Wafer position adjustment mechanism and adjustment method

Abstract

The application relates to the technical field of semiconductor processing, in particular to a wafer position adjusting mechanism and adjusting method. The wafer position adjusting mechanism comprises a lower bearing table body, the lower part of a lower chuck passes through the lower bearing table body and is installed on a translation rotation assembly located below the lower bearing table body; the upper part of the lower chuck is located above the lower bearing table body. The wafer position adjusting mechanism cancels the movable upper moving table and other mechanisms in the prior art, takes the upper bearing table as a reference, aligns the lower bearing table to the upper bearing table, integrates the translation and rotation shafts on the lower bearing table, and makes the lower chuck have the translation and rotation functions, so that the adjusting precision is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing technology, and in particular to a wafer position adjustment mechanism and adjustment method. Background Technology

[0002] In wafer hybrid bonding equipment, the upper and lower wafers need to be aligned, which requires adjusting the relative positions of the upper and lower support stages that carry the wafers, including translation and rotation. In existing technology, the upper and lower support stages are respectively mounted on upper and lower motion stages (see...). Figure 5 (where 100 is the base, 101 is the upper motion stage, 102 is the lower motion stage, 103 is the upper support stage, and 104 is the lower support stage). The lower motion stage does not have translational and rotational degrees of freedom, while the upper motion stage has translational degrees of freedom X and Y, and can fit rotation through the translation axes X1, Y1, and Y2, thereby driving the upper support stage to complete translation and rotation, and completing the alignment of the upper and lower wafers.

[0003] In this mechanism, the upper motion table needs to have translational and rotational degrees of freedom. It also needs a structure that can move relative to the base and remain relatively stationary when stationary. This part of the structure is typically made of marble and is quite heavy. Secondly, the translation of the upper motion table can be accomplished by drive mechanisms in the X and Y directions, but rotational motion requires simultaneous movement of both drives in the two directions. When a rotation angle is required, the displacement relationship between the angle and X1, Y1, and Y2 is difficult to calculate, and the displacements of X1, Y1, and Y2 are also affected by the position of the rotation axis, making the adjustment process extremely complex. Summary of the Invention

[0004] The purpose of this invention is to provide a wafer position adjustment mechanism and adjustment method.

[0005] To address the aforementioned technical problems, this application provides the following technical solution:

[0006] A wafer positioning adjustment mechanism includes a lower support stage body, with the lower part of a lower suction cup passing through the lower support stage body and mounted on a translational rotation assembly located below the lower support stage body; the upper part of the lower suction cup is located above the lower support stage body.

[0007] The lower support platform body has a set of air bearings on both sides of its lower surface, a Y-axis linear motor in the middle of its side, and at least one adsorption area in the middle of the air bearing.

[0008] The lower support platform body has two parallel linear guide rails installed on its lower surface. The translation and rotation assembly is installed below the lower support platform body via the two linear guide rails, and the linear guide rails provide X-axis guidance for the translation and rotation assembly.

[0009] The lower surface of the lower support platform is also equipped with an X-axis motor, which can be a piezoelectric ceramic motor or a linear motor, preferably a piezoelectric ceramic motor. A linear motor increases size and weight, requires control to maintain stillness, and the positioning ripple of a stationary linear motor increases the error. Additionally, the lower surface of the lower support platform is also equipped with a reading head for reading X-axis motion parameters.

[0010] The translation and rotation assembly includes a base plate. The lower suction cup is mounted on the translation and rotation assembly via a collar. The upper surface of the outer ring of the collar is fixed to the lower surface of the base plate. The inner ring of the collar is fixedly connected to the lower part of the lower suction cup. The lower suction cup can rotate around the axis of the collar. A ceramic ring and a circular grating are sequentially mounted on the lower part of the lower suction cup. The ceramic ring and the circular grating are located below the collar. A rotating reading head for detecting the rotation angle is mounted on one side of the circular grating.

[0011] At least one rotary motor for driving the lower suction cup to rotate is mounted below the substrate. The rotary motor is a piezoelectric ceramic motor or a torque motor, preferably a piezoelectric ceramic motor.

[0012] The substrate has an X-axis grating ruler and an X-axis ceramic plate mounted on its side.

[0013] The translation and rotation assembly and the lower suction cup are mounted on a linear guide rail below the lower support platform body, and the contacts of the X-axis motor are pressed against the X-axis ceramic plate.

[0014] The adjustment method of the wafer position adjustment mechanism of the present invention is as follows: After the measurement system detects the deviation between the upper and lower wafers, the required rotation and movement of the lower suction cup can be obtained. The lower suction cup first completes the angle deviation compensation through its own rotational degree of freedom. Then, the rotary motor is de-energized, the motor contacts press against the ceramic ring, and the rotational degree of freedom is restricted. Then, the X-axis deviation compensation is completed through the X-axis stroke of the lower suction cup. Then, the X-axis motor is de-energized, the motor contacts press against the X-axis ceramic sheet, and the X-axis degree of freedom is restricted. Finally, the Y-axis deviation compensation is completed through the Y-axis degree of freedom of the lower support stage body. Then, the lower support stage disconnects the air flotation and is adsorbed onto the lower moving stage, and the compensation process ends.

[0015] The wafer position adjustment mechanism of this invention transforms rotational motion from multi-axis fitting to direct rotation, determining the unique position of the rotation axis—that is, the rotation axis is always coaxial with the lower suction cup—and directly measuring the rotation angle, eliminating complex calculations and detection. Once the rotation angle is compensated, the current position can be maintained without enabling control, eliminating minor errors caused by the tuning process in control. Similarly, after X-axis position compensation, the lower suction cup remains stationary in the adjusted position. The piezoelectric ceramic motor can achieve extremely small step sizes, and combined with a high-resolution grating ruler, small angle and small displacement adjustments can be completed. Furthermore, since the lower support stage itself can achieve X, Y, and rotational degrees of freedom, a movable marble motion stage (i.e., the upper motion stage in the prior art, such as...) is no longer needed. Figure 5 It only requires a fixed air-bearing guide rail base for the upper support platform, which can reduce a significant portion of the overall weight of the machine.

[0016] Compared with the prior art, the wafer position adjustment mechanism and adjustment method of the present invention have at least the following beneficial effects:

[0017] The wafer position adjustment mechanism of this invention eliminates the movable upper stage and other mechanisms in the prior art. With the upper support stage as the reference, the lower support stage is aligned with the upper support stage, and the translation and rotation axes are integrated on the lower support stage, so that the lower suction cup has translation and rotation functions, which greatly improves the adjustment accuracy.

[0018] The wafer position adjustment mechanism and adjustment method of the present invention will be further described below with reference to the accompanying drawings. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the wafer position adjustment mechanism of the present invention;

[0020] Figure 2 This is another schematic diagram of the wafer position adjustment mechanism of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the lower support platform.

[0022] Figure 4 This is a schematic diagram of the lower suction cup and translation / rotation assembly (the lower support platform body is omitted in the diagram);

[0023] Figure 5 This is a schematic diagram of a wafer positioning mechanism in the prior art.

[0024] Among them, 1-lower support platform body, 2-lower suction cup, 3-translation and rotation assembly;

[0025] 11-Y-axis linear motor, 12-X-axis motor, 13-reading head, 14-air bearing, 15-linear guide rail, 16-adsorption area;

[0026] 21-Substrate, 22-X-direction grating ruler, 23-X-direction ceramic sheet, 24-Collar, 25-Rotary motor, 26-Ceramic ring, 27-Rotary reading head, 28-Circular grating;

[0027] 100-Base, 101-Upper moving platform, 102-Lower moving platform, 103-Upper bearing platform, 104-Lower bearing platform. Detailed Implementation

[0028] like Figure 1-2 As shown, a wafer position adjustment mechanism includes a lower support platform body 1, the lower part of a lower suction cup 2 passing through the lower support platform body 1 and mounted on a translation and rotation assembly 3 located below the lower support platform body 1; the upper part of the lower suction cup 2 is located above the lower support platform body 1.

[0029] like Figure 3 As shown, a set of air bearings 14 are respectively provided on both sides of the lower surface of the lower support platform body 1. A Y-axis linear motor 11 is installed in the middle of the side of the lower support platform body 1. When in use, after positive pressure is applied, the lower support platform body 2 floats up and can move in the Y-axis large stroke along the air-bearing guide rail surface of the lower motion platform located below the lower support platform under the drive of the Y-axis linear motor 11.

[0030] Each air bearing 14 has an adsorption area 16 in the middle. When it is necessary to fix the lower support platform, the positive pressure of the air bearing is cut off, and negative pressure is introduced into the adsorption area 16, so that the lower support platform is adsorbed onto the lower moving platform.

[0031] Two parallel linear guide rails 15 are installed on the lower surface of the lower support platform body 1. The translation and rotation component 3 is installed below the lower support platform body 1 via the two linear guide rails 15. The linear guide rails 15 provide X-direction guidance for the translation and rotation component 3.

[0032] The lower surface of the lower support platform body 1 is also equipped with an X-axis motor 12 and a reading head 13 for reading X-axis motion parameters. The X-axis motor 12 is a piezoelectric ceramic motor, which can achieve precise movement and self-lock when stationary.

[0033] like Figure 4 As shown, the translation and rotation assembly 3 includes a base plate 21. The lower suction cup 2 is mounted on the translation and rotation assembly 3 via a collar 24. The upper surface of the outer ring of the collar 24 is fixed to the lower surface of the base plate 21, and the inner ring of the collar 24 is fixedly connected to the lower part of the lower suction cup 2. The inner ring of the collar 24 is connected to the lower suction cup 2 by screws, and the outer ring of the collar 24 is connected to the translation and rotation assembly 3 by screws.

[0034] The lower suction cup 2 can rotate around the axis of the collar 24. The lower part of the lower suction cup 2 is equipped with a ceramic ring 26 and a circular grating 28 in sequence. The ceramic ring 26 and the circular grating 28 are located below the collar 24. A rotating reading head 27 for detecting the rotation angle is installed on one side of the circular grating 28.

[0035] A rotary motor 25 for driving the lower suction cup 2 to rotate is installed below the substrate 21. The rotary motor 25 is preferably a piezoelectric ceramic motor, and the contacts of the piezoelectric ceramic motor are pressed against the ceramic ring 26.

[0036] The side of the substrate 21 is equipped with an X-axis grating ruler 22 and an X-axis ceramic plate 23.

[0037] The translation and rotation assembly 3 and the lower suction cup 2 are installed on the linear guide rail 15 below the lower support platform body 1, and the contacts of the X-axis motor 12 are pressed against the X-axis ceramic plate 23.

[0038] The adjustment method of this wafer positioning mechanism is as follows:

[0039] Once the measurement system detects the deviation between the upper and lower wafers, it can determine the required rotation and movement of the lower suction cup. The lower suction cup first compensates for the angular deviation through its own rotational degree of freedom. Then, the rotary motor is de-energized, and the motor contacts press against the ceramic ring, restricting the rotational degree of freedom. Next, the X-axis deviation is compensated through the X-axis stroke of the lower suction cup. Then, the X-axis motor is de-energized, and the motor contacts press against the X-axis ceramic sheet, restricting the X-axis degree of freedom. Finally, the Y-axis deviation is compensated through the Y-axis degree of freedom of the lower support platform. Afterward, the lower support platform disconnects the air flotation and adheres to the lower motion platform, ending the compensation process.

[0040] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A wafer position adjustment mechanism for a wafer hybrid bonding apparatus, characterized in that: Includes a lower support platform body (1), the lower part of the lower suction cup (2) passes through the lower support platform body (1) and is mounted on a translational rotation assembly (3) located below the lower support platform body (1); the upper part of the lower suction cup (2) is located above the lower support platform body (1); A set of air bearings (14) is provided on both sides of the lower surface of the lower support platform body (1). A Y-axis linear motor (11) is installed in the middle of the side of the lower support platform body (1). At least one adsorption area (16) is provided in the middle of the air bearing (14). The lower support platform body (2) moves in the Y-axis large stroke along the air-bearing guide rail surface of the lower motion platform located below the lower support platform under the drive of the Y-axis linear motor (11). Two parallel linear guide rails (15) are installed on the lower surface of the lower support platform body (1). The translation and rotation assembly (3) is installed below the lower support platform body (1) through the two linear guide rails (15). The linear guide rails (15) provide X-direction guidance for the translation and rotation assembly (3). The translation and rotation assembly (3) includes a base plate (21). The lower suction cup (2) is mounted on the translation and rotation assembly (3) via a collar (24). The upper surface of the outer ring of the collar (24) is fixed to the lower surface of the base plate (21). The inner ring of the collar (24) is fixedly connected to the lower part of the lower suction cup (2). The lower suction cup (2) can rotate around the axis of the collar (24). The wafer position adjustment mechanism uses the upper support platform as a reference, and aligns the lower support platform with the upper support platform.

2. The wafer position adjustment mechanism according to claim 1, characterized in that: The lower surface of the lower support platform body (1) is equipped with an X-axis motor (12) and a reading head (13) for reading X-axis motion parameters.

3. The wafer position adjustment mechanism according to claim 2, characterized in that: The X-axis motor (12) is a piezoelectric ceramic motor or a linear motor.

4. The wafer position adjustment mechanism according to claim 3, characterized in that: The lower suction cup (2) is equipped with a ceramic ring (26) and a circular grating (28) in sequence. The ceramic ring (26) and the circular grating (28) are located below the collar (24). A rotating reading head (27) for detecting the rotation angle is installed on one side of the circular grating (28).

5. The wafer position adjustment mechanism according to claim 4, characterized in that: At least one rotary motor (25) for driving the lower suction cup (2) to rotate is installed below the substrate (21); the rotary motor is a piezoelectric ceramic motor or a torque motor.

6. The wafer position adjustment mechanism according to claim 5, characterized in that: The side of the substrate (21) is equipped with an X-axis grating ruler (22) and an X-axis ceramic plate (23).

7. The wafer position adjustment mechanism according to claim 6, characterized in that: The translation and rotation assembly (3) and the lower suction cup (2) are mounted on the linear guide rail (15) below the lower support platform body (1), and the contacts of the X-axis motor (12) are pressed against the X-axis ceramic plate (23).

8. The adjustment method of the wafer position adjustment mechanism according to any one of claims 1-7, characterized in that: Once the measurement system detects the deviation between the upper and lower wafers, it can determine the required rotation and movement of the lower suction cup. The lower suction cup first compensates for the angular deviation through its own rotational degree of freedom. Then, the rotary motor is de-energized, and the motor contacts press against the ceramic ring, restricting the rotational degree of freedom. Next, the X-axis deviation is compensated through the X-axis stroke of the lower suction cup. Then, the X-axis motor is de-energized, and the motor contacts press against the X-axis ceramic sheet, restricting the X-axis degree of freedom. Finally, the Y-axis deviation is compensated through the Y-axis degree of freedom of the lower support platform. Afterward, the lower support platform disconnects the air flotation and adheres to the lower motion platform, ending the compensation process.

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