by the substrate transfer device 22 and transferred to the conveyor device 60 of the processing station 3 .

[0145] Next, the second substrate W2 is transferred to the load lock chamber 42 by the substrate transfer device 71, and is then transferred to the modification device 40 by the substrate transfer device of the transfer chamber 41. In the modification device 40, the bonding surface W2a of the second substrate W2 is modified ( Figure 19 In addition, the modification of the bonding surface W2a of the second substrate W2 in step A4 is the same as that in the above-mentioned step A1.

[0146] Next, the second substrate W2 is transferred to the load lock chamber 42 by the substrate transfer device of the transfer chamber 41, and is then transferred to the hydrophilization device 50 by the substrate transfer device 71. In the hydrophilization device 50, the bonding surface W2a of the second substrate W2 is hydrophilized and cleaned. Figure 19 In addition, the hydrophilization and cleaning of the bonding surface W2a of the second substrate W2 in step A5 are the same as those in step A2 above.

[0147] Next, regarding the second substrate W2, the horizontal orientation of the first substrate W1 is adjusted by adjusting the position of the orientation plane or the notch. The horizontal orientation adjustment and front and back flipping of the second substrate W2 are performed by a device (not shown) provided in the bonding system 1.

[0148] Next, the second substrate W2 is transported to the bonding device 30 by the substrate transport device 71. The second substrate W2 transported to the bonding device 30 is delivered to the lift pins 133 that are previously positioned above the electrostatic chuck 131 of the second holding portion 130 with the bonding surface W2a facing upward. Next, the lift pins 133 are lowered. Figure 20 As shown, the second substrate W2 is held on the electrostatic chuck 131 ( Figure 19 Step A6).

[0149] Next, the postures (orientations) of the first camera unit 210 and the second camera unit 211 are adjusted ( Figure 19 Step A7).

[0150] In step A7, if Figure 21 As shown, the imaging units 210 and 211 waiting outside the processing container 110 are moved to the positive side of the X-axis to the position of the reference mark portion 290 by the first moving mechanism 260. In the reference mark portion 290, the first imaging unit 220 of the first imaging unit 210 simultaneously captures the first reference mark S11, while the second imaging unit 230 captures the second reference mark S21. The captured image of the first imaging unit 210 is output to the control device 80. In the control device 80, edge detection is performed on the acquired image data, thereby detecting the first reference mark S11 and the second reference mark S21 respectively. In addition, the adjustment mechanism (not shown) of the first imaging unit 210 is controlled so that the first reference mark S11 and the second reference mark S21 are aligned. In addition, the posture (orientation) of the first imaging unit 210 is adjusted by the adjustment mechanism.

[0151] Furthermore, in step A7, the posture (orientation) of the second imaging unit 211 is adjusted using the same method as described above for the first imaging unit 210. By adjusting the postures of the imaging units 210 and 211 in this manner, the imaging accuracy of the imaging units 210 and 211 can be improved. Consequently, the accuracy of adjusting the horizontal positions of the substrates W1 and W2 (alignment accuracy) in step A9, described later, can be improved.

[0152] Next, the thickness of the first substrate W1 and the second substrate W2 is measured ( Figure 19 Step A8).

[0153] In step A8, if Figure 21 As shown, the imaging units 210 and 211 are further moved toward the positive X-axis direction and positioned within the processing container 110. Inside the processing container 110, while the first imaging unit 210 is moved from one end of the substrates W1 and W2 to the other end along the X-axis, the thickness of the first substrate W1 and the thickness of the second substrate W2 are measured using the displacement meters 252 and 253, respectively. The measurement results of the displacement meters 252 and 253 are output to the control device 80. The control device 80 uses the thickness of the first substrate W1 and the thickness of the second substrate W2 to manage the interval (gap) between the substrates W1 and W2 when the first substrate W1 and the second substrate W2 are bonded together in step A13, which will be described later.

[0154] Furthermore, in step A8, the horizontality (vertical position) of first holding unit 120 can also be adjusted. Control device 80 measures the horizontality of first holding unit 120 based on the measurement results of displacement meters 252 and 253. Furthermore, three vertical position adjustment units 180 are controlled to horizontalize the suction surface of electrostatic chuck 121 of first holding unit 120. By independently driving these three vertical position adjustment units 180, the three transmission shafts can be raised and lowered independently, thereby adjusting the horizontality of first holding unit 120.

[0155] Next, the horizontal position of the first holding portion 120 is adjusted, and the horizontal positions of the first substrate W1 and the second substrate W2 are adjusted ( Figure 19 Step A9).

[0156] In step A9, if Figure 22 and Figure 23 As shown, the imaging units 210 and 211 are moved in the X-axis direction by the first moving mechanism 260 , and the common lens portion 240 of each imaging unit 210 and 211 is arranged at the X-axis center position of the substrates W1 and W2 .

[0157] Next, the first imaging unit 210 is moved in the positive direction of the Y axis by the second moving mechanism 270, positioning the common lens unit 240 opposite the first alignment mark M11 and the second alignment mark M21. Furthermore, while the first imaging unit 220 captures the first alignment mark M11, the second imaging unit 230 captures the second alignment mark M21. The images captured by the first imaging unit 210 are output to the control device 80. By simultaneously capturing the first alignment mark M11 and the second alignment mark M21, the imaging time can be shortened and the horizontal position adjustment accuracy (alignment accuracy), described later, can be improved.

[0158] Similarly, the third moving mechanism 280 moves the second imaging unit 211 in the negative Y-axis direction, positioning the common lens unit 240 at a position facing the first alignment mark M12 and the second alignment mark M22. Furthermore, while the first imaging unit 220 captures the first alignment mark M12, the second imaging unit 230 captures the second alignment mark M22. The images captured by the second imaging unit 211 are output to the control device 80.

[0159] The control device 80 performs edge detection on the acquired image data, thereby detecting each of the alignment marks M11, M21, M12, and M22. Furthermore, the horizontal position adjustment unit 170 is controlled to align the cross shape of the first alignment mark M11 with the cross shape of the second alignment mark M21, and to align the cross shape of the first alignment mark M12 with the cross shape of the second alignment mark M22. Control of the horizontal position adjustment unit 170 adjusts the horizontal position (horizontal position and orientation) of the first holding unit 120.

[0160] The horizontal position adjusting unit 170 moves the first holding unit 120 in the horizontal direction or rotates it around the vertical axis, thereby adjusting the horizontal positions of the first substrate W1 and the second substrate W2.

[0161] As described above, in step A9, the alignment marks M11, M21, M12, and M22 are photographed by the two imaging units 210 and 211, and the horizontal positions of the first and second substrates W1 and W2 are adjusted, thereby improving the accuracy of the adjustment (alignment accuracy). In addition, the adjustment can be performed in a short time.

[0162] Next, the first suction cup marks N11, N12 and the second suction cup marks N21, N22 are detected ( Figure 19 Step A10).

[0163] In step A10, if Figure 23 and Figure 24 As shown, the first camera unit 210 is moved in the positive Y-axis direction by the second moving mechanism 270, positioning the common lens unit 240 of the first camera unit 210 facing the first suction cup mark N11 and the second suction cup mark N21. Furthermore, while the first camera unit 220 captures the first suction cup mark N11, the second camera unit 230 captures the second suction cup mark N21. The images captured by the first camera unit 210 are output to the control device 80.

[0164] Similarly, the third moving mechanism 280 moves the second imaging unit 211 in the negative Y-axis direction, positioning the common lens unit 240 at a position facing the first suction cup mark N12 and the second suction cup mark N22. Furthermore, while the first imaging unit 220 captures the first suction cup mark N12, the second imaging unit 230 captures the second suction cup mark N22. The images captured by the second imaging unit 211 are output to the control device 80.

[0165] Here, before adjusting the horizontal positions of substrates W1 and W2 in step A9, the coordinates (x, y) of the pair of facing suction cup marks N11 and N21 are at the reference coordinates (0, 0). Subsequently, when the first holding unit 120 is moved horizontally in step A9, the suction cup marks N11 and N21 also move, and the coordinates (x, y) of the suction cup marks N11 and N21 are thus (Δx1, Δy1). Similarly, the coordinates (x, y) of the other pair of facing suction cup marks N12 and N22 are (Δx2, Δy2).

[0166] The control device 80 performs edge detection on the acquired image data to detect the suction cup marks N11, N21, N12, and N22. Furthermore, the control device 80 calculates the coordinates (Δx1, Δy1) of the suction cup marks N11 and N21 and the coordinates (Δx2, Δy2) of the suction cup marks N12 and N22. The control device 80 uses these suction cup mark coordinates (Δx1, Δy1) and (Δx2, Δy2) when adjusting the horizontal position of the first holding unit 120 in step A12, described later.

[0167] Furthermore, in this embodiment, the alignment marks M11, M21, M12, and M22 and the suction cup marks N11, N21, N12, and N22 are arranged on the same Y-axis. Therefore, the movement of the imaging units 210 and 211 in step A10 is solely in the Y-axis direction. Furthermore, the distances D between the alignment marks M11, M21, M12, and M22 and the suction cup marks N11, N21, N12, and N22 are small, for example, 20 mm to 30 mm. This minimizes the deviation in posture associated with the movement of the imaging units 210 and 211, thereby improving the imaging accuracy of the imaging units 210 and 211.

[0168] When the above steps A8 to A10 are completed, the first moving mechanism 260 moves the imaging units 210 and 211 in the negative direction of the X axis and withdraws them to the outside of the processing container 110. Figure 23 As shown, the first camera unit 210 moves in a first area B1 on the positive side of the Y axis and takes pictures, and the second camera unit 211 moves in a second area B2 on the negative side of the Y axis and takes pictures.

[0169] Next, the processing container 110 is sealed, and the interior of the processing container 110 is depressurized to a desired vacuum level ( Figure 19 Step A11).

[0170] In step A11, if Figure 25As shown, the first chamber 111 is lowered by the chamber lifting mechanism 140, so that the first chamber 111 and the second chamber 112 abut against each other. This forms a sealed space within the processing container 110. The suction device 152 of the decompression unit 150 is then activated to reduce the pressure within the processing container 110. This maintains the interior of the processing container 110 at a desired vacuum level of, for example, 1 Pa or less.

[0171] When the imaging units 210 and 211 are used as described above, the vertical distance L1 between the first substrate W1 and the second substrate W2 is short, thereby reducing the distance traveled when the first chamber 111 is lowered. Consequently, the horizontal positional deviation of the first holding portion 120 caused by the lowering of the first chamber 111 can be suppressed. Furthermore, the time required for step A11 can be shortened.

[0172] Next, adjust the horizontal position of the first holding portion 120 ( Figure 19 In step A12, the pressure inside the processing container 110 is reduced in step A11, causing pressure fluctuations. This impact slightly deviates the horizontal position of the first holding unit 120 adjusted in step A9. Therefore, the horizontal position of the first holding unit 120 is adjusted again.

[0173] In step A12 , the first fixed imaging unit 200 captures the first suction cup mark N11 and the second suction cup mark N21 , and the second fixed imaging unit 201 captures the first suction cup mark N12 and the second suction cup mark N22 . The images captured by the fixed imaging units 200 and 201 are output to the control device 80 .

[0174] In the control device 80, edge detection is performed on the acquired image data, thereby detecting the suction cup marks N11, N21, N12, and N22 respectively. In addition, the coordinates (Δx1, Δy1) of the suction cup marks N11 and N21 and the coordinates (Δx2, Δy2) of the suction cup marks N12 and N22 acquired in the above-mentioned step A10 are restored. That is, Figure 26 As shown, the horizontal position adjustment unit 170 is controlled so that the suction cup marks N11 and N21 are located at the coordinates (Δx1, Δy1), and the suction cup marks N12 and N22 are located at the coordinates (Δx2, Δy2). By controlling the horizontal position adjustment unit 170, the horizontal position (the horizontal position and orientation) of the first holding unit 120 is adjusted.

[0175] Next, the first substrate W1 and the second substrate W2 are bonded ( Figure 19 Step A13).

[0176] In step A13, if Figure 27As shown, the first holding portion 120 is lowered using the three vertical position adjustment portions 180 to bring the first substrate W1 into contact with the second substrate W2. At this time, the control device 80 controls the distance between the first substrate W1 and the second substrate W2 while taking into account the thicknesses of the first substrate W1 and the second substrate W2 measured in step A8.

[0177] In steps A1 and A4, the bonding surface W1a of the first substrate W1 and the bonding surface W2a of the second substrate W2 are modified, thereby generating van der Waals forces (intermolecular forces) between the bonding surfaces W1a and W2a, thereby bonding the bonding surfaces W1a and W2a to each other. Furthermore, in steps A2 and A5, the bonding surface W1a of the first substrate W1 and the bonding surface W2a of the second substrate W2 are hydrophilized, thereby generating hydrogen bonds (intermolecular forces) between the hydrophilic groups between the bonding surfaces W1a and W2a, thereby bonding the bonding surfaces W1a and W2a to each other.

[0178] Next, the first substrate W1 and the second substrate W2 are pressed to further firmly bond them ( Figure 19 Step A14).

[0179] In step A14, if Figure 28 As shown, the pressing mechanism 191 of the pressing portion 190 is used to move the pressing rod 193 in the vertical direction. This causes the first holding portion 120 to approach the second holding portion 130, pressing the first substrate W1 held by the first holding portion 120 against the second substrate W2 held by the second holding portion 130. Furthermore, at this time, the load applied to the first and second substrates W1, W2 is measured using the measuring mechanism 192. The pressing load is, for example, 30 kN. Furthermore, by pressing the first and second substrates W1, W2, the first and second substrates W1, W2 are further firmly bonded to form a superimposed substrate T.

[0180] Figure 29 : is an explanatory diagram showing the load condition when pressing the first substrate W1 and the second substrate W2. As mentioned above, the pressing load P1 of the pressurizing portion 190 is 30 kN. On the other hand, a pressure differential load P2 of 18 kN is applied to the upper surface of the support plate 114 of the processing container 110, which is the atmospheric pressure outside the processing container 110 and the vacuum pressure inside the processing container 110. In this way, the load actually applied to the processing container 110 is 12 kN, which is obtained by subtracting the pressure differential load P2 from the pressing load P1. The reaction force P3 generated by the chamber lifting mechanism 140 is used to bear this 12 kN. Therefore, in this embodiment, the pressing load P1 can be borne in a manner that does not apply a load to the processing container 110.

[0181] Even when the first substrate W1 and the second substrate W2 are pressed in this manner, no load is applied to the movable plate 161 of the support portion 160. The reason for this will be described below.

[0182] The first holding portion 120 is supported by the transmission shaft 162 in a state of being suspended from above. In addition, the first holding portion 120 can be pressed from above by the pressure portion 190, and the transmission shaft 162 can release the pressure. Here, when the first holding portion 120 is pressed in a state where the first substrate W1 and the second substrate W2 are in contact, the first holding portion 120 may be deformed. When the first holding portion 120 is deformed, stress is applied to the movable plate 161 via the transmission shaft 162. In this regard, for example, if the motor of the vertical position adjustment portion 180 is stopped, the transmission shaft 162 and the movable plate 161 become free in the vertical direction. In this way, the movable plate 161 and the first holding portion 120 are independent of each other in the vertical direction, so no load is applied to the movable plate 161. In addition, since no load is applied to the movable plate 161, of course, no load is applied to the horizontal position adjustment portion 170.

[0183] Therefore, in the bonding apparatus 30 of the present embodiment, it is possible to simultaneously achieve high-load bonding processing by the pressurizing portion 190 and high-precision alignment by the horizontal position adjusting portion 170 via the supporting portion 160 .

[0184] Next, the processing container 110 is opened and the interior of the processing container 110 is set to atmospheric pressure ( Figure 19 Step A15).

[0185] In step A15, if Figure 30 As shown, the first chamber 111 is raised by the chamber elevating mechanism 140, opening the processing container 110. At this point, the electrostatic chuck 121 of the first holding unit 120 stops attracting and holding the first substrate W1, and the vertical position adjusting unit 180 raises the first holding unit 120. Furthermore, the pressing unit 190 stops pressing.

[0186] Next, the electrostatic chuck 131 of the second holding portion 130 stops adsorbing and holding the second substrate W2 (overlapping substrate T), and then the overlapping substrate T is lifted from the electrostatic chuck 131 by the lifting pins 133. Figure 31 As shown, the superimposed substrate T is delivered from the lift pins 133 to the substrate transfer device 71 and is carried out from the bonding device 30 .

[0187] Next, the superimposed substrate T is transported to the conveyor 61 by the substrate transport device 71 and then transported to the desired cassette Ct on the cassette mounting plate 11 by the substrate transport device 22 of the loading / unloading station 2. In this way, a series of bonding processes for the substrates W1 and W2 are completed.

[0188] According to the above embodiment, the horizontal positions of the first substrate W1 and the second substrate W2 can be appropriately adjusted in step A9, thereby improving the bonding accuracy when bonding the first substrate W1 and the second substrate W2 in step A13. In addition, the productivity of the bonding process can be improved.

[0189] In the above embodiment, after the first substrate W1 and the second substrate W2 are bonded together in step A13, the first substrate W1 and the second substrate W2 are pressed together in step A14. However, if sufficient bonding strength can be achieved in step A13, step A14 may be omitted. In this case, the pressurizing unit 190 may also be omitted.

[0190] Alternatively, the pressurizing portion 190 may be omitted and a striker may be provided to lower only the center of the upper surface of the first holding portion 120. In this case, while the first substrate W1 is warped convexly downward, the center of the first substrate W1 is brought into contact with the center of the second substrate W2. Bonding is then performed sequentially from the center of the substrates toward the periphery.

[0191] In the above embodiment, an example in which the pressurizing portion 190 presses the first holding portion 120 vertically downward has been described. However, the pressurizing portion 190 may press the second holding portion 130 vertically upward.

[0192] In the above embodiment, the alignment mechanism composed of the support portion 160 , the horizontal position adjustment portion 170 , and the vertical position adjustment portion 180 is provided in the first holding portion 120 , but may be provided in the second holding portion 130 .

[0193] In addition, in the above embodiment, the first holding portion 120 is arranged at the top and the second holding portion 130 is arranged at the bottom, but the arrangement of the first holding portion 120 and the second holding portion 130 may be reversed. Furthermore, in the above embodiment, the first holding portion 120 is configured to be movable in the vertical direction, but the second holding portion 130 may also be movable in the vertical direction, or both the first holding portion 120 and the second holding portion 130 may be movable in the vertical direction.

[0194] In addition, in the above embodiment, the first substrate W1 and the second substrate W2 are bonded together in a vacuum atmosphere, but the present embodiment can also be applied to a case where bonding is performed in an air atmosphere.

[0195] The embodiments disclosed herein are to be considered in all respects as illustrative and non-restrictive. The embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope of the appended claims and the spirit thereof.

[0196] In addition, the following structures also belong to the technical scope of the present disclosure.

[0197] (1) A joining device for joining a first substrate to a second substrate, the joining device comprising: a first holding portion for holding the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged opposite to the first holding portion; two camera units, the two camera units having a first camera unit and a second camera unit, the first camera unit photographing a first alignment mark formed on the joining surface of the first substrate, and the second camera unit photographing a second alignment mark formed on the joining surface of the second substrate; a first moving mechanism for moving the two camera units along a first direction within a planar area between the first holding portion and the second holding portion; a second moving mechanism for moving the first camera unit of the two camera units along a second direction orthogonal to the first direction; and a third moving mechanism for moving the second camera unit of the two camera units along the second direction.

[0198] (2) The bonding device described in (1) further includes a control unit that controls the first moving mechanism, the second moving mechanism, and the third moving mechanism so that the first camera unit captures the first area and the second camera unit captures the second area.

[0199] (3) In the bonding device described in (1) or (2), the camera unit has a reflector, which changes the first optical axis of the first camera part to the first substrate side, and changes the second optical axis of the second camera part to the second substrate side and changes it to be coaxial with the first optical axis.

[0200] (4) In the bonding device described in any one of (1) to (3), the first imaging unit images a first holding mark formed on the first holding unit, and the second imaging unit images a second holding mark formed on the second holding unit.

[0201] (5) The joining device described in (4) further comprises: a processing container for accommodating the first holding portion and the second holding portion; and a fixed camera portion for photographing the first holding mark and the second holding mark from outside the processing container.

[0202] (6) In the joining device described in any one of (1) to (5), there are: a first reference mark, which is set at a position separated from the first holding portion and the second holding portion in the first direction when viewed from above, and the first reference mark is photographed by the first camera unit; and a second reference mark, which is set opposite to the first reference mark, and the second reference mark is photographed by the second camera unit.

[0203] (7) A joining system for joining a first substrate and a second substrate, the joining system comprising: a processing station comprising a joining device for joining the first substrate and the second substrate; and a loading and unloading station for loading and unloading the first substrate, the second substrate, or a superimposed substrate formed by joining the first substrate and the second substrate relative to the processing station, wherein the joining device comprises: a first holding portion for holding the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged opposite to the first holding portion; two camera units, the two camera units comprising a first camera unit and a second camera unit, the first camera unit photographing a first alignment mark formed on the joining surface of the first substrate, and the second camera unit photographing a second alignment mark formed on the joining surface of the second substrate; a first moving mechanism for moving the two camera units along a first direction within a planar area between the first holding portion and the second holding portion; a second moving mechanism for moving the first of the two camera units along a second direction orthogonal to the first direction; and a third moving mechanism for moving the second of the two camera units along the second direction.

[0204] (8) A joining method is a joining method for joining a first substrate and a second substrate using a joining device, wherein the joining device comprises: a first holding portion for holding the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged opposite to the first holding portion; two camera units, the two camera units having a first camera unit and a second camera unit, the first camera unit photographing a first alignment mark formed on the joining surface of the first substrate, and the second camera unit photographing a second alignment mark formed on the joining surface of the second substrate; a first moving mechanism for moving the two camera units along a first direction within a planar area between the first holding portion and the second holding portion; a second moving mechanism for moving the first camera unit of the two camera units along a second direction orthogonal to the first direction; and a third moving mechanism for moving the second camera unit of the two camera units along the second direction orthogonal to the first direction. The bonding method includes the following steps: step (a), holding the first substrate by the first holding portion; step (b), holding the second substrate by the second holding portion; step (c), moving the first camera unit and the second camera unit in the first direction by the first moving mechanism; step (d), moving the first camera unit in the second direction by the second moving mechanism; step (e), moving the second camera unit in the second direction by the third moving mechanism; step (f), photographing the first alignment mark and the second alignment mark by the first camera unit and the second camera unit respectively; and step (g), adjusting the horizontal positions of the first substrate held by the first holding portion and the second substrate held by the second holding portion based on the image photographed by step (f).

[0205] (9) In the joining method described in (8), in the step (d), the first camera unit is moved in the first area, in the step (e), the second camera unit is moved in the second area, and in the step (f), the first area is photographed by the first camera unit, and the second area is photographed by the second camera unit.

[0206] (10) In the bonding method described in (8) or (9), the camera unit has a reflector, which changes the first camera path of the first camera part toward the first substrate side, and changes the second camera path of the second camera part toward the second substrate side and changes it to be coaxial with the first camera path. In the step (f), the first alignment mark and the second alignment mark are simultaneously photographed by the camera unit.

[0207] (11) In the joining method described in any one of (8) to (10), after the step (g), the first camera unit is moved in the second direction by the second moving mechanism, and the second camera unit is moved in the second direction by the third moving mechanism. In each of the first camera unit and the second camera unit, the first holding mark formed on the first holding portion is photographed by the first camera part, and the second holding mark formed on the second holding portion is photographed by the second camera part.

[0208] (12) In the joining method described in any one of (8) to (11), the joining device comprises: a first reference mark, which is set at a position separated from the first camera unit and the second camera unit in the first direction when viewed from above, and the first reference mark is photographed by the first camera unit; and a second reference mark, which is set opposite to the first reference mark, and the second reference mark is photographed by the second camera unit. In the step (c), the first reference mark is photographed by the first camera unit, and the second reference mark is photographed by the second camera unit.

[0209] Description of Reference Numerals

[0210] 30: Joining device; 120: First holding portion; 130: Second holding portion; 210: First camera unit; 211: Second camera unit; 220: First camera unit; 230: First camera unit; 260: First moving mechanism; 270: Second moving mechanism; 280: Third moving mechanism; W1: First substrate; W2: Second substrate.

Claims

1. A bonding device for bonding a first substrate to a second substrate, the bonding device comprising: a first holding portion that holds the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged to face the first holding portion; a first displacement meter for measuring the thickness of the first substrate; a second displacement meter for measuring the thickness of the second substrate; as well as A first moving mechanism moves the first displacement gauge and the second displacement gauge along a first direction within a planar region between the first holding portion and the second holding portion.

2. The joining device according to claim 1, wherein: A first imaging unit is provided, wherein the first imaging unit includes a first imaging portion and a second imaging portion, wherein the first imaging portion photographs a first alignment mark formed on the bonding surface of the first substrate, and the second imaging portion photographs a second alignment mark formed on the bonding surface of the second substrate, The first displacement meter and the second displacement meter are provided on the first camera unit.

3. The joining device according to claim 2, characterized in that A second moving mechanism is provided for moving the first imaging unit in a second direction perpendicular to the first direction.

4. The joining device according to claim 3, characterized in that while moving the first displacement gauge and the second displacement gauge in a first direction, measuring the thickness of the first substrate and the thickness of the second substrate; adjusting the horizontality of the first holding portion based on the measurement results of the thickness of the first substrate and the thickness of the second substrate, The bonding apparatus includes a control unit that controls the first imaging unit, the first moving mechanism, and the second moving mechanism to move the first imaging unit in a second direction and to cause the first imaging unit and the second imaging unit to capture images of the first alignment mark and the second alignment mark.

5. The joining device according to any one of claims 2 to 4, characterized in that: have: a second imaging unit including a first imaging unit and a second imaging unit, wherein the first imaging unit images a first alignment mark formed on the bonding surface of the first substrate, and the second imaging unit images a second alignment mark formed on the bonding surface of the second substrate; as well as A third moving mechanism moves the second imaging unit in a second direction orthogonal to the first direction.

6. A bonding system for bonding a first substrate to a second substrate, the bonding system comprising: a processing station including a bonding device for bonding the first substrate and the second substrate; as well as a loading and unloading station for loading and unloading the first substrate, the second substrate, or a superimposed substrate formed by bonding the first substrate and the second substrate relative to the processing station; Wherein, the joining device comprises: a first holding portion that holds the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged to face the first holding portion; a first displacement meter for measuring the thickness of the first substrate; a second displacement meter for measuring the thickness of the second substrate; and A first moving mechanism moves the first displacement gauge and the second displacement gauge along a first direction within a planar region between the first holding portion and the second holding portion.

7. A bonding method comprising bonding a first substrate and a second substrate using a bonding apparatus. The engaging device comprises: a first holding portion that holds the first substrate; a second holding portion for holding the second substrate, the second holding portion being arranged to face the first holding portion; a first displacement meter for measuring the thickness of the first substrate; a second displacement meter for measuring the thickness of the second substrate; as well as a first moving mechanism that moves the first displacement gauge and the second displacement gauge along a first direction within a planar region between the first holding portion and the second holding portion; The joining method The process includes the following steps: Step (a), holding the first substrate by the first holding portion; Step (b), holding the second substrate by the second holding portion; In step (c), the first displacement gauge and the second displacement gauge are moved in the first direction by the first moving mechanism to measure the thickness of the first substrate and the thickness of the second substrate.

8. The bonding method according to claim 7, wherein: The engaging device comprises: a first imaging unit including a first imaging unit, a second imaging unit, the first displacement meter, and the second displacement meter, wherein the first imaging unit images a first alignment mark formed on the bonding surface of the first substrate, and the second imaging unit images a second alignment mark formed on the bonding surface of the second substrate; as well as a second moving mechanism that moves the first camera unit in a second direction orthogonal to the first direction; The bonding method includes the following steps: (d) adjusting the horizontality of the first holding portion based on the thickness of the first substrate and the thickness of the second substrate measured in (c); Step (e), moving the first imaging unit in a second direction by the second moving mechanism; as well as In step (f), the first imaging unit and the second imaging unit are used to capture images of the first alignment mark and the second alignment mark.

Images