JP6882755B2 - Wafer bonding method and substrate bonding equipment - Google Patents

Description

The present invention relates to a substrate bonding method and a substrate bonding device.

After measuring the amount of misalignment of both objects while holding one of the two objects on the stage and the other on the head, and aligning the objects based on the amount of misalignment. , A joining device for joining objects to be joined has been proposed (see, for example, Patent Document 1).

JP-A-2009-216985

By the way, vibration may occur in the joining device depending on the installation location of the joining device. In this case, in the joining device described in Patent Document 1, the head vibrates relative to the stage, and there is a possibility that the relative misalignment amount of both objects to be joined cannot be measured accurately. If the measurement accuracy of the amount of misalignment between the two objects to be joined is low, it becomes difficult to join the two objects to be joined with high positional accuracy.

The present invention has been made in view of the above reasons, and an object of the present invention is to provide a substrate bonding method and a substrate bonding device capable of bonding substrates to each other with high position accuracy.

In order to achieve the above object, the substrate bonding method according to the present invention is
This is a substrate bonding method for joining a first substrate provided with a first alignment mark and a second substrate provided with a second alignment mark.
A plurality of times repeatedly to measurement step to measure a relative positional deviation amount with respect to the second substrate of the first substrate from the relative positional deviation amount with respect to the second alignment mark of the first alignment mark,
A first representative value calculation step of calculating a first representative value of a plurality of relative positional deviation amount obtained by repeat several times to measure the relative positional deviation amount,
A position adjusting step of adjusting the relative position of the first substrate with respect to the second substrate so that the first representative value becomes smaller, and
When the first representative value is equal to or less than a preset displacement amount threshold value, a contact step of bringing the bonding surface of the first substrate with the second substrate into contact with the bonding surface of the second substrate with the first substrate. And, including.

The substrate bonding method according to the present invention from another viewpoint is
A substrate bonding method for bonding a first substrate and a second substrate vibrating with respect to the first substrate.
A contact step in which the joint surface of the first substrate with the second substrate is brought into contact with the joint surface of the second substrate with the first substrate.
A measurement step of measuring the amount of misalignment of the first substrate with respect to the second substrate in a state where the joint surface of the first substrate is in contact with the joint surface of the second substrate.
A joining step of joining the joining surface of the first substrate with the second substrate to the joining surface of the second substrate with the first substrate.
A detachment step of separating the joint surface of the first substrate from the joint surface of the second substrate, and
A second representative value calculation step for calculating a second representative value of a plurality of misalignment amounts obtained by repeatedly executing the contact step, the measurement step, and the detachment step a plurality of times.
A position adjusting step of adjusting the relative position of the first substrate with respect to the second substrate so that the second representative value becomes smaller in a state where the bonding surface of the first substrate and the bonding surface of the second substrate are separated from each other. And, including
If the previous SL positional deviation amount is greater than a preset positional deviation amount threshold, the higher withdrawal Engineering, pre Symbol repeatedly contacting step and the measurement step executed, if the positional displacement amount is less than the positional deviation amount threshold If the misalignment amount is larger than the misalignment amount threshold even after the joining step is performed and the detaching step, the contacting step, and the measuring step are repeatedly executed a plurality of preset times , the second The representative value calculation step and the position adjustment step are performed.

The wafer bonding apparatus according to the present invention from another point of view
A substrate bonding device that joins a first substrate provided with a first alignment mark and a second substrate provided with a second alignment mark.
A first support base that supports the first substrate and
A second support base that is arranged to face the first support base and supports the second substrate on the side facing the first support base.
At least one of the first support and the second support is separated from the first support and the second support in the first direction in which the first support and the second support are close to each other, or the first support and the second support are separated from each other. A support base drive unit that moves in the second direction,
Amount of relative misalignment of the first alignment mark with respect to the second alignment mark The amount of misalignment of the first substrate with respect to the second substrate in a direction orthogonal to the first direction and the second direction. And the measuring unit to measure
The measuring unit is the relative positional deviation amount a plurality of times repeatedly to a plurality of relative positional deviation amount first the so representative value is smaller the first substrate of the second obtained by measuring A position adjusting unit that adjusts relative positions in the first direction and the direction orthogonal to the second direction with respect to the substrate.
It includes a control unit that controls the operation of each of the support base drive unit, the measurement unit, and the position adjustment unit, and calculates the first representative value.

The wafer bonding apparatus according to the present invention from another point of view
A substrate bonding device that joins a first substrate and a second substrate.
A first support base that supports the first substrate and
A second support base that is arranged to face the first support base and supports the second substrate on the side facing the first support base.
At least one of the first support and the second support is separated from the first support and the second support in the first direction in which the first support and the second support are close to each other, or the first support and the second support are separated from each other. A support base drive unit that moves in the second direction,
In a state where the support base driving unit moves at least one of the first support base and the second support base in the first direction so that the first substrate and the second substrate are in contact with each other, the first A measuring unit that measures the amount of misalignment between the first substrate and the second substrate in the direction and the direction orthogonal to the second direction.
A position adjustment unit for adjusting the relative position in a direction perpendicular to the first direction and the second direction with respect to the second substrate before Symbol first substrate,
The support base drive unit, which controls the measuring section and the position adjusting section each operation, e Bei a control unit for calculating a second representative value of the plurality of positional displacement amounts, and
The control unit controls the support base drive unit, the measurement unit, and the position adjustment unit, and when the position shift amount is larger than a preset position shift amount threshold, the support base drive unit is the first. A detaching step in which the first substrate is separated from the second substrate by moving at least one of the 1 support and the second support in the second direction, and the support drive unit is the first support. The contact step of bringing the first substrate into contact with the second substrate by moving at least one of the first substrate and the second support base in the first direction, and the measuring unit is the first substrate and the second substrate. The measurement step of measuring the amount of misalignment in contact with and is repeatedly executed.
When the misalignment amount is equal to or less than the misalignment amount threshold value, a joining step of joining the first substrate to the second substrate is performed.
If the misalignment amount is larger than the misalignment amount threshold even after the detachment step, the contact step, and the measurement step are repeatedly executed a plurality of preset times, the disengagement step, the contact step, and the measurement are performed. A second representative value calculation step for calculating the second representative value of a plurality of misalignment amounts obtained by repeatedly executing the step a plurality of times, and a position adjusting unit so that the second representative value becomes smaller. A position adjusting step of adjusting the relative positions of the first substrate with respect to the second substrate in the first direction and the direction orthogonal to the second direction is performed .

For example, when the second substrate vibrates with respect to the first substrate, the amount of misalignment obtained by measuring the amount of misalignment of the first substrate with respect to the second substrate may vary depending on the timing of measurement. Therefore, for example, when the measurement of the amount of misalignment of the first substrate with respect to the second substrate is performed only once and the relative position of the first substrate with respect to the second substrate is adjusted based on the amount of misalignment obtained by the measurement, the misalignment is performed. The effect of the amount of misalignment due to the timing of quantity measurement is likely to occur. On the other hand, according to the present invention, the substrate bonding apparatus measures the amount of misalignment of the first substrate with respect to the second substrate a plurality of times by the measuring unit in a state where the first substrate and the second substrate are in contact with each other. Execute repeatedly. Then, in the wafer bonding apparatus, the representative value of the plurality of misalignments obtained by repeatedly executing the measurement of the misalignment amount of the first substrate with respect to the second substrate a plurality of times by the position adjusting unit is reduced. Adjust the relative position of the first substrate with respect to the second substrate. As a result, even when the second substrate vibrates with respect to the first substrate, the influence of the error of the displacement amount due to the measurement timing of the displacement amount is reduced, so that the substrates are joined with high positional accuracy. can do.

It is a schematic block diagram of the substrate bonding system which concerns on Embodiment 1 of this invention. (A) is a schematic front view of the external alignment device according to the first embodiment, and (B) is a schematic front view of the joint surface processing device. It is a schematic front view of the inside of the wafer bonding apparatus which concerns on Embodiment 1. FIG. (A) is a schematic front view showing the configuration of the holding mechanism provided on the stage according to the first embodiment, and (B) is a schematic cross-sectional view showing the configuration of the stage and the head according to the first embodiment. (A) is a schematic perspective view showing the vicinity of the stage and the head according to the first embodiment, and (B) is a diagram for explaining a method of finely adjusting the head. (A) is a diagram showing two alignment marks provided on one of the two substrates to be joined, and (B) is a diagram showing two alignment marks provided on the other of the two substrates to be joined. (A) is a schematic view showing a photographed image of an alignment mark, and (B) is a schematic view showing a state in which the alignment marks are displaced from each other. It is a block diagram which shows the structure of the control part which concerns on Embodiment 1. FIG. It is a flowchart which shows the flow of the wafer bonding process which the wafer bonding apparatus which concerns on Embodiment 1 executes. It is a figure for demonstrating the process which the substrate bonding apparatus which concerns on Embodiment 1 calculates the distance between two substrates. (A) is a schematic cross-sectional view showing a state in which the substrate is held by the stage and the head according to the first embodiment, and (B) is a schematic cross-sectional view showing a state in which the stage and the head according to the first embodiment are brought close to each other. Is. It is a flowchart which shows the flow of the position shift amount calculation process executed by the wafer bonding apparatus which concerns on Embodiment 1. FIG. (A) is a diagram showing a state in which the substrate bonding apparatus according to the first embodiment is in contact with the central portions of the two substrates, and (B) is a diagram showing a state in which the substrate bonding apparatus according to the first embodiment is in contact with one substrate. It is a figure which shows the state of being detached from the other substrate. (A) is a diagram showing a state in which one substrate is separated from the other substrate by the substrate bonding apparatus according to the first embodiment, and (B) is a diagram in which the substrate bonding apparatus according to the first embodiment has two substrates. It is a figure which shows the state which joined. (A) is a schematic cross-sectional view showing how the head according to the first embodiment vibrates with respect to the stage, and (B) is a relative of two substrates when the head vibrates with respect to the stage. It is a figure which shows the time-dependent change of the target displacement amount. It is a flowchart which shows the flow of the wafer bonding process which the wafer bonding apparatus which concerns on Embodiment 2 of this invention executes. (A) is a schematic cross-sectional view showing a state in which the substrate bonding apparatus according to the third embodiment of the present invention is close to the stage and the head, and (B) is a schematic cross-sectional view showing a state in which the substrate bonding apparatus according to the third embodiment is close to each other. It is a figure which shows the state which was in contact with each other. It is a flowchart which shows the flow of the wafer bonding process which the wafer bonding apparatus which concerns on Embodiment 3 executes.

Hereinafter, the wafer bonding apparatus according to each embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
In the substrate bonding apparatus according to the present embodiment, the bonding surfaces of two substrates are activated and hydrophilized in a chamber under reduced pressure, and then the substrates are brought into contact with each other to be pressurized and heated. It is a device that joins two substrates. In the activation treatment, the joint surface of the substrate is activated by applying specific particles to the joint surface of the substrate. Further, in the hydrophilic treatment, the joint surface of the substrate is made hydrophilic by supplying water or the like to the vicinity of the joint surface of the substrate activated by the activation treatment.

As shown in FIG. 1, the wafer bonding system according to the present embodiment includes an introduction port 961, an extraction port 962, a first transfer device 930, a cleaning device 940, an external alignment device 800, and a reversing device 950. A bonding surface processing device 600, a substrate bonding device 100, a second transfer device 920, a control unit 700, and a load lock chamber 910 are provided. HEPA (High Efficiency Particulate Air) filters (not shown) are installed in the first transport device 930, the cleaning device 940, and the external alignment device 800, and the inside of them becomes a clean atmospheric pressure environment. There is. On the other hand, the inside of the reversing device 950, the inside of the bonding surface processing device 600, and the inside of the substrate bonding device 100 are set to a vacuum atmosphere. The control unit 700 controls the first transfer device 930, the cleaning device 940, the external alignment device 800, the reversing device 950, the joint surface treatment device 600, the substrate bonding device 100, and the second transfer device 920. The two substrates 301 and 302 joined to each other are first arranged at the introduction port 961. Next, the substrates 301 and 302 are transported from the introduction port 961 to the cleaning device 940 by the atmospheric transfer robot 931 of the first transfer device 930, and the cleaning device 940 performs cleaning to remove foreign substances existing on the substrates 301 and 302. Will be done. Subsequently, the substrates 301 and 302 are transported from the cleaning device 940 to the external alignment device 800 by the transfer robot 931, and the external alignment device 800 measures the substrate thickness together with the alignment of their external shapes. After that, the substrates 301 and 302 are conveyed into the load lock chamber 910 opened to the atmosphere by the atmospheric transfer robot 931. Then, when the degree of vacuum in the load lock chamber 910 becomes the same as the degree of vacuum in the second transfer device 920 due to the discharge of the gas existing in the load lock chamber 910, the substrates 301 and 302 are subjected to the second transfer device. By 920, it is conveyed to the bonding surface processing device 600 and the substrate bonding device 100. Here, the substrate 302 is conveyed to the inverting device 950, inverted on the front and back sides of the inverting device 950, and then conveyed to the substrate bonding device 100. The substrates 301 and 302 are subjected to activation treatment and hydrophilic treatment of their joint surfaces in the joint surface treatment device 600. After that, the substrates 301 and 302 are bonded to each other in the substrate bonding device 100. The second transfer device 920 has a vacuum transfer robot 921, and the vacuum transfer robot 921 transfers the substrates 301 and 302 from the load lock chamber 910 to the joint surface treatment device 600, and from the joint surface treatment device 600 to the reversing device 950 or the substrate bonding device. Transport to 100. The substrates 301 and 302 bonded to each other in the substrate bonding device 100 are transported to the load lock chamber 910 again by the vacuum transfer robot 921. After that, when the load lock chamber 910 is opened to the atmosphere, the substrates 301 and 302 joined to each other are conveyed from the load lock chamber 910 to the take-out port 962 by the atmospheric transfer robot 931.

As shown in FIG. 2A, the external alignment device 800 includes an edge recognition sensor 810, a substrate thickness measuring unit 802, and a stage 803. The stage 803 is rotatable around a central axis orthogonal to the mounting surface on which the substrates 301 and 302 are mounted. The edge recognition sensor 810 recognizes the edges of the substrates 301 and 302 using a laser. The substrate thickness measuring unit 802 is composed of a laser displacement meter, and measures the thickness of the substrates 301 and 302 without contacting the substrates 301 and 302. The external alignment device 800 recognizes the edges of the substrates 301 and 302 by the edge recognition sensor 810 while rotating the substrates 301 and 302 by rotating the stage 803 (see the arrow AR11 in FIG. 2A), and also recognizes the edges of the substrates 301 and 302. The thickness measuring unit 802 measures the thicknesses of the substrates 301 and 302.

As shown in FIG. 2B, the joint surface treatment device 600 includes a chamber 601, an activation treatment unit 610, a hydrophilization treatment unit 620, and a stage 603 on which the substrates 301 and 302 are placed. .. The chamber 601 is connected to the vacuum pump 201 via an exhaust pipe 202B and an exhaust valve 203B. When the exhaust valve 203B is opened and the vacuum pump 201 is operated, the gas in the chamber 601 is discharged to the outside of the chamber 601 through the exhaust pipe 202B, and the air pressure in the chamber 601 is reduced (decompressed). The activation processing unit 610 includes a plasma generation source 611, a trap plate 612, and a bias power supply 613. The activation processing unit 610 has a configuration in which only radicals that have passed through the trap plate 612 when plasma is generated at the plasma generation source 611 are downflowed to the stage 603. If the plasma generation source 611 is an ICP (Inductively Coupled Plasma) device, ions are trapped by the coil, so that a trap plate may not be provided. Further, the bias power supply 613 applies an alternating voltage to the substrates 301 and 302 mounted on the stage 603 to attract ions having kinetic energy near the junction surface of the substrates 301 and 302, and the ions are repeated by the alternating electric field. A sheath region that collides with the substrates 301 and 302 is generated. Then, the joint surfaces of the substrates 301 and 302 are ion-etched by ions having kinetic energy generated in the vicinity of the joint surfaces of the substrates 301 and 302 by the bias power supply 613, and then the joint surfaces are subjected to radical treatment to perform those joint surfaces. It is possible to efficiently generate OH groups.

The hydrophilization treatment unit 620 hydrophilizes the joint surfaces of the substrates 301 and 302 by adhering water or an OH-containing substance to the joint surfaces of the substrates 301 and 302 activated by the activation treatment unit 610. The hydrophilization treatment unit 620 executes the hydrophilization treatment by supplying water (H2O) around the joint surfaces of the substrates 301 and 302 in the chamber 601. The hydrophilization treatment unit 620 includes a steam generator 621, a supply valve 622, and a supply pipe 623. The steam generator 621 generates steam by bubbling the stored water with a carrier gas such as argon (Ar), nitrogen (N2), helium (He), or oxygen (O2). The flow rates of water vapor and carrier gas are adjusted by controlling the opening degree of the supply valve 622.

As shown in FIG. 3, the substrate bonding device 100 is positioned with the chamber 200, the stage (first support base) 401, the head (second support base) 402, the stage drive unit 403, the head drive unit 404, and the substrate heating unit 420. It is provided with a measuring unit 500. Further, the wafer bonding device 100 includes a distance measuring unit (not shown) for measuring the distance between the stage 401 and the head 402. In the following description, the ± Z direction of FIG. 3 will be described as the vertical direction and the XY direction will be described as the horizontal direction.

The chamber 200 is connected to the vacuum pump 201 via an exhaust pipe 202C and an exhaust valve 203C. When the exhaust valve 203C is opened and the vacuum pump 201 is operated, the gas in the chamber 200 is discharged to the outside of the chamber 200 through the exhaust pipe 202C, and the air pressure in the chamber 200 is reduced (decompressed). Further, the air pressure (vacuum degree) in the chamber 200 can be adjusted by adjusting the exhaust amount by changing the opening / closing amount of the exhaust valve 203C. Further, a part of the chamber 200 is provided with a window portion 503 used for measuring a relative position between the substrates 301 and 302 by the position measuring portion 500.

The stage 401 and the head 402 are arranged in the chamber 200 so as to face each other in the vertical direction. The stage 401 supports the substrate 301 on its upper surface, and the head 402 supports the substrate 302 on its lower surface. The upper surface of the stage 401 and the lower surface of the head 402 are roughened in consideration of the case where the contact surfaces of the substrates 301 and 302 with the stage 401 and the head 402 are mirror surfaces and are not easily peeled off from the stage 401 and the head 402. It may have been done. As shown in FIG. 4A, the stage 401 and the head 402 have a holding mechanism 440 for holding the substrates 301 and 302, a first pressing mechanism 431 for pressing the central portion of the substrate 301, and a central portion of the substrate 302. It has a second pressing mechanism 432 for pressing. The holding mechanism 440 is composed of a vacuum chuck having a plurality of (four in FIG. 4A) annular suction portions 440a, 440b, 440c, and 440d. The substrates 301 and 302 are held by the stage 401 and the head 402 in a state of being sucked by the suction portions 440a, 440b, 440c and 440d provided on the stage 401 and the head 402.

The suction portions 440a, 440b, 440c, and 440d can take a state in which the substrates 301 and 302 are separately sucked and a state in which the substrates 301 and 302 are not sucked. For example, the suction portions 440a and 440b arranged relatively inside the stage 401 and the head 402 are not vacuum-sucked, and the suction portions 440c and 440d arranged relatively outside the stage 401 and the head 402 are vacuum-sucked. Can be in a state of being. Further, the radius L1 of the suction part 440a located closest to the center of the stage 401 and the head 402, the distance L2 between the suction part 440a and the suction part 440a and the suction part 440b adjacent to the outside, the suction part 440b and the suction part The fixed positions of the substrates 301 and 302 are determined by the distance L3 between the 440b and the adjacent suction portion 440c on the outside and the distance L4 between the suction portion 440c and the suction portion 440d located on the outermost side.

As shown in FIG. 4B, the first pressing mechanism 431 is provided in the central portion of the stage 401, and the second pressing mechanism 432 is provided in the central portion of the head 402. The first pressing mechanism 431 has a first pressing portion 431a that can appear and disappear toward the head 402 side, and a first pressing driving portion 431b that drives the first pressing portion 431a. The second pressing mechanism 432 has a second pressing portion 432a that can appear and disappear toward the stage 401 side, and a second pressing driving portion 432b that drives the second pressing portion 432a. The first pressing unit 431b and the second pressing drive unit 432b include, for example, the first pressing unit 431a and the first pressing unit 431a by controlling the air pressure in the cylinder into which a part of the second pressing unit 432a is fitted. A configuration for driving the second pressing portion 432a can be adopted. Alternatively, a voice coil motor may be adopted as the first pressing drive unit 431b and the second pressing drive unit 432b. The crown portions of the first pressing portion 431a and the second pressing portion 432a that come into contact with the substrates 301 and 302 have a dome-shaped shape. Further, the first pressing portion 431a and the second pressing portion 432a control the pressure to keep the pressure applied to the substrates 301 and 302 constant, and control to keep the contact positions of the substrates 301 and 302 constant. Either of the position control is performed. For example, the position of the first pressing portion 431a is controlled and the pressure of the second pressing portion 432a is controlled, so that the substrates 301 and 302 are pressed at a constant position with a constant pressure.

The substrate heating unit 420 is composed of heaters 421 and 422. The heaters 421 and 422 are composed of, for example, electric heaters. The heaters 421 and 422 heat the substrates 301 and 302 by transferring heat to the substrates 301 and 302 supported by the stage 401 and the head 402. Further, by adjusting the calorific value of the heaters 421 and 422, the temperature of the substrates 301 and 302 and their joint surfaces can be adjusted.

The stage drive unit 403 can move the stage 401 in the XY direction or rotate it around the Z axis.

The head drive unit 404 uses an elevating drive unit (support base drive unit) 406 for raising and lowering the head 402 in the upward (second direction) or downward direction (first direction) (see arrow AR1 in FIG. 3) and the head 402. It has an XY direction drive unit 405 that moves in the XY direction, and a rotation drive unit 407 that rotates the head 402 in the rotation direction around the Z axis (see arrow AR2 in FIG. 3). The XY direction drive unit 405 and the rotation drive unit 407 form a position adjustment unit that adjusts the relative position of the substrate 301 in the direction orthogonal to the vertical direction (XY direction, rotation direction around the Z axis) with respect to the substrate 302. Further, the head drive unit 404 includes a piezo actuator 411 for adjusting the inclination of the head 402 with respect to the stage 401, and a second pressure sensor 412 for measuring the pressure applied to the head 402. The substrate 301 held by the stage 401 by the XY direction drive unit 405 and the rotation drive unit 407 moving the head 402 relative to the stage 401 in the X direction, the Y direction, and the rotation direction around the Z axis. Can be aligned with the substrate 302 held by the head 402.

The elevating drive unit 406 moves the head 402 downward to bring the stage 401 and the head 402 closer to each other. Further, the elevating drive unit 406 separates the stage 401 and the head 402 by moving the head 402 upward. When the elevating drive unit 406 moves the head 402 downward, the substrate 301 held by the stage 401 and the substrate 302 held by the head 402 come into contact with each other. Then, when the elevating drive unit 406 exerts a driving force on the head 402 in the direction approaching the stage 401 in a state where the boards 301 and 302 are in contact with each other, the board 302 is pressed against the board 301. Further, the elevating drive unit 406 is provided with a first pressure sensor 408 that measures the driving force that the elevating drive unit 406 exerts on the head 402 in the direction approaching the stage 401. From the measured value of the first pressure sensor 408, the pressure acting on the joint surface of the substrates 301 and 302 when the substrate 302 is pressed against the substrate 301 by the elevating drive unit 406 can be detected. The first pressure sensor 408 is composed of, for example, a load cell.

As shown in FIG. 5A, there are three piezo actuators 411 and three second pressure sensors 412, respectively. The three piezo actuators 411 and the three second pressure sensors 412 are arranged between the head 402 and the XY direction drive unit 405. The three piezo actuators 411 are located at three positions on the upper surface of the head 402 that are not on the same straight line, and at three positions that are evenly spaced along the circumferential direction of the head 402 at the peripheral portion of the upper surface of the circular head 402 in a plan view. It is fixed. Each of the three second pressure sensors 412 connects the upper end of the piezo actuator 411 and the lower surface of the XY direction drive unit 405. Each of the three piezo actuators 411 can be expanded and contracted in the vertical direction. Then, by expanding and contracting the three piezo actuators 411, the inclination of the head 402 around the X-axis and the Y-axis and the vertical position of the head 402 are finely adjusted. For example, as shown by the broken line in FIG. 5 (B), when the head 402 is tilted with respect to the stage 401, one of the three piezo actuators 411 is extended (see arrow AR3 in FIG. 5 (B)). By finely adjusting the posture of the head 402, the lower surface of the head 402 and the upper surface of the stage 401 can be made parallel to each other. Further, the three second pressure sensors 412 measure the pressing force at three positions on the lower surface of the head 402. Then, by driving each of the three piezo actuators 411 so that the pressing forces measured by the three second pressure sensors 412 are equal, the substrate 301 keeps the lower surface of the head 402 and the upper surface of the stage 401 parallel to each other. , 302 can be brought into contact with each other.

The distance measuring unit is composed of a laser range finder and measures the distance between the stage 401 and the head 402 without contacting the stage 401 and the head 402. Specifically, for example, when the head 402 is transparent, the distance measuring unit receives the reflected light on the upper surface of the stage 401 and the lower surface of the head 402 when the laser beam is irradiated from above the head 402 toward the stage 401. The distance between the stage 401 and the head 402 is measured from the difference from the reflected light of. As shown in FIG. 4A, the distance measuring unit faces the three portions P11, P12, and P13 on the upper surface of the stage 401 and the portions P11, P12, and P13 on the lower surface of the head 402 in the Z direction. The distance between the parts P21, P22, and P23 of the portion is measured.

Returning to FIG. 3, the position measuring unit (measuring unit) 500 measures the amount of misalignment between the substrate 301 and the substrate 302 in the direction orthogonal to the vertical direction (XY direction, rotation direction around the Z axis). The position measuring unit 500 includes a plurality of (two in FIG. 3) first imaging unit 501, second imaging unit 502, and mirrors 504 and 505. The first image pickup unit 501 and the second image pickup unit 502 each have an image pickup element (not shown) and a coaxial illumination system. As the light source of the coaxial illumination system of the first imaging unit 501 and the second imaging unit 502, light (for example, infrared light) transmitted through the windows 503 provided in the substrates 301, 302, the stage 401, and the chamber 200 is emitted. A light source is used.

For example, as shown in FIGS. 6A and 6B, the substrate 301 is provided with two marks (hereinafter referred to as “alignment marks”) MK1a and MK1b, and the substrate 302 is provided with two alignment marks MK2a. , MK2b is provided. The wafer bonding device 100 recognizes the positions of the alignment marks MK1a, MK1b, MK2a, and MK2b provided on both substrates 301 and 302 by the position measuring unit 500, and aligns the two substrates 301 and 302 (alignment operation). To execute. More specifically, the substrate bonding apparatus 100 first recognizes the alignment marks MK1a, MK1b, MK2a, and MK2b provided on the substrates 301 and 302 by the position measuring unit 500, and performs a rough alignment operation of the substrates 301 and 302. Rough alignment operation) is executed to make the two substrates 301 and 302 face each other. After that, the substrate bonding device 100 simultaneously recognizes the alignment marks MK1a, MK2a, MK1b, and MK2b provided on the two substrates 301 and 302 by the position measuring unit 500 in a state where the two substrates 301 and 302 face each other. Perform a more precise alignment operation (fine alignment operation).

Here, as shown in FIG. 3, the light emitted from the light source (not shown) of the coaxial illumination system of the imaging unit (first imaging unit) 501 is reflected by the mirror 504 and travels upward, and the window portion. It is transparent to a part or all of the 503 and the substrates 301 and 302 (see the dashed arrows SC1 and SC2 in FIG. 3). The light transmitted through a part or all of the substrates 301 and 302 is reflected by the alignment marks MK1a and MK2a of the substrates 301 and 302, travels downward, passes through the window portion 503, is reflected by the mirror 504, and is reflected by the mirror 504 for the first imaging. It is incident on the image sensor of unit 501. Further, the light emitted from the light source (not shown) of the coaxial illumination system of the imaging unit (second imaging unit) 502 is reflected by the mirror 505 and travels upward, and one of the window unit 503 and the substrates 301 and 302. Permeate part or all. The light transmitted through a part or all of the substrates 301 and 302 is reflected by the alignment marks MK1a and MK2a of the substrates 301 and 302, travels downward, passes through the window 503 and is reflected by the mirror 505, and is reflected by the mirror 505 for the second imaging. It is incident on the image sensor of unit 502. In this way, as shown in FIG. 7A, the position measuring unit 500 includes the captured image GAa including the alignment marks MK1a and MK2a of the two substrates 301 and 302, and the alignment marks MK1b of the two substrates 301 and 302. , The photographed image GAb including MK2b is acquired. The shooting operation of the captured image GAa by the first imaging unit 501 and the photographing operation of the captured image GAb by the second imaging unit 502 are executed at the same time.

As shown in FIG. 8, the control unit 700 includes an MPU (Micro Processing Unit) 701, a main storage unit 702, an auxiliary storage unit 703, an interface 704, and a bus 705 connecting each unit. The main storage unit 702 is composed of a volatile memory and is used as a work area of the MPU 701. The auxiliary storage unit 703 is composed of a non-volatile memory and stores a program executed by the MPU 701. In addition, the auxiliary storage unit 703 also stores the position shift amount thresholds Δxth, Δyz, and Δθth that are preset with respect to the relative calculated position shift amounts Δx, Δy, and Δθ of the substrates 301 and 302, which will be described later. Hereinafter, the interface 704 converts the measurement signals input from the first pressure sensor 408, the second pressure sensor 412, the distance measuring unit 801 and the substrate thickness measuring unit 802 and the edge recognition sensor 810 into measurement information and outputs the measurement signals to the bus 705. .. Further, the interface 704 converts the captured image signal input from the first imaging unit 501 and the second imaging unit 502 into captured image information and outputs the captured image information to the bus 705. Further, the MPU 701 reads the program stored in the auxiliary storage unit 703 into the main storage unit 702 and executes it, so that the holding mechanism 440, the piezo actuator 411, the first pressing drive unit 431b, and the second pressing are executed via the interface 704. A control signal is output to each of the drive unit 432b, the substrate heating unit 420, the stage drive unit 403, the head drive unit 404, the activation processing unit 610, the hydrophilization processing unit 620, the vacuum transfer robot 921, and the atmosphere transfer robot 931.

As shown in FIG. 7B, the control unit 700 is positioned between a set of alignment marks MK1a and MK2a provided on the substrates 301 and 302 based on the captured image GAa acquired from the first imaging unit 501. The deviation amounts Δxa and Δya are calculated. Note that FIG. 7B shows a state in which a set of alignment marks MK1a and MK2a are displaced from each other. Similarly, the control unit 700 has a misalignment amount Δxb, Δyb between the other pair of alignment marks MK1b, MK2b provided on the substrates 301, 302 based on the captured image GAb acquired from the second imaging unit 502. Is calculated.

After that, the control unit 700 rotates around the X direction, the Y direction, and the Z axis based on the positional deviation amounts Δxa, Δya, Δxb, and Δyb of these two sets of alignment marks and the geometrical relationship between the two sets of marks. The relative misalignment amounts Δx, Δy, and Δθ of the two substrates 301 and 302 in the direction are calculated. Then, the control unit 700 moves the head 402 in the X and Y directions and rotates it around the Z axis so that the calculated displacement amounts Δx, Δy, and Δθ are reduced. As a result, the relative displacement amounts Δx, Δy, and Δθ of the two substrates 301 and 302 are reduced. In this way, the wafer bonding apparatus 100 executes a fine alignment operation for correcting the displacement amounts Δx, Δy, and Δθ of the two substrates 301 and 302 in the horizontal direction.

Next, the wafer bonding process executed by the wafer bonding device 100 according to the present embodiment will be described with reference to FIGS. 9 to 15. This wafer bonding process is started when the control unit 700 starts a program for executing the wafer bonding process. In FIG. 9, it is assumed that the substrates 301 and 302 are transported into the external alignment device 800 by the first transport device 930. Further, it is assumed that the substrate 302 vibrates with respect to the substrate 301.

First, as shown in FIG. 9, the external alignment device 800 measures the thicknesses t1 and t2 of the substrates 301 and 302, respectively, by the substrate thickness measuring unit 802 (step S1). At this time, the substrate thickness measuring unit 802 measures the thickness of the substrates 301 and 302 at a plurality of locations (for example, three locations). Then, the control unit 700 calculates the average value of the plurality of measured values measured by the substrate thickness measuring unit 802 for each of the substrates 301 and 302 as the thicknesses t1 and t2 (see FIG. 10). Then, the substrates 301 and 302 for which the thickness measurement has been completed are transported from the external alignment device 800 to the load lock chamber 910 by the vacuum transfer robot 921 of the second transfer device 920. Then, when the degree of vacuum in the load lock chamber 910 becomes the same as the degree of vacuum in the second transfer device 920 due to the discharge of the gas existing in the load lock chamber 910, the substrates 301 and 302 are subjected to the second transfer device. By 920, it is conveyed to the joint surface treatment device 600.

Next, in the joint surface treatment device 600, the activation treatment unit 610 executes an activation treatment for activating the joint surfaces of the substrates 301 and 302, and the hydrophilic treatment unit 620 hydrophilizes the joint surfaces of the substrates 301 and 302. (Hydrophilic treatment step) (step S2). Here, first, the activation processing unit 610 activates the joint surfaces of the substrates 301 and 302 by causing ions having kinetic energy to collide with the joint surfaces of the substrates 301 and 302. Then, the hydrophilization treatment unit 620 introduces the steam generated by the steam generator 621 together with the carrier gas into the chamber 200 through the supply pipe 623. As a result, a layer terminated with a hydroxyl group (OH group) is formed on the bonding surface of the substrates 301 and 302.

Subsequently, the substrate bonding device 100 measures the distance between the upper surface of the stage 401 and the lower surface of the head 402 by the distance measuring unit 801 in a state where the substrates 301 and 302 are not held by the stage 401 and the head 402. (Step S3). At this time, as shown in FIG. 5A, the distance measuring unit 801 includes three parts P11, P12, P13 on the upper surface of the stage 401 and corresponding three parts P21, P22, P23 on the lower surface of the head 402. Measure each distance between. Then, the control unit 700 calculates the average value of the three measured values measured by the distance measuring unit 801 as the distance G1 (see FIG. 10).

After that, when the substrates 301 and 302 that have been activated and hydrophilized are transported from the bonding surface treatment device 600 to the substrate bonding device 100 by the vacuum transfer robot 921 of the second transfer device 920, the substrate bonding device 100 Holds the substrates 301 and 302 (step S4). At this time, the substrates 301 and 302 are adsorbed by all of the suction portions 440a, 440b, 440c and 440d provided on the stage 401 and the head 402, as shown by the arrows in FIG. , Held by the head 402. Here, the substrate bonding device 100 executes the above-mentioned rough alignment operation on the substrates 301 and 302.

Next, the substrate bonding device 100 calculates the distance between the substrates 301 and 302 from the distance G1 between the stage 401 and the head 402 and the thicknesses t1 and t2 of the substrates 301 and 302 (step S5). Here, the control unit 700 calculates the distance G2 (see FIG. 10) between the substrates 301 and 302 from the thicknesses t1 and t2 of the substrates 301 and 302 and the distance G1 between the stage 401 and the head 402. ..

Returning to FIG. 9, the substrate bonding apparatus 100 subsequently moves the head 402 downward to bring the substrates 301 and 302 closer to each other (step S6). As shown in FIG. 11B, the wafer bonding device 100 moves the head 402 downward until the distance between the substrates 301 and 302 becomes a distance G11 shorter than the distance G2. This distance G11 is set to a distance at which the substrates 301 and 302 can come into contact with each other by bending the substrates 301 and 302 as described later. The distance G11 is set to, for example, about 30 μm. Further, the wafer bonding device 100 calculates the amount of movement of the head 402 for making the distance between the substrates 301 and 302 the distance G11 from the calculated distance G2 between the substrates 301 and 302, and sets the head 402 by the calculated movement amount. move.

Next, the substrate bonding device 100 repeatedly measures the amount of misalignment of the substrate 301 with respect to the substrate 302 a plurality of times, and repeatedly measures the amount of misalignment a plurality of times to obtain a representative value (first representative value) of the plurality of misalignments. ) Is calculated (first representative value calculation step), and the misalignment amount calculation process is executed (step S7). Here, the position shift amount calculation process executed by the wafer bonding apparatus 100 will be described with reference to FIG.

First, as shown in FIG. 12, the wafer bonding device 100 measures the relative displacement amounts of the substrates 301 and 302 by the position measuring unit 500 (step S101). Here, the control unit 700 first receives images GAa of the two substrates 301 and 302 (see FIG. 11A) in a non-contact state from the first imaging unit 501 and the second imaging unit 502 of the position measuring unit 500. , GAb (see FIG. 6 (A)). Then, the control unit 700 calculates the displacement amounts Δx, Δy, and Δθ of the two substrates 301 and 302 in the X direction, the Y direction, and the rotation direction around the Z axis based on the two captured images GAa and GAb. .. Specifically, the control unit 700 uses the vector correlation method based on the captured images GAa in which the alignment marks MK1a and MK2a separated in the Z direction are simultaneously read, for example, and the displacement amounts Δxa and Δya (see FIG. 7B). ) Is calculated. Similarly, the displacement amounts Δxb and Δyb (see FIG. 7B) are calculated using the vector correlation method based on the captured image GAb in which the alignment marks MK1b and MK2b separated in the Z direction are simultaneously read. Then, the control unit 700 calculates the displacement amounts Δx, Δy, Δθ in the horizontal direction of the two substrates 301 and 302 based on the displacement amounts Δxa, Δya, Δxb, and Δyb.

Returning to FIG. 12, next, the wafer bonding apparatus 100 determines whether or not the measurement of the relative misalignment amount of the substrates 301 and 302 is repeated a preset number of times (step S102). The number of repetitions of the measurement of the amount of misalignment is appropriately set according to the magnitude of the vibration amplitude of the head 402, the vibration cycle, the time required for the measurement, and the like, and is set to, for example, about 5 times. When the substrate bonding apparatus 100 determines that the number of repetitions of the measurement of the relative displacement amount of the substrates 301 and 302 has not reached the preset number of repetitions (step S102: No), the process of step S101 is executed again. To do.

On the other hand, it is assumed that the substrate bonding apparatus 100 determines that the number of repetitions of the measurement of the relative displacement amount of the substrates 301 and 302 has reached the preset number of repetitions (step S102: Yes). In this case, the wafer bonding apparatus 100 uses the representative values (first representative values) of the measured values of the plurality of misalignments obtained by the measurement as the relative misalignments Δx, Δy, and Δθ of the substrates 301 and 302. Calculate (step S103). Here, the wafer bonding device 100 calculates an average value or an intermediate value of the measured values of a plurality of misalignment amounts.

Returning to FIG. 9, the wafer bonding apparatus 100 subsequently sets the substrate 302 relative to the substrate 301 so as to correct the misalignment amounts Δx, Δy, and Δθ calculated by executing the misalignment amount calculation process. Alignment is executed by moving to (step S8). Here, the wafer bonding device 100 moves the head 402 in the X direction, the Y direction, and the rotation direction around the Z axis so that the misalignment amounts Δx, Δy, and Δθ are eliminated while the stage 401 is fixed.

After that, the substrate bonding device 100 bends the substrates 301 and 302 in a state where the substrates 301 and 302 are separated from each other (step S9). As shown in FIG. 13A, for example, the substrate bonding device 100 bends the substrate 301 so that the central portion 301c projects toward the substrate 302 with respect to the peripheral portion 301s of the bonding surface of the substrate 301. At this time, the substrate bonding device 100 sucks the substrate 301 by the two suction portions 440c and 440d on the peripheral side of the stage 401, and sucks the substrate 301 by the two suction portions 440a and 440b on the central portion side of the stage 401. Stop (see the arrow in FIG. 13 (A)). At this time, the substrate bonding device 100 attaches the substrates 301 and 302 to the stage 401 and the head 402 at two suction positions (holding positions) at different distances from the central portions of the substrates 301 and 302 at the peripheral portions of the substrates 301 and 302. I'm holding it. Then, the substrate bonding device 100 presses the central portion of the substrate 301 toward the substrate 302 by the first pressing portion 431a in a state where the peripheral portion 301s of the substrate 301 is attracted (held) to the stage 401. As a result, the substrate 301 bends so that the central portion 301c of the joint surface protrudes toward the substrate 302. Further, as shown in FIG. 13A, for example, the substrate bonding device 100 bends the substrate 302 so that the central portion 302c projects toward the substrate 301 with respect to the peripheral portion 302s of the bonding surface of the substrate 302. At this time, the substrate bonding device 100 sucks the substrate 302 by the two suction portions 440c and 440d on the peripheral side of the head 402, and sucks the substrate 302 by the two suction portions 440a and 440b on the central portion side of the head 402. Stop (see the arrow in FIG. 13 (A)). Then, the substrate bonding device 100 presses the central portion of the substrate 302 toward the substrate 301 by the second pressing portion 432a in a state where the peripheral portion 302s of the substrate 302 is attracted (held) to the head 402. As a result, the substrate 302 bends so that the central portion 302c of the joint surface protrudes toward the substrate 301.

Subsequently, the substrate bonding device 100 brings the bonding surface of the substrate 301 with the substrate 302 into contact with the bonding surface of the substrate 302 with the substrate 301 by moving the head 402 downward by the elevating drive unit 406 (contact step). ) (Step S10). Here, as shown in FIG. 13A, the substrate bonding device 100 brings the central portions of the bonding surfaces of the two substrates 301 and 302 into contact with each other. At this time, the substrate 301 and the substrate 302 are in a state in which their central portions are temporarily joined to each other. Here, the "temporary bonding state" means a state in which the substrates 301 and 302 are bonded to each other in a state in which the substrate 302 can be separated from the substrate 301.

After that, the substrate bonding apparatus 100 measures the amount of misalignment of the substrate 302 with respect to the substrate 301 in a state where the bonding surface of the substrate 301 is in contact with the bonding surface of the substrate 302 (measurement step) (step S11). At this time, the substrate bonding device 100 measures the amount of misalignment of the substrates 301 and 302 in a state where the movement of the substrate 302 with respect to the substrate 301 is restricted by the progress of the temporary bonding between the substrate 301 and the substrate 302.

Next, the wafer bonding apparatus 100 determines whether or not all of the calculated displacement amounts Δx, Δy, and Δθ are equal to or less than the preset displacement amount thresholds Δxth, Δyz, and Δθth (step S12).

It is assumed that any of the calculated displacement amounts Δx, Δy, and Δθ is determined by the wafer bonding apparatus 100 to be larger than the preset displacement amount thresholds Δxth, Δyz, and Δθth (step S12: No). In this case, the substrate bonding device 100 separates the bonding surface of the substrate 302 from the bonding surface of the substrate 301 (disengagement step) (step S13). At this time, the substrate bonding device 100 raises the head 402 to widen the gap between the substrates 301 and 302, and bury the first pressing portion 431a in the stage 401 (see the arrow AR51 in FIG. 13B). Along with the movement, the second pressing portion 432a is moved in the direction of being embedded in the head 402 (see the arrow AR52 in FIG. 13B). Here, the substrate bonding device 100 controls the rise of the head 402 so that the tensile pressure of the substrate 302 when the substrate 302 is peeled off from the substrate 301 becomes constant. Further, the substrate bonding device 100 restarts the adsorption of the substrates 301 and 302 by the suction portions 440a and 440b on the central portion side of the stage 401 and the suction portions 440a and 440b on the central portion side of the head 402. Here, the timing at which the substrate bonding device 100 resumes the suction of the substrates 301 and 302 is such that the first pressing portion 431a is buried in the stage 401 while the gap between the substrates 301 and 302 is widened, and the second pressing portion 432a is placed in the head 402. It may be the timing before or after the timing of burying, or it may be at the same time. As a result, as shown in FIG. 14A, the substrate 302 is separated from the substrate 301, and the contact state between the substrate 301 and the substrate 302 is released.

Subsequently, the wafer bonding apparatus 100 determines whether or not the series of processes from step S9 to step S13 has been repeated a preset number of times (step S14). That is, the substrate bonding device 100 determines whether or not the contact between the substrates 301 and 302, the calculation of the amount of misalignment of the substrates 301 and 302, and the detachment of the substrate 302 from the substrate 301 are repeated a preset number of times. .. When the substrate bonding apparatus 100 determines that the number of repetitions of the series of processes from step S9 to step S13 has not reached the preset number of times (step S14: No), the substrate bonding device 100 executes the process of step S9 again.

On the other hand, it is assumed that the substrate bonding apparatus 100 determines that the number of repetitions of the series of processes from step S9 to step S13 has reached a preset number of times (step S14: Yes). In this case, the wafer bonding apparatus 100 calculates representative values (second representative values) Δxc, Δyc, and Δθc of a plurality of misalignment amounts obtained by repeatedly executing a series of processes from step S9 to step S13 (2nd representative value). Second representative value calculation step) (step S15). Here, the wafer bonding device 100 calculates an average value or an intermediate value of the measured values of a plurality of misalignment amounts.

After that, the wafer bonding apparatus 100 calculates the correction movement amount of the substrates 301 and 302 for making all of the calculated representative values Δxc, Δyc, and Δθc equal to or less than the displacement amount thresholds Δxth, Δyz, and Δθth. Step S16). Here, the control unit 700 has representative values Δxc, Δyc, Δθc of the amount of misalignment between the substrate 301 and the substrate 302 when the substrate 302 is in contact with the substrate 301, and the substrate 302 is not in contact with the substrate 301. The correction movement amount is calculated so as to move by the movement amount corresponding to the difference between the positional deviation amount between the substrate 301 and the substrate 302 in the state. In this way, by offsetting and aligning by the amount of movement corresponding to the difference between the amount of misalignment when the substrates 301 and 302 are in contact with each other and the amount of misalignment when the substrates 301 and 302 are not in contact with each other. If the same misalignment due to the contact of the substrates 301 and 302 occurs when the substrates 301 and 302 come into contact with each other again, the misalignment of the substrates 301 and 302 will be eliminated.

Next, the substrate bonding device 100 is in a non-contact state of the two substrates 301 and 302, that is, in a state where the two substrates 301 and 302 are freely movable in the horizontal direction, and the relative positions of the two substrates 301 and 302 are relative to each other. Alignment is executed so as to correct the deviation amounts Δx, Δy, and Δθ (step S17). Here, the wafer bonding device 100 moves the head 402 in the X direction, the Y direction, and the rotation direction around the Z axis by the correction movement amount calculated in step S16 while the stage 401 is fixed. In this way, in the substrate bonding apparatus 100, the substrate 302 of the substrate 301 is arranged so that the representative values Δxc, Δyc, and Δθc of the amount of misalignment are reduced in a state where the bonding surface of the substrate 301 and the bonding surface of the substrate 302 are separated from each other. Adjust the relative position with respect to (position adjustment step). Then, the wafer bonding apparatus 100 executes the process of step S9 again.

On the other hand, it is assumed that the substrate bonding apparatus 100 determines that all of the calculated misalignment amounts Δx, Δy, and Δθ are equal to or less than the preset misalignment amount thresholds Δxth, Δys, and Δθth (step S12: Yes). In this case, the substrate bonding device 100 joins the bonding surface of the substrate 301 with the substrate 302 to the bonding surface of the substrate 302 with the substrate 301 by pressurizing and heating the two substrates 301 and 302 (bonding). Step) is executed (step S19). Here, as shown in FIG. 14 (B), the substrate bonding apparatus 100 brings the entire bonding surfaces of the substrates 301 and 302 into contact with each other by stopping the suction unit 440d adsorbing the substrates 301 and 302. To do. After that, the substrate bonding apparatus 100 applies pressure to the substrates 301 and 302 in a state where the entire bonding surfaces of the substrates 301 and 302 are in contact with each other, and heats the substrates 301 and 302 by the heaters 421 and 422.

Next, the operation of the wafer bonding device 100 according to the present embodiment will be described with reference to specific examples. Here, it is assumed that the head 402 vibrates with respect to the stage 401 as shown in FIG. 15 (A). Note that FIG. 15A shows how the head 402 vibrates (see arrow AR7) between the positions Pos1 and Pos2 with respect to the stage 401. When the head 402 vibrates with respect to the stage 401, as shown in FIG. 15B, the relative misalignment amount W of the substrates 301 and 302 changes with time.

When the substrate bonding apparatus 100 repeats a series of processes from step S9 to step S14 five times, for example, from time t0 to time t1, the misalignment amount W of the substrates 301 and 302 becomes equal to or less than the misalignment amount threshold value Wth. Suppose it didn't. In this case, the wafer bonding apparatus 100 calculates a representative value W1 of the amount of misalignment obtained by repeating a series of processes from step S9 to step S14 five times. Then, the wafer bonding device 100 moves the head 402 with respect to the stage 401 by a correction movement amount corresponding to the calculated representative value W1 of the misalignment amount. After that, when the substrate bonding apparatus 100 repeated a series of processes from step S9 to step S14 five times again between the time t1 and the time t2, the misalignment amount W of the substrates 301 and 302 was the misalignment amount threshold value. It is assumed that the value does not fall below Wth. In this case, the wafer bonding apparatus 100 calculates a representative value W2 of the amount of misalignment obtained by repeating a series of processes from step S9 to step S14 five times. Then, the wafer bonding device 100 moves the head 402 with respect to the stage 401 by a correction movement amount corresponding to the calculated representative value W2 of the misalignment amount. After that, when the substrate bonding apparatus 100 executes a series of processes from step S9 to step S12 after time t2, the misalignment amount W is within the misalignment amount threshold value Wth (FIG. 15B). (Refer to the black circle in), execute the joining process.

As described above, when the head 402 vibrates with respect to the stage 401 and the substrate 302 vibrates with respect to the substrate 301, the measured value of the amount of misalignment of the substrate 301 with respect to the substrate 302 depends on the timing of the measurement. Can fluctuate. Therefore, for example, in the case of a configuration in which the measurement of the misalignment amount of the substrate 301 with respect to the substrate 302 is executed only once and the relative position of the substrate 302 with respect to the substrate 301 is adjusted based on the misalignment amount obtained thereby, the misalignment amount is measured. The effect of the amount of misalignment due to the measurement timing is likely to occur. On the other hand, in the wafer bonding apparatus 100 according to the present embodiment, the position measuring unit measures the amount of misalignment of the first substrate with respect to the second substrate in a state where the first substrate and the second substrate are in contact with each other. Repeat multiple times. Then, in the wafer bonding device 100, the substrate bonding device 100 reduces the representative value of the plurality of misalignment amounts obtained by repeatedly performing the measurement of the misalignment amount of the substrate 301 with respect to the substrate 302 a plurality of times by the position measurement unit 500. The relative position of the 302 with respect to the substrate 301 is adjusted. As a result, even when the substrate 302 vibrates with respect to the substrate 301, the influence of the error of the displacement amount due to the measurement timing of the displacement amount is reduced. Can be joined.

When the head 402 vibrates with respect to the stage 401 and the substrate 302 vibrates with respect to the substrate 301, for example, as shown in FIG. 14B, the substrates 301 and 302 are in contact with each other. The amount of misalignment of the substrate 301 with respect to the substrate 302 may vary depending on the timing at which the substrates 301 and 302 are brought into contact with each other. Therefore, for example, in the case of a configuration in which the substrates 301 and 302 are brought into contact with each other to measure the amount of misalignment, and the relative position of the substrate 302 with respect to the substrate 301 is adjusted based on the amount of misalignment each time, the substrate 302 is relative to the substrate 301. The corrected movement amount is affected by an error in the amount of misalignment due to the timing at which the substrates 301 and 302 are brought into contact with each other. Then, the number of times of repeating the adjustment of the relative position of the substrate 302 with respect to the substrate 301 increases until the displacement amount of the substrates 301 and 302 becomes equal to or less than the preset displacement amount threshold value, and the substrates 301 and 302 are joined to each other. There is a risk that the time required will be long.

On the other hand, in the substrate bonding apparatus 100 according to the present embodiment, the bonding surface of the substrate 301 is in contact with the bonding surface of the substrate 302, the amount of displacement of the substrate 301 with respect to the substrate 302 is measured, and the bonding surface of the substrate 302 is transferred from the substrate 301. A representative value of a plurality of misalignments obtained by repeatedly executing the detachment of the above is calculated. Then, the wafer bonding device 100 adjusts the relative position of the wafer bonding device 302 with respect to the wafer bonding device 301 so that the calculated representative value becomes smaller. After that, the substrate bonding apparatus 100 contacts the bonding surface of the substrate 301 with the bonding surface of the substrate 302 until the representative value of the plurality of misalignment amounts described above becomes equal to or less than a preset displacement amount threshold value. The measurement of the displacement amount with respect to the substrate 302, the detachment of the substrate 302 from the substrate 301, the calculation of the representative values of the plurality of displacement amounts, and the adjustment of the relative position of the substrate 302 with respect to the substrate 301 are repeated. As a result, even when the substrate 302 vibrates with respect to the substrate 301, the influence of an error in the amount of misalignment due to the timing at which the substrates 301 and 302 are brought into contact with each other is reduced. Therefore, the number of times of repeating the adjustment of the relative position of the substrate 302 with respect to the substrate 301 is reduced until the displacement amount of the substrates 301 and 302 becomes equal to or less than the preset displacement amount threshold value. There is an advantage that the time required for joining can be shortened.

Further, in the substrate bonding apparatus 100 according to the present embodiment, the bonding between the substrate 301 and the substrate 302 progresses, and the movement of the substrate 302 with respect to the substrate 301 is restricted by the frictional force generated between the substrate 301 and the substrate 302. With the substrate 302 pressed against the substrate 301, the amount of misalignment of the substrates 301 and 302 is measured. As a result, when the substrate 302 vibrates with respect to the substrate 301, the influence of the vibration on the measured value of the displacement amount of the substrate 302 with respect to the substrate 301 is reduced, so that the substrates 301 and 302 have high positional accuracy. Can be joined with.

(Embodiment 2)
The configuration of the wafer bonding system and the wafer bonding apparatus according to the present embodiment is the same as the configuration of the wafer bonding apparatus 100 described in the first embodiment shown in FIGS. 1 to 5 and 8. However, the operation of the wafer bonding device is different from the operation of the wafer bonding device 100 described in the first embodiment. In the following description, each configuration of the wafer bonding apparatus according to the present embodiment will be described using the same reference numerals as those shown in FIGS. 1 to 5 and 8.

The wafer bonding process executed by the wafer bonding apparatus 100 according to the present embodiment will be described with reference to FIG. Similar to the first embodiment, this wafer bonding process is started when the control unit starts a program for executing the wafer bonding process. In FIG. 16, it is assumed that the above-mentioned rough alignment operation has already been executed. After the rough alignment operation, the two substrates 301 and 302 are arranged so as to face each other in a non-contact state.

First, as shown in FIG. 16, the wafer bonding apparatus 100 executes a series of processes from step S201 to step S211. The content of each process from step S201 to step S211 is the same as the content of each process from step S1 to step S11 described in the first embodiment.

After executing the process of step S211, the wafer bonding apparatus 100 determines whether or not all of the calculated misalignment amounts Δx, Δy, and Δθ are equal to or less than the preset misalignment amount thresholds Δxth, Δys, and Δθth. (Step S212). Here, the control unit 700 first compares the position shift amount thresholds Δxth, Δyz, and Δθth stored in the auxiliary storage unit 703 with the calculated position shift amounts Δx, Δy, and Δθ. Then, the control unit 700 determines whether or not all of the calculated misalignment amounts Δx, Δy, and Δθ are equal to or less than the corresponding misalignment amount thresholds Δxth, Δys, and Δθth, respectively, based on the comparison result.

It is assumed that any of the calculated displacement amounts Δx, Δy, and Δθ is determined by the wafer bonding apparatus 100 to be larger than the preset displacement amount thresholds Δxth, Δyz, and Δθth (step S212: No). In this case, the substrate bonding device 100 separates the substrate 302 from the substrate 301 (step S213). The content of the process in step S213 is the same as the content of the process in step S13 described in the first embodiment. As a result, the substrate 302 is separated from the substrate 301, and the contact state between the substrate 301 and the substrate 302 is released.

Next, the wafer bonding apparatus 100 calculates a correction movement amount of the substrates 301 and 302 for making all of the calculated displacement amounts Δx, Δy, and Δθ equal to or less than the displacement amount thresholds Δxth, Δys, and Δθth (step S214). ). Here, the control unit 700 has the displacements Δx, Δy, Δθ between the substrate 301 and the substrate 302 when the substrate 302 is in contact with the substrate 301, and the state where the substrate 302 is not in contact with the substrate 301. The corrected movement amount is calculated so as to move by the movement amount corresponding to the difference between the positional deviation amount between the substrate 301 and the substrate 302.

After that, the substrate bonding device 100 causes the two substrates 301 and 302 to be in a non-contact state, that is, in a state where the two substrates 301 and 302 are freely movable in the horizontal direction, and the relative positions of the two substrates 301 and 302 are displaced. Alignment is executed so as to correct the quantities (first representative values) Δx, Δy, and Δθ (step S215). Here, the wafer bonding device 100 adjusts the relative position of the substrate 302 with respect to the substrate 301 so that the displacement amounts Δx, Δy, and Δθ become small (position adjusting step). Then, the wafer bonding apparatus 100 executes the process of step S209 again.

On the other hand, it is assumed that the substrate bonding apparatus 100 determines that all of the calculated misalignment amounts Δx, Δy, and Δθ are equal to or less than the preset misalignment amount thresholds Δxth, Δys, and Δθth (step S212: Yes). In this case, the substrate bonding device 100 contacts the bonding surface of the substrate 301 with the substrate 302 with the bonding surface of the substrate 302 with the substrate 301 (contact step), and then pressurizes and heats the two substrates 301 and 302. As a result, a joining process for joining the substrates 301 and 302 is executed (step S216). The content of the process in step S216 is the same as the content of the process in step S19 described in the first embodiment.

According to the substrate bonding apparatus 100 according to the present embodiment, as described in the first embodiment, contact between the substrates 301 and 302, calculation of the amount of misalignment of the substrates 301 and 302, and the calculation of the displacement of the substrates 302 from the substrate 301. The operation of repeating the withdrawal a preset number of times is not executed. As a result, the time required for joining the substrates 301 and 302 is shortened as compared with the substrate bonding device 100 according to the first embodiment.

(Embodiment 3)
As shown in FIGS. 17A and 17B, the substrate bonding apparatus according to the present embodiment is implemented in that the stage 2401 and the head 2402 are not provided with the first pressing mechanism 431 and the second pressing mechanism 432. It is different from the substrate bonding apparatus 100 according to the first aspect of the above. The other configurations of the wafer bonding system and the wafer bonding apparatus according to the present embodiment are the same as the configurations of the wafer bonding apparatus 100 shown in FIGS. 1 to 5 and 8 described in the first embodiment. In the following description, the same configuration as the wafer bonding apparatus according to the present embodiment will be described using the same reference numerals as those shown in FIGS. 1 to 5 and 8.

The wafer bonding process executed by the wafer bonding apparatus 100 according to the present embodiment will be described with reference to FIGS. 17 and 18. Similar to the first embodiment, this wafer bonding process is started when the control unit starts a program for executing the wafer bonding process. In FIG. 18, it is assumed that the above-mentioned rough alignment operation has already been executed. After the rough alignment operation, the two substrates 301 and 302 are arranged so as to face each other in a non-contact state.

First, as shown in FIG. 18, the wafer bonding apparatus executes a series of processes from step S301 to step S305. The content of each process from step S301 to step S305 is the same as the content of each process from step S1 to step S5 described in the first embodiment.

Next, the substrate bonding apparatus moves the head 2402 downward to bring the substrates 301 and 302 closer to each other (step S306). As shown in FIG. 17A, the wafer bonding device 100 moves the head 2402 downward until the distance between the substrates 301 and 302 becomes a distance G12 shorter than the distance G2. This distance G12 is set to, for example, about 10 μm. Further, the wafer bonding device 100 calculates the movement amount of the head 2402 for making the distance G12 between the substrates 301 and 302 from the calculated distance G2 between the boards 301 and 302, and moves the head 2402 by the calculated movement amount. .. Subsequently, the wafer bonding apparatus executes the processes of step S307 and step S308. The contents of the processes of steps S307 and S308 are the same as the contents of the processes of steps S7 and S8 described in the first embodiment.

After that, the substrate bonding apparatus brings the heads 2402 closer to the stage 2401 to bring the substrates 301 and 302 into contact with each other as shown in FIG. 17 (B) (step S309).

Next, the substrate bonding apparatus 100 measures the amount of misalignment of the substrate 302 with respect to the substrate 301 in a state where the bonding surface of the substrate 301 is in contact with the bonding surface of the substrate 302 (measurement step) (step S310). Then, the wafer bonding apparatus determines whether or not all of the calculated displacement amounts Δx, Δy, and Δθ are equal to or less than the preset displacement amount thresholds Δxth, Δyz, and Δθth (step S311).

Here, it is assumed that any one of the calculated misalignment amounts Δx, Δy, and Δθ is determined by the wafer bonding apparatus 100 to be larger than the preset misalignment amount thresholds Δxth, Δyz, and Δθth (step S311: No). ). In this case, the substrate bonding device 100 separates the substrate 302 from the substrate 301 by moving the head 2402 away from the stage 2401 (step S312). As a result, the contact state between the substrate 301 and the substrate 302 is released. After that, the processes of steps S313 to S316 are executed. The contents of the processes of steps S313 to S316 are the same as the contents of the processes of steps S14 to S17 described in the first embodiment.

On the other hand, it is assumed that all of the calculated displacement amounts Δx, Δy, and Δθ are determined by the wafer bonding apparatus to be equal to or less than the preset displacement amount thresholds Δxth, Δyz, and Δθth (step S311: Yes). In this case, the substrate bonding apparatus executes a bonding process for bonding the substrates 301 and 302 by pressurizing and heating the two substrates 301 and 302 (step S317). Here, as shown in FIG. 17B, the substrate bonding apparatus 100 stops all of the suction portions 440a, 440b, 440c, and 440d in a state where the entire bonding surfaces of the substrates 301 and 302 are in contact with each other. After that, the substrate bonding device 100 applies pressure to the substrates 301 and 302, and heats the substrates 301 and 302 by the heaters 421 and 422.

In the substrate bonding apparatus 100 according to the present embodiment, the stage 2401 is not provided with the first pressing mechanism 431, and the head 2402 is not provided with the second pressing mechanism 432. This has the advantage of simplifying the structure of the stage 2401 and the head 2402.

(Modification example)
Although each embodiment of the present invention has been described above, the present invention is not limited to the configuration of each of the above-described embodiments. For example, in the substrate bonding device, the substrates 301 and 302 are pressed against the substrate 301 so that the movement of the substrate 302 with respect to the substrate 301 is restricted by the frictional force generated between the substrates 301 and the substrate 302. It may be configured to measure the amount of misalignment. In this case, the elevating drive unit 406 presses the substrate 302 against the substrate 301 by moving the head 402 downward. Then, the position measuring unit 500 measures the amount of misalignment of the substrates 301 and 302 while the substrate 302 is pressed against the substrate 301.

According to this configuration, even if the temporary bonding between the substrates 301 and 302 progresses to some extent and the movement of the substrate 302 with respect to the substrate 301 is not restricted, the frictional force generated between the substrate 301 and the substrate 302 causes the substrate 302 with respect to the substrate 301. Movement is restricted. As a result, the positional accuracy of joining the substrates 301 and 302 is improved.

In the first embodiment and the third embodiment, an example in which the wafer bonding apparatus executes the displacement amount calculation process in the wafer bonding process has been described. However, the wafer bonding device 100 is not necessarily limited to a configuration in which the position shift amount calculation process is executed in the wafer bonding process. For example, the wafer bonding apparatus may be configured to measure the displacement amount only once instead of executing the displacement amount calculation process shown in FIG. 9 or 16.

In each embodiment, the correction movement amount may be determined by a function that takes as an argument the amount of misalignment of the substrate 302 with respect to the substrate 301. As an argument of this function, a parameter other than the amount of misalignment of the substrate 302 with respect to the substrate 301 may be included. Examples of such a parameter include a parameter indicating an error peculiar to the moving mechanism of the stage 401 and the head 402, an error of the position measuring unit 500, and the like.

In each embodiment, the case where the holding mechanism 440 is composed of a vacuum chuck has been described, but the present invention is not limited to this, and for example, the holding mechanism may be composed of a mechanical chuck or an electrostatic chuck. Alternatively, the holding mechanism may be configured by combining at least two types of chucks among a vacuum chuck, a mechanical chuck and an electrostatic chuck. Further, in each embodiment, an example in which the holding mechanism 440 is composed of an annular suction portion 440a, 440b, 440c, 440d has been described, but the structure of the suction portion is not limited to this, for example. The structure may be such that the substrates 301 and 302 are adsorbed through holes opened at a plurality of locations on the upper surface of the stage 401 and the lower surface of the head 402.

In each embodiment, an example in which the distance measuring unit 801 measures the distance between the three parts on the upper surface of the stage 401 and the three parts on the lower surface of the head 402 has been described. However, the number of points measured by the distance measuring unit 801 is not limited to three, and may be, for example, two or less or four or more. Further, in each embodiment, a configuration has been described in which the distance between the upper surface of the stage 401 and the lower surface of the head 402 and the thickness of the substrates 301 and 302 are measured and then the distance between the substrates 301 and 302 is calculated. However, the present invention is not limited to this, and even if the substrate bonding device is configured to directly measure the distance between the substrates 301 and 302 while the substrate 301 is held by the stage 401 and the substrate 302 is held by the head 402. Good.

In each embodiment, an example in which the position measuring unit 500 has the first imaging unit 501 and the second imaging unit 502 has been described, but the configuration of the position measuring unit 500 is not limited to this, for example, the position measuring unit. However, there may be a configuration in which only one imaging unit is provided, and the captured images GAa and GAb are sequentially captured by moving the imaging unit in the X direction or the Y direction.

Further, in the embodiment, an example in which pressurization and heating of the substrates 301 and 302 are executed in the substrate bonding apparatus 100 has been described, but the present invention is not limited to this configuration. In a device different from the substrate bonding device 100, the pressure treatment and / or the heat treatment of the substrates 301 and 302 may be executed. For example, the substrate bonding device 100 may execute up to the temporary bonding of the substrates 301 and 302, and then the heat treatment may be executed in another heating device (not shown). In this case, the heat treatment is set at 180 ° C. for about 2 hours. As a result, production efficiency can be improved.

Further, in the embodiment, an example of adopting hydrophilic bonding as a bonding method between the substrates 301 and 302 has been described, but the bonding method adopted is not limited to this, and other bonding methods may be adopted. For example, a surface-activated direct bonding method may be adopted. Alternatively, a method of joining the substrates to each other via a metal or a solder-based material may be adopted.

Further, in the embodiment, the configuration in which the substrates 301 and 302 are joined in vacuum has been described, but the present invention is not limited to this, and the configurations in which the substrates 301 and 302 are joined under atmospheric pressure may be used. , It may be configured to join in an atmosphere filled with any gas.

Further, in the embodiment, the configuration in which the head 402 moves with respect to the stage 401 has been described, but the present invention is not limited to this, and for example, the configuration in which the stage 401 moves with respect to the head 402 may be used.

Further, in the embodiment, the configuration in which the piezo actuator 411 and the second pressure sensor 412 are at the same position in the horizontal plane has been described, but the present invention is not limited to this, and the position of the piezo actuator 411 and the second pressure sensor 412 in the horizontal plane are not limited to this. The position of may be different.

Further, in the embodiment, the infrared light emitted from the first imaging unit 501 and the second imaging unit 502 and reflected by the alignment marks MK1a and MK2a of the substrates 301 and 302 is emitted from the first imaging unit 501 and the second imaging unit 501 and the second imaging unit. The configuration for measuring the misalignment of the substrates 301 and 302 by detecting with 502 has been described. However, the present invention is not limited to this, and for example, infrared light irradiated from one of the substrates 301 and 302 in the thickness direction toward the alignment marks MK1a and MK2a of the substrates 301 and 302 is emitted from one of the substrates 301 and 302 in the thickness direction of the substrates 301 and 302. It may be configured to detect. Alternatively, the amount of misalignment of the substrates 301 and 302 may be measured by directly reading the alignment marks MK1a and MK2a of the substrates 301 and 302 using visible light.

Further, in the embodiment, after the substrates 301 and 302 are cleaned in the cleaning device 940, the bonding surface treatment device 600 executes the activation treatment and the hydrophilic treatment of the bonding surfaces of the substrates 301 and 302, and then the bonding surface treatment device 600 executes the activation treatment and the hydrophilic treatment. An example in which the substrates 301 and 302 are joined in the joining device 100 has been described. However, the order of cleaning, activation treatment, hydrophilic treatment, and bonding of the substrates 301 and 302 is not limited to this. For example, the bonding surfaces of the substrates 301 and 302 may be activated and hydrophilized, then the substrates 301 and 302 may be washed, and then the substrates 301 and 302 may be bonded.

Further, in the embodiment, an example in which the hydrophilic treatment of the substrates 301 and 302 is executed in the joint surface treatment device 600 has been described, but the place where the hydrophilic treatment is executed is limited to the joint surface treatment device 600. is not it. For example, the load lock chamber 910 may have a configuration in which the hydrophilization treatment of the substrates 201 and 302 is executed.

100: Substrate joining device, 200,601: Chamber, 201: Vacuum pump, 202B, 202C: Exhaust pipe, 203B, 203C: Exhaust valve, 301,302: Substrate, 401,603,2401: Stage, 402,2402: Head , 403: Stage drive unit, 404: Head drive unit, 405: XY direction drive unit, 406: Lifting drive unit, 407: Rotation drive unit, 408: First pressure sensor, 411: Piezo actuator, 412: Second pressure sensor , 420: Substrate heating unit, 421, 422: Heater, 431: First pressing mechanism, 431a: First pressing unit, 431b: First pressing drive unit, 432: Second pressing mechanism, 432a: Second pressing unit, 432b : Second pressing drive unit, 440: Holding mechanism, 440a, 440b, 440c, 440d: Suction unit, 500: Position measurement unit, 501: First imaging unit, 502: Second imaging unit, 503: Window unit, 504 505: Mirror, 600: Joint surface treatment device, 610: Activation treatment unit, 611: Plasma source, 612: Trap plate, 613: Bias power supply, 620: Hydrophilization treatment unit, 621: Water vapor generator, 622: Supply Valve, 623: Supply pipe, 700: Control unit, 701: MPU, 702: Main storage unit, 703: Auxiliary storage unit, 704: Interface, 705: Bus, 800: External alignment device, 801: Distance measurement unit, 802: Substrate thickness measuring unit, 810: Edge recognition sensor, 910: Load lock chamber, 920: Second transfer device, 921: Vacuum transfer robot, 930: First transfer device, 931: Atmospheric transfer robot, 940: Cleaning device, 950 : Inverter, 961: Introduction port, 962: Extraction port, GAa, GAb: Captured image, MK1a, MK1b, MK2a, MK2b: Alignment mark

Claims (13)

This is a substrate bonding method for joining a first substrate provided with a first alignment mark and a second substrate provided with a second alignment mark.
A measurement step in which the measurement of the relative misalignment amount of the first substrate with respect to the second substrate from the relative misalignment amount of the first alignment mark with respect to the second alignment mark is repeated a plurality of times.
A first representative value calculation step for calculating a first representative value of a plurality of relative misalignment amounts obtained by repeating the measurement of the relative misalignment amount a plurality of times.
A position adjusting step of adjusting the relative position of the first substrate with respect to the second substrate so that the first representative value becomes smaller, and
When the first representative value is equal to or less than a preset displacement amount threshold value, a contact step of bringing the bonding surface of the first substrate with the second substrate into contact with the bonding surface of the second substrate with the first substrate. And, including
Wafer bonding method. The second substrate is vibrating with respect to the first substrate.
The substrate bonding method according to claim 1. In the measurement step, the relative displacement amount of the first substrate with respect to the second substrate is measured based on the captured image including the first alignment mark and the second alignment mark imaged by the imaging unit. ,
The substrate bonding method according to claim 1 or 2. A substrate bonding method for bonding a first substrate and a second substrate vibrating with respect to the first substrate.
A contact step in which the joint surface of the first substrate with the second substrate is brought into contact with the joint surface of the second substrate with the first substrate.
A measurement step of measuring the amount of misalignment of the first substrate with respect to the second substrate in a state where the joint surface of the first substrate is in contact with the joint surface of the second substrate.
A joining step of joining the joining surface of the first substrate with the second substrate to the joining surface of the second substrate with the first substrate.
A detachment step of separating the joint surface of the first substrate from the joint surface of the second substrate, and
A second representative value calculation step for calculating a second representative value of a plurality of misalignment amounts obtained by repeatedly executing the contact step, the measurement step, and the detachment step a plurality of times.
A position adjusting step of adjusting the relative position of the first substrate with respect to the second substrate so that the second representative value becomes smaller in a state where the bonding surface of the first substrate and the bonding surface of the second substrate are separated from each other. And, including
If the previous SL positional deviation amount is greater than a preset positional deviation amount threshold, the higher withdrawal Engineering, pre Symbol repeatedly contacting step and the measurement step executed, if the positional displacement amount is less than the positional deviation amount threshold If the misalignment amount is larger than the misalignment amount threshold even after the joining step is performed and the detaching step, the contacting step, and the measuring step are repeatedly executed a plurality of preset times , the second Perform the representative value calculation step and the position adjustment step.
Wafer bonding method. In the measurement step, as the temporary bonding between the first substrate and the second substrate progresses, the movement of the second substrate with respect to the first substrate is restricted, and the second substrate vibrates with respect to the first substrate. Measure the amount of misalignment in the state where it is not.
The substrate bonding method according to claim 4. In the measurement step, the frictional force generated between the first substrate and the second substrate restricts the movement of the second substrate with respect to the first substrate, and the second substrate vibrates with respect to the first substrate. The amount of misalignment is measured while the second substrate is pressed against the first substrate so that the second substrate is not in the state of being pressed.
The substrate bonding method according to claim 4. In the joining step, the first substrate and the second substrate are main-bonded by performing at least one of pressurization and heating.
The substrate bonding method according to any one of claims 4 to 6. The second representative value is an intermediate value or an average value.
The substrate bonding method according to any one of claims 4 to 7. Prior to the contact step, a hydrophilization treatment step of adhering water or an OH-containing substance to the joint surface of the first substrate and the joint surface of the second substrate is further included.
The substrate bonding method according to any one of claims 1 to 8. A substrate bonding device that joins a first substrate provided with a first alignment mark and a second substrate provided with a second alignment mark.
A first support base that supports the first substrate and
A second support base that is arranged to face the first support base and supports the second substrate on the side facing the first support base.
At least one of the first support and the second support is separated from the first support and the second support in the first direction in which the first support and the second support are close to each other, or the first support and the second support are separated from each other. A support base drive unit that moves in the second direction,
Amount of relative misalignment of the first alignment mark with respect to the second alignment mark The amount of misalignment of the first substrate with respect to the second substrate in a direction orthogonal to the first direction and the second direction. And the measuring unit to measure
The first representative value of the plurality of relative misalignments obtained by repeating the measurement of the relative misalignment a plurality of times by the measuring unit is reduced with respect to the second substrate of the first substrate. A position adjusting unit that adjusts relative positions in the first direction and the direction orthogonal to the second direction, and
It includes a control unit that controls the operation of each of the support base drive unit, the measurement unit, and the position adjustment unit, and calculates the first representative value.
Wafer bonding equipment. A substrate bonding device that joins a first substrate and a second substrate.
A first support base that supports the first substrate and
A second support base that is arranged to face the first support base and supports the second substrate on the side facing the first support base.
At least one of the first support and the second support is separated from the first support and the second support in the first direction in which the first support and the second support are close to each other, or the first support and the second support are separated from each other. A support base drive unit that moves in the second direction,
In a state where the support base driving unit moves at least one of the first support base and the second support base in the first direction so that the first substrate and the second substrate are in contact with each other, the first A measuring unit that measures the amount of misalignment between the first substrate and the second substrate in the direction and the direction orthogonal to the second direction.
A position adjustment unit for adjusting the relative position in a direction perpendicular to the first direction and the second direction with respect to the second substrate before Symbol first substrate,
The support base drive unit, which controls the measuring section and the position adjusting section each operation, e Bei a control unit for calculating a second representative value of the plurality of positional displacement amounts, and
The control unit controls the support base drive unit, the measurement unit, and the position adjustment unit, and when the position shift amount is larger than a preset position shift amount threshold, the support base drive unit is the first. A detaching step in which the first substrate is separated from the second substrate by moving at least one of the 1 support and the second support in the second direction, and the support drive unit is the first support. The contact step of bringing the first substrate into contact with the second substrate by moving at least one of the first substrate and the second support base in the first direction, and the measuring unit is the first substrate and the second substrate. The measurement step of measuring the amount of misalignment in contact with and is repeatedly executed.
When the misalignment amount is equal to or less than the misalignment amount threshold value, a joining step of joining the first substrate to the second substrate is performed.
If the misalignment amount is larger than the misalignment amount threshold even after the detachment step, the contact step, and the measurement step are repeatedly executed a plurality of preset times, the disengagement step, the contact step, and the measurement are performed. A second representative value calculation step for calculating the second representative value of a plurality of misalignment amounts obtained by repeatedly executing the step a plurality of times, and a position adjusting unit so that the second representative value becomes smaller. A position adjusting step of adjusting the relative positions of the first substrate with respect to the second substrate in the first direction and the direction orthogonal to the second direction is performed.
Wafer bonding equipment. The support base driving unit brings the first substrate and the second substrate into contact with each other by moving at least one of the first support base and the second support base in the first direction.
In the measuring unit, the movement of the second substrate with respect to the first substrate is restricted by the progress of temporary joining between the first substrate and the second substrate, and the second substrate vibrates with respect to the first substrate. Measure the amount of misalignment in the state where it is not.
The substrate bonding apparatus according to claim 11. The support base drive unit presses the second substrate against the first substrate by moving at least one of the first support base and the second support base in the first direction.
The measuring unit measures the amount of misalignment while the second substrate is pressed against the first substrate.
The substrate bonding apparatus according to claim 11.

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