Wafer center pre-alignment device and wafer transfer system

Abstract

The application provides a wafer center pre-alignment device and a wafer transmission system, and relates to the technical field of semiconductors.The wafer center pre-alignment device comprises a first chuck and a second chuck sleeved in the first chuck, and the first chuck and the second chuck are used for carrying a wafer.The second chuck is respectively connected with a first driving part and a second driving part.The first driving part is used for driving the second chuck to move up and down along a first direction, and the second driving part is used for driving the second chuck to move along a second direction.The movement of the second chuck along the first direction and the second direction is used for making the geometric center of the wafer coincide with the rotation center of the first chuck, and the first direction is perpendicular to the second direction.In the process of aligning the geometric center of the wafer with the rotation center of the first chuck, the movement of the wafer along the second direction can be controlled through the second driving part, so that the wafer scratch problem caused by gravity deformation in the movement process of the wafer can be reduced, and the quality of the wafer can be effectively ensured.

Description

Technical Field

[0001] This application relates to the field of semiconductor technology, specifically to a wafer center pre-alignment device and a wafer transport system. Background Technology

[0002] Before being exposed in the stage module of a lithography machine, the wafer needs to undergo pre-alignment and temperature control in the machine's wafer transport system. For example... Figure 1 As shown, when the wafer is pre-aligned in the wafer transport system, the chuck 1 holds the center of the wafer and drives the wafer to rotate. The wafer pre-alignment sensor calculates the geometric center of the wafer, and then the chuck 2 moves the wafer so that the center of the wafer coincides with the center of the chuck 1.

[0003] During the wafer movement process, chuck 2 first lifts the wafer to a certain height before moving it. During this movement, the wafer can be considered a long cantilever structure, deforming and drooping under gravity. The deformed portion of the wafer may come into contact with chuck 1 or other components, causing scratches. Furthermore, if the wafer's center position is adjusted, the airflow disturbances within the system during movement increase the risk of scratches from the method of pulling the wafer from one side by chuck 2, thus impacting wafer quality. Utility Model Content

[0004] The purpose of this application is to provide a wafer center pre-alignment device and a wafer transfer system, which can reduce scratches caused during wafer movement and ensure wafer quality.

[0005] In one aspect of this application, a wafer center pre-alignment device is provided, including a first chuck and a second chuck sleeved within the first chuck. The first chuck and the second chuck are used to carry a wafer. The second chuck is respectively connected to a first driving component and a second driving component. The first driving component is used to drive the second chuck to move up and down along a first direction, and the second driving component is used to drive the second chuck to move along a second direction. Through the movement of the second chuck along the first direction and the second direction, the geometric center of the wafer coincides with the rotation center of the first chuck, and the first direction and the second direction are perpendicular.

[0006] Optionally, the first driving component includes a lifting motor to drive the second chuck to move up and down along the first direction; the second driving component includes a horizontal motor to drive the second chuck to move along the second direction.

[0007] Optionally, the first chuck has a cavity, the second chuck is disposed within the cavity of the first chuck, and the first driving component and the second driving component pass through the cavity to connect with the second chuck.

[0008] Optionally, it further includes a first sensing component for detecting the height of the second chuck relative to the first chuck, the height being between 0.1 mm and 2 mm.

[0009] Optionally, a second sensing component disposed on one side of the first chuck is further included. The second sensing component detects the edge of the wafer to determine the distance between the geometric center of the wafer and the rotation center of the first chuck.

[0010] Optionally, the second driving component drives the second chuck to move along the second direction toward the rotation center of the first chuck, and the distance of a single movement is 1 / 2 of the distance between the rotation center of the first chuck and the geometric center of the wafer.

[0011] Optionally, the first chuck is connected to a third driving component, the third driving component including a rotary motor, the third driving component being used to drive the first chuck to rotate, so that the first chuck drives the wafer to rotate.

[0012] Optionally, it also includes a temperature control component, which is sleeved outside the first chuck, and along the first direction, the top surface of the temperature control component is lower than the top surface of the first chuck. The temperature control component is used to control the temperature of the wafer so that the temperature of the wafer meets a preset temperature.

[0013] Optionally, both the first chuck and the second chuck are vacuum suction cups.

[0014] In another aspect of this application, a wafer transfer system is provided, including the wafer center pre-alignment device described above.

[0015] The wafer center pre-alignment device and wafer transfer system provided in this application embodiment can control the movement of the wafer along a second direction by means of a second driving component during the alignment of the geometric center of the wafer with the rotation center of the first chuck. This can reduce wafer scratches caused by gravitational deformation during wafer movement and effectively ensure wafer quality. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a wafer center pre-alignment device in the prior art; Figure 2 This is one of the schematic diagrams of the wafer center pre-alignment device provided in this embodiment; Figure 3 This is the second schematic diagram of the wafer center pre-alignment device provided in this embodiment; Figure 4 This is a diagram illustrating the wafer alignment confirmation process of the wafer center pre-alignment device provided in this embodiment; Figure 5 This is a diagram illustrating the adjustment process of the wafer center pre-alignment device provided in this embodiment.

[0018] Icons: 1, 2 - Chucks; 11 - First Chuck; 12 - Second Chuck; 13 - Third Drive Component; 14 - Second Drive Component; 16 - First Drive Component; 17 - Second Sensing Component; 18 - First Sensing Component; S1 - Rotation Center; S2 - Geometric Center; F1 - First Direction; F2 - Second Direction. Detailed Implementation

[0019] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0020] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0021] It should also be noted that, unless otherwise explicitly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0022] Please refer to Figure 2 , Figure 3 As shown, this application embodiment provides a wafer center pre-alignment device, including: a first chuck 11 and a second chuck 12 sleeved inside the first chuck 11. The first chuck 11 and the second chuck 12 are used to carry the wafer. The second chuck 12 is respectively connected to a first driving component 16 and a second driving component 14. The first driving component 16 is used to drive the second chuck 12 to move up and down along a first direction F1, and the second driving component 14 is used to drive the second chuck 12 to move along a second direction F2. Through the movement of the second chuck 12 along the first direction F1 and the second direction F2, the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11, and the first direction F1 and the second direction F2 are perpendicular.

[0023] The second chuck 12 is fitted inside the first chuck 11, and the second chuck 12 can be raised and lowered along the first direction F1; when the second chuck 12 returns to the initial state, the second chuck 12 and the first chuck 11 have flush bearing surfaces, and the wafer is carried on the bearing surface, and the wafer is set horizontally along the second direction F2.

[0024] For example, both the first chuck 11 and the second chuck 12 are vacuum chucks, which use vacuum adsorption to adsorb wafers.

[0025] The first chuck 11 is used to drive the wafer to rotate, and the second chuck 12 is used to move the wafer so that the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11.

[0026] Specifically, the first chuck 11 is connected to a third driving component 13, which includes a rotary motor. The third driving component 13 is used to drive the first chuck 11 to rotate, so that the first chuck 11 drives the wafer to rotate.

[0027] When the second chuck 12 moves the wafer, it first lifts the wafer with the first driving component 16, and then moves the wafer along the second direction F2 with the second driving component 14 to a position where the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11, thereby completing the pre-alignment of the wafer with the first chuck 11.

[0028] Furthermore, it also includes a first sensing component 18, which is used to detect the height of the second chuck 12 relative to the first chuck 11, the height being between 0.1 mm and 2 mm.

[0029] After the first driving component 16 lifts the wafer, it facilitates the movement of the wafer by the second driving component 14. The lifting height should not be too high to avoid the wafer slipping or shifting from the second chuck 12, nor should it be too low, otherwise it will be inconvenient for the second driving component 14 to move the wafer. This application limits the lifting height to between 0.1 mm and 2 mm, which meets the above requirements.

[0030] When the wafer moves along the second direction F2, the edge of the wafer can be detected by the second sensing component 17 to determine the distance between the geometric center S2 of the wafer and the rotation center S1 of the first chuck 11. The second sensing component 17 is disposed on one side of the first chuck 11.

[0031] Furthermore, in order to ensure the accuracy of wafer movement, when the second drive component 14 drives the second chuck 12 to move along the second direction F2 toward the rotation center S1 of the first chuck 11, the distance of a single movement is 1 / 2 of the distance between the rotation center S1 of the first chuck 11 and the geometric center S2 of the wafer, until the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11.

[0032] For example, if the second drive component 14 drives the second chuck 12 to the left along the second direction F2, and the single drive distance of the second drive component 14 is too large, it may move the wafer to the left beyond the position where the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11. In this case, the wafer needs to be moved to the right, and so on, which is not conducive to the efficiency of wafer alignment. On the other hand, if the single drive distance of the second drive component 14 is too small, it will take multiple drives to move the wafer into place, which will also reduce the efficiency of wafer alignment. Therefore, the wafer movement distance needs to be set within a reasonable range.

[0033] The wafer center pre-alignment device provided in this application embodiment can control the movement of the wafer along the second direction F2 by the second driving component 14 during the alignment process between the geometric center S2 of the wafer and the rotation center S1 of the first chuck 11. This can reduce wafer scratches caused by gravity deformation during wafer movement and effectively ensure wafer quality.

[0034] In some embodiments, the first driving component 16 includes a lifting motor to drive the second chuck 12 to move up and down along the first direction F1; the second driving component 14 includes a horizontal motor to drive the second chuck 12 to move along the second direction F2, so that the geometric center S2 of the wafer coincides with the rotation center S1 of the first chuck 11.

[0035] The first chuck 11 has a cavity, and the second chuck 12 is disposed within the cavity of the first chuck 11. The first drive component 16 and the second drive component 14 pass through the cavity to connect with the second chuck 12.

[0036] The first chuck 11 is provided with a cavity to accommodate the second chuck 12. In addition, since the second chuck 12 needs to move horizontally along the second direction F2, the size of the cavity of the first chuck 11 along the second direction F2 needs to meet the movement range of the second chuck 12 in the second direction F2 so that the second chuck 12 can move within the cavity, ultimately causing the geometric center S2 of the wafer to coincide with the rotation center S1 of the first chuck 11.

[0037] The first driving component 16 and the second driving component 14 need to be inserted into the cavity so that they can act on the second chuck 12 and drive the second chuck 12 to move in the first direction F1 and the second direction F2.

[0038] On the other hand, it also includes a temperature control component, which is sleeved outside the first chuck 11 and along the first direction F1. The top surface of the temperature control component is lower than the top surface of the first chuck 11. The temperature control component is used to control the temperature of the wafer so that the temperature of the wafer meets the preset temperature.

[0039] Each of the above components can also be connected to a control unit, which can acquire data from each component and drive the components to operate based on this data.

[0040] For example, the control unit is connected to the first sensing unit 18 to obtain the lifting height of the second chuck 12 detected by the first sensing unit 18, and controls the first driving unit 16 according to the lifting height to control the lifting height of the second chuck 12 within a preset range.

[0041] When the wafer center pre-alignment device of this application is working, the wafer is transferred from the coating and developing machine to the wafer transport system and placed on the first chuck 11 of the wafer center pre-alignment device. The first chuck 11 holds the wafer by vacuum suction. Then, the rotary motor of the first chuck 11 operates, driving the first chuck 11 and the wafer to rotate. The second wafer sensing component 17 scans the edge of the rotating wafer to calculate the rotation center S1 and the geometric center S2 of the wafer. After confirming the geometric center S2 of the wafer and the rotation center S1 of the first chuck 11, the rotary motor of the first chuck 11 is controlled to rotate the wafer so that the geometric center S2 of the wafer is located at the rightmost side of the rotation center S1 of the first chuck 11. Figure 4 As shown.

[0042] Then, the second chuck 12 is vacuumed, and the vacuum of the first chuck 11 is deactivated. The second chuck 12 then takes over from the first chuck 11 to pick up the wafer. Afterwards, the lifting motor of the second chuck 12 raises it by 0.1mm to 2mm. The lifting height of the second chuck 12 is monitored by the first sensor 18. The horizontal motor of the second chuck 12 pushes it to the left, moving a distance equal to half the distance between the rotation center S1 of the first chuck 11 and the geometric center S2 of the wafer. Figure 5 As shown. Repeat the previous steps, recalculate the position of the rotation center S1 of the first chuck 11 and the geometric center S2 of the wafer, and adjust the position of the geometric center S2 of the wafer until the rotation center S1 of the first chuck 11 and the geometric center S2 of the wafer coincide, thus completing the pre-alignment of the wafer.

[0043] Based on this, embodiments of this application also disclose a wafer transfer system, including a wafer center pre-alignment device as described above.

[0044] This wafer transfer system includes the same structure and beneficial effects as the wafer center pre-alignment device in the foregoing embodiments. The structure and beneficial effects of the wafer center pre-alignment device have been described in detail in the foregoing embodiments and will not be repeated here.

[0045] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A wafer center pre-alignment device, characterized in that, include: A first chuck and a second chuck fitted inside the first chuck, the first chuck and the second chuck are used to carry the wafer, the second chuck is respectively connected to a first driving component and a second driving component, the first driving component is used to drive the second chuck to move up and down in a first direction, the second driving component is used to drive the second chuck to move in a second direction, through the movement of the second chuck in the first direction and the second direction, so that the geometric center of the wafer coincides with the rotation center of the first chuck, the first direction and the second direction are perpendicular.

2. The wafer center pre-alignment device according to claim 1, characterized in that, The first driving component includes a lifting motor to drive the second chuck to move up and down along the first direction; the second driving component includes a horizontal motor to drive the second chuck to move along the second direction.

3. The wafer center pre-alignment device according to claim 2, characterized in that, The first chuck has a cavity, and the second chuck is disposed within the cavity of the first chuck. The first driving component and the second driving component pass through the cavity to connect with the second chuck.

4. The wafer center pre-alignment device according to claim 1, characterized in that, It also includes a first sensing component, which is used to detect the height of the second chuck relative to the first chuck, the height being between 0.1 mm and 2 mm.

5. The wafer center pre-alignment apparatus according to any one of claims 1 to 4, characterized in that, It also includes a second sensing component disposed on one side of the first chuck, the second sensing component detecting the edge of the wafer to determine the distance between the geometric center of the wafer and the rotation center of the first chuck.

6. The wafer center pre-alignment apparatus according to claim 5, characterized in that, The second driving component drives the second chuck to move along the second direction toward the rotation center of the first chuck, and the distance of a single movement is 1 / 2 of the distance between the rotation center of the first chuck and the geometric center of the wafer.

7. The wafer center pre-alignment apparatus according to any one of claims 1 to 4, characterized in that, The first chuck is connected to a third driving component, which includes a rotary motor. The third driving component is used to drive the first chuck to rotate, so that the first chuck drives the wafer to rotate.

8. The wafer center pre-alignment apparatus according to any one of claims 1 to 4, characterized in that, It also includes a temperature control component, which is sleeved outside the first chuck, and along the first direction, the top surface of the temperature control component is lower than the top surface of the first chuck. The temperature control component is used to control the temperature of the wafer so that the temperature of the wafer meets the preset temperature.

9. The wafer center pre-alignment apparatus according to any one of claims 1 to 4, characterized in that, Both the first chuck and the second chuck are vacuum suction cups.

10. A wafer transmission system, characterized in that, Includes the wafer center pre-alignment apparatus as described in any one of claims 1 to 9.

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