Joining device

Abstract

This joining device comprises a pressing mechanism and an alignment stage. The pressing mechanism has a suction surface for holding a first joining object, and is capable of pressing the first joining object to a surface of a second joining object by bringing the suction surface close to the surface of the second joining object. The alignment stage is a mechanism capable of adjusting the position of the pressing mechanism. Specifically, the alignment stage is provided with a piezo stage and a wide range stage that allows greater latitude in regard to position adjustment relative to the piezo stage. The piezo stage is installed in the wide range stage, and the pressing mechanism is installed in the piezo stage. In such a configuration, the joining device adjusts the position of the pressing mechanism in two phases using the wide range stage and the piezo stage.

Description

Bonding equipment

[0001] The present invention relates to a bonding technique for chips and substrates.

[0002] Patent Document 1 discloses a technology in which a chip (such as an LSI or IC) and a substrate (such as a wafer) are bonded together, their bonding surfaces are activated with plasma, and then the chip is pressed against the surface of the substrate to bond them.

[0003] Japanese Patent Application Laid-Open No. 2018-160687

[0004] In recent years, advances in miniaturization technology in the semiconductor field, along with advances in integration technology to achieve larger capacities beyond the limits of miniaturization, have created a demand for higher precision (nanometer-order precision) in the alignment of chips relative to the bonding position in bonding technology.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to significantly improve the accuracy of alignment with respect to bonding positions in bonding techniques.

[0006] A bonding apparatus according to the present invention has the following configuration (Aspect 1). The bonding apparatus includes a pressing mechanism and an alignment stage. The pressing mechanism has an adsorption surface that holds a first object to be bonded and is capable of pressing the first object to be bonded against the surface of the second object to be bonded by bringing the adsorption surface close to the surface of the second object to be bonded. The alignment stage is a mechanism that enables adjustment of the position of the pressing mechanism. Specifically, the alignment stage includes a piezoelectric stage and a wide-area stage that can adjust the position over a wider range than the piezoelectric stage. The piezoelectric stage is mounted on the wide-area stage, and the pressing mechanism is mounted on the piezoelectric stage. In this configuration, the bonding apparatus adjusts the position of the pressing mechanism in two stages, using the wide-area stage and the piezoelectric stage.

[0007] According to the above-described first aspect, the wide-area stage allows the pressing mechanism to be moved over a wide area at high speed without requiring high accuracy, and then the piezoelectric stage allows the position of the pressing mechanism to be adjusted with high accuracy (on the order of nanometers). Therefore, when aligning the first welding object with a welding position provided on the surface of the second welding object, the pressing mechanism is moved to the welding position at high speed, and then the position of the pressing mechanism with respect to the welding position can be adjusted with high accuracy using the piezoelectric stage. In other words, it is possible to achieve both high-speed movement of the pressing mechanism over a wide area and high-accuracy position adjustment of the pressing mechanism. As a result, high-accuracy alignment of the first welding object with respect to the welding position can be performed for each welding position at high speed, even when the welding positions are scattered over a wide area.

[0008] The joining device according to Aspect 1 may have the following configuration (Aspect 2). The joining device may further include a sheet holding unit that holds a peripheral edge of a sheet having the first joining object attached to its surface. In such a configuration, the joining device may hold the first joining object via the sheet by adsorbing the back surface of the sheet to the adsorption surface, and may adjust the position of the pressing mechanism by the piezo stage while elastically deforming the sheet.

[0009] According to the above-described second aspect, the wide-area stage allows the suction surface to be moved at high speed to a position where the first object to be welded attached to the sheet can be held from its back side, and then the first object to be welded can be held (suctioned) from the back side of the sheet. Even after the first object to be welded is held on the suction surface via the sheet in this manner, the position of the pressing mechanism can be adjusted by the piezo stage while elastically deforming the sheet. Therefore, the first object to be welded can be aligned with the joining position with high precision by the piezo stage without being affected by the sheet.

[0010] In the bonding device according to the above-mentioned aspect 1 or 2, the alignment stage may further include an attitude adjustment mechanism that enables the attitude of the piezo stage relative to the wide-area stage, and the attitude adjustment mechanism may be configured to support the piezo stage at three points using three piezo actuators installed on the wide-area stage (aspect 3).

[0011] According to the above-mentioned aspect 3, it is possible to adjust the orientation of the piezo stage so that the piezo stage is parallel to the wide stage.

[0012] In the bonding apparatus according to the above-mentioned aspect 3, the attitude adjustment mechanism may incorporate a pressure sensor that measures the pressure applied at three points to the piezo stage supported at three points by piezo actuators (aspect 4).

[0013] According to the above-described fourth aspect, it is possible to measure the pressure generated when the first object to be welded is pressed against the surface of the second object to be welded with the pressure sensor.

[0014] The joining device according to the above-mentioned aspect 4 may measure the pressure generated when the first joining object is pressed against the surface of the second joining object at the above-mentioned three points using pressure sensors, and feed back the three measured values ​​obtained thereby to the control of the attitude adjustment mechanism, thereby adjusting the attitude of the piezo stage so that all three measured values ​​obtained at the next pressing are within a predetermined range (aspect 5).

[0015] According to the fifth aspect, the posture of the piezoelectric stage can be adjusted so that the piezoelectric stage is parallel to the wide stage by feeding back the three measured values ​​obtained each time the first object to be welded is pressed against the surface of the second object to the control of the posture adjustment mechanism, thereby making it possible to always keep the piezoelectric stage parallel to the wide stage.

[0016] The bonding apparatus according to any one of Aspects 1 to 5 may have the following configuration (Aspect 6). The bonding apparatus may further include a detection sensor that detects alignment marks formed on the first and second objects to be bonded, and the detection sensor may be installed on the wide stage. In this configuration, the pressing mechanism may have an optical path that transmits light that is incident on the suction surface from the alignment mark side and guides it to the detection sensor.

[0017] According to the sixth aspect, it is possible to align two corresponding alignment marks (correct misalignment) while observing the two alignment marks with a detection sensor provided on the alignment stage. Therefore, it is possible to align the alignment marks while the first object to be welded is in close proximity to the second object to be welded. As a result, after alignment, it is possible to press the first object to be welded against the surface of the second object to be welded without causing misalignment. This makes it possible to significantly improve the accuracy of alignment with respect to the joining position.

[0018] According to the present invention, it is possible to significantly improve the accuracy of alignment with respect to the joining position.

[0019] Fig. 1 is a conceptual diagram showing a bonding apparatus according to an embodiment. Fig. 2 is a conceptual diagram showing the configuration at each point of an attitude adjustment mechanism that supports a piezo stage at three points. Figs. 3(A) and 3(B) are conceptual diagrams showing changes in the state of the bonding apparatus caused by the execution of a bonding process. Figs. 4(A) and 4(B) are conceptual diagrams showing changes in the state of the bonding apparatus caused by the execution of a bonding process.

[0020] 1 is a conceptual diagram showing a bonding apparatus according to an embodiment. This bonding apparatus is an apparatus that presses a chip (such as an LSI or IC; hereinafter referred to as a "first bonding object W1") against the surface of a substrate (such as a wafer; hereinafter referred to as a "second bonding object W2") to bond them together, and includes a holding mechanism 1, a pressing mechanism 2, an alignment stage 3, a detection sensor 4, and a control device 5.

[0021] The holding mechanism 1 includes a sheet holding unit 11 , a table 12 , and a drive unit 13 .

[0022] The sheet holding part 11 is a part that holds the peripheral edge of an elastically deformable sheet Sw (such as a dicing tape) in a state in which the sheet Sw is tensioned. In this embodiment, such a sheet Sw is prepared with a plurality of first objects to be welded W1 attached to one side of the sheet Sw, and is held by the sheet holding part 11 with the one side facing downward.

[0023] The table 12 is a portion that holds the second object to be welded W2 below the sheet Sw held by the sheet holding portion 11, and has a chuck function (vacuum suction, electrostatic chuck, etc.) for fixing the second object to be welded W2. Here, a circuit is formed in the second object to be welded W2, and a welding position Pt of the first object to be welded W1 is set on the surface of the second object to be welded W2 at a predetermined position corresponding to the circuit (specifically, a predetermined position that can be connected to the circuit). Therefore, the second object to be welded W2 is held on the table 12 with the welding surface with the first object to be welded W1 (the surface where the welding position Pt of the first object to be welded W1 is provided) facing upward.

[0024] The drive unit 13 is a mechanism that enables the table 12 to move up and down and adjust its position in a horizontal plane, and is composed of, for example, a ball screw and a motor. By adjusting the position of the table 12 in this manner, when one object (hereinafter referred to as the "execution object Wt") selected from the plurality of first welding objects W1 attached to the sheet Sw is to be welded at the corresponding welding position Pt, it is possible to perform a position adjustment (position adjustment that does not require high precision) to make the welding position Pt face the execution object Wt. After such a position adjustment, a highly accurate position adjustment (alignment) of the execution object Wt with respect to the welding position Pt is performed by a piezo stage 31, which will be described later.

[0025] In this embodiment, the joining device is configured to be able to press a plurality of first objects to be joined W1 attached to a sheet Sw one by one onto the surface of a second object to be joined W2. Specifically, this is as follows.

[0026] The pressing mechanism 2 includes a pressing portion 21 , a peripheral holding portion 22 , and driving portions 23 and 24 .

[0027] The pressing unit 21 is a part that presses the execution target Wt attached to the sheet Sw against the surface of the second welding target W2. Specifically, the pressing unit 21 has an adsorption surface 21p at its tip (lower end). In this embodiment, this adsorption surface 21p is configured to be able to adsorb the back surface of the sheet Sw by vacuum suction. The pressing unit 21 is also configured to be able to move up and down by the power of the drive unit 23. More specifically, the pressing unit 21 is configured to be able to move up and down independently of the peripheral holding unit 22, which will be described later.

[0028] With this pressing unit 21, the back surface of the area of ​​the sheet Sw to which the execution target Wt is attached is attracted to the attraction surface 21p, so that the execution target Wt can be held on the attraction surface 21p via the sheet Sw (see FIG. 3B). Also, by lowering the pressing unit 21 to bring the attraction surface 21p closer to the surface of the second object to be welded W2, the execution target Wt can be pressed against the surface of the second object to be welded W2 (see FIG. 4B).

[0029] The peripheral holding unit 22 is a portion that holds the peripheral area of ​​the area of ​​the sheet Sw to which the execution target Wt is attached when the execution target Wt is pressed. Specifically, the peripheral holding unit 22 has an adsorption surface 22p at its leading end (lower end). In this embodiment, this adsorption surface 22p is configured to adsorb the back surface of the sheet Sw by vacuum suction. In addition, the peripheral holding unit 22 is configured to be able to move up and down by the power of the drive unit 24.

[0030] With this peripheral holding unit 22, when the pressing unit 21 presses the execution target Wt, the periphery of the area of ​​the sheet Sw to which the execution target Wt is attached can be held in place by the adsorption surface 22p (see FIG. 4B ). This allows the sheet Sw to bend appropriately inside the adsorption surface 22p when the execution target Wt is pressed, which in turn makes it easier to peel the execution target Wt from the sheet Sw.

[0031] The alignment stage 3 is a combination of multiple stages to enable high-speed and high-precision position adjustment of the pressing mechanism 2. Specifically, the alignment stage 3 includes a piezo stage 31 and a wide-area stage 32 that allows position adjustment over a wider range than the piezo stage 31. The piezo stage 31 is mounted on the wide-area stage 32, and the pressing mechanism 2 is mounted on the piezo stage 31. The piezo stage 31 uses a piezo element as its stage drive source, allowing for high-precision (nano-order precision) stage position adjustment. On the other hand, the wide-area stage 32 uses a ball screw and a motor as its stage drive source, allowing for high-speed movement of the stage over a wide range.

[0032] With this alignment stage 3, the position of the pressing mechanism 2 can be adjusted in two stages using the wide stage 32 and the piezo stage 31. Specifically, the wide stage 32 allows the pressing mechanism 2 to be moved at high speed over a wide range without requiring high accuracy, and then the piezo stage 31 allows the position of the pressing mechanism 2 to be adjusted with high accuracy (on the order of nanometers).

[0033] Therefore, when aligning the execution object Wt with the joining position Pt provided on the surface of the second joining object W2, the wide stage 32 enables the pressing mechanism 2 to be moved at high speed to a position where the execution object Wt can be held from the back side (in other words, a position above the corresponding joining position Pt).

[0034] Furthermore, because the sheet Sw is elastically deformable, even after the execution target Wt is held on the suction surface 21p via the sheet Sw, the position of the pressing mechanism 2 (i.e., the position of the execution target Wt) can be adjusted by the piezo stage 31 while the sheet Sw is elastically deforming. Therefore, the execution target Wt can be aligned with respect to the joining position Pt with high accuracy by the piezo stage 31 without being affected by the sheet Sw. This makes it possible to significantly improve the accuracy of alignment with respect to the joining position Pt.

[0035] In this way, the welding device of this embodiment can achieve both high-speed movement of the pressing mechanism 2 over a wide range and high-precision position adjustment of the execution target Wt relative to the welding position Pt. As a result, even if the welding positions Pt are scattered over a wide range, high-precision position adjustment of the execution target Wt relative to the welding position Pt can be performed at high speed for each of the welding positions Pt.

[0036] In this embodiment, the alignment stage 3 further includes an attitude adjustment mechanism 33 that enables adjustment of the attitude of the piezo stage 31 relative to the wide stage 32. Specifically, the attitude adjustment mechanism 33 is configured to support the piezo stage 31 relative to the wide stage 32 at three points.

[0037] 2 is a conceptual diagram showing the configuration at each point of the attitude adjustment mechanism 33 that supports the piezo stage 31 at three points. At each point, the attitude adjustment mechanism 33 is configured by erecting a piezo actuator 331, which can adjust the protrusion amount of a movable part 331A, on the wide stage 32, and supporting the piezo stage 31 by bringing the tip of the movable part 331A into contact with the back surface of the piezo stage 31. The example of FIG. 2 also shows a case where a main body 331B of the piezo actuator 331 is connected to the piezo stage 31 via an annular leaf spring 332 in order to stabilize the support state of the piezo stage 31 by the piezo actuator 331.

[0038] Such an attitude adjustment mechanism 33 makes it possible to adjust the attitude of the piezo stage 31 so that the piezo stage 31 is parallel to the wide stage 32 .

[0039] Furthermore, when the execution target Wt is pressed against the surface of the second object to be welded W2, a force (reaction force) equivalent to the pressure generated at that time is concentrated at three points where the piezo stage 31 is supported by the piezo actuator 331. Therefore, the attitude adjustment mechanism 33 is equipped with a pressure sensor 333 that measures the pressure applied to the piezo stage 31 at three points (see FIG. 2). This makes it possible for the pressure sensor 333 to measure the pressure generated when the execution target Wt is pressed against the surface of the second object to be welded W2.

[0040] The detection sensor 4 is a sensor that detects alignment marks formed on the first welding object W1 and the second welding object W2. Specifically, the detection sensor 4 is an image sensor that detects light from a light source 41 that creates an image or shadow of the alignment mark, thereby acquiring an image including the image or shadow of the alignment mark. In this embodiment, IR light (infrared light) is used as the light from the light source 41, and materials that can transmit IR light are used for the sheet Sw and the table 12. Note that the IR light may be extracted by passing the light from the light source 41 through a bandpass filter.

[0041] The detection sensor 4 is also installed on the wide stage 32 together with the piezo stage 31. Therefore, when it is desired to obtain an image including an image of the alignment mark with the detection sensor 4, the light source 41 is positioned so that light is irradiated onto the alignment mark from the rear side (upper side in FIG. 1 ) of the sheet Sw. This allows the detection sensor 4 to detect light reflected from the alignment mark. On the other hand, when it is desired to obtain an image including the shadow of the alignment mark with the detection sensor 4, the light source 41 is positioned so that light is irradiated onto the alignment mark from the rear side (lower side in FIG. 1 ) of the table 12. This allows the detection sensor 4 to detect transmitted light that casts a shadow on the alignment mark.

[0042] Furthermore, in this embodiment, light incident on the suction surface 21p of the pressing unit 21 from the alignment mark side is used to acquire an image (an image including an image of the alignment mark or a shadow) by the detection sensor 4. Specifically, this is as follows: The pressing mechanism 2 is formed with an optical path Lx that transmits light incident on the suction surface 21p of the pressing unit 21 from the alignment mark side and guides it to the detection sensor 4 (see FIG. 1 ). To achieve this, in this embodiment, the pressing unit 21 is made of a material (such as quartz or acrylic) that can transmit IR light.

[0043] Such a detection sensor 4 and related configuration make it possible to align two corresponding alignment marks (correct misalignment) while observing the two alignment marks with the detection sensor 4 provided on the wide stage 32. Therefore, alignment of the alignment marks can be performed while the execution target Wt is in close proximity to the second welding target W2 (see FIG. 4A). As a result, after alignment, the execution target Wt can be pressed against the surface of the second welding target W2 without causing misalignment therefrom (see FIG. 4B). This makes it possible to significantly improve the accuracy of alignment with respect to the welding position Pt.

[0044] The control device 5 is composed of a processing device (such as a CPU) and a storage device (such as a RAM or a ROM), and controls each part of the bonding apparatus (such as the holding mechanism 1, the pressing mechanism 2, the alignment stage 3, and the detection sensor 4) in accordance with a control program installed in the bonding apparatus. In this embodiment, the control device 5 can execute the bonding process described below.

[0045] Here, before being installed in the bonding device, the control program may be stored in a readable state on a portable storage medium (for example, a flash memory, etc.), or may be stored in a downloadable state on another server, etc. The bonding process described below is not limited to being realized by software through the execution of a program, but may also be realized by hardware using a processing circuit built in the bonding device.

[0046] [1-2] Bonding Process FIGS. 3A to 4B are conceptual diagrams sequentially showing the state changes of the bonding device that occur as the bonding process is performed.

[0047] When the joining process is started, the control device 5 first controls the wide stage 32 to move the pressing mechanism 2 at high speed to a position where the execution target Wt can be held from the back side (in other words, a position above the corresponding joining position Pt) in order to align the execution target Wt with the joining position Pt provided on the surface of the second welding target W2 (step S101, see FIG. 3A). At this time, the control device 5 adjusts the position of the table 12 holding the second welding target W2 by controlling the drive unit 13 while observing both the alignment marks provided on the execution target Wt and the joining position Pt with the detection sensor 4, thereby also performing position adjustment (position adjustment that does not require high precision) to make the joining position Pt face the execution target Wt.

[0048] After step S101, the control device 5 controls the drive units 23 and 24 of the pressing mechanism 2 to lower the pressing unit 21 and the peripheral holding unit 22, thereby causing the back surface of the area of ​​the sheet Sw to which the execution target Wt is attached to be adsorbed onto the suction surface 21p of the pressing unit 21, and the back surface of the surrounding area to be adsorbed onto the suction surface 22p of the peripheral holding unit 22 (step S102, see FIG. 3B). As a result, the execution target Wt is held by the suction surface 21p of the pressing unit 21 via the sheet Sw, and the area of ​​the sheet Sw surrounding the area to which the execution target Wt is attached is held by the suction surface 22p of the peripheral holding unit 22.

[0049] After step S102, the control device 5 controls the piezo stage 31 to adjust the position of the pressing mechanism 2 with high precision (nanometer-order precision) (step S103; see FIG. 4A). Specifically, the control device 5 adjusts the position of the execution target Wt with high precision while observing the alignment marks provided on both the execution target Wt and the joining position Pt with the detection sensor 4 so that the two corresponding alignment marks accurately overlap. This allows the execution target Wt to ​​be aligned with the joining position Pt with high precision.

[0050] After step S103, the control device 5 controls the drive unit 23 of the pressing mechanism 2 to lower the pressing unit 21, thereby pressing the execution target Wt against the surface of the second welding target W2 (step S104, see FIG. 4(B)). At this time, the control device 5 lowers the pressing unit 21 until the output of the pressure sensor 333 reaches the target value (in other words, until the pressing force reaches the target value).

[0051] In step S104, the control device 5 keeps the peripheral holding unit 22 in the same position when lowering the pressing unit 21. This allows the sheet Sw to bend appropriately inside the adsorption surface 22p when pressing the execution target Wt, which in turn makes it easier to peel the execution target Wt from the sheet Sw.

[0052] The control device 5 performs such joining processing (steps S101 to S104) on each of the plurality of first objects to be joined W1 attached to the sheet Sw.

[0053] [2] Modifications [2-1] First Modification In the control process described above, the control device 5 may perform the following process. The control device 5 may measure the pressure generated during pressing in step S104 using pressure sensors 333 at three points supporting the piezo stage 31, and feed back the three measured values ​​obtained thereby to the control of the attitude adjustment mechanism 33, thereby adjusting the attitude of the piezo stage 31 so that all three measured values ​​obtained during the next pressing are values ​​within a predetermined range. Here, the predetermined range is a range set so that it is permissible to estimate that the piezo stage 31 is parallel to the wide stage 32 when all three measured values ​​are within that range.

[0054] Specifically, the control device 5 can adjust the amount of protrusion of the movable part 331A of each piezo actuator 331 based on an amount that can be calculated using three measurement values ​​(such as the deviation of the measurement value from a reference value (such as a central value) within a specified range, or the difference between the measurement values) so that all three measurement values ​​obtained at the next pressing are within a specified range.

[0055] According to this control process, each time the execution target Wt is pressed against the surface of the second welding target W2, the three measured values ​​obtained at that time are fed back to the control of the attitude adjustment mechanism 33, thereby making it possible to adjust the attitude of the piezo stage 31 so that the piezo stage 31 is parallel to the wide stage 32. This makes it possible to always keep the piezo stage 31 parallel to the wide stage 32.

[0056] [2-2] Second Modification The above-described joining device may be appropriately modified to join the first joining object W1 and the second joining object W2 with their joining surfaces facing laterally (horizontally).

[0057] [2-3] Third Modification The above-described joining device may be appropriately modified to hold the object Wt on the suction surface 21p of the pressing unit 21, and then adjust the position of the object Wt (transport and alignment) in two stages using the wide stage 32 and the piezo stage 31.

[0058] [2-4] Fourth Modification The above-described bonding device is not limited to the case of bonding a chip (first bonding object W1) to a substrate (second bonding object W2), but can also be applied to the case of bonding a chip (first bonding object W1) to another chip (second bonding object W2).

[0059] The above-described embodiments and modifications should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined not by the above-described embodiments and modifications, but by the claims. Furthermore, the scope of the present invention is intended to include all modifications that are equivalent to the scope of the claims and fall within the scope thereof.

[0060] Furthermore, from the above-described embodiments and variations, a portion of the configuration of the joining device may be extracted as the subject of the invention, or a portion or all of the joining process, or a program for executing them, etc. may be extracted.

[0061] REFERENCE SIGNS LIST 1 Holding mechanism 2 Pressing mechanism 3 Alignment stage 4 Detection sensor 5 Control device 11 Sheet holding section 12 Table 13 Driving section 21 Pressing section 21p Suction surface 22 Periphery holding section 22p Suction surface 23, 24 Driving section 31 Piezo stage 32 Wide stage 33 Attitude adjustment mechanism 41 Light source Lx Light path Pt Joining position Sw Sheet W1 First joining object W2 Second joining object Wt Execution object 331 Piezo actuator 331A Movable section 331B Main body 332 Leaf spring 333 Pressure sensor

Claims

1. A bonding device comprising: a pressing mechanism that has an adsorption surface that holds a first object to be joined, and that is capable of pressing the first object to be joined against the surface of a second object to be joined by bringing the adsorption surface close to the surface of the second object to be joined; and an alignment stage that enables the position of the pressing mechanism to be adjusted, wherein the alignment stage comprises a piezo stage and a wide-range stage that is capable of adjusting its position over a wider range than the piezo stage, the piezo stage is installed on the wide-range stage, and the pressing mechanism is installed on the piezo stage, and the position of the pressing mechanism is adjusted in two stages by the wide-range stage and the piezo stage.

2. The joining device according to claim 1, further comprising a sheet holding section that holds the peripheral edge of a sheet having the first joining object attached to its surface, wherein the back surface of the sheet is adsorbed to the adsorption surface to hold the first joining object via the sheet, and while maintaining this state, the position of the pressing mechanism is adjusted by the piezo stage while elastically deforming the sheet.

3. A bonding device according to claim 1 or 2, wherein the alignment stage further comprises an attitude adjustment mechanism that enables the attitude of the piezo stage relative to the wide stage, and the attitude adjustment mechanism is configured to support the piezo stage at three points using three piezo actuators installed on the wide stage.

4. A bonding device according to claim 3, wherein the attitude adjustment mechanism incorporates pressure sensors that measure the pressure applied to the piezo stage, which is supported at three points by the piezo actuator, at three points.

5. A bonding device as described in claim 4, wherein the pressure generated when the first object to be bonded is pressed against the surface of the second object to be bonded is measured at the three points by the pressure sensors, and the three measured values ​​obtained thereby are fed back to the control of the attitude adjustment mechanism, thereby adjusting the attitude of the piezo stage so that all three measured values ​​obtained at the next pressing are within a predetermined range.

6. A bonding device according to any one of claims 1 to 5, further comprising a detection sensor that detects alignment marks formed on the first bonding object and the second bonding object, the detection sensor being installed on the wide stage, and the pressing mechanism having an optical path formed therein for transmitting light incident on the suction surface from the alignment mark side and guiding the light to the detection sensor.

Images