Wafer bonding clamp

Abstract

The utility model discloses a wafer bonding clamp, which belongs to the technical field of semiconductor devices and comprises a clamp base body used for placing two wafers. The multiple clamping jaws are arranged on the clamp base body, the multiple clamping jaws are distributed in the circumferential direction of the edges of the wafers at equal intervals, and the two wafers are located between the clamp base body and the multiple clamping jaws; the multiple gaskets are arranged on the clamp base body, the multiple gaskets and the multiple clamping jaws are arranged in a one-to-one correspondence mode, the gaskets are located between the clamp base body and the clamping jaws, the gaskets and the clamping jaws are arranged in the axial direction of the wafers in an opposite mode, and the gaskets are located between the two wafers. According to the utility model, the stress uniformity of the wafer can be improved, and the interference of the force in the non-overlapping direction in the axial direction of the wafer is reduced; and the occurrence of the edge breakage problem of the wafer is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor devices, in particular to a wafer bonding fixture. Background Art

[0002] Wafer refers to the substrate (also called base) for manufacturing semiconductor transistors or integrated circuits. It is called a wafer because it is made of crystalline material and is round in shape. Before two wafers are temporarily bonded, wafer alignment needs to be completed. After alignment is completed, a fixture is used to load the two wafers to fix and maintain the relative position of the two wafers, and then transfer them to the bonding chamber for bonding. During bonding, a vacuum needs to be drawn between the two wafers to convert the relative overhead state of the two wafers into a bonded state. In this process, the role of the wafer fixture is particularly important.

[0003] The more commonly used wafer clamps in the industry include clamping mechanisms and isolation mechanisms. The clamping mechanism is used to clamp the wafer in position, and the isolation mechanism is used to isolate two wafers. The clamping mechanism applies a downward force to the edge of the wafer, and the isolation mechanism applies an upward force to the edge of the upper wafer. The upward force and the downward force do not correspond to each other in the axial direction of the wafer, which makes it easy for the wafer to have edge collapse and the entire wafer to break, causing losses to the back-end packaging factory.

[0004] To this end, a wafer bonding fixture is proposed. Utility Model Content

[0005] The utility model aims to provide a wafer bonding fixture, aiming to solve or improve at least one of the above technical problems.

[0006] To achieve the above-mentioned purpose, the utility model provides the following solution: The utility model provides a wafer bonding fixture, comprising:

[0007] A fixture base, used for placing two wafers;

[0008] A plurality of clamping jaws are arranged on the clamp base, the plurality of clamping jaws are distributed at equal intervals along the circumference of the wafer edge, and the two wafers are located between the clamp base and the plurality of clamping jaws;

[0009] A plurality of gaskets are arranged on the clamp base, the plurality of gaskets are arranged in one-to-one correspondence with the plurality of clamps, the gaskets are located between the clamp base and the clamps, the gaskets and the clamps are arranged opposite to each other in the axial direction of the wafer, and the gaskets are located between the two wafers.

[0010] Preferably, a plurality of first drive components are provided on the clamp base, and the plurality of first drive components are arranged and connected with the plurality of clamps in a one-to-one correspondence, and the first drive components can drive the clamps to rise and fall along the axial direction of the wafer, and can also drive the clamps to extend and retract along the radial direction of the wafer.

[0011] Preferably, a plurality of second driving components are provided on the clamp base, and the plurality of second driving components are arranged in one-to-one correspondence with and connected to the plurality of gaskets, and the second driving components drive the gaskets to extend and retract along the radial direction of the wafer.

[0012] Preferably, three clamps are provided, and the angle formed by two adjacent clamps and the center of the wafer is 120°.

[0013] The utility model discloses the following technical effects: two wafers are clamped between a clamp base and a clamping jaw, and a gasket is located between the two wafers for isolation, and the gasket and the clamping jaw are arranged opposite to each other in the axial direction of the wafer, so that the force points of the downward force and the upward force on the wafer coincide in the axial direction of the wafer, and in the process of static clamping and dynamic peeling of the gasket, the uniformity of the force is guaranteed, and the interference of the non-overlapping direction forces in the axial direction of the wafer is reduced; and the occurrence of the problem of chipping of the wafer edge is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0015] Figure 1 It is a structural schematic diagram of the utility model;

[0016] Figure 2 It is a schematic diagram of the positional relationship between two wafers, clamping jaws and gaskets before bonding in the utility model.

[0017] In the figure: 1. Clamping jaws; 2. Gasket; 3. Clamp base; 4. First wafer to be bonded; 5. Second wafer to be bonded. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] Reference Figure 1-Figure 2 The utility model provides a wafer bonding fixture, comprising:

[0021] A fixture base 3, used for placing two wafers;

[0022] The fixture base 3 is a hollow frame plate, and the material includes but is not limited to stainless steel. The two sides of the fixture base 3 have flatness and parallelism requirements, and the surface treatment is pickling and electrolytic polishing; the two wafers are respectively the first wafer to be bonded 4 and the second wafer to be bonded 5;

[0023] A plurality of clamping jaws 1 are arranged on a clamp base 3, and the plurality of clamping jaws 1 are distributed at equal intervals along the circumference of the wafer edge, and the two wafers are located between the clamp base 3 and the plurality of clamping jaws 1;

[0024] A plurality of gaskets 2 are arranged on a fixture base 3, the plurality of gaskets 2 are arranged one-to-one with the plurality of clamping jaws 1, the gaskets 2 are located between the fixture base 3 and the clamping jaws 1, the gaskets 2 and the clamping jaws 1 are arranged opposite to each other in the axial direction of the wafer, and the gaskets 2 are located between the two wafers;

[0025] The material and thickness of the gasket 2 are adjusted according to different processes, and the material includes but is not limited to stainless steel, copper, PEEK plastic, etc.;

[0026] The two wafers are clamped between the clamp base 3 and the clamping jaw 1, and the gasket 2 is located between the two wafers for isolation. The gasket 2 and the clamping jaw 1 are arranged opposite to each other in the axial direction of the wafer. Therefore, the force points of the downward force and the upward force on the wafer coincide with each other in the axial direction of the wafer. In this way, during the static clamping and dynamic peeling of the gasket, the uniformity of the force is guaranteed, and the interference of the non-overlapping direction is reduced; the occurrence of wafer edge collapse problems is reduced.

[0027] Further optimizing the scheme, a plurality of first drive components are arranged on the clamp base 3, and the plurality of first drive components are arranged and connected with the plurality of clamping jaws 1 in one-to-one correspondence, and the first drive components can drive the clamping jaws 1 to rise and fall along the axial direction of the wafer, and can also drive the clamping jaws 1 to extend and retract along the radial direction of the wafer;

[0028] Multiple clamps 1 act synchronously, and the lifting and extension of each clamp 1 move separately; when the clamp 1 retracts, it first rises away from the wafer surface and then retracts; this embodiment does not limit the specific structure of the first driving component, as long as it can drive the clamp 1 to lift and extend;

[0029] Further optimizing the scheme, a plurality of second driving components are arranged on the fixture base 3, and the plurality of second driving components are arranged and connected with the plurality of gaskets 2 in a one-to-one correspondence, and the second driving components drive the gaskets 2 to extend and retract along the radial direction of the wafer;

[0030] The present embodiment does not limit the specific structure of the second driving component, as long as it can drive the gasket 2 to extend and retract along the radial direction of the wafer; multiple gaskets 2 move synchronously.

[0031] According to a further optimization scheme, three clamping jaws 1 are provided, and the angle formed between two adjacent clamping jaws 1 and the center of the wafer is 120°; similarly, three gaskets 2 are provided, and the angle formed between two adjacent gaskets 2 and the center of the wafer is 120°;

[0032] During the processing, the wafer may be subjected to various forces, such as gravity, mechanical stress, etc. The equal spacing distribution helps to support the wafer more evenly and reduce deformation or damage caused by uneven force. Setting the angle to 120° so that the three force points are in an equilateral triangle support layout helps to improve the stability of the entire system. The 120° distributed fixture provides symmetrical support, which is very important for maintaining the roundness of the wafer and reducing deviations during processing. At the same time, it can simplify the operation path of the robot or automatic robotic arm and improve efficiency.

[0033] The gasket 2 is located between the two wafers before the bonding process of the two wafers, and plays the role of vacuum peeling between the two wafers. After vacuuming and before preparing for bonding, the gasket 2 is retracted and thus taken out from between the two wafers; the wafers are pressed by the clamp 1 to make the two wafers fit together, and then the subsequent bonding process and other auxiliary processes are carried out; the gasket 2 ensures the synchronization of actions during static vacuuming and dynamic peeling, and the clamp 1 ensures the uniformity of static force and dynamic force distribution during static clamping and dynamic clamping, and reduces the interference of non-radial effects; at the same time, the relative positions of the gasket 2 and the clamp 1 in the same group overlap in the vertical direction of the wafer, so that during static clamping and dynamic peeling of the gasket 2, the uniformity of force action is ensured while reducing the interference of effects in non-overlapping directions.

[0034] In an optional embodiment, the use process of the 12-inch wafer bonding fixture in the bonding equipment mainly includes placement, feeding, bonding, feeding, and material removal. The detailed interaction process with each module is as follows:

[0035] S1. Manually or mechanically take the fixture from the alignment machine and place it on the wafer stage of the bonding machine;

[0036] S2, the Y-axis cylinder of the wafer table is sent to the robot pick-up and placement position;

[0037] S3, the robot moves forward in X-axis and rises in Z-axis to take the fixture, and then rises to the highest position; at the same time, the wafer table is extended back;

[0038] S4, the gate valve of the vacuum chamber is opened, the X-axis of the robot is sent to the specified position, the Z-axis descends, the fixture is separated from the robot, and the material falls onto the lower pressure head; the robot is retracted and the gate valve is closed;

[0039] S5, evacuating the vacuum chamber;

[0040] S6, the upper pressure head descends, and at the same time, the peeling mechanism of the clamp is extended back by the mechanical device of the upper pressure head, and the two wafers are bonded;

[0041] S7, heating, pressurizing, completing the bonding process and other auxiliary processes.

[0042] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0043] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A wafer bonding fixture, characterized in that: include: A fixture base (3) for placing two wafers; A plurality of clamping jaws (1) are arranged on the clamp base (3), the plurality of clamping jaws (1) are distributed at equal intervals along the circumference of the edge of the wafer, and the two wafers are located between the clamp base (3) and the plurality of clamping jaws (1); A plurality of gaskets (2) are arranged on the clamp base (3), the plurality of gaskets (2) are arranged in one-to-one correspondence with the plurality of clamping jaws (1), the gasket (2) is located between the clamp base (3) and the clamping jaws (1), the gasket (2) and the clamping jaws (1) are arranged opposite to each other in the axial direction of the wafer, and the gasket (2) is located between the two wafers.

2. The wafer bonding fixture according to claim 1, characterized in that: A plurality of first drive components are arranged on the clamp base (3), and the plurality of first drive components are arranged in one-to-one correspondence with and connected to the plurality of clamping jaws (1). The first drive components can drive the clamping jaws (1) to rise and fall along the axial direction of the wafer, and can also drive the clamping jaws (1) to extend and retract along the radial direction of the wafer.

3. The wafer bonding fixture according to claim 1, characterized in that: A plurality of second drive components are arranged on the clamp base (3), and the plurality of second drive components are arranged in one-to-one correspondence with and connected to the plurality of gaskets (2), and the second drive components drive the gaskets (2) to expand and contract along the radial direction of the wafer.

4. The wafer bonding fixture according to claim 1, characterized in that: Three clamping jaws (1) are provided, and the angle formed between two adjacent clamping jaws (1) and the center of the wafer is 120°.

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