High-precision wafer lifting mechanism

Abstract

The invention relates to the technical field of wafer bonding, in particular to a high-precision wafer lifting mechanism, and mainly solves the technical problem of low wafer placement precision caused by large starting and stopping inertia of a lifting mechanism during wafer loading and unloading in the prior art. The high-precision wafer lifting mechanism comprises a fixed frame, a wafer chuck, a fixed batten, a movable batten, a lifting driving piece, a connecting frame, an ejector pin, a damping assembly and a sensor assembly, on one hand, the damping assembly is arranged between a fixed part and a lifting part of the lifting driving piece, and the damping assembly can reduce the starting and stopping inertia of the lifting driving piece; therefore, the deviation of the wafer can be effectively avoided, and the placement precision of the wafer is ensured. On the other hand, the operation precision of the lifting driving piece is controlled through cooperation of a photoelectric sensor and a sensor piece, and the operation precision is guaranteed; the cooperation of the two aspects ensures high precision of wafer placement.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer bonding, and particularly to a high-precision wafer lifting mechanism. Background Art

[0002] Wafer bonding is to tightly bond two polished homogeneous or heterogeneous wafers through chemical and physical actions. After wafer bonding, the atoms at the interface react under the action of external forces to form covalent bonds and integrate into one body, and the bonding interface reaches a specific bonding strength, which is a technical process of tightly bonding substrates or patterned wafers for semiconductor composite substrate preparation and high-precision wafer interconnection. When wafer bonding, the manipulator needs to cooperate with the lifting mechanism to complete the loading or unloading of the wafer, that is: during loading, first the manipulator holds the wafer above the wafer chuck, then the lifting mechanism jacks up the wafer, then the manipulator withdraws, and finally the lifting mechanism descends to make the wafer fall onto the wafer chuck to complete loading; during unloading, first the lifting mechanism jacks up the wafer, then the manipulator moves empty to between the wafer chuck and the wafer, then the lifting mechanism descends to make the wafer fall onto the manipulator, and finally the manipulator holds the wafer and withdraws to complete unloading.

[0003] The existing lifting mechanisms are generally driven by common lifting driving parts, with large starting and stopping inertia, which easily causes the offset of the wafer and low wafer placement accuracy. Summary of the Invention

[0004] To overcome the technical defect of low wafer placement accuracy caused by large starting and stopping inertia of the lifting mechanism during wafer loading and unloading, the present invention provides a high-precision wafer lifting mechanism.

[0005] The high-precision wafer lifting mechanism provided by the present invention includes: A fixed frame; A wafer chuck, which is fixed at the top of the fixed frame and arranged horizontally; A fixed strip board, which is fixed on one side of the fixed frame; A movable strip board, which is installed on one side of the fixed frame and can slide vertically, and the movable strip board is located above the fixed strip board; A lifting driving part, whose fixed part is fixed on the fixed strip board and the lifting part is fixedly connected with the movable strip board; A connecting frame, which is fixed on the movable strip board, and at least three ejector pins arranged upward are provided on the connecting frame, and avoidance holes are opened at the positions of the wafer chuck corresponding to the ejector pins, and all the ejector pins cooperate to realize the lifting of the wafer; A damping assembly, which has at least one set, and the damping assembly includes two spring support columns and a tension spring, the two spring support columns are respectively fixed on the fixed strip board and the movable strip board, and the two ends of the tension spring are respectively connected to the two spring support columns; A sensor assembly, comprising a photoelectric sensor and a sensor sheet, wherein the photoelectric sensor is fixed on the movable strip board, the sensor sheet is fixed on the fixed frame, and the photoelectric sensor cooperates with the sensor sheet to control the lifting position of the movable strip board.

[0006] Optionally, the wafer chuck is an electrostatic chuck.

[0007] Optionally, the lifting drive is an electric push rod.

[0008] Optionally, the connecting frame includes: A spacer block, which is fixed on the movable strip board and fixedly connected to the lifting part of the lifting drive; An L-shaped plate, which consists of a horizontal plate and a vertical plate, and the vertical plate is fixed on the spacer block; A support frame, which includes a main body part and at least three mounting ears distributed on the edge of the main body part. The main body part is fixed on the horizontal plate. The mounting ears correspond to the thimbles one by one and include two clamping bars and a locking bolt vertically inserted through the two clamping bars. A gap is formed between the two clamping bars, and an assembly hole adapted to the thimble is provided in the middle of the length direction of the gap. The bottom of the thimble is inserted into the assembly hole and clamped by the locking bolt.

[0009] Optionally, there are three thimbles, and the mounting ears are provided with three corresponding to the thimbles.

[0010] The technical solution provided by the present invention has the following advantages compared with the prior art: The high-precision wafer lifting mechanism provided by the present invention, on the one hand, is provided with a damping component between the fixed part and the lifting part of the lifting drive. The damping component can reduce the start-stop inertia of the lifting drive, thereby effectively avoiding the offset of the wafer and ensuring the placement accuracy of the wafer; on the other hand, the running accuracy of the lifting drive is controlled through the cooperation of the photoelectric sensor and the sensor sheet to ensure its running accuracy; the two aspects cooperate to ensure the high precision of wafer placement. Description of the Drawings

[0011] The drawings here are incorporated into the specification and form a part of this specification, showing the embodiments in line with the present invention, and are used together with the specification to explain the principles of the present invention.

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0013] Figure 1It shows a schematic diagram of the overall structure of the high-precision wafer lifting mechanism in the embodiment of the present invention; Figure 2 It shows a schematic diagram of the movable strip board and its attached structures in the embodiment of the present invention.

[0014] In the figure: 1. Fixed frame; 2. Wafer chuck; 21. Avoidance hole; 3. Fixed strip board; 4. Movable strip board; 5. Lifting driving member; 6. Connecting frame; 61. Cushion block; 62. L-shaped plate; 63. Support frame; 631. Main body part; 632. Mounting ear; 6321. Clamping strip; 6322. Locking bolt; 7. Thimble; 8. Damping assembly; 81. Spring support pillar; 82. Tensile spring; 9. Sensor assembly; 91. Photoelectric sensor; 92. Sensor piece. Specific embodiments

[0015] In order to more clearly understand the above objects, features and advantages of the present invention, the solution of the present invention will be further described below. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0016] It should be noted that, unless otherwise clearly defined and limited, the terms "installation", "connection" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

[0017] Many specific details are set forth in the following description in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only a part of the embodiments of the present invention, rather than all the embodiments.

[0018] The specific embodiments of the present invention will be described in detail below with reference to the drawings.

[0019] This embodiment provides a high-precision wafer lifting mechanism, including: a fixed frame 1; a wafer chuck 2, which is fixed at the top of the fixed frame 1 and arranged horizontally; a fixed strip plate 3, which is fixed on one side of the fixed frame 1; a movable strip plate 4, which is installed on one side of the fixed frame 1 and can slide in the vertical direction, and the movable strip plate 4 is located above the fixed strip plate 3; a lifting driving member 5, whose fixed part is fixed on the fixed strip plate 3 and the lifting part is fixedly connected to the movable strip plate 4; a connecting frame 6, which is fixed on the movable strip plate 4, and at least three ejector pins 7 arranged upward are provided on the connecting frame 6. Avoidance holes 21 are opened at the positions of the wafer chuck 2 corresponding to the ejector pins 7, and all the ejector pins 7 cooperate to realize the lifting of the wafer; a damping assembly 8, which has at least one set. The damping assembly 8 includes two tension spring supports 81 and a tension spring 82. The two tension spring supports 81 are respectively fixed on the fixed strip plate 3 and the movable strip plate 4, and the two ends of the tension spring 82 are respectively connected to the two tension spring supports 81; a sensor assembly 9, which includes a photoelectric sensor 91 and a sensor piece 92. The photoelectric sensor 91 is fixed on the movable strip plate 4, and the sensor piece 92 is fixed on the fixed frame 1. The photoelectric sensor 91 cooperates with the sensor piece 92 to control the lifting position of the movable strip plate 4. During operation, the lifting part of the lifting driving member 5 rises to drive the movable strip plate 4 to rise, thereby driving the connecting frame 6 and the ejector pins 7 to rise. The ejector pins 7 penetrate through the avoidance holes 21 of the wafer chuck 2 and finally lift the wafer.

[0020] Specifically, the fixed frame 1 includes a top plate, a bottom plate and four columns connected between the top plate and the bottom plate. The four columns are distributed in a rectangle, and both the movable strip plate 4 and the fixed strip plate 3 are installed on the same group of two adjacent columns.

[0021] Specifically, the wafer chuck 2 is an electrostatic chuck. When the wafer falls onto the electrostatic chuck, it is electrostatically adsorbed, which can effectively avoid the movement and displacement of the wafer and further ensure the placement accuracy of the wafer.

[0022] Specifically, the lifting driving member 5 is an electric push rod. The electric push rod has a high precision, which is more conducive to ensuring the placement accuracy of the wafer.

[0023] Specifically, the connecting frame 6 includes: a cushion block 61, which is fixed on the movable strip 4 and fixedly connected to the lifting part of the lifting driving member 5; an L-shaped plate 62, which consists of a horizontal plate and a vertical plate, and the vertical plate is fixed on the cushion block 61; a support frame 63, which includes a main body part 631 and at least three mounting ears 632 distributed on the edge of the main body part 631. The main body part 631 is fixed on the horizontal plate. The mounting ears 632 correspond to the ejector pins 7 one by one and include two clamping strips 6321 and a locking bolt 6322 vertically inserted through the two clamping strips 6321. A gap is formed between the two clamping strips 6321, and an assembly hole adapted to the ejector pin 7 is provided in the middle of the length direction of the gap. The bottom of the ejector pin 7 is inserted into the assembly hole and clamped by the locking bolt 6322. The connecting frame 6 adopts a split design, which is more conducive to installation and disassembly; the mounting ear 632 uses two clamping strips 6321 in cooperation with the locking bolt 6322 to clamp the ejector pin 7 to complete the assembly, which is more convenient for installation, more firm in assembly, and more conducive to the height adjustment of the ejector pin 7.

[0024] More specifically, there are three ejector pins 7, and the mounting ears 632 are provided with three corresponding to the ejector pins 7. The three ejector pins 7 can stably support the wafer.

[0025] The working principle of the high-precision wafer lifting mechanism of this embodiment is as follows: During wafer loading, first, the manipulator carries the wafer above the wafer chuck 2, and then the lifting driving member 5 lifts the wafer. The damping assembly 8 applies resistance during the operation of the lifting driving member 5 to reduce the start-stop inertia of the lifting driving member 5. The photoelectric sensor 91 and the sensor piece 92 cooperate to control the stroke of the lifting driving member 5. Then the manipulator withdraws. Finally, the lifting driving member 5 descends to make the wafer fall onto the wafer chuck 2 to complete wafer loading; during wafer unloading, first, the lifting driving member 5 lifts the wafer, then the manipulator moves empty to between the wafer chuck 2 and the wafer, then the lifting driving member 5 descends to make the wafer fall onto the manipulator, and finally the manipulator carries the wafer and withdraws to complete wafer unloading.

[0026] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Although the foregoing embodiments have been described in detail, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the foregoing embodiments, and they should all be covered by the protection scope of the claims.

Claims

1. A high-precision wafer lifting mechanism, characterized in that: include: Fixed frame (1); A wafer chuck (2), which is fixed on the top of the fixing frame (1) and arranged horizontally; A fixed strip (3) fixed to one side of the fixed frame (1); A movable strip (4) which is mounted on one side of the fixed frame (1) and can slide in a vertical direction, the movable strip (4) being located above the fixed strip (3); A lifting drive member (5), wherein a fixed portion is fixed on the fixed strip plate (3) and a lifting portion is fixedly connected to the movable strip plate (4); A connecting frame (6) fixed on the movable strip plate (4), the connecting frame (6) being provided with at least three ejector pins (7) arranged upward, a position of the wafer chuck (2) corresponding to the ejector pins (7) being provided with an avoidance hole (21), and all the ejector pins (7) being used in cooperation to achieve the lifting and lowering of the wafer; A damping assembly (8), comprising at least one set, the damping assembly (8) comprising two tension spring struts (81) and a tension spring (82), the two tension spring struts (81) being respectively fixed to the fixed strip plate (3) and the movable strip plate (4), and the two ends of the tension spring (82) being respectively connected to the two tension spring struts (81); A sensor assembly (9) comprising a photoelectric sensor (91) and a sensor sheet (92); the photoelectric sensor (91) is fixed on the movable strip (4); the sensor sheet (92) is fixed on the fixed frame (1); the photoelectric sensor (91) cooperates with the sensor sheet (92) to control the lifting position of the movable strip (4).

2. The high-precision wafer lifting mechanism according to claim 1, characterized in that: The wafer chuck (2) is an electrostatic chuck.

3. The high-precision wafer lifting mechanism according to claim 1, characterized in that: The lifting drive component (5) is an electric push rod.

4. The high-precision wafer lifting mechanism according to claim 1, characterized in that: The connecting frame (6) comprises: A cushion block (61) fixed on the movable strip plate (4) and fixedly connected to the lifting portion of the lifting drive member (5); An L-shaped plate (62) consisting of a horizontal plate and a vertical plate, wherein the vertical plate is fixed on the spacer block (61); A support frame (63) comprises a main body (631) and at least three mounting ears (632) distributed on the edge of the main body (631), wherein the main body (631) is fixed to the transverse plate, the mounting ears (632) correspond to the ejector pins (7) one by one and comprise two clamping strips (6321) and locking bolts (6322) vertically inserted into the two clamping strips (6321), a gap is formed between the two clamping strips (6321) and an assembly hole adapted to the ejector pin (7) is provided in the middle of the gap in the length direction, and the bottom of the ejector pin (7) is inserted into the assembly hole and clamped by the locking bolts (6322).

5. The high-precision wafer lifting mechanism according to claim 4, characterized in that: Three ejector pins (7) are provided, and three mounting ears (632) are provided corresponding to the ejector pins (7).

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