Wafer bonding machine and working method thereof

Abstract

The present invention relates to the technical field of wafer bonding, a wafer bonding machine and a working method thereof, comprising a fine-tuning mechanism, a small cylinder assembly, an oil cylinder assembly, a pressure assembly and a vacuum chamber; the fine-tuning mechanism is arranged above the small cylinder assembly and the upper part of the top block of the small cylinder assembly is movably embedded in a groove of the fine-tuning mechanism, the small cylinder assembly is arranged inside the oil cylinder assembly, the lower part of the top block of the small cylinder assembly is fixedly arranged on the upper part of the hydraulic cylinder piston of the oil cylinder assembly, the pressure assembly is arranged below the oil cylinder assembly, the lower part of the hydraulic cylinder piston of the oil cylinder assembly is sealed and fixedly arranged on the weighing sensor of the pressure assembly, and the lower part of the pressure assembly is sealed and fixedly arranged on the upper pressure head of the vacuum chamber, which solves the problems of easy breakage of wafers and low bonding accuracy during wafer bonding.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer bonding, and in particular to a wafer bonding machine and a working method thereof. Background Art

[0002] During the wafer processing, the wafer often warps up and produces a certain degree of warpage, which refers to the warping deformation of the center point of the wafer at the edge of the wafer. In the existing wafer bonding machines, most of them use direct pressure to bond the wafers. However, after the wafers are bonded to each other, it is not easy to control the moving distance of the pressure head, which can easily damage the wafer. Summary of the invention

[0003] The present invention provides a cavity for a bonding machine, which is used to solve the problem in the prior art that it is difficult to control the moving distance of a pressure head and wafers are easily damaged.

[0004] The present invention provides a wafer bonding machine, comprising a fine-tuning mechanism, a small cylinder assembly, an oil cylinder assembly, a pressure assembly and a vacuum chamber; the fine-tuning mechanism is arranged above the small cylinder assembly and the upper part of the top block of the small cylinder assembly is movably embedded in the groove of the fine-tuning mechanism, the small cylinder assembly is arranged inside the oil cylinder assembly, the lower part of the top block of the small cylinder assembly is fixedly arranged on the upper part of the hydraulic cylinder piston of the oil cylinder assembly, the pressure assembly is arranged below the oil cylinder assembly, the lower part of the hydraulic cylinder piston of the oil cylinder assembly is sealed and fixedly arranged on the weighing sensor of the pressure assembly, and the lower part of the pressure assembly is sealed and fixedly arranged on the upper pressure head of the vacuum chamber.

[0005] According to the wafer bonding machine of the present invention, the small cylinder assembly also includes a cylinder piston, a long rod seat and a first bellows; a cavity is arranged inside the lower part of the top block, the upper part of the cylinder piston is arranged in the cavity, the lower part of the cylinder piston is fixedly arranged at the central position inside the long rod seat, the long rod seat is sealed on the first bellows, a long rod is fixed outside the central position of the long rod seat, the long rod is arranged in the first bellows, and the cylinder piston moves up and down in the cavity.

[0006] According to the wafer bonding machine of the present invention, the small cylinder assembly further includes a first displacement sensor and a second displacement sensor; the first displacement sensor is used to detect the moving distance of the cylinder piston, and the second displacement sensor is used to detect the moving distance of the top block.

[0007] According to the wafer bonding machine of the present invention, a third boss is arranged at the lower part of the cylinder piston, a bolt is arranged closely on the third boss, the diameter of the third boss is smaller than the diameter of the bolt, and the long rod seat is arranged below the bolt.

[0008] According to the wafer bonding machine of the present invention, the fine-tuning mechanism includes an inner knob, an outer knob, a dial and a ruler; the dial is arranged below the outer knob, the inner knob is arranged at the center of the fine-tuning mechanism, the ruler is arranged close to the dial, and the bottom of the inner knob is arranged at the center of the groove of the fine-tuning mechanism and adjusts the top block.

[0009] According to the wafer bonding machine of the present invention, the pressure-applying assembly also includes a hydraulic piston connecting rod, a second bellows and a pressure head pressure ring; the weighing sensor is sealed and arranged on the upper part of the hydraulic piston connecting rod, a first boss is arranged on the lower part of the hydraulic piston connecting rod, the pressure head pressure ring is arranged closely below the first boss, the lower part of the second bellows is sealed and fixed on the vacuum chamber, and the upper part of the second bellows is fixed on the hydraulic piston connecting rod.

[0010] According to the wafer bonding machine of the present invention, the hydraulic piston connecting rod further comprises a second boss, the guide sleeve is arranged below the second boss, and the diameter of the second boss is equal to the diameter of the guide sleeve.

[0011] According to the wafer bonding machine of the present invention,

[0012] The guide sleeve is made of wear-resistant material.

[0013] The wafer bonding machine working method comprises:

[0014] Closing the vacuum chamber, evacuating the vacuum chamber, filling the vacuum chamber with inert gas and reducing atmosphere, and heating the workpiece;

[0015] The height of the long rod below the small cylinder assembly is adjusted by a fine-adjustment mechanism;

[0016] The long rod detects the wafer below, and the pressure component drives the upper pressure head to press and bond the workpiece, and the long rod retracts. Beneficial Effects

[0017] 1. The coarse adjustment mechanism, i.e. the outer knob, is used to precisely raise and lower the cylinder through the dial, while the fine adjustment mechanism, i.e. the inner knob, adjusts the length of the long rod of the small cylinder assembly.

[0018] The small cylinder assembly controls the displacement of the long rod by controlling the moving distance of the cylinder piston. Before bonding, due to gravity, the cylinder piston is at the bottom of the cylinder. During the bonding process, the long rod is retracted by the cylinder, and the retraction distance is greater than the bonding distance, ensuring that the long rod does not further exert pressure on the wafer to damage the wafer, thus protecting the wafer. At the same time, the other end of the piston is sealed by a bellows.

[0019] The purpose of setting up the long rod is that before bonding, the long rod first detects the wafer and positions and fixes the wafer, and the bonding head then applies pressure to bond the wafer. The long rod prevents the wafer from breaking and improves the bonding accuracy.

[0020] A third boss is arranged below the cylinder piston, the diameter of which is larger than the bolt diameter, and is used to clamp the bolt, so as to protect the cylinder piston when the cylinder piston moves too fast, and is suitable for fast cylinder pistons.

[0021] A guide sleeve is arranged below the second boss, and the diameter of the second boss is equal to the diameter of the guide sleeve. The guide sleeve protects the hydraulic piston connecting rod, and the second boss protects the guide sleeve to avoid wear and jamming of the hydraulic piston connecting rod.

[0022] 6. A first boss is arranged at the lower part of the hydraulic piston connecting rod, and the diameter of the first boss is smaller than the inner ring diameter of the pressure head pressure ring. A pressure head pressure ring is arranged closely below the first boss to limit the pressure head pressure ring, and is suitable for large bonding pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of the front view of the cavity of the wafer bonding machine;

[0025] Figure 2 is a schematic structural diagram of a cross-sectional view of a wafer bonding machine;

[0026] Figure 3 Schematic diagram of the fine-tuning mechanism

[0027] Figure 4 A structural schematic diagram of a cross-sectional view of a fine-tuning mechanism;

[0028] Figure 5 A structural schematic diagram of a three-dimensional diagram of a small cylinder assembly;

[0029] Figure 6 A structural schematic diagram of a cross-sectional view of a small cylinder assembly;

[0030] Figure 7 A structural schematic diagram of a three-dimensional diagram of a cylinder piston;

[0031] Figure 8 A structural schematic diagram of a cross-sectional view of an oil cylinder assembly;

[0032] Fig. 9It is a structural schematic diagram of a three-dimensional diagram of a pressure-applying component;

[0033] Fig.10 A schematic structural diagram of a cross-sectional view of a pressure-applying component;

[0034] Figure numerals: 1. fine-tuning mechanism; 2. small cylinder assembly; 3. oil cylinder assembly; 4. pressure-applying assembly; 5. long rod; 6. vacuum chamber; 11. inner knob; 12. outer knob; 13. dial; 14. scale; 21. top block; 22. cylinder piston; 23. second displacement sensor; 24. long rod seat; 25. first bellows; 26. third boss; 31. hydraulic cylinder piston; 32. hydraulic cylinder; 41. weighing sensor; 42. hydraulic piston connecting rod; 43. second bellows; 44. guide sleeve; 45. pressure head pressure ring; 46. first boss; 47. second boss. DETAILED DESCRIPTION

[0035] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0036] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0037] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0038] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0039] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0040] Combine the following Figure 1-10 A wafer bonding machine according to an embodiment of the present invention is described, comprising a fine-tuning mechanism 1, a small cylinder assembly 2, an oil cylinder assembly 3, a pressure assembly 4 and a vacuum chamber 6; the fine-tuning mechanism 1 is arranged above the small cylinder assembly 2 and the upper part of the top block 21 of the small cylinder assembly 2 is movably embedded in the groove of the fine-tuning mechanism 1, and the top block 21 of the small cylinder assembly 2 is moved up and down in the groove of the fine-tuning mechanism 1 by the inner knob 11 and the outer knob 12 of the fine-tuning mechanism 1 to adjust the height.

[0041] The small cylinder assembly 2 is arranged inside the oil cylinder assembly 3, and the hydraulic cylinder piston 31 is arranged inside the hydraulic cylinder 32. Two hollow cavities are arranged inside the hydraulic cylinder 32. The lower hollow cavity is longer than the upper hollow cavity. The upper hollow cavity limits the moving distance of the hydraulic cylinder piston 31, thereby protecting the wafer bonding machine. The lower part of the top block 21 of the small cylinder assembly 2 is fixedly arranged on the upper part of the hydraulic cylinder piston 31 of the oil cylinder assembly 3. The pressure assembly 4 is arranged below the oil cylinder assembly 3. The lower part of the hydraulic cylinder piston 31 of the oil cylinder assembly 3 is sealed and fixedly arranged on the weighing sensor 41 of the pressure assembly 4. The weighing sensor 41 accurately calculates the pressure to achieve accurate control of the bonding force, which is not easy to damage the wafer during bonding, and improves the bonding quality, thereby improving the product quality. The lower part of the pressure assembly 4 is sealed and fixedly arranged on the upper pressure head of the vacuum chamber 6.

[0042] The fine-tuning mechanism 1 includes an inner knob 11, an outer knob 12, a dial 13 and a scale 14; the dial 13 is arranged below the outer knob 12, the inner knob 11 is arranged at the center of the fine-tuning mechanism 1, the scale 14 is arranged close to the dial 13, the inner knob 11 is arranged below the center of the groove of the fine-tuning mechanism 1 and adjusts the top block 21, and when the inner knob 11 is adjusted downward, the inner knob 11 presses the top block 21 to move downward. The outer knob 12 adjusts the height through the dial 13 and the scale 14.

[0043] The pressure assembly 4 also includes a hydraulic piston connecting rod 42, a second bellows 43 and a pressure head pressure ring 45; the weighing sensor 41 is sealed and arranged on the upper part of the hydraulic piston connecting rod 42, a first boss 46 is arranged on the lower part of the hydraulic piston connecting rod 42, a pressure head pressure ring 45 is arranged closely below the first boss 46, the lower part of the second bellows 43 is sealed and fixed on the vacuum chamber 6, and the upper part of the second bellows 43 is fixed on the hydraulic piston connecting rod 42. A first boss 46 is arranged on the lower part of the hydraulic piston connecting rod 42, and the diameter of the first boss 46 is smaller than the inner ring diameter of the pressure head pressure ring 45. The pressure head pressure ring 45 is arranged closely below the first boss 46, which has a limiting effect on the pressure head pressure ring 45 and is suitable for large bonding pressure. The prior art uses an electric cylinder, and the bonding pressure is relatively small. The vacuum chamber 6 includes an upper pressure head, a wafer clamp assembly and a lower pressure head. The vacuum chamber for wafer bonding of the prior art can be used.

[0044] The invention realizes bonding by filling reducing or inert gas under vacuum state through the detection function of the long rod 5.

[0045] In this embodiment, the small cylinder assembly 2 also includes a cylinder piston 22, a long rod seat 24 and a first bellows 25; a cavity is provided inside the lower part of the top block 21, and the upper part of the cylinder piston 22 is provided in the cavity. The cylinder piston 22 moves up and down in the cavity. Therefore, when bonding, the long rod 5 retracts and the cylinder piston 22 moves upward in the cavity, reducing the risk of the long rod 5 crushing the wafer. The lower part of the cylinder piston 22 is fixedly provided at the central position inside the long rod seat 24, and the long rod seat 24 is sealed on the first bellows 25. The long rod 5 is fixed outside the central position of the long rod seat 24. Specifically, the long rod seat 24 is hollowed out as a cylinder at the central position, and the inner and outer sides of the cylinder are threaded. The upper end of the long rod seat 24 is a fixed flange, which is sealed and connected to the first bellows 25 through the fixed flange of the long rod seat 24. The long rod 5 is provided in the first bellows 25.

[0046] In the above embodiment, the small cylinder assembly 2 further includes a first displacement sensor and a second displacement sensor 23; the first displacement sensor is used to detect the moving distance of the cylinder piston, and the second displacement sensor 23 is used to detect the moving distance of the top block. A distance measuring sensor is provided on the upper pressure head of the vacuum chamber 6 to measure the distance between the upper pressure head and the wafer, and the moving distance of the pressure assembly 4 is controlled by the distance.

[0047] In this embodiment, a third boss 26 is provided at the lower part of the cylinder piston 22, a bolt is closely provided at the third boss 26, the diameter of the third boss 26 is smaller than the diameter of the bolt, and a long rod seat 24 is provided below the bolt. The lower part of the cylinder piston 22 is directly connected with the long rod seat 24 by a first thread, and the bolt is connected with the cylinder piston 22 by a second thread, which ensures the connection reliability between the cylinder piston 22 and the long rod seat 24, and the third boss 26 limits the bolt by a boss, which is suitable for a fast cylinder piston 22.

[0048] In this embodiment, the hydraulic piston connecting rod 42 further includes a second boss 47, a guide sleeve 44 is arranged below the second boss 47, and the diameter of the second boss 47 is equal to the diameter of the guide sleeve 44. The guide sleeve 44 is arranged below the second boss 47, and the diameter of the second boss 47 is equal to the diameter of the guide sleeve 44. The guide sleeve 44 protects the hydraulic piston connecting rod 42, and the second boss 47 protects the guide sleeve 44 to prevent the hydraulic piston connecting rod 42 from being worn and stuck.

[0049] The guide sleeve 44 is made of wear-resistant material.

[0050] Wafer bonding machine working method, including:

[0051] The vacuum chamber is closed, evacuated, filled with inert gas and reducing atmosphere, and the workpiece is heated;

[0052] The height of the long rod below the small cylinder assembly is adjusted by a fine-adjustment mechanism;

[0053] The long rod 5 detects the wafer below, the pressure assembly 4 drives the upper pressure head to press and bond the workpiece, and the long rod 5 retracts.

[0054] The purpose of setting the long rod 5 is that before bonding, the long rod 5 first contacts the wafer and positions and fixes the wafer, and then the bonding head applies pressure to bond the wafer, and the long rod 5 retracts, so that the long rod 5 prevents the wafer from breaking and improves the bonding accuracy.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wafer bonding machine, characterized in that: It comprises a fine-tuning mechanism, a small cylinder assembly, an oil cylinder assembly, a pressure assembly and a vacuum chamber; the fine-tuning mechanism is arranged above the small cylinder assembly and the upper part of the top block of the small cylinder assembly is movably embedded in the groove of the fine-tuning mechanism, the small cylinder assembly is arranged inside the oil cylinder assembly, the lower part of the top block of the small cylinder assembly is fixedly arranged on the upper part of the hydraulic cylinder piston of the oil cylinder assembly, the pressure assembly is arranged below the oil cylinder assembly, the lower part of the hydraulic cylinder piston of the oil cylinder assembly is sealed and fixedly arranged on the weighing sensor of the pressure assembly, and the lower part of the pressure assembly is sealed and fixedly arranged on the upper pressure head of the vacuum chamber; The small cylinder assembly also includes a cylinder piston, a long rod seat and a first bellows; a cavity is arranged inside the lower part of the top block, the upper part of the cylinder piston is arranged in the cavity, the lower part of the cylinder piston is fixedly arranged at the central position inside the long rod seat, the long rod seat is sealed on the first bellows, a long rod is fixed outside the central position of the long rod seat, the long rod is arranged in the first bellows, and the cylinder piston moves up and down in the cavity.

2. The wafer bonding machine according to claim 1, characterized in that: The small cylinder assembly further includes a first displacement sensor and a second displacement sensor; the first displacement sensor is used to detect the moving distance of the cylinder piston, and the second displacement sensor is used to detect the moving distance of the top block.

3. The wafer bonding machine according to claim 1, characterized in that: A third boss is arranged at the lower part of the cylinder piston, a bolt is arranged closely on the third boss, the diameter of the third boss is smaller than the diameter of the bolt, and the long rod seat is arranged below the bolt.

4. The wafer bonding machine according to claim 1, characterized in that: The fine-tuning mechanism includes an inner knob, an outer knob, a dial and a scale; the dial is arranged below the outer knob, the inner knob is arranged at the center of the fine-tuning mechanism, the scale is arranged close to the dial, and the lower part of the inner knob is arranged at the center of the groove of the fine-tuning mechanism and adjusts the top block.

5. The wafer bonding machine according to claim 1, characterized in that: The pressure-applying assembly also includes a hydraulic piston connecting rod, a second bellows and a pressure head pressure ring; the weighing sensor is sealed and arranged on the upper part of the hydraulic piston connecting rod, a first boss is arranged on the lower part of the hydraulic piston connecting rod, the pressure head pressure ring is arranged closely below the first boss, the lower part of the second bellows is sealed and fixed on the vacuum chamber, and the upper part of the second bellows is fixed on the hydraulic piston connecting rod.

6. The wafer bonding machine according to claim 5, characterized in that: The hydraulic piston connecting rod further comprises a second boss and a guide sleeve. The guide sleeve is arranged below the second boss. The diameter of the second boss is equal to the diameter of the guide sleeve.

7. The wafer bonding machine according to claim 6, characterized in that: The guide sleeve is made of wear-resistant material.

8. A wafer bonding machine working method according to any one of claims 1 to 7, characterized in that: include: Closing the vacuum chamber, evacuating the vacuum chamber, filling the vacuum chamber with inert gas and reducing atmosphere, and heating the workpiece; The height of the long rod below the small cylinder assembly is adjusted by a fine-adjustment mechanism; The long rod detects the wafer below, and the pressure component drives the upper pressure head to press and bond the workpiece, and the long rod retracts.

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