Wafer adsorption device

Abstract

The utility model relates to wafer technology field, concretely relates to a wafer adsorption device, include: tray, tray is equipped with a plurality of independent control adsorption area to exert adsorption force to the different area of wafer bottom surface to adsorb the wafer that warps, and each adsorption area is correspondingly provided with a passageway in the tray, platform, set up below the tray, is equipped with at least one gas path, with at least one passageway intercommunication, platform is equipped with a plurality of first joint, a plurality of first joint are communicated with a plurality of passageways and gas path respectively, and a plurality of first joint all are located in the same side of platform, so as to be convenient for adjustment and maintenance, sealing assembly, set up on the wafer outer periphery of tray, when wafer and mask approach, sealing assembly and mask and tray form a closed space between, open vacuum valve, make wafer and mask be in vacuum, leveling mechanism, be located below the bearing platform and be opposite motion connection with bearing platform, be used for adjusting the parallelism of wafer and mask.

Description

Technical Field

[0001] This utility model relates to the field of wafer technology, and in particular to a wafer adsorption device. Background Technology

[0002] In the core process of semiconductor manufacturing—photolithography—the wafer serves as the fundamental carrier of the intricate patterns on integrated circuits, and the precision of its state control directly affects the quality and performance of the final chip. During the exposure process, the wafer must maintain extremely high flatness and be strictly parallel to the mask to ensure that the fine patterns etched on the mask can be completely and accurately transferred to the wafer surface.

[0003] Specifically, in the exposure process, a light source projects a pattern onto the wafer surface using a photomask. If the wafer is warped, the optical path of the projected light on the wafer surface changes. This change causes distortions in the size and shape of the projected pattern at different locations on the wafer, negatively impacting chip manufacturing quality.

[0004] However, traditional wafer adsorption devices may have certain structural design flaws, resulting in the inability to flatten warped wafers. For example, if the flatness of the adsorption surface is not ideal, the warped areas of the wafer cannot be adsorbed and flattened, thus failing to maintain the proper parallelism with the mask. Furthermore, improper layout and size design of the adsorption holes can also cause differences in adsorption force across different areas of the wafer surface, severely affecting the parallelism between the wafer and the mask.

[0005] Therefore, this application develops a wafer adsorption device to solve the problems existing in the prior art. Utility Model Content

[0006] The purpose of this invention is to provide a wafer adsorption device to solve the problems of uneven adsorption of warped wafers and poor exposure effect caused by non-parallelism with the mask in the prior art.

[0007] The technical solution of this utility model is: a wafer adsorption device, comprising: A carrier disk is used to place a wafer. The carrier disk has multiple independently controlled adsorption areas to apply adsorption force to different areas on the bottom surface of the wafer, thereby adsorbing the warped wafer. Each adsorption area is provided with a corresponding channel in the carrier disk to communicate with the outside. A platform is disposed below the carrier plate. The platform has at least one air passage connected to at least one of the channels. The platform also has multiple first connectors, which are respectively connected to multiple channels and air passages. The multiple first connectors are all located on the same side of the platform to facilitate adjustment and maintenance. A sealing assembly is disposed on the outer periphery of the wafer on the carrier disk. The sealing assembly is configured such that when the wafer approaches the mask, the sealing assembly, the mask, and the carrier disk form a sealed space, and a vacuum is drawn to form a vacuum cavity in the sealed space, so that the wafer and the mask are in a vacuum. A leveling mechanism, located below the support platform and connected to it in relative motion, is used to adjust the parallelism between the wafer and the photomask.

[0008] Preferably, the adsorption region includes a first adsorption region, a second adsorption region, and a third adsorption region arranged radially outward from the center of the carrier disk, so as to achieve independent control of different regions.

[0009] Preferably, the first adsorption area is a circular area located at the center of the carrier disk, the second adsorption area is a first sector area, a second sector area and a third sector area that surround the first adsorption area and are evenly distributed in the circumferential direction, and the third adsorption area is a concentric ring area surrounding the outer edge of the second adsorption area.

[0010] Preferably, the first sector area and the second sector area are located on the side away from the first connector, and thus the air passage is provided in two parts, which are respectively connected to the channels of the first connectors corresponding to the first sector area and the second sector area, so that the first connector connecting the first sector area and the second sector area is located on the same side as the other first connectors.

[0011] Preferably, the sealing assembly is disposed on the carrier disk and has a first state and a second state; when the wafer reaches a preset distance, the sealing assembly is vented through the second connector and converted to the first state, with its top protruding from the upper surface of the carrier disk and sealingly abutting against the bottom surface of the mask, thereby forming a sealed space, and the sealed space is connected to a third connector for keeping the sealed space in a vacuum state. After exposure is complete, the sealing assembly is evacuated through the second connector to switch to the second state, and its top retracts to the surface of the carrier disk.

[0012] Preferably, the adjustment mechanism includes three adjustment sections evenly distributed circumferentially below the stage; each adjustment section contacts the lower surface of the stage through a ball bearing, thereby achieving wafer parallelism calibration through the ball bearing.

[0013] Preferably, each of the adjustment sections is provided with a locking cylinder below it. After the parallelism calibration is completed, the locking cylinder locks the adjustment section to maintain the parallelism between the wafer and the mask.

[0014] Compared with the prior art, the advantages of this utility model are: (1) The bearing platform has multiple independent vacuum channels extending to each adsorption area, which can independently adjust the adsorption force of each adsorption area according to actual needs. Furthermore, the 12-inch wafer is uniformly adsorbed at the edge by the third adsorption area, and the warped wafer is adsorbed flat. (2) The sealing component has an inflated state and a non-inflated state. During photolithography exposure, the sealing component is inflated to form a closed vacuum cavity between the mask, the sealing component and the carrier platform, so that the projection light is more stable in incident and propagation on the wafer surface. At the same time, the vacuum environment is more conducive to the propagation of light, ensuring that the projection pattern is accurately transferred to the wafer surface and improving the pattern transfer accuracy. (3) Each adjustment section is equipped with a locking cylinder. When the wafer is parallel to the mask, the locking cylinder locks the adjustment section to ensure that the wafer remains parallel to the mask during the exposure process. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the structure of the wafer adsorption device described in this utility model; Figure 2 This is a distribution diagram of the adsorption regions described in this utility model; Figure 3 This is a cross-sectional view of the platform described in this utility model; Figure 4 This is a partial sectional view of the leveling mechanism described in this utility model; Figure 5 This is a side sectional view of the leveling mechanism described in this utility model.

[0016] Wherein: 1. Carrier disk; 11. Adsorption area; 111. First adsorption area; 112. Second adsorption area; 1121. First sector area; 1122. Second sector area; 1123. Third sector area; 113. Third adsorption area; 12. Channel; 2. Sealing assembly; 3. Leveling mechanism; 31. Adjustment part; 32. Ball bearing; 33. Locking cylinder; 4. Vacuum chamber; 5. Stage; 51. Air passage; 52. First connector; 53. Second connector; 54. Third connector; 55. Fourth connector. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to specific embodiments: like Figures 1-3As shown, a wafer adsorption device includes a carrier disk 1, a sealing assembly 2, a leveling mechanism 3, and a stage 5. The carrier disk 1 is used to support the wafer and has multiple independently controlled adsorption areas 11 to flatten the warped edges of the 12-inch wafer. Each adsorption area 11 has a corresponding passage 12 on the carrier disk to connect to the outside, facilitating ventilation for wafer adsorption. The stage 5 is located below the carrier disk 1 and uses a fourth connector 55 for vacuum adsorption to adsorb the carrier disk 1 onto the stage 5. The stage 5 has two air passages connected to one adsorption area 11 and multiple first connectors 52. The first connectors 52 are directly connected to the channel 12 and then vacuumed to adsorb the wafer, or connected to the channel 12 through the air passage 51 to adsorb the wafer in other areas. The sealing component 2 is located on the outer periphery of the wafer on the carrier disk 1. During the photolithography process, when the wafer and the mask gradually approach each other, the sealing component 2 can closely cooperate with the mask and the carrier platform 1 to form a sealed space. Vacuuming is performed on the sealed space, which is more conducive to the propagation of light and improves the exposure effect.

[0018] In practical applications, the wafer adsorption device is set in a confined space and is surrounded by other structures. Only one side is detachable. Therefore, multiple first connectors 52 are located on this side of the stage 5. When adjustment or maintenance is required, the adsorption state on the entire tray 1 can be adjusted from only one side.

[0019] In addition, during wafer exposure, it is necessary to ensure the levelness of the wafer and the photomask. Therefore, a leveling mechanism 3 is provided below the stage 5, and the leveling mechanism 3 is connected to the stage 5 for relative movement. In practical applications, when the wafer is placed on the carrier tray 1, due to the change in load, the carrier tray 1 cannot guarantee that the wafer on it remains parallel to the photomask. The leveling mechanism 3 includes three adjustment parts 31, all distributed below the carrier platform 1. The adjustment parts 31 contact the lower surface of the stage 5 through ball bearings 32. The three ball bearings 32 form a plane, thereby adjusting the wafer to maintain its parallelism with the photomask.

[0020] Furthermore, such as Figures 4-5 As shown, each adjustment section 31 is equipped with a locking cylinder 33 below it. When the wafer is parallel to the mask, the locking cylinder 33 locks the adjustment section 31 to maintain the parallelism between the wafer and the mask. This prevents the position of the adjustment section 31 from changing due to equipment vibration or other factors when the carrier platform 1 carries the wafer close to the mask. This ensures that the wafer remains parallel to the mask throughout the entire process.

[0021] In this embodiment, as Figure 1 and Figure 5As shown, the sealing component 2 is disposed within the carrier disk 1. The sealing component 2 is an inflatable sealing ring, which has a first state and a second state, namely an inflated state and a non-inflated state. During the photolithography exposure process, when the mask and the wafer reach a preset distance, air is injected into the sealing component 2 through the second connector 53, causing the sealing component 2 to switch to the first state. At this time, the top of the sealing component 2 protrudes from the upper surface of the carrier disk 1 and achieves a sealed contact with the bottom surface of the mask, thereby forming a sealed space between the mask, the sealing component 2, and the carrier disk 1. The sealed space is connected to the third connector 54. Air is extracted through the third connector 54 to form a vacuum chamber 4 in the sealed space, so that the pressure between the wafer and the mask reaches a balanced state, thereby ensuring that the projected pattern can be accurately transferred to the wafer surface and improving the accuracy of pattern transfer. After exposure is completed, the sealing component 2 is deflated through the second connector, switching to the second state, and the top of the sealing component 2 retracts back to the surface of the carrier disk 1.

[0022] like Figure 2 As shown, in this embodiment, the adsorption region 11 includes a first adsorption region 111, a second adsorption region 112, and a third adsorption region 113 arranged radially outward from the center of the carrier disk 1. Specifically, the first adsorption region 111 is a circular region located at the center of the carrier platform 1. The second adsorption region 112 consists of a plurality of first sector regions, second sector regions, and third sector regions that surround the first adsorption region 111 and are evenly distributed circumferentially. Each sector region can independently control the adsorption force. The third adsorption region 113 is a concentric ring region surrounding the outer edge of the second adsorption region 112, which is responsible for adsorbing the wafer edge portion. The concentric ring design allows the adsorption force to be evenly distributed on the wafer edge, effectively preventing the wafer edge from warping or deforming.

[0023] Furthermore, the first sector 1121 and the second sector 1122 are located on the side away from the first connector 52. In order to make the first connector 52 connecting the first sector 1121 and the second sector 1122 on the same side as other first connectors 52, two air passages 51 are provided in the platform 5 to connect the corresponding air passages 51 and the first connectors 52, so that all the first connectors 52 are on the same side, which is convenient for the construction personnel to adjust.

[0024] In practical applications, the first adsorption region 111 and the second adsorption region 112 adsorb the middle part of the 12-inch wafer. Since the 12-inch wafer is thinner, it is prone to warping at the edge. Warping will affect the exposure of the wafer. Therefore, the third adsorption region 113 is set at the edge of the wafer of this size, which can generate a uniform adsorption force on the edge, thereby avoiding the warping of the wafer.

[0025] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. It is obvious to those skilled in the art that this utility model is not limited to the details of the above exemplary embodiments, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and therefore, all changes falling within the meaning and scope of the equivalents of the claims are intended to be included within this utility model.

Claims

1. A wafer adsorption device, characterized in that, include: The carrier disk (1) is used to place the wafer. The carrier disk (1) is provided with multiple independently controlled adsorption areas (11) to apply adsorption force to different areas of the bottom surface of the wafer, thereby adsorbing the warped wafer. Each adsorption area (11) is provided with a channel (12) in the carrier disk (1) to communicate with the outside. A platform (5) is provided below the tray (1). The platform (5) has at least one air passage (51) connected to at least one of the channels (12). The platform (5) is also provided with multiple first connectors (52). The multiple first connectors (52) are respectively connected to the multiple channels (12) and the air passage (51). The multiple first connectors (52) are all located on the same side of the platform (5) for easy adjustment and maintenance. A sealing component (2) is disposed on the outer periphery of the wafer on the carrier disk (1). The sealing component (2) is configured such that when the wafer approaches the mask, the sealing component (2) forms a sealed space between the mask and the carrier disk (1), and a vacuum is drawn to form a vacuum cavity (4) in the sealed space, so that the wafer and the mask are in a vacuum. The leveling mechanism (3) is located below the carrier platform (1) and is connected to the carrier platform (1) in relative motion. It is used to adjust the parallelism between the wafer and the mask.

2. The wafer adsorption device according to claim 1, characterized in that: The adsorption region (11) includes a first adsorption region (111), a second adsorption region (112) and a third adsorption region (113) arranged radially outward from the center of the carrier disk (1) to achieve independent control of different regions.

3. The wafer adsorption device according to claim 2, characterized in that: The first adsorption area (111) is a circular area located at the center of the carrier disk (1), the second adsorption area (112) is a first sector area (1121), a second sector area (1122) and a third sector area (1123) that surround the first adsorption area (111) and are evenly distributed in the circumferential direction, and the third adsorption area (113) is a concentric ring area surrounding the outer edge of the second adsorption area (112).

4. The wafer adsorption device according to claim 3, characterized in that: The first sector (1121) and the second sector (1122) are located on the side away from the first connector (52). Therefore, the air passage (51) is provided in two, which are respectively connected to the channels (12) of the first connector (52) corresponding to the first sector (1121) and the second sector (1122), so that the first connector (52) connecting the first sector (1121) and the second sector (1122) is located on the same side as the other first connectors (52).

5. The wafer adsorption device according to claim 1, characterized in that: The sealing component (2) is disposed on the carrier disk (1) and has a first state and a second state. When the wafer reaches a preset distance, the sealing component (2) is vented through the second connector (53) and converted to the first state. Its top protrudes from the upper surface of the carrier disk (1) and seals against the bottom surface of the mask, thereby forming a sealed space. The sealed space is connected to a third connector (54) for making the sealed space a vacuum state. After exposure is complete, the sealing assembly (2) is evacuated through the second connector (53) to switch to the second state, and its top retracts to the surface of the carrier disk (1).

6. The wafer adsorption device according to claim 3, characterized in that: The leveling mechanism (3) includes three adjustment parts (31) evenly distributed circumferentially below the stage; each adjustment part (31) contacts the lower surface of the stage through a ball (32) to achieve wafer parallelism calibration.

7. A wafer adsorption device according to claim 6, characterized in that: Each of the adjustment sections (31) is provided with a locking cylinder (33) below it. After the parallelism calibration is completed, the locking cylinder (33) locks the adjustment section (31) to maintain the parallelism between the wafer and the mask.

Images