JP7544446B2 - Bonding device and bonding method - Google Patents

Description

This disclosure relates to a joining device and a joining method.

The bonding device described in Patent Document 1 includes a first holding unit, a second holding unit, a striker, a moving unit, and a temperature adjustment unit. The first holding unit adsorbs and holds the first substrate from above. The second holding unit adsorbs and holds the second substrate from below. The striker presses the center of the first substrate from above to bring it into contact with the second substrate. The moving unit moves the second holding unit between a non-facing position where it does not face the first holding unit and a facing position where it faces the first holding unit. The temperature adjustment unit faces the second holding unit arranged in the non-facing position, and locally adjusts the temperature of the second substrate adsorbed and held by the second holding unit.

JP 2018-190817 A

One aspect of the present disclosure provides a technique for reducing distortion between substrates that occurs after bonding warped substrates.

A bonding apparatus according to an aspect of the present disclosure bonds a bonding surface of a first substrate and a bonding surface of a second substrate facing each other to produce a laminated substrate including the first substrate and the second substrate. The bonding apparatus includes a first holding unit, a second holding unit, a pressing unit, a temperature adjustment unit, and a control unit. The first holding unit holds the first substrate from above. The second holding unit holds the second substrate from below. The pressing unit presses down the center of the first substrate, which is spaced apart from the second substrate, to contact the second substrate. The temperature adjustment unit adjusts the temperature distribution of the first substrate or the second substrate before bonding. The control unit controls the temperature adjustment unit based on at least one of the warping of the first substrate and the second substrate before bonding and the distortion occurring between the first substrate and the second substrate after bonding . The bonding apparatus includes a measurement unit that measures the warping of the first substrate or the second substrate before bonding.

According to one aspect of the present disclosure, it is possible to reduce the distortion between substrates that occurs after bonding substrates that have warping.

FIG. 1 is a plan view showing a joining device according to an embodiment. FIG. 2 is a front view of the joining device of FIG. FIG. 3 is a side view showing an example of the first substrate and the second substrate. FIG. 4 is a flow chart illustrating a bonding method according to one embodiment. FIG. 5 is a side view showing an example of the first position adjustment device. FIG. 6A is a side view showing an example of a first temperature adjustment device, and FIG. 6B is a view showing the substrate holding surface of the first temperature adjustment device of FIG. 6A as viewed from below. FIG. 7 is a plan view showing an example of a joining module. FIG. 8 is a side view of the interface module of FIG. FIG. 9 is a cross-sectional view showing an example of an upper chuck and a lower chuck. FIG. 10 is a flow chart showing the details of step S109 in FIG. FIG. 11(A) is a side view showing an example of the operation in step S112, FIG. 11(B) is a side view showing the operation following FIG. 11(A), and FIG. 11(C) is a side view showing the operation following FIG. 11(B). 12A is a cross-sectional view showing an example of the operation in step S113, FIG. 12B is a cross-sectional view showing an example of the operation in step S114, and FIG. 12C is a cross-sectional view showing an operation following FIG. 12B. FIG. 13(A) is a perspective view showing an example of warping, FIG. 13(B) is a plan view showing the distortion caused after bonding due to the warping of FIG. 13(A), FIG. 13(C) is a plan view showing temperature control for reducing the distortion of FIG. 13(B), and FIG. 13(D) is a plan view showing the stress caused by the temperature control of FIG. 13(C). FIG. 14(A) is a perspective view showing another example of warping, FIG. 14(B) is a plan view showing the distortion caused after bonding due to the warping of FIG. 14(A), FIG. 14(C) is a plan view showing temperature control for reducing the distortion of FIG. 14(B), and FIG. 14(D) is a plan view showing the stress caused by the temperature control of FIG. 14(C). FIG. 15A is a perspective view showing an example of warping of the lower wafer, and FIG. 15B is a plan view showing an example of suction pressure distribution of the lower wafer.

Embodiments of the present disclosure will be described below with reference to the drawings. Note that the same or corresponding configurations in each drawing are given the same reference numerals, and descriptions thereof may be omitted. In addition, the X-axis direction, the Y-axis direction, and the Z-axis direction are mutually perpendicular directions, the X-axis direction and the Y-axis direction are horizontal directions, and the Z-axis direction is vertical.

First, the bonding apparatus 1 according to this embodiment will be described with reference to Figs. 1 and 2. As shown in Fig. 3, the bonding apparatus 1 bonds a first substrate W1 and a second substrate W2 to produce a laminated substrate T. At least one of the first substrate W1 and the second substrate W2 is a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer on which multiple electronic circuits are formed. One of the first substrate W1 and the second substrate W2 may be a bare wafer on which no electronic circuits are formed. The first substrate W1 and the second substrate W2 have approximately the same diameter. The compound semiconductor wafer is not particularly limited, but may be, for example, a GaAs wafer, a SiC wafer, a GaN wafer, or an InP wafer.

Hereinafter, the first substrate W1 may be referred to as the "upper wafer W1", the second substrate W2 may be referred to as the "lower wafer W2", and the overlapped substrate T may be referred to as the "overlapped wafer T". As shown in FIG. 3, of the surfaces of the upper wafer W1, the surface that is bonded to the lower wafer W2 is referred to as the "bonding surface W1j", and the surface opposite the bonding surface W1j is referred to as the "non-bonding surface W1n". Also, of the surfaces of the lower wafer W2, the surface that is bonded to the upper wafer W1 is referred to as the "bonding surface W2j", and the surface opposite the bonding surface W2j is referred to as the "non-bonding surface W2n".

As shown in FIG. 1, the joining device 1 includes a loading/unloading station 2 and a processing station 3. The loading/unloading station 2 and the processing station 3 are arranged in the positive direction of the X-axis in the order of the loading/unloading station 2 and the processing station 3. The loading/unloading station 2 and the processing station 3 are also connected together.

The loading/unloading station 2 includes a mounting table 10 and a transfer area 20. The mounting table 10 includes multiple mounting plates 11. Each mounting plate 11 is loaded with a cassette C1, C2, or C3 that stores multiple substrates (e.g., 25 substrates) in a horizontal position. Cassette C1 stores an upper wafer W1, cassette C2 stores a lower wafer W2, and cassette C3 stores a laminated wafer T. In cassettes C1 and C2, the upper wafer W1 and the lower wafer W2 are stored with their bonding surfaces W1j and W2j facing upwards and aligned in the same direction.

The transfer area 20 is disposed adjacent to the mounting table 10 on the positive side of the X-axis. The transfer area 20 is provided with a transfer path 21 extending in the Y-axis direction and a transfer device 22 that can move along the transfer path 21. The transfer device 22 can also move in the X-axis direction and rotate around the Z-axis, and transfers the upper wafer W1, lower wafer W2, and overlapped wafer T between the cassettes C1 to C3 placed on the mounting table 10 and the third processing block G3 of the processing station 3, which will be described later.

The number of cassettes C1 to C3 placed on the mounting table 10 is not limited to that shown in the figure. In addition to the cassettes C1, C2, and C3, cassettes for recovering defective substrates may also be placed on the mounting table 10.

In the processing station 3, for example, three processing blocks G1, G2, and G3 are provided. For example, a first processing block G1 is provided on the rear side of the processing station 3 (the positive Y-axis side in FIG. 1), and a second processing block G2 is provided on the front side of the processing station 3 (the negative Y-axis side in FIG. 1). In addition, a third processing block G3 is provided on the loading/unloading station 2 side of the processing station 3 (the negative X-axis side in FIG. 1).

A transport area 60 is formed in the area surrounded by the first processing block G1 to the third processing block G3. A transport device 61 is disposed in the transport area 60. The transport device 61 has a transport arm that is movable, for example, in the vertical direction, the horizontal direction, and around the vertical axis.

The transfer device 61 moves within the transfer area 60 and transfers the upper wafer W1, the lower wafer W2, and the overlapped wafer T to predetermined devices within the first processing block G1, the second processing block G2, and the third processing block G3 adjacent to the transfer area 60.

In the first processing block G1, for example, a surface modification device 33 and a surface hydrophilization device 34 are arranged. The surface modification device 33 modifies the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2. The surface hydrophilization device 34 hydrophilizes the modified bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2.

For example, the surface modification device 33 breaks the _SiO2 bonds on the bonding surfaces W1j and W2j to form dangling bonds of Si, enabling subsequent hydrophilization. In the surface modification device 33, for example, oxygen gas, which is a processing gas, is excited to be plasmatized and ionized in a reduced pressure atmosphere. Then, the oxygen ions are irradiated onto the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2, whereby the bonding surfaces W1j and W2j are plasma-processed and modified. The processing gas is not limited to oxygen gas, and may be, for example, nitrogen gas or the like.

The surface hydrophilization device 34 hydrophilizes the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2 using a hydrophilization treatment liquid such as pure water. The surface hydrophilization device 34 also has the role of cleaning the bonding surfaces W1j, W2j. In the surface hydrophilization device 34, pure water is supplied onto the upper wafer W1 or the lower wafer W2 while rotating the upper wafer W1 or the lower wafer W2 held by, for example, a spin chuck. As a result, the pure water diffuses onto the bonding surfaces W1j, W2j, and OH groups are attached to the dangling bonds of Si, making the bonding surfaces W1j, W2j hydrophilic.

In the second processing block G2, for example, a bonding module 41, a first temperature adjustment device 42, and a second temperature adjustment device 43 are arranged. The bonding module 41 bonds the hydrophilized upper wafer W1 and the lower wafer W2 to produce a laminated wafer T. The first temperature adjustment device 42 adjusts the temperature distribution of the upper wafer W1 before bonding, i.e., before contact with the lower wafer W2. The second temperature adjustment device 43 adjusts the temperature distribution of the lower wafer W2 before bonding, i.e., before contact with the upper wafer W1. In this embodiment, the first temperature adjustment device 42 and the second temperature adjustment device 43 are provided separately from the bonding module 41, but may be provided as part of the bonding module 41.

In the third processing block G3, for example, a first position adjustment device 51, a second position adjustment device 52, and transition devices 53 and 54 are stacked in this order from top to bottom (see FIG. 2). The locations of the devices in the third processing block G3 are not limited to those shown in FIG. 2. The first position adjustment device 51 adjusts the horizontal orientation of the upper wafer W1, and also turns the upper wafer W1 upside down so that the bonding surface W1j of the upper wafer W1 faces downward. The second position adjustment device 52 adjusts the horizontal orientation of the lower wafer W2. The upper wafer W1 is temporarily placed on the transition device 53. The lower wafer W2 and the overlapped wafer T are temporarily placed on the transition device 54.

The joining device 1 includes a control device 90. The control device 90 is, for example, a computer, and includes a CPU (Central Processing Unit) 91 and a storage medium 92 such as a memory. The storage medium 92 stores programs that control various processes executed in the joining device 1. The control device 90 controls the operation of the joining device 1 by having the CPU 91 execute the programs stored in the storage medium 92.

Next, the joining method of this embodiment will be described with reference to FIG. 4. Steps S101 to S109 shown in FIG. 4 are performed under the control of the control device 90.

First, a cassette C1 containing multiple upper wafers W1, a cassette C2 containing multiple lower wafers W2, and an empty cassette C3 are placed on the placement table 10 of the loading/unloading station 2.

Next, the transfer device 22 removes the upper wafer W1 from the cassette C1 and transfers it to the transition device 53 in the third processing block G3 of the processing station 3. After that, the transfer device 61 removes the upper wafer W1 from the transition device 53 and transfers it to the surface modification device 33 in the first processing block G1.

Next, the surface modification device 33 modifies the bonding surface W1j of the upper wafer W1 (step S101). The modification of the bonding surface W1j is performed with the bonding surface W1j facing upward. Thereafter, the transfer device 61 removes the upper wafer W1 from the surface modification device 33 and transfers it to the surface hydrophilization device 34.

Next, the surface hydrophilization device 34 hydrophilizes the bonding surface W1j of the upper wafer W1 (step S102). The hydrophilization of the bonding surface W1j is performed with the bonding surface W1j facing upward. After that, the transfer device 61 removes the upper wafer W1 from the surface hydrophilization device 34 and transfers it to the first position adjustment device 51 in the third processing block G3.

Next, the first position adjustment device 51 adjusts the horizontal orientation of the upper wafer W1 and turns the upper wafer W1 upside down (step S103). As a result, the notch of the upper wafer W1 is oriented in a predetermined direction, and the bonding surface W1j of the upper wafer W1 faces downward. After that, the transfer device 61 removes the upper wafer W1 from the first position adjustment device 51 and transfers it to the first temperature adjustment device 42 in the second processing block G2.

Next, the first temperature adjustment device 42 adjusts the temperature of the upper wafer W1 (step S104). The temperature adjustment of the upper wafer W1 is performed with the bonding surface W1j of the upper wafer W1 facing downward. Thereafter, the transfer device 61 removes the upper wafer W1 from the first temperature adjustment device 42 and transfers it to the bonding module 41.

In parallel with the above processing of the upper wafer W1, the following processing is performed on the lower wafer W2. First, the transfer device 22 removes the lower wafer W2 from the cassette C2 and transfers it to the transition device 54 in the third processing block G3 of the processing station 3. Then, the transfer device 61 removes the lower wafer W2 from the transition device 54 and transfers it to the surface modification device 33 in the first processing block G1.

Next, the surface modification device 33 modifies the bonding surface W2j of the lower wafer W2 (step S105). The modification of the bonding surface W2j is performed with the bonding surface W2j facing upward. Thereafter, the transfer device 61 removes the lower wafer W2 from the surface modification device 33 and transfers it to the surface hydrophilization device 34.

Next, the surface hydrophilization device 34 hydrophilizes the bonding surface W2j of the lower wafer W2 (step S106). The hydrophilization of the bonding surface W2j is performed with the bonding surface W2j facing upward. Thereafter, the transfer device 61 removes the lower wafer W2 from the surface hydrophilization device 34 and transfers it to the second position adjustment device 52 in the third processing block G3.

Next, the second position adjustment device 52 adjusts the horizontal orientation of the lower wafer W2 (step S107). As a result, the notch of the lower wafer W2 is oriented in a predetermined direction. Thereafter, the transfer device 61 removes the lower wafer W2 from the second position adjustment device 52 and transfers it to the second temperature adjustment device 43 in the second processing block G2.

Next, the second temperature adjustment device 43 adjusts the temperature of the lower wafer W2 (step S108). The temperature adjustment of the lower wafer W2 is performed with the bonding surface W2j of the lower wafer W2 facing upward. Thereafter, the transfer device 61 removes the lower wafer W2 from the second temperature adjustment device 43 and transfers it to the bonding module 41.

Next, the bonding module 41 bonds the upper wafer W1 and the lower wafer W2 to produce a laminated wafer T (step S109). After that, the transfer device 61 removes the laminated wafer T from the bonding module 41 and transfers it to the transition device 54 in the third processing block G3.

Finally, the transfer device 22 removes the laminated wafer T from the transition device 54 and transfers it to the cassette C3 on the mounting table 10. This completes the series of processes.

Next, an example of the first position adjustment device 51 will be described with reference to FIG. 5. The second position adjustment device 52 is configured similarly to the first position adjustment device 51 except that it does not have the base inversion section 51d, and therefore will not be described.

The first position adjustment device 51 has a base 51a, a holding unit 51b that suction-holds and rotates the upper wafer W1, and a detection unit 51c that detects the positions of the notches of the upper wafer W1 and the lower wafer W2. While the holding unit 51b suction-holds and rotates the upper wafer W1, the detection unit 51c detects the position of the notch of the upper wafer W1, thereby adjusting the position of the notch and adjusting the horizontal orientation of the upper wafer W1.

The first position adjustment device 51 also has a base inversion unit 51d that inverts the base 51a. The base inversion unit 51d is equipped with, for example, a motor, and inverts the base 51a upside down, thereby inverting the upper wafer W1 held by the holder 51b upside down. As a result, the bonding surface W1j of the upper wafer W1 faces downward.

Next, an example of the first temperature adjustment device 42 will be described with reference to FIG. 6. The second temperature adjustment device 43 is configured similarly to the first temperature adjustment device 42, except that it holds the lower wafer W2 from below, and therefore will not be described.

As shown in FIG. 6(A), the first temperature adjustment device 42 has a temperature control plate 42a that holds the upper wafer W1 from above. The temperature control plate 42a holds the upper wafer W1 horizontally from above with the bonding surface W1j of the upper wafer W1 facing downward.

As shown in FIG. 6(B), the temperature control plate 42a includes a plurality of elements 42b that locally heat or cool the upper wafer W1. The elements 42b are not particularly limited, but are, for example, Peltier elements. The Peltier elements absorb or generate heat when a current is supplied to them. The direction of the current switches between heat absorption and heat generation. The amount of heat absorption and heat generation is controlled by the magnitude of the current. Note that as long as a temperature difference is generated in the upper wafer W1, the elements 42b that only absorb heat or only generate heat may be used.

The multiple elements 42b are arranged in a planar manner on the lower surface, which is the substrate holding surface, of the temperature control plate 42a. The multiple elements 42b are arranged in the circumferential direction and in multiple concentric rows. However, the arrangement of the elements 42b is not particularly limited. For example, the multiple elements 42b may be arranged in a checkerboard pattern.

The control device 90 controls the elements 42b individually to divide the bonding surface W1j of the upper wafer W1 into multiple regions and adjust the temperature of each region individually. As a result, the temperature distribution of the bonding surface W1j of the upper wafer W1 can be controlled.

Next, an example of the bonding module 41 will be described with reference to Figures 7 to 9. As shown in Figure 7, the bonding module 41 has a processing vessel 210 whose interior can be sealed. A loading/unloading port 211 is formed on the side of the processing vessel 210 facing the transfer area 60, and an opening/closing shutter 212 is provided at the loading/unloading port 211. The upper wafer W1, the lower wafer W2, and the overlapped wafer T are loaded and unloaded through the loading/unloading port 211.

As shown in FIG. 8, an upper chuck 230 and a lower chuck 231 are provided inside the processing vessel 210.
The upper chuck 230 holds the upper wafer W1 from above with the bonding surface W1j of the upper wafer W1 facing downward. The lower chuck 231 is provided below the upper chuck 230 and holds the lower wafer W2 from below with the bonding surface W2j of the lower wafer W2 facing upward.

The upper chuck 230 is supported by a support member 280 provided on the ceiling surface of the processing vessel 210. Meanwhile, the lower chuck 231 is supported by a first lower chuck moving part 291 provided below the lower chuck 231.

The first lower chuck moving part 291 moves the lower chuck 231 in the horizontal direction (Y-axis direction) as described below. The first lower chuck moving part 291 is also configured to be able to move the lower chuck 231 vertically and rotate around a vertical axis.

The first lower chuck moving part 291 is provided on the underside of the first lower chuck moving part 291 and is attached to a pair of rails 295 extending in the horizontal direction (Y-axis direction). The first lower chuck moving part 291 is configured to be movable along the rails 295. The rails 295 are provided on the second lower chuck moving part 296.

The second lower chuck moving part 296 is provided on the underside of the second lower chuck moving part 296 and is attached to a pair of rails 297 extending in the horizontal direction (X-axis direction). The second lower chuck moving part 296 is configured to be movable along the rails 297, i.e., to move the lower chuck 231 in the horizontal direction (X-axis direction). The pair of rails 297 are provided on a mounting table 298 provided on the bottom surface of the processing vessel 210.

The first lower chuck moving part 291 and the second lower chuck moving part 296 constitute the moving mechanism 290. The moving mechanism 290 moves the relative positions of the upper chuck 230 and the lower chuck 231 between the substrate transfer position and the joining position.

The substrate transfer position is a position where the upper chuck 230 receives the upper wafer W1 from the transfer device 61, the lower chuck 231 receives the lower wafer W2 from the transfer device 61, and the lower chuck 231 transfers the overlapped wafer T to the transfer device 61. The substrate transfer position is a position where the overlapped wafer T produced in the nth (n is a natural number equal to or greater than 1) bonding is continuously removed and the upper wafer W1 and lower wafer W2 to be bonded in the n+1th bonding are continuously removed. The substrate transfer position is, for example, the position shown in Figures 7 and 8.

When transferring the upper wafer W1 to the upper chuck 230, the transfer device 61 enters directly below the upper chuck 230. Also, when receiving the overlapped wafer T from the lower chuck 231 and transferring the lower wafer W2 to the lower chuck 231, the transfer device 61 enters directly above the lower chuck 231. To make it easier for the transfer device 61 to enter, the upper chuck 230 and the lower chuck 231 are shifted to the side, and the vertical distance between the upper chuck 230 and the lower chuck 231 is also large.

On the other hand, the bonding position is a position where the upper wafer W1 and the lower wafer W2 are faced with a predetermined distance apart and bonded. The bonding position is, for example, the position shown in FIG. 9. At the bonding position, the distance between the upper wafer W1 and the lower wafer W2 in the vertical direction is narrower than at the substrate transfer position. Also, at the bonding position, unlike the substrate transfer position, the upper wafer W1 and the lower wafer W2 overlap when viewed in the vertical direction.

The moving mechanism 290 moves the relative positions of the upper chuck 230 and the lower chuck 231 in the horizontal direction (both the X-axis direction and the Y-axis direction) and the vertical direction. In this embodiment, the moving mechanism 290 moves the lower chuck 231, but it may move either the lower chuck 231 or the upper chuck 230, or may move both. The moving mechanism 290 may also rotate the upper chuck 230 or the lower chuck 231 around the vertical axis.

As shown in FIG. 9, the upper chuck 230 is partitioned into multiple (e.g., three) regions 230a, 230b, and 230c. These regions 230a, 230b, and 230c are provided in this order from the center of the upper chuck 230 toward the periphery. Region 230a has a circular shape in a plan view, and regions 230b and 230c have annular shapes in a plan view.

Suction pipes 240a, 240b, and 240c are provided independently for each of the regions 230a, 230b, and 230c. Different vacuum pumps 241a, 241b, and 241c are connected to the respective suction pipes 240a, 240b, and 240c. The upper chuck 230 can vacuum-suck the upper wafer W1 for each of the regions 230a, 230b, and 230c.

The upper chuck 230 is provided with a plurality of holding pins 245 that can be raised and lowered vertically. The plurality of holding pins 245 are connected to a vacuum pump 246, and the upper wafer W1 is vacuum-adsorbed by operation of the vacuum pump 246. The upper wafer W1 is vacuum-adsorbed to the lower ends of the plurality of holding pins 245. Ring-shaped suction pads may be used instead of the plurality of holding pins 245.

The multiple holding pins 245 are lowered to protrude from the holding surface of the upper chuck 230. In this state, the multiple holding pins 245 vacuum-suck the upper wafer W1 and receive it from the transfer device 61. The multiple holding pins 245 then rise, and the upper wafer W1 is brought into contact with the holding surface of the upper chuck 230. Next, the upper chuck 230 vacuum-sucks the upper wafer W1 horizontally in each of the regions 230a, 230b, and 230c by operating the vacuum pumps 241a, 241b, and 241c.

A through hole 243 that passes vertically through the upper chuck 230 is formed in the center of the upper chuck 230. A pushing part 250, which will be described later, is inserted into the through hole 243. The pushing part 250 pushes down the center of the upper wafer W1, which is arranged at a distance from the lower wafer W2, and brings it into contact with the lower wafer W2.

The pushing unit 250 has a pushing pin 251 and an outer cylinder 252 that serves as a lifting guide for the pushing pin 251. The pushing pin 251 is inserted into the through hole 243 by a drive unit (not shown) that has a built-in motor, for example, and protrudes from the holding surface of the upper chuck 230 to push down the center of the upper wafer W1.

The lower chuck 231 is partitioned into multiple (e.g., two) regions 231a and 231b. These regions 231a and 231b are provided in this order from the center to the periphery of the lower chuck 231. Region 231a has a circular shape in a plan view, and region 231b has an annular shape in a plan view.

Suction pipes 260a, 260b are provided independently for each region 231a, 231b. Different vacuum pumps 261a, 261b are connected to each suction pipe 260a, 260b. The lower chuck 231 can vacuum-suck the lower wafer W2 for each region 231a, 231b.

The lower chuck 231 is provided with a plurality of holding pins 265 that can be raised and lowered in the vertical direction. The lower wafer W2 is placed on the upper ends of the plurality of holding pins 265. The lower wafer W2 may be vacuum-attached to the upper ends of the plurality of holding pins 265.

The multiple holding pins 265 rise and protrude from the holding surface of the lower chuck 231. In this state, the multiple holding pins 265 receive the lower wafer W2 from the transfer device 61. The multiple holding pins 265 then descend and the lower wafer W2 is brought into contact with the holding surface of the lower chuck 231. Next, the upper chuck 230 horizontally vacuum-adsorbs the lower wafer W2 in each of the regions 231a and 231b by operating the vacuum pumps 261a and 261b.

Next, the details of step S109 in FIG. 4 will be described with reference to FIGS. 10 to 12. First, the transfer device 61 loads the upper wafer W1 and the lower wafer W2 into the bonding module 41 (step S111). During step S111, the relative positions of the upper chuck 230 and the lower chuck 231 are the substrate transfer positions shown in FIGS. 7 and 8.

Next, the moving mechanism 290 moves the relative positions of the upper chuck 230 and the lower chuck 231 from the substrate transfer position shown in FIGS. 7 and 8 to the bonding position shown in FIG. 9 (step S112). In step S112, the upper wafer W1 and the lower wafer W2 are aligned. For the alignment, a first camera S1 and a second camera S2 are used as shown in FIG. 11.

The first camera S1 is fixed to the upper chuck 230 and captures an image of the lower wafer W2 held by the lower chuck 231. A plurality of reference points B1 to B3 are formed in advance on the bonding surface W2j of the lower wafer W2. Patterns of electronic circuits or the like are used as the reference points B1 to B3. The number of reference points can be set arbitrarily.

On the other hand, the second camera S2 is fixed to the lower chuck 231 and captures an image of the upper wafer W1 held by the upper chuck 230. A number of reference points A1 to A3 are formed in advance on the bonding surface W1j of the upper wafer W1. Patterns of electronic circuits or the like are used as the reference points A1 to A3. The number of reference points can be set arbitrarily.

First, as shown in FIG. 11(A), the moving mechanism 290 adjusts the relative horizontal positions of the first camera S1 and the second camera S2. Specifically, the moving mechanism 290 moves the lower chuck 231 horizontally so that the second camera S2 is positioned approximately directly below the first camera S1. Then, the moving mechanism 290 finely adjusts the horizontal position of the second camera S2 so that the first camera S1 and the second camera S2 capture an image of a common target X and the horizontal positions of the first camera S1 and the second camera S2 match.

Next, as shown in FIG. 11(B), the movement mechanism 290 moves the lower chuck 231 vertically upward, and then adjusts the horizontal positions of the upper chuck 230 and the lower chuck 231. Specifically, while the movement mechanism 290 moves the lower chuck 231 horizontally, the first camera S1 sequentially images the reference points B1 to B3 of the lower wafer W2, and the second camera S2 sequentially images the reference points A1 to A3 of the upper wafer W1. Note that FIG. 11(B) shows the first camera S1 imaging the reference point B1 of the lower wafer W2, and the second camera S2 imaging the reference point A1 of the upper wafer W1.

The first camera S1 and the second camera S2 transmit the captured image data to the control device 90. The control device 90 controls the movement mechanism 290 based on the image data captured by the first camera S1 and the image data captured by the second camera S2, and adjusts the horizontal position of the lower chuck 231 so that the reference points A1 to A3 of the upper wafer W1 and the reference points B1 to B3 of the lower wafer W2 coincide with each other when viewed vertically.

Next, as shown in FIG. 11(C), the moving mechanism 290 moves the lower chuck 231 vertically upward. As a result, the gap G (see FIG. 9) between the bonding surface W2j of the lower wafer W2 and the bonding surface W1j of the upper wafer W1 becomes a predetermined distance, for example, 80 μm to 200 μm. A first displacement gauge S3 and a second displacement gauge S4 are used to adjust the gap G.

The first displacement meter S3, like the first camera S1, is fixed to the upper chuck 230 and measures the thickness of the lower wafer W2 held by the lower chuck 231. The first displacement meter S3, for example, irradiates light onto the lower wafer W2, receives light reflected from both the upper and lower surfaces of the lower wafer W2, and measures the thickness of the lower wafer W2. The thickness is measured, for example, when the moving mechanism 290 moves the lower chuck 231 in the horizontal direction. The measurement method of the first displacement meter S3 is, for example, a confocal method, a spectral interference method, or a triangulation method. The light source of the first displacement meter S3 is an LED or a laser.

On the other hand, the second displacement meter S4 is fixed to the lower chuck 231, similar to the second camera S2, and measures the thickness of the upper wafer W1 held by the upper chuck 230. The second displacement meter S4, for example, irradiates light onto the upper wafer W1, receives light reflected from both the top and bottom surfaces of the upper wafer W1, and measures the thickness of the upper wafer W1. The thickness is measured, for example, when the moving mechanism 290 moves the lower chuck 231 in the horizontal direction. The measurement method of the second displacement meter S4 is, for example, a confocal method, a spectral interference method, or a triangulation method. The light source of the second displacement meter S4 is an LED or a laser.

The first displacement gauge S3 and the second displacement gauge S4 transmit the measured data to the control device 90. The control device 90 controls the movement mechanism 290 based on the data measured by the first displacement gauge S3 and the data measured by the second displacement gauge S4, and adjusts the vertical position of the lower chuck 231 so that the gap G becomes the set value.

Next, the operation of the vacuum pump 241a is stopped, and the vacuum suction of the upper wafer W1 in the region 230a is released, as shown in FIG. 12(A). After that, the pushing pin 251 of the pushing part 250 descends, pushing down the center of the upper wafer W1 and bringing it into contact with the lower wafer W2 (step S113). As a result, the centers of the upper wafer W1 and the lower wafer W2 are joined together.

Because the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2 have each been modified, van der Waals forces (intermolecular forces) are first generated between the bonding surfaces W1j and W2j, and the bonding surfaces W1j and W2j are bonded to each other. Furthermore, because the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2 have each been hydrophilized, hydrophilic groups (e.g., OH groups) form hydrogen bonds, and the bonding surfaces W1j and W2j are firmly bonded to each other.

Next, the operation of the vacuum pump 241b is stopped, and the vacuum suction of the upper wafer W1 in the region 230b is released, as shown in FIG. 12(B). Next, the operation of the vacuum pump 241c is stopped, and the vacuum suction of the upper wafer W1 in the region 230c is released, as shown in FIG. 12(C).

In this way, the vacuum suction of the upper wafer W1 is gradually released from the center toward the periphery of the upper wafer W1, and the upper wafer W1 gradually falls and comes into contact with the lower wafer W2. Then, the bonding of the upper wafer W1 and the lower wafer W2 progresses sequentially from the center toward the periphery (step S114). As a result, the bonding surface W1j of the upper wafer W1 and the bonding surface W2j of the lower wafer W2 come into contact over their entire surfaces, the upper wafer W1 and the lower wafer W2 are bonded, and the overlapped wafer T is obtained. The pushing pin 251 is then raised to its original position.

Next, the moving mechanism 290 moves the relative positions of the upper chuck 230 and the lower chuck 231 from the joining position shown in FIG. 9 to the substrate transfer position shown in FIG. 7 and FIG. 8 (step S115). For example, the moving mechanism 290 first lowers the lower chuck 231 to widen the vertical gap between the lower chuck 231 and the upper chuck 230. Next, the moving mechanism 290 moves the lower chuck 231 laterally to shift the lower chuck 231 and the upper chuck 230 laterally.

Next, the transfer device 61 transfers the overlapped wafer T to the bonding module 41 (step S116). Specifically, first, the lower chuck 231 releases the overlapped wafer T. Next, the multiple holding pins 265 rise and transfer the overlapped wafer T to the transfer device 61. After that, the multiple holding pins 265 descend to their original positions.

Next, referring to FIG. 13, an example of distortion caused after bonding due to warping of the lower wafer W2 and temperature distribution control performed before bonding will be described. The distortion caused after bonding refers to, for example, a deviation between a reference point of the upper wafer W1 (e.g., reference points A1 to A3 in FIG. 11) and a reference point of the lower wafer W2 (e.g., reference points B1 to B3 in FIG. 11). The size and direction of the arrow shown in FIG. 13(B) indicate the size and direction of the deviation of the reference point of the upper wafer W1 relative to the reference point of the lower wafer W2. Multiple reference points are set on each of the upper wafer W1 and the lower wafer W2.

In this embodiment, the case where the warpage of the upper wafer W1 is negligibly small compared to the warpage of the lower wafer W2 is described, but the warpage of the upper wafer W1 may be the same as the warpage of the lower wafer W2. In this case, too, the distortion that occurs after bonding can be reduced by adjusting the temperature distribution of the upper wafer W1 or the lower wafer W2 before bonding.

As shown in FIG. 13(A), the lower wafer W2 may warp. The warping of the lower wafer W2 occurs, for example, when multiple films are stacked on a semiconductor substrate such as a silicon wafer. Each film is deposited by a method such as CVD (Chemical Vapor Deposition), ALD (Atomic Layer Deposition), or spin-on. During deposition, stress occurs due to differences in thermal expansion, causing the lower wafer W2 to warp.

The bonding surface W2j of the lower wafer W2 often has a warp that is symmetrical about two reference lines L1 and L2 that intersect at right angles at the center of the bonding surface W2j, that is, an axisymmetric warp. This is because the Young's modulus, Poisson's ratio, and shear modulus of elasticity of a semiconductor substrate such as a silicon wafer change in a 90° cycle. The reference lines L1 and L2 extend in a specific crystal orientation of the semiconductor substrate.

As shown in FIG. 13(A), the lower wafer W2 may warp so that the reference line L1 is a straight line and the reference line L2 is an upwardly convex curve. In this case, when the lower chuck 231 adsorbs the lower wafer W2, the reference line L2 shrinks and becomes parallel to the Y-axis direction. This is because the center of the lower wafer W2 in the Y-axis direction is adsorbed after both ends of the lower wafer W2 in the Y-axis direction are adsorbed.

The upper wafer W1 and the lower wafer W2 may be bonded together while the reference line L2 of the lower wafer W2 is in a shrunk state. As a result, as shown in FIG. 13(B), distortion occurs between the upper wafer W1 and the lower wafer W2 after bonding. Specifically, on the reference line L2, the reference point of the upper wafer W1 is shifted radially outward relative to the reference point of the lower wafer W2.

After bonding, when the lower chuck 231 releases the suction of the lower wafer W2, the reference line L2 of the lower wafer W2 tries to return to its original length. As a result, a tensile stress acts on the reference line L2 of the upper wafer W1, and a compressive stress acts on the reference line L1 of the upper wafer W1 to balance the stresses. Therefore, on the reference line L1, the reference point of the upper wafer W1 shifts radially inward relative to the reference point of the lower wafer W2.

Therefore, the control device 90 controls the first temperature adjustment device 42 or the second temperature adjustment device 43 based on at least one of the warpage of the upper wafer W1 and the lower wafer W2 before bonding and the distortion that occurs between the upper wafer W1 and the lower wafer W2 after bonding. Before bonding, that is, before the upper wafer W1 and the lower wafer W2 come into contact with each other, the temperature distribution of the upper wafer W1 or the lower wafer W2, and thus the dimensions and shape thereof, can be adjusted, and the distortion that occurs after bonding can be reduced.

As shown in Figures 13(A) and 13(B), if the bonding surface W2j of the lower wafer W2 before bonding has an axisymmetric warpage, the distortion between the upper wafer W1 and the lower wafer W2 after bonding will also be axisymmetric. If the warpage or distortion is axisymmetric, the control device 90 may control the temperature distribution of the upper wafer W1 or the lower wafer W2 to be an axisymmetric distribution.

For example, as shown in FIG. 13(C), the elements 42b that adjust the temperature of the upper wafer W1 are controlled in groups Ga to Gc. The groups Ga and Gb are arranged alternately in the circumferential direction and are arranged symmetrically, that is, line-symmetrically, with respect to the two reference lines L1 and L2 of the upper wafer W1. The group Gc is set in a circle at the center of the temperature control plate 42a.

When the reference line L2 of the lower wafer W2 is in a shrunk state before bonding, the elements 42b of group Gb on the reference line L2 absorb heat and locally cool the upper wafer W1 so that the reference line L2 of the upper wafer W1 is also in a shrunk state to the same extent. Meanwhile, the elements 42b of group Ga on the reference line L1 generate heat and locally heat the upper wafer W1. The elements 42b of group Gc do not need to generate heat or absorb heat.

As a result, the dimensions and shape of the upper wafer W1 change as shown by the white arrow in FIG. 13(D). Therefore, the distortion that occurs between the upper wafer W1 and the lower wafer W2 after bonding can be reduced.

In addition, instead of adjusting the temperature distribution of the upper wafer W1, the control device 90 may adjust the temperature distribution of the lower wafer W2 to adjust the dimensions and shape of the lower wafer W2. For example, before adsorbing the lower wafer W2, the control device 90 sets the length of the reference line L2 of the lower wafer W2 to be longer than the length of the reference line L2 of the upper wafer W1. After that, when the lower chuck 231 adsorbs the lower wafer W2 and the reference line L2 of the lower wafer W2 shrinks, it becomes approximately the same length as the reference line L2 of the upper wafer W1. The multiple elements 42b that adjust the temperature of the lower wafer W2 are controlled, for example, as follows. The elements 42b of group Gb on the reference line L2 generate heat and locally heat the lower wafer W2. On the other hand, the elements 42b of group Ga on the reference line L1 absorb heat and locally cool the lower wafer W2. The elements 42b of group Gc do not need to generate or absorb heat.

Next, referring to FIG. 14, we will explain another example of the distortion caused after bonding due to warping of the lower wafer W2 and the control of temperature distribution performed before bonding. As shown in FIG. 14(A), the bonding surface W2j of the lower wafer W2 may have concentric warping. Note that the two reference lines L1 and L2 shown in FIG. 14(A) etc. correspond to the two reference lines L1 and L2 shown in FIG. 13(A) etc., and extend in a specific crystal orientation of the semiconductor substrate.

As shown in FIG. 14(A), the lower wafer W2 may warp so that the reference line L1 is an upward convex curve and the reference line L2 is also an upward convex curve. In this case, when the lower chuck 231 adsorbs the lower wafer W2, the reference line L1 shrinks and becomes parallel to the X-axis direction, and the reference line L2 shrinks and becomes parallel to the Y-axis direction, causing the lower wafer W2 to shrink concentrically. This is because the center of the lower wafer W2 is adsorbed after the periphery of the lower wafer W2 is adsorbed.

The upper wafer W1 and the lower wafer W2 may be bonded together when the two reference lines L1, L2 of the lower wafer W2 are in a shrunk state, i.e., when the lower wafer W2 is in a concentrically shrunk state. As a result, as shown in FIG. 14(B), distortion occurs between the upper wafer W1 and the lower wafer W2 after bonding. Specifically, the reference point of the upper wafer W1 is concentrically shifted relative to the reference point of the lower wafer W2. The magnitude of the shift is greater radially outward.

As shown in Figures 14(A) and 14(B), if the bonding surface W2j of the lower wafer W2 before bonding has a concentric warp, the distortion between the upper wafer W1 and the lower wafer W2 after bonding will also be concentric. If the warp or distortion is concentric, the control device 90 may control the temperature distribution of the upper wafer W1 or the lower wafer W2 to a concentric distribution.

For example, as shown in FIG. 14(C), the elements 42b that adjust the temperature of the upper wafer W1 are controlled in groups Ga to Gc. Groups Ga and Gb are arranged concentrically. Group Gb is set radially outward of group Ga. Group Gc is set in a circle at the center of the temperature control plate 42a.

When the lower wafer W2 is in a concentrically shrunk state before bonding, the elements 42b of the two groups Ga and Gb absorb heat and locally cool the upper wafer W1 so that the upper wafer W1 is also in a concentrically shrunk state to the same extent. The cooling temperature of the two groups Ga and Gb may be the same, or one cooling temperature may be lower than the other. The elements 42b of group Gc may neither generate nor absorb heat.

As a result, the dimensions and shape of the upper wafer W1 change as shown by the white arrow in FIG. 14(D). Therefore, the distortion that occurs between the upper wafer W1 and the lower wafer W2 after bonding can be reduced.

In addition, instead of adjusting the temperature distribution of the upper wafer W1, the control device 90 may adjust the temperature distribution of the lower wafer W2 to adjust the dimensions and shape of the lower wafer W2. For example, before adsorbing the lower wafer W2, the control device 90 sets the diameter of the lower wafer W2 to be longer than the diameter of the upper wafer W1. Thereafter, when the lower chuck 231 adsorbs the lower wafer W2 and the lower wafer W2 shrinks concentrically, the lower wafer W2 has a diameter approximately equal to that of the upper wafer W1. The multiple elements 42b that adjust the temperature of the lower wafer W2 are controlled, for example, as follows. The elements 42b of the two groups Ga and Gb generate heat and locally heat the lower wafer W2. The elements 42b of the group Gc do not need to generate or absorb heat.

The grouping method and the selection of heat absorption and heat generation are appropriately changed depending on at least one of the warpage of the upper wafer W1 and the lower wafer W2 before bonding and the distortion that occurs between the upper wafer W1 and the lower wafer W2 after bonding.

The warpage of each of the upper wafer W1 and the lower wafer W2 is measured, for example, by a warpage measuring device 5 shown in FIG. 1. The warpage may be measured by 100% inspection or by sampling inspection. For example, if the lower wafer W2 has the same stacked structure, the warpage of the lower wafer W2 is likely to be the same. Therefore, sampling inspection is sufficient for measuring the warpage.

In this embodiment, the warpage of the lower wafer W2 is measured when the temperature distribution of the lower wafer W2 is uniform, but it may be measured when the temperature distribution is non-uniform. Even if the temperature distribution during warpage measurement is non-uniform, if the temperature distribution is known, it is possible to correct the temperature distribution before bonding. The warpage of the upper wafer W1 is measured in the same manner.

The warpage measuring device 5 is, for example, a non-contact three-dimensional measuring machine, and transmits the measured data to the control device 90. The control device 90 controls the first temperature adjustment device 42 or the second temperature adjustment device 43 based on the measured data of the warpage measuring device 5. The warpage measuring device 5 is provided separately from the bonding device 1 in FIG. 1, but may be provided as part of the bonding device 1.

The warpage of the lower wafer W2 can also be measured by the first camera S1 or the first displacement meter S3 shown in FIG. 11. These sensors S1 and S3 can measure the distance to each measurement point on the bonding surface W2j of the lower wafer W2. The measurement is performed, for example, by placing the lower wafer W2 slidably on three holding pins 265 and floating the lower wafer W2 above the lower chuck 231. At that time, the three holding pins 265 do not adsorb the lower wafer W2.

For example, while the moving mechanism 290 moves the lower chuck 231 horizontally, the control device 90 repeatedly adjusts the focal length of the first camera S1 so that the focus of the first camera S1 is on the bonding surface W2j of the lower wafer W2. Based on the change in the focal length of the first camera S1, the control device 90 can measure the height distribution of the bonding surface W2j and measure the warpage of the bonding surface W2j.

Alternatively, the first displacement meter S3 repeatedly measures the height of the bonding surface W2j of the lower wafer W2 while the moving mechanism 290 moves the lower chuck 231 in the horizontal direction. The control device 90 can measure the height distribution of the bonding surface W2j using the first displacement meter S3, and can measure the warpage of the bonding surface W2j.

The warpage of the lower wafer W2 can also be measured based on the distribution of the suction pressure of the lower wafer W2 by the lower chuck 231. The smaller the warpage of the lower wafer W2, the smaller the gap between the lower wafer W2 and the lower chuck 231, and the higher the adhesion, the larger the magnitude (absolute value) of the negative pressure, which is the suction pressure.

For example, if the warp of the lower wafer W2 is as shown in FIG. 15(A), the distribution of the suction pressure of the lower wafer W2 will be as shown in FIG. 15(B). The numerical values of the negative pressure (unit: kPa) shown in FIG. 15(B) are an example. The larger the gap between the lower wafer W2 and the lower chuck 231, the smaller the magnitude (absolute value) of the negative pressure.

The control device 90 can therefore measure the warpage of the lower wafer W2 based on the distribution of the suction pressure of the lower wafer W2 by the lower chuck 231. The magnitude of the suction pressure is measured by a pressure sensor (not shown).

Similarly, the warpage of the upper wafer W1 can also be measured by the second camera S2 or the second displacement meter S4. These sensors S2 and S4 can measure the distance to each measurement point on the bonding surface W1j of the upper wafer W1. The measurement is performed, for example, by suctioning only the center of the upper wafer W1 and suspending the upper wafer W1 below the upper chuck 230. It is preferable that the three holding pins 265 (or ring-shaped suction pads) suction as close to the center of the upper wafer W1 as possible. The warpage of the upper wafer W1 can also be measured based on the distribution of the suction pressure of the upper wafer W1 by the upper chuck 230.

The distortion that occurs after bonding is measured by a distortion measuring device 6 shown in FIG. 1. The distortion measurement may be a full inspection or a random inspection. For example, if the stacked structure of the lower wafer W2 is the same, the warpage of the lower wafer W2 is likely to be the same, and as a result, the distortion that occurs after bonding is likely to be the same. Therefore, random inspection is sufficient for measuring the distortion.

The distortion measuring device 6 is, for example, a PWG (Patterned Wafer Geometry) patterned wafer flatness measuring device (product name: WaferSight) manufactured by KLA-Tencor Corporation, and transmits the measured data to the control device 90. The control device 90 controls the first temperature adjustment device 42 or the second temperature adjustment device 43 based on the measured data of the distortion measuring device 6. Although the distortion measuring device 6 is provided separately from the bonding device 1 in FIG. 1, it may be provided as part of the bonding device 1.

Although the embodiments of the joining device and joining method according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. Naturally, these also fall within the technical scope of the present disclosure.

1 Bonding device 90 Control device (control unit)
230 Upper chuck (first holding part)
231 Lower chuck (second holding portion)
250 Pushing part W1 Upper wafer (first substrate)
W2 Lower wafer (second substrate)
T Polymer Substrate

Claims (12)

A bonding apparatus that bonds a bonding surface of a first substrate and a bonding surface of a second substrate to each other so as to face each other, thereby producing a laminated substrate including the first substrate and the second substrate, comprising:
a first holding portion that holds the first substrate from above;
a second holding portion that holds the second substrate from below;
a pressing portion that presses down a center of the first substrate, the center being spaced apart from the second substrate, to bring the first substrate into contact with the second substrate;
a temperature adjusting unit that adjusts a temperature distribution of the first substrate or the second substrate before bonding;
a control unit that controls the temperature adjustment unit based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding apparatus comprising: a measuring unit that measures warpage of the first substrate or the second substrate before bonding . The bonding apparatus according to claim 1 , wherein the measurement unit includes a sensor that measures a distance to each measurement point on the bonding surface of the first substrate or the second substrate. The joining apparatus according to claim 2 , wherein the sensor of the measuring unit includes a camera or a displacement meter. A bonding apparatus that bonds a bonding surface of a first substrate and a bonding surface of a second substrate to each other so as to face each other, thereby producing a laminated substrate including the first substrate and the second substrate, comprising:
a first holding portion that holds the first substrate from above;
a second holding portion that holds the second substrate from below;
a pressing portion that presses down a center of the first substrate, the center being spaced apart from the second substrate, to bring the first substrate into contact with the second substrate;
a temperature adjusting unit that adjusts a temperature distribution of the first substrate or the second substrate before bonding;
a control unit that controls the temperature adjustment unit based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding apparatus, wherein when the first substrate or the second substrate has an axisymmetric warp before bonding, the control unit controls the temperature adjustment unit to control the temperature distribution of the first substrate or the second substrate to an axisymmetric distribution . A bonding apparatus that bonds a bonding surface of a first substrate and a bonding surface of a second substrate to each other so as to face each other, thereby producing a laminated substrate including the first substrate and the second substrate, comprising:
a first holding portion that holds the first substrate from above;
a second holding portion that holds the second substrate from below;
a pressing portion that presses down a center of the first substrate, the center being spaced apart from the second substrate, to bring the first substrate into contact with the second substrate;
a temperature adjusting unit that adjusts a temperature distribution of the first substrate or the second substrate before bonding;
a control unit that controls the temperature adjustment unit based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding apparatus, wherein when the first substrate or the second substrate has a concentric warp before bonding, the control unit controls the temperature adjustment unit to control the temperature distribution of the first substrate or the second substrate to a concentric distribution . A bonding apparatus that bonds a bonding surface of a first substrate and a bonding surface of a second substrate to each other so as to face each other, thereby producing a laminated substrate including the first substrate and the second substrate, comprising:
a first holding portion that holds the first substrate from above;
a second holding portion that holds the second substrate from below;
a pressing portion that presses down a center of the first substrate, the center being spaced apart from the second substrate, to bring the first substrate into contact with the second substrate;
a temperature adjusting unit that adjusts a temperature distribution of the first substrate or the second substrate before bonding;
a control unit that controls the temperature adjustment unit based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding apparatus, wherein, when the distortion occurring between the first substrate and the second substrate after bonding is axisymmetric, the control unit controls the temperature adjustment unit to control the temperature distribution of the first substrate or the second substrate to an axisymmetric distribution . A bonding apparatus that bonds a bonding surface of a first substrate and a bonding surface of a second substrate to each other so as to face each other, thereby producing a laminated substrate including the first substrate and the second substrate, comprising:
a first holding portion that holds the first substrate from above;
a second holding portion that holds the second substrate from below;
a pressing portion that presses down a center of the first substrate, the center being spaced apart from the second substrate, to bring the first substrate into contact with the second substrate;
a temperature adjusting unit that adjusts a temperature distribution of the first substrate or the second substrate before bonding;
a control unit that controls the temperature adjustment unit based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding apparatus, wherein, when the distortion occurring between the first substrate and the second substrate after bonding is concentric, the control unit controls the temperature adjustment unit to control the temperature distribution of the first substrate or the second substrate to a concentric distribution . the temperature adjustment unit includes a plurality of elements that locally heat or cool the first substrate or the second substrate,
The plurality of elements are arranged in a plane,
The bonding apparatus according to claim 1 , wherein the control unit controls the plurality of elements individually. A bonding method comprising: placing a bonding surface of a first substrate and a bonding surface of a second substrate facing each other; pressing down a center of the first substrate, the center being disposed above the second substrate at a distance from the second substrate, to contact the second substrate; and bringing an entire bonding surface of the first substrate into contact with an entire bonding surface of the second substrate, thereby manufacturing a laminated substrate including the first substrate and the second substrate,
adjusting a temperature distribution of the first substrate or the second substrate before bonding based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding method , in which, when the first substrate or the second substrate has an axisymmetric warp before bonding, a temperature distribution of the first substrate or the second substrate before bonding is controlled to an axisymmetric distribution . A bonding method comprising: placing a bonding surface of a first substrate and a bonding surface of a second substrate facing each other; pressing down a center of the first substrate, the center being disposed above the second substrate at a distance from the second substrate, to contact the second substrate; and bringing an entire bonding surface of the first substrate into contact with an entire bonding surface of the second substrate, thereby manufacturing a laminated substrate including the first substrate and the second substrate,
adjusting a temperature distribution of the first substrate or the second substrate before bonding based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding method , in which, when the first substrate or the second substrate has a concentric warp before bonding, a temperature distribution of the first substrate or the second substrate before bonding is controlled to a concentric distribution. A bonding method comprising: placing a bonding surface of a first substrate and a bonding surface of a second substrate facing each other; pressing down a center of the first substrate, the center being disposed above the second substrate at a distance from the second substrate, to contact the second substrate; and bringing an entire bonding surface of the first substrate into contact with an entire bonding surface of the second substrate, thereby manufacturing a laminated substrate including the first substrate and the second substrate,
adjusting a temperature distribution of the first substrate or the second substrate before bonding based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding method , in which, when a distortion occurring between the first substrate and the second substrate after bonding is axisymmetric, a temperature distribution of the first substrate or the second substrate before bonding is controlled to be an axisymmetric distribution. A bonding method comprising: placing a bonding surface of a first substrate and a bonding surface of a second substrate facing each other; pressing down a center of the first substrate, the center being disposed above the second substrate at a distance from the second substrate, to contact the second substrate; and bringing an entire bonding surface of the first substrate into contact with an entire bonding surface of the second substrate, thereby manufacturing a laminated substrate including the first substrate and the second substrate,
adjusting a temperature distribution of the first substrate or the second substrate before bonding based on at least one of warping of the first substrate and the second substrate before bonding and distortion occurring between the first substrate and the second substrate after bonding ;
A bonding method , in which, when a distortion occurring between the first substrate and the second substrate after bonding is concentric, a temperature distribution of the first substrate or the second substrate before bonding is controlled to a concentric distribution.

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