Bonding device and bonding method

Abstract

The present invention relates to a bonding device and a bonding method. The bonding device includes a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and a side wall of the bonding head, and the bottom wall of the bonding head is used to absorb a chip to be bonded, and to bond the lower surface of the chip to the upper surface of a bonding object. Before bonding, pressure is applied to the cavity to deform the bottom wall of the bonding head, and the middle area of ​​the lower surface of the chip arches toward the bonding object. When bonding, the middle area of ​​the lower surface of the chip contacts the upper surface of the bonding object before the edge area. When bonding the chip and the bonding object, the bonding method causes the middle area of ​​the lower surface of the chip to contact the upper surface of the bonding object before the edge area. Compared with the direct contact between the lower surface of the chip and the bonding object as a whole, the formation of closed bubbles can be avoided, the probability of void defects at the bonding surface is reduced, and the bonding quality is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a bonding device and a bonding method. Background Art

[0002] In the existing chip packaging technology, C2W (chip to substrate) or C2C (chip to chip) processes are used as needed. In particular, the chip to substrate process is favored by global semiconductor manufacturers because it is not limited by chip size matching and its known good die (KGD) solution can greatly improve the yield.

[0003] An existing C2W or C2C mass production solution uses a micro bump packaging process. The minimum unit size (pitch size) that can be achieved by the packaging module is about 40μm. In addition, this packaging process requires an underfill under the bump, which is not conducive to heat dissipation. In order to reduce the minimum unit size and improve the heat dissipation capacity. At present, the new packaging process bonds the chip to the substrate or other chips through direct bonding (such as hybrid bonding). In this way, the minimum unit size of the packaging module can be less than 10μm, thereby achieving a higher I / O connection density, and no underfill is required, and the heat dissipation performance is also improved.

[0004] However, when the above direct bonding is performed using existing bonding equipment, bubble defects are likely to occur at the bonding surface. Summary of the invention

[0005] In order to reduce the void defects generated at the bonding surface when bonding chips and improve the chip packaging quality, the present invention provides a bonding device and a bonding method.

[0006] On the one hand, the present invention provides a bonding device, comprising a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and side walls of the bonding head, the bottom wall of the bonding head is used to adsorb a chip to be bonded, and to bond the lower surface of the adsorbed chip to the upper surface of a bonding object, wherein before the bonding, pressure is applied to the cavity so that the bottom wall of the bonding head is deformed under the action of pressure, and the middle area of ​​the lower surface of the chip is arched toward the bonding object, and the middle area contacts the upper surface of the bonding object before the edge area of ​​the lower surface of the chip.

[0007] Optionally, air pressure or hydraulic pressure is applied to the cavity.

[0008] Optionally, the bottom wall of the bonding head includes two first material zones arranged in a first direction and a second material zone located between the two first material zones, the two first material zones are connected to the side walls of the bonding head, the second material zone is connected to the side walls of the bonding head in the first direction through the two first material zones respectively, the second material zone is directly connected to the side walls of the bonding head in a second direction perpendicular to the first direction, and the yield strength of the first material zone is less than the yield strength of the second material zone.

[0009] Optionally, the middle area of ​​the lower surface of the chip is arched with an amplitude of 1 μm to 10 μm.

[0010] Optionally, a plurality of adsorption holes are distributed on the lower surface of the bottom wall of the bonding head, each of the adsorption holes is connected to a vacuum system to adsorb the chip, and the vacuum system is isolated from the inside of the cavity.

[0011] Optionally, each of the adsorption holes passes through the bottom wall of the bonding head and is connected to a vacuum pipeline disposed in the cavity.

[0012] Optionally, the lower surface of the bottom wall of the bonding head has a groove, and the multiple adsorption holes are located in the groove.

[0013] Optionally, a suction cup is provided on the lower surface of the bottom wall of the bonding head, and the suction cup is used to absorb the chip.

[0014] In one aspect, the present invention provides a bonding method, wherein a bonding device includes a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and a side wall of the bonding head, and the bonding method includes:

[0015] Using the bottom wall of the bonding head to absorb the chip to be bonded, and moving it to the upper surface of the bonding object for alignment;

[0016] Applying pressure to the cavity so that the bottom wall of the bonding head is deformed under the pressure and the middle area of ​​the lower surface of the chip is arched toward the bonding object; and,

[0017] The chip is bonded to the bonding object, wherein the middle area contacts the upper surface of the bonding object before the edge area of ​​the lower surface of the chip contacts the upper surface of the bonding object.

[0018] Optionally, before the chip is bonded to the bonding object, the pressure applied to the cavity is stopped; during the bonding process of the chip and the bonding object, the pressure in the cavity is gradually released so that after the chip and the bonding object are bonded, the lower surface of the bonding head and the chip returns to a plane.

[0019] The bonding device provided by the present invention includes a bonding head with a cavity, wherein the cavity is surrounded by the bottom wall and side walls of the bonding head, and the bottom wall of the bonding head is used to adsorb the chip to be bonded, and to bond the lower surface of the adsorbed chip to the upper surface of a bonding object. Before the bonding, pressure is applied to the cavity to deform the bottom wall of the bonding head under the action of pressure, and the middle area of ​​the lower surface of the chip is arched toward the bonding object. When the bonding is performed, the middle area contacts the upper surface of the bonding object before the edge area of ​​the lower surface of the chip. Compared with the direct contact between the lower surface of the chip and the bonding object, the formation of closed bubbles can be avoided, the probability of void defects at the bonding surface is reduced, and the bonding quality is improved.

[0020] The bonding device used in the bonding method provided by the present invention includes a bonding head with a cavity, wherein the cavity is surrounded by the bottom wall and side walls of the bonding head. When the chip and the bonding object are bonded, the middle area of ​​the lower surface of the chip contacts the upper surface of the bonding object before the edge area, which can reduce the probability of void defects at the bonding surface and improve the bonding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of bonding a chip with a flat bottom surface to a bonding object.

[0022] Figure 2 It is a schematic diagram of bonding a chip to a bonding object using a bonding device according to an embodiment of the present invention.

[0023] Figure 3 Schematic diagram of a bonding head in a bonding device according to an embodiment of the present invention.

[0024] Figure 4 It is a schematic diagram of a bonding head in a bonding device according to another embodiment of the present invention.

[0025] Figure 5 yes Figure 4 Schematic diagram of the bottom surface of the bond head shown.

[0026] Description of reference numerals:

[0027] 10, 11-bonding head; 20, 21-chip; 30, 31-bonding object; 11a-suction cup; 12-adsorption hole; 12a-vacuum pipeline; 13-cavity; 13a-first material area; 13b-second material area; 14-groove. DETAILED DESCRIPTION

[0028] The bonding device and bonding method of the present invention are further described in detail below in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will become clearer. It should be understood that the drawings in the specification are all in a very simplified form and are not in precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. It should be noted that the order of the steps in the method presented herein is not necessarily the only order for performing these steps, and some of the steps described may be omitted and / or some other steps not described herein may be added to the method.

[0029] Figure 1 This is a schematic diagram of bonding a chip with a flat bottom surface to a bonding object. Figure 1 When the bonding head 10 adsorbs a chip 20 and bonds the chip 20 to a bonding object 30 (such as a substrate or another chip) (e.g., hybrid bonding), the lower surface of the chip 20 needs to be firstly bonded to the upper surface of the bonding object 30. However, the lower surface of the chip 20 is usually relatively flat. During bonding, if the bonding head 10 directly presses the chip down to make it contact with the bonding object 30, it is likely to cause a void defect at the bonding surface after the chip 20 and the bonding object 30 are bonded.

[0030] Figure 2 FIG. 1 is a schematic diagram of bonding a chip to a bonding object using a bonding device according to an embodiment of the present invention. Figure 2 , in order to avoid Figure 1 The bonding method shown causes the problem of void defects at the bonding surface, and improves the chip packaging quality. An embodiment of the present invention includes a bonding device, which includes a bonding head 11 with a cavity, and the cavity 13 is surrounded by the bottom wall and side walls of the bonding head 11. The bottom wall of the bonding head 11 is used to adsorb the chip 21 to be bonded, and to bond the lower surface of the adsorbed chip 21 with the upper surface of a bonding object 31. Before the bonding is performed, pressure is applied to the cavity to deform the bottom wall of the bonding head 11 under the action of pressure, and the middle area of ​​the lower surface of the chip 21 adsorbed by the bonding head 11 is arched toward the bonding object 31. When the bonding is performed, the middle area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 before the edge area of ​​the lower surface of the chip.

[0031] It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. In the present invention, the "upper surface" and the "lower surface" are opposite surfaces. In different embodiments, the bonding head 11 can be located above the bonding object 31 or below the bonding object 31. The lower surface of the chip 21 is the side of the chip 21 away from the bonding head 11 but close to the bonding object 31. The upper surface of the bonding object 31 is the side of the bonding object 31 close to the lower surface of the chip 21.

[0032] The bonding device of the embodiment of the present invention deforms the lower surface of the chip 21 before bonding the lower surface of the chip 21 to the bonding object 31. The longitudinal distance between the middle area of ​​the lower surface of the chip 21 and the upper surface of the bonding object 31 is smaller than the longitudinal distance between the edge area of ​​the lower surface of the chip 21 and the upper surface of the bonding object 31. When the chip 21 is pressed down for bonding, the middle area contacts the upper surface of the bonding object 31 before the edge area, so that the bonding wave gradually diffuses from the middle area of ​​the bonding surface of the chip 21 and the bonding object 31 to the periphery, which can avoid the formation of closed bubbles, reduce the probability of void defects at the bonding surface, and improve the bonding quality. The downward arching amplitude of the middle area of ​​the lower surface of the chip 21 is, for example, in the range of 1μm to 10μm.

[0033] In the bonding device of the embodiment of the present invention, the bonding head 11 adopts a deformable structure. For example, when the chip 21 to be bonded is adsorbed, the chip 21 is transferred, and alignment is performed before bonding, the bottom wall of the bonding head 11 does not deform. At this time, the lower surface of the bottom wall of the bonding head 11 is, for example, a plane, and the lower surface of the adsorbed chip 21 is also a plane. When the alignment is completed and before the chip 21 is pressed down to the upper surface of the bonding object 31, pressure is applied to the cavity inside the bonding head 11 so that the bottom wall of the bonding head is deformed under the action of pressure, thereby deforming the adsorbed chip 21, specifically, the middle area of ​​the lower surface of the chip 21 is arched downward, and at this time, the longitudinal cross-sectional shape of the lower surface of the chip 21 at least at one angle becomes an arch or arc (the longitudinal cross-sectional shape before deformation can be regarded as a straight line). In order to apply pressure to the cavity to deform the bottom wall of the bonding head, the bonding device may include a pneumatic system or a hydraulic system (not shown) connected to the cavity of the bonding head 11, and pneumatic pressure or hydraulic pressure is applied to the cavity so that the bottom wall of the bonding head is deformed under the action of the pneumatic pressure or hydraulic pressure. For example, pressure can be applied by passing a fluid into the cavity, and the fluid can be a gaseous fluid such as air or nitrogen, or a liquid fluid such as water or oil.

[0034] In order to adsorb the chip 21 and facilitate the release of the chip 21 after the chip 21 and the bonding object 31 are bonded, the bonding device may also include a vacuum system (not shown). The vacuum system and the air pressure system or hydraulic system that applies pressure to the cavity operate independently, so that the bonding head 11 can adsorb the chip 21 to be bonded while the bottom wall of the bonding head 11 deforms so that the middle area of ​​the lower surface of the adsorbed chip 21 arches toward the bonding object 31. Since the chip 21 to be bonded is a bare chip, its thickness is relatively small (for example, about 100 microns). When the bottom wall of the bonding head 11 deforms, the adsorbed chip 21 will also deform, so that the middle area of ​​the lower surface of the chip 21 arches toward the bonding object 31.

[0035] Figure 3 FIG. 1 is a schematic diagram of a bonding head in a bonding device according to an embodiment of the present invention. Figure 3 In one embodiment, a suction cup 11a is provided on the lower surface of the bottom wall of the bonding head 11. The suction cup 11a is used to absorb the chip 21 to be bonded, that is, the bonding head 11 can absorb the chip 21 through the vacuum formed in the suction cup 11a. The suction cup 11a has a certain flexibility, for example. When the chip 21 is adsorbed, the edge of the suction cup 11a contacts the surface of the chip 21 and deforms, and a low vacuum is formed between the inner surface of the suction cup 11a and the surface of the enclosed chip 21, so as to facilitate the transfer of the chip 21. After the chip 21 is bonded to the bonding object 31, the low vacuum is released to separate the bonding head 11 and the chip 21. By selecting a suction cup with a suitable shape and size, the chip 21 can be made to be tightly attached to the lower surface of the bottom wall of the bonding head 11.

[0036] Figure 4 It is a schematic diagram of a bonding head in a bonding device according to another embodiment of the present invention. Figure 5 yes Figure 4 The bottom surface of the bonding head is shown in Figure 2. Figure 4 and Figure 5 In one embodiment, a plurality of adsorption holes 12 are distributed on the lower surface of the bottom wall of the bonding head 11, and the adsorption holes 12 are used to adsorb the chip 21 to be bonded. Each of the adsorption holes 12 is connected to a vacuum system, which includes a vacuum pipeline connected to the adsorption holes 12 and a vacuum pump for vacuuming, and the vacuum system is not affected by the pressure applied to the cavity 13. In this embodiment, when the lower surface of the bottom wall of the bonding head 11 is attached to the surface of the chip 21, the chip 21 can be adsorbed on the lower surface of the bonding head 11 by vacuuming the adsorption holes 12.

[0037] Reference Figure 4In this embodiment, each adsorption hole 12 passes through the bottom wall of the bonding head 11 and is connected to a corresponding vacuum pipeline 12a disposed in the cavity, that is, each adsorption hole 12 is connected to the vacuum system outside the bonding head 11 through a corresponding vacuum pipeline located in the cavity 13. It should be noted that Figure 4 Only one vacuum pipeline 12a connected to the adsorption hole 12 is shown. In fact, each adsorption hole 12 can be connected to a vacuum pipeline 12a, and multiple vacuum pipelines 12a can be connected to a vacuum pump through a total vacuum pipeline. In another embodiment, the adsorption hole 12 can be connected to a vacuum system outside the bonding head 11 through vacuum pipelines arranged in the bottom wall and side walls of the bonding head 11.

[0038] Reference Figure 5 , the lower surface of the bottom wall of the bonding head 11 may be provided with a groove 14, and the above-mentioned multiple adsorption holes 12 may be arranged in the groove 14. Furthermore, the lower surface of the bottom wall of the bonding head 11 may be provided with multiple grooves 14, and the above-mentioned multiple adsorption holes 12 may be dispersedly arranged in the multiple grooves 14. For example, one or more adsorption holes 12 are arranged in each of the grooves 14. When the chip 21 is adsorbed, the upper surface of the chip 21 covers the downward opening of the groove 14, and the groove 14 is exhausted through the adsorption holes 12 in the groove 14, and a vacuum zone can be formed in each groove 14, which helps to enhance the adsorption force on the chip 21. In an optional scheme, the number of adsorption holes 12 arranged in each groove 14 is the same, such as Figure 5 As shown, two adsorption holes 12 are provided in each groove 14 , but the present invention is not limited thereto. Depending on the size and position of the grooves, the number of adsorption holes 12 provided in each groove 14 may not be completely the same or may be different.

[0039] The pattern of each groove 14 in the lower surface plane of the bottom wall of the bonding head 11 is, for example, a line segment. Considering that a conventional chip is rectangular, when the chip 21 is adsorbed, the groove 14 can extend along the two rectangular sides of the chip 21. Figure 5 As shown, for example, in the lower surface plane of the bottom wall of the bonding head 11 , the extension direction of a portion of the grooves 14 is perpendicular to the extension direction of another portion of the grooves 14 .

[0040] The bottom wall and the side wall of the bonding head 11 can be made of different materials, so that when pressure is applied to the cavity, the deformation caused is mainly generated on the bottom wall of the bonding head 11, thereby adjusting the deformation of the chip 21 adsorbed on the lower surface of the bottom wall of the bonding head 11. By controlling the pressure applied to the cavity, the deformation amplitude can be adjusted to adapt to the deformation amount according to chips of different sizes. The shape of the side wall of the bonding head 11 is preferably not affected by the pressure applied to the cavity, and can be regarded as fixed, so that the edge of the bottom wall connected to the side wall is fixed, so that when the bottom wall of the bonding head 11 is deformed, the position of the edge of the bottom wall does not move, and the deformation of the bottom wall gradually increases from the edge of the bottom wall to the middle area of ​​the bottom wall, and the deformation reaches the maximum in the middle area of ​​the bottom wall, so that the middle area of ​​the lower surface of the bottom wall of the bonding head 11 is arched downward (toward the bonding object 31 in this embodiment), and drives the middle area of ​​the lower surface of the adsorbed chip 21 to arch downward (toward the bonding object 31 in this embodiment).

[0041] The bottom wall of the bonding head 11 can be made of at least one material selected from silicon carbide, silicon nitride and silicon oxynitride. The bottom wall of the bonding head 11 can be formed of the same material, for example, an elastic film formed of the same material; or it can be formed by splicing different materials.

[0042] Reference Figure 4 In one embodiment, the bottom wall of the bonding head 11 includes a first direction ( Figure 4 The bonding head 11 is provided with two first material regions 13a arranged in the Y direction (in the Y direction) and a second material region 13b located between the two first material regions 13a, wherein the two first material regions 13a are connected to the side wall of the bonding head 11, the second material region 13b is connected to the side wall of the bonding head 11 through the two first material regions 13a in the first direction, and the second material region 13b is connected to the side wall of the bonding head 11 in the second direction (in the Y direction) perpendicular to the first direction. Figure 4 The first material region 13a is directly connected to the side wall of the bonding head 11 in the X direction (in the X direction), and the yield strength of the first material region 13a is less than the yield strength of the second material region 13b. When pressure is applied to the cavity 13, the first material region 13a of the bottom wall of the bonding head 11 has a lower ability to resist deformation than the second material region 13b. In the case of simultaneous deformation, the deformation amount of the first material region 13a is greater than that of the second material region 13b.

[0043] Furthermore, when no pressure is applied to the cavity or the pressure is small and does not cause the first material area 13a to deform, the lower surfaces of the first material area 13a and the second material area 13a are both flat. When the pressure applied to the cavity is gradually increased, the first material area 13a deforms first, and the farther the first material area 13a is from the side wall, the greater the drop. Affected by the drop of the two first material areas 13a, the second material area 13b connected to them becomes an arched shape with a low center and high sides in the second direction, such as Figure 4 shown.

[0044] For example, when there is no pressure on the cavity inside the bonding head 11, the lower surface of the bottom wall of the bonding head 11 does not deform and is a rectangular plane, and the first direction and the second direction are respectively the two perpendicular side directions of the rectangular plane. A first material area 13a is respectively arranged on a set of opposite sides of the rectangle, and the range of each first material area 13a is, for example, surrounded by one side of the rectangle and an arc connecting the two end points of the side. The second material area 13b is located between the two first material areas 13a, a set of opposite sides of the second material area 13b is connected to the side wall of the bonding head 11 through the first material area 13a, another set of opposite sides of the second material area 13b is directly connected to the side wall of the bonding head 11, and the sides of the first material area 13a that are not connected to the second material area 13b are directly connected to the side wall of the bonding head 11. When the cavity 13 is not pressurized, the first material area 13a is relatively small and is substantially flat. When the cavity 13 is pressurized (e.g., by blowing air), the area of ​​the first material area 13a increases and tilts downward, so that the second material area 13b connected to the first material area 13a protrudes downward. The second material area 13b is inclined in the second direction (e.g., Figure 4 The longitudinal cross-sectional shape on the bonding head 11 (as shown in the X direction in FIG) changes from a straight line when no pressure is applied to an arch shape. The present invention is not limited to this. In other embodiments, the lower surface of the bottom wall of the bonding head 11 may also adopt other structures, so that when a suitable pressure is applied to deform the cavity, the middle area of ​​the lower surface of the bottom wall of the bonding head 11 protrudes downward to a greater extent than the edge area, thereby causing the middle area of ​​the lower surface of the chip 21 to protrude downward to a greater extent than the edge area. During the bonding process between the chip 21 and the bonding object 31, by releasing the cavity pressure, after the bonding is completed, the lower surfaces of the bonding head 11 and the chip 21 return to a plane.

[0045] The embodiment of the present invention also includes a bonding method, wherein the bonding device used in the bonding method includes a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and a side wall of the bonding head. For example, the bonding device described in the embodiment of the present invention can be used, combined with Figures 2 to 5 , the bonding method comprises the following steps:

[0046] In the first step, the chip 21 to be bonded is adsorbed by the bottom wall of the bonding head 11, and moved to the upper surface of the bonding object 31 for alignment;

[0047] In the second step, pressure is applied to the cavity 13, so that the bottom wall of the bonding head 11 is deformed under the pressure, and the middle area of ​​the lower surface of the chip 21 is arched toward the bonding object 21 (for example, a substrate or another chip);

[0048] The third step is to make the chip 21 fit with the bonding object 31 , wherein the middle area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 before the edge area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 .

[0049] In the bonding method, after the first step and before the second step, the chip 21 can be first moved down to a position where it has not yet contacted the upper surface of the bonding object 31; then the second step is performed, and as the bottom wall of the bonding head 11 is deformed, the middle area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 or is located at a set distance from the upper surface of the bonding object 31, and then the pressure applied to the cavity 13 is stopped; and then the third step is performed to bond the chip 21 to be bonded with the bonding object 31. During the bonding process, the pressure in the cavity 13 can be gradually released so that after the bonding is completed, the lower surfaces of the bonding head 11 and the chip 21 are restored to a plane.

[0050] In the third step, when the chip 21 is bonded to the bonding object 31, since the middle area of ​​the lower surface of the chip 21 is arched toward the bonding object 31, the pressing speed can be controlled so that the middle area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 before the edge area. For example, after detecting that the middle area of ​​the lower surface of the chip 21 contacts the bonding object 31, wait for 1s to 2s, and then continue to press down, gradually releasing the vacuum at the edge of the chip 21, so that the bonding wave generated by the bonding of the chip 21 and the bonding object 31 gradually diffuses from the middle area of ​​the bonding surface to the periphery, and the formation of closed bubbles between the lower surface of the chip 21 and the upper surface of the bonding object 31 can be avoided.

[0051] In an embodiment of the present invention, the bonding device includes a bonding head 11 having a cavity 13, the bottom wall of the bonding head 11 is used to absorb the chip 21 to be bonded, and the lower surface of the absorbed chip 21 is bonded to the upper surface of a bonding object 31. Before bonding, pressure is applied to the cavity 13 surrounded by the bottom wall and side walls of the bonding head 11, so that the bottom wall of the bonding head 11 is deformed under the action of pressure, and the middle area of ​​the lower surface of the chip 21 absorbed by the bonding head 11 is arched toward the bonding object 31. When bonding, the middle area of ​​the lower surface of the chip 21 contacts the upper surface of the bonding object 31 before the edge area. Compared with the direct contact between the lower surface of the chip 21 and the bonding object 31, it is possible to avoid the formation of closed bubbles between the lower surface of the chip 21 and the upper surface of the bonding object 31, reduce the probability of void defects at the bonding surface, and improve the bonding quality. The bonding method adopts the above-mentioned bonding device, and when the chip 21 and the bonding object 31 are bonded together, the probability of void defects occurring at the bonding surface can be reduced, thereby improving the bonding quality.

[0052] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.

[0053] The above description is only a description of the preferred embodiment of the present invention, and is not any limitation on the scope of rights of the present invention. Any technical personnel in this field can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A bonding device, characterized in that: The invention comprises a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and side walls of the bonding head, the bottom wall of the bonding head is used for adsorbing a chip to be bonded, and bonding the lower surface of the adsorbed chip to the upper surface of a bonding object, wherein before the bonding is performed, pressure is applied to the cavity to deform the bottom wall of the bonding head under the action of pressure, and the middle area of ​​the lower surface of the chip is arched toward the bonding object, and when the bonding is performed, the middle area contacts the upper surface of the bonding object before the edge area of ​​the lower surface of the chip, and after the bonding is completed, the middle area and the edge area both contact the upper surface of the bonding object, and the lower surfaces of the bonding head and the chip return to a plane.

2. The bonding device according to claim 1, characterized in that Air pressure or hydraulic pressure is applied to the cavity.

3. The bonding device according to claim 1, characterized in that The bottom wall of the bonding head includes two first material areas arranged in a first direction and a second material area located between the two first material areas, the two first material areas are connected to the side wall of the bonding head, the second material area is connected to the side wall of the bonding head in the first direction through the two first material areas respectively, the second material area is directly connected to the side wall of the bonding head in a second direction perpendicular to the first direction, and the yield strength of the first material area is less than the yield strength of the second material area.

4. The bonding device according to claim 1, characterized in that The middle area of ​​the lower surface of the chip is arched with an amplitude of 1 μm to 10 μm.

5. The bonding device according to any one of claims 1 to 4, characterized in that: A plurality of adsorption holes are distributed on the lower surface of the bottom wall of the bonding head, and each of the adsorption holes is connected to a vacuum system to adsorb the chip.

6. The bonding device according to claim 5, characterized in that Each of the adsorption holes passes through the bottom wall of the bonding head and is communicated with a vacuum pipeline arranged in the cavity.

7. The bonding device according to claim 5, characterized in that The lower surface of the bottom wall of the bonding head is provided with a groove, and the plurality of adsorption holes are located in the groove.

8. The bonding device according to any one of claims 1 to 4, characterized in that: A suction cup is arranged on the lower surface of the bottom wall of the bonding head, and the suction cup is used for adsorbing the chip.

9. A bonding method, characterized in that: The bonding device used includes a bonding head having a cavity, wherein the cavity is surrounded by a bottom wall and a side wall of the bonding head, and the bonding method includes: Using the bottom wall of the bonding head to absorb the chip to be bonded, and moving it to the upper surface of the bonding object for alignment; Applying pressure to the cavity so that the bottom wall of the bonding head is deformed under the pressure and the middle area of ​​the lower surface of the chip is arched toward the bonding object; and, The chip is bonded to the bonding object, wherein the middle area contacts the upper surface of the bonding object before the edge area of ​​the lower surface of the chip. After the bonding is completed, both the middle area and the edge area contact the upper surface of the bonding object, and the lower surface of the bonding head and the chip returns to a plane.

10. The bonding method according to claim 9, characterized in that: Before the chip is bonded to the bonding object, the pressure applied to the cavity is stopped; during the bonding process of the chip and the bonding object, the pressure in the cavity is gradually released so that after the chip and the bonding object are bonded, the lower surfaces of the bonding head and the chip return to a plane.

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