Wafer warpage correction device

Abstract

This application relates to a wafer warpage correction device, comprising: a housing; a correction assembly for correcting a warped wafer, including a lower plate assembly, an upper plate assembly, and a driving component. The warped wafer can be placed on the lower plate assembly, and the driving component can drive the upper plate assembly to move toward the lower plate assembly to correct the warped wafer. The lower plate assembly includes a suction cup, a first heating plate located below the suction cup, and a first water-cooling plate. The first heating plate includes a first heating area and a second heating area surrounding the first heating area. The temperature of the first heating area is lower than the temperature of the second heating area, so that when the wafer is adsorbed by the suction cup, the wafer can be heated on demand. Higher temperatures are applied to the severely warped surrounding areas to efficiently release stress and promote morphological recovery, while lower temperatures are used for the naturally flat middle area to avoid generating new thermal stress. This significantly improves the efficiency and accuracy of warpage repair and reduces the risk of secondary deformation after correction.

Description

Technical Field

[0001] This application relates to the field of wafer processing technology, and specifically to a wafer warpage correction device. Background Technology

[0002] In semiconductor manufacturing, wafers undergo multiple processes including deposition, etching, ion implantation, and thermal bonding. Due to temperature cycling and stress accumulation during these processes, wafers are highly susceptible to warping, with most warping patterns characterized by a relatively flat central area and upward-curving edges. This warping significantly impacts the processing accuracy of subsequent steps such as photolithography, bonding, dicing, and packaging, leading to issues like pattern transfer deviations, reduced bonding yield, and dicing damage. Ultimately, this reduces the overall yield of semiconductor products and increases production costs.

[0003] To address wafer warpage, various wafer warpage correction devices have emerged in the prior art. However, these devices typically apply pressure to the wafer using upper and lower pressure plates and heat the entire wafer to release internal stress, thereby achieving warpage correction. However, the heating structures of these correction devices are mostly monolithic heating designs, meaning they uniformly heat the entire wafer surface through a single heating zone. But as mentioned earlier, wafer warpage is mainly concentrated in the periphery, while the central area is relatively flat and does not require excessively high temperatures to maintain its flatness. Monolithic heating cannot provide targeted temperature control based on the wafer's warpage characteristics. The warped periphery struggles to obtain sufficient temperature to effectively release stress, while the flat central area may experience overheating, generating new thermal stress. This results in low correction efficiency, poor correction effects, and may even exacerbate secondary wafer deformation.

[0004] Therefore, it is necessary to improve the existing technology to overcome the aforementioned defects. Summary of the Invention

[0005] In view of this, embodiments of this application provide a wafer warpage correction device to solve at least one problem existing in the prior art, comprising:

[0006] The shell has a cavity;

[0007] A correction assembly, located within the cavity, is used to correct a warped wafer. It includes a lower plate assembly, an upper plate assembly, and a drive unit connected to the upper plate assembly. The warped wafer can be placed on the lower plate assembly, and the drive unit can drive the upper plate assembly to move toward the lower plate assembly to correct the warped wafer.

[0008] The lower plate assembly includes a suction cup, a first heating plate located below the suction cup, and a first water-cooling plate. The first heating plate includes a first heating area and a second heating area surrounding the first heating area. The temperature of the first heating area is lower than the temperature of the second heating area. The upper plate assembly includes a second heating plate. The calibration component is configured such that when the wafer is placed on the lower plate assembly, the first heating area heats the central region of the wafer, and the second heating area heats the edge region of the wafer. At the same time, the second heating plate presses against the wafer to maintain pressure on the wafer.

[0009] Optionally, in the above-mentioned wafer warpage correction device, the suction cup includes a first adsorption area and a second adsorption area surrounding the outside of the first adsorption area. The first adsorption area is provided with a plurality of first adsorption ports, and the second adsorption area is provided with a plurality of second adsorption ports.

[0010] Optionally, in the above-described wafer warpage correction device, the distance from the first adsorption port to the center point is less than 2 / 3 of the radius of the first adsorption region, and the distance from the second adsorption port to the center point is less than 2 / 3 of the radius of the second adsorption region.

[0011] Optionally, in the above-mentioned wafer warpage correction device, the lower plate assembly further includes a first heat insulation plate, a support plate, and a second heat insulation plate disposed below the first water-cooling plate. The support plate is a steel plate, and the first and second heat insulation plates are both mica plates.

[0012] Optionally, in the above-described wafer warpage correction device, the lower plate assembly further includes a second water-cooling plate disposed below the second heat insulation plate.

[0013] Optionally, in the above-mentioned wafer warpage correction device, the upper plate assembly includes a third water-cooling plate, a third heat insulation plate, and a pressure plate arranged sequentially from bottom to top.

[0014] Optionally, in the above-described wafer warpage correction device, the temperature of the second heating plate tends to be the same as the temperature of the first heating zone.

[0015] Optionally, the wafer warpage correction device described above further includes a connector connected to the upper plate assembly and a leveling component cooperating with the connector. The driving component can drive the leveling component to move the upper plate assembly so that the upper plate assembly is parallel to the lower plate assembly.

[0016] Optionally, in the above-mentioned wafer warpage correction device, the leveling component includes an adjustment plate connected to the driving component and a universal adjustment ball mounted on the adjustment plate. The edge of the adjustment plate is connected to the housing via a linear guide rod, and the edge of the adjustment plate is movably connected to the connecting seat. The connecting seat is provided with an adjustment groove adapted to the universal adjustment ball.

[0017] Optionally, the wafer warpage correction device described above further includes a nitrogen gas assembly connected to the cavity.

[0018] Compared with the prior art, this application has the following beneficial effects: by providing a suction cup, a first heating plate, and a first water-cooling plate in the lower plate assembly, and a second heating plate in the upper plate assembly, the first heating plate is divided into a first heating area and a second heating area surrounding the first heating area, and the temperature of the first heating area is lower than that of the second heating area. When the wafer is attracted by the suction cup, the first heating area heats the central area of ​​the wafer at a lower temperature, and the second heating area heats the edge area of ​​the wafer at a higher temperature than that of the first heating area. At the same time, the second heating plate presses firmly on the wafer to maintain pressure, thereby achieving on-demand heating of the wafer. This allows the first heating plate to provide a mild and stable correction environment for the wafer during the wafer correction process, preventing deformation of the upper plate assembly. In addition, the partitioned heating of the first heating plate, combined with the second heating plate, creates a temperature difference on both the horizontal and vertical surfaces of the wafer edge, thereby applying stronger thermal excitation to the warped wafer edge, enhancing its plastic deformation ability and promoting shape recovery. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the wafer warpage correction module shown in this embodiment;

[0020] Figure 2 for Figure 1 A cross-sectional schematic diagram of the wafer warp correction module shown;

[0021] Figure 3 for Figure 1 A cross-sectional view of the wafer warp correction module from another direction is shown.

[0022] Figure 4 for Figure 1 The diagram shows the structure of the lower plate assembly of the wafer warp correction module.

[0023] Reference numerals: Housing-1, Cavity-11, Correction assembly-2, Lower plate assembly-21, Suction cup-211, First suction port-2113, Second suction port-2114, First heating plate-212, First heating zone-2121, Second heating zone-2122, First water cooling plate-213, First heat insulation plate-214, Support plate-215, Second heat insulation plate-216, Second water cooling plate-217, Upper plate assembly-22, Third water cooling plate-221, Second heating plate-222, Third heat insulation plate-223, Pressure plate-224, Driving component-23, Connecting seat-4, Adjustment groove-41, Leveling assembly-5, Adjustment plate-51, Universal adjusting ball-52, Linear guide rod-53. Detailed Implementation

[0024] The exemplary embodiments disclosed in this application will now be described in more detail. Numerous specific details are set forth in the following description to provide a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be implemented without one or more of these details. In other instances, to avoid confusion with this application, some technical features well-known in the art have not been described; that is, not all features of actual embodiments are described herein, nor are well-known functions and structures described in detail.

[0025] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion. And the discussion of a second element, component, area, layer, or portion does not imply that the first element, component, area, layer, or portion necessarily exists in this application.

[0026] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used here for convenience to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of devices in use and operation.

[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “ / the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “compose” and / or “comprising,” when used in this specification, identify the presence of features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0028] To fully understand this application, detailed steps and structures will be presented in the following description to illustrate the technical solution of this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0029] Please refer to Figures 1-4. A preferred embodiment of this application shows a wafer warpage correction device for correcting warped wafers. The wafer warpage correction device includes a housing 1 with a cavity 11, a correction component 2, and a nitrogen component (not shown). It should be noted that in this embodiment, the nitrogen component is connected to the cavity 11 and is used to fill the cavity 11 with nitrogen gas, so that the warped wafer processing is conducted in a nitrogen environment. On the one hand, this isolates the wafer from air, preventing oxidation during the heating correction process and ensuring the material properties and surface quality of the wafer. On the other hand, the stability of nitrogen gas maintains the consistency of the environment inside the cavity 11, reducing interference from external factors on temperature control and the correction process. Simultaneously, the heat dissipation characteristics of nitrogen gas help regulate the temperature inside the cavity 11, improving the stability of the device operation.

[0030] Specifically, the correction component 2 is located inside the cavity 11 and is used to correct the warped wafer. It includes a lower plate assembly 21, an upper plate assembly 22, and a drive unit 23 connected to the upper plate assembly 22. The warped wafer can be placed on the lower plate assembly 21, and the drive unit 23 can drive the upper plate assembly 22 to move toward the lower plate assembly 21 to correct the warped wafer.

[0031] More specifically, the lower plate assembly 21 includes a suction cup 211, a first heating plate 212 located below the suction cup 211, and a first water-cooling plate 213. The upper plate assembly 22 includes a second heating plate 222. The first heating plate 212 includes a first heating area 2121 and a second heating area 2122 surrounding the outside of the first heating area 2121. The temperature of the first heating area 2121 is lower than the temperature of the second heating area 2122. The upper plate assembly 22 includes the second heating plate 222. When the wafer is placed on the lower plate assembly 21, the first heating area 2121 heats the central region of the wafer, and the second heating area 2122 heats the edge region of the wafer. At the same time, the second heating plate 222 presses against the wafer to maintain pressure.

[0032] Understandably, since wafer warping is mostly characterized by a flat center and warped edges, by dividing the first heating plate 212 into an inner first heating zone 2121 and an outer second heating zone 2122, and setting the temperature of the first heating zone 2121 to be lower than that of the second heating zone 2122, when the wafer is adsorbed by the chuck, the first heating zone 2121 heats the central region of the wafer at a lower temperature, while the second heating zone 2122 heats the edge region of the wafer at a higher temperature than that of the first heating zone 2121. At the same time, the second heating plate 222 is pressed firmly on top of the wafer to maintain pressure, thereby achieving on-demand heating of the wafer. This allows the first heating plate 212 to provide a gentle and stable correction environment for the wafer during the wafer correction process, preventing deformation of the upper board assembly 22. Furthermore, the partitioned heating of the first heating plate 212, combined with the second heating plate 222, creates a temperature difference on both the horizontal and vertical surfaces of the wafer edge, thereby applying stronger thermal excitation to the warped wafer edge, enhancing its plastic deformation ability and promoting shape recovery. Meanwhile, a first water-cooling plate 213 is provided below the first heating plate 212, so that the first water-cooling plate 213 can cool down the heating temperature of the first heating plate 212, achieve precise temperature control, and avoid high temperature damage to the performance of wafer materials.

[0033] It should be noted that the temperature of the second heating plate 222 is close to the temperature of the first heating zone 2121. In this embodiment, the temperature range of the first heating zone and the second heating plate is 120℃-180℃, and the temperature range of the second heating zone is 200℃-280℃.

[0034] Furthermore, the suction cup 211 includes a first adsorption area and a second adsorption area surrounding the outside of the first adsorption area. The first adsorption area is provided with a plurality of first adsorption ports 2113, and the second adsorption area is provided with a plurality of second adsorption ports 2114.

[0035] Understandably, the suction cup 211 is designed as a first adsorption area and an outer second adsorption area, and a first adsorption port 2113 and a second adsorption port 2114 are respectively provided to form a partitioned adsorption structure: the first adsorption area is adapted to the flat area in the middle of the wafer, which can quickly achieve stable adsorption; the second adsorption area is adapted to the warped area around the wafer, and even if the edge of the wafer is warped, it can form an effective adsorption force through the independent adsorption port, avoiding wafer displacement caused by adsorption failure, further ensuring the positioning accuracy of the wafer during the calibration process, ensuring uniform force during pressurization and heating, and improving the stability of the overall calibration effect.

[0036] In this embodiment, the distance from the first adsorption port 2113 to the center point is less than 2 / 3 of the radius of the first adsorption zone, and the distance from the second adsorption port 2114 to the center point is less than 2 / 3 of the radius of the second adsorption zone.

[0037] Furthermore, the lower plate assembly 21 also includes a first heat insulation plate 214, a support plate 215, and a second heat insulation plate 216 disposed below the first water cooling plate 213. The support plate 215 is a steel plate, and the first heat insulation plate 214 and the second heat insulation plate 216 are both mica plates.

[0038] Understandably, the mica plate has excellent heat insulation properties, which can effectively block the heat from the first heating plate 212 from being transferred downwards, protecting the components below from high temperatures; the steel plate support plate 215 can improve the overall structural strength and assembly stability of the lower plate assembly 21, avoid uneven wafer stress caused by component deformation during the calibration process, ensure the consistency of calibration accuracy, and extend the service life of the device.

[0039] Furthermore, the lower plate assembly 21 also includes a second water-cooling plate 217 disposed below the second heat insulation plate 216, which further enhances the cooling effect of the lower plate assembly 21 and can prevent the temperature of the lower plate assembly 21 from being transferred to the lower part.

[0040] Furthermore, the upper plate assembly 22 includes a third water-cooling plate 221, a third heat insulation plate 223, and a pressure plate 224 arranged sequentially from bottom to top. The third water-cooling plate 221 can quickly reduce the temperature of the upper plate assembly 22 to prevent overheating of the upper surface of the wafer during the heating process; the third heat insulation plate 223 blocks the upward transfer of heat and protects the upper components such as the drive unit 23.

[0041] Furthermore, the calibration device also includes a connecting seat 4 connected to the upper plate assembly 22 and a leveling component 5 cooperating with the connecting seat 4. The driving component 23 can drive the leveling component 5 to move the upper plate assembly 22 so that the upper plate assembly 22 is parallel to the lower plate assembly 21.

[0042] Understandably, the driving component 23 can drive the leveling component 5 to move the upper plate component 22 to ensure that the upper and lower plate components are parallel, thereby avoiding the problem of excessive local stress and uneven correction of the wafer caused by insufficient parallelism between the upper plate component 22 and the lower plate component 21; through the fine adjustment function of the leveling component 5, assembly errors or structural deformation during operation can be compensated in real time to ensure that the pressure applied by the upper plate component 22 to the wafer is evenly distributed, avoiding local pressure damage or incomplete correction.

[0043] Specifically, the leveling assembly 5 includes a leveling plate 51 connected to the drive unit 23 and a universal adjusting ball 52 mounted on the leveling plate 51. The edge of the leveling plate 51 is connected to the housing 1 via a linear guide rod 53, and the edge of the leveling plate 51 is movably connected to the connecting seat 4. The connecting seat 4 is provided with an adjusting groove 41 adapted to the universal adjusting ball 52. During wafer processing, the drive unit 23 drives the leveling plate 51 to rotate within the adjusting groove 41 via the universal adjusting ball 52 to adjust the parallelism between the leveling plate 51 and the upper plate assembly 22. The movable connection between the leveling plate 51 and the connecting seat 4 provides sufficient freedom for the adjustment of the leveling plate 51, ensuring that the upper plate assembly 22 can quickly adapt to the horizontal state of the lower plate assembly 21. The structure is simple and the adjustment is reliable.

[0044] The above is only one specific implementation of this application, and any other improvements made based on the concept of this application shall be considered within the scope of protection of this application.

Claims

1. A wafer warpage correction device, characterized in that, include: The shell has a cavity; A correction assembly, located within the cavity, is used to correct a warped wafer. It includes a lower plate assembly, an upper plate assembly, and a drive unit connected to the upper plate assembly. The warped wafer can be placed on the lower plate assembly, and the drive unit can drive the upper plate assembly to move toward the lower plate assembly to correct the warped wafer. The lower plate assembly includes a suction cup, a first heating plate located below the suction cup, and a first water-cooling plate. The first heating plate includes a first heating area and a second heating area surrounding the first heating area. The temperature of the first heating area is lower than the temperature of the second heating area. The upper plate assembly includes a second heating plate. The calibration component is configured such that when the wafer is placed on the lower plate assembly, the first heating area heats the central region of the wafer, and the second heating area heats the edge region of the wafer. At the same time, the second heating plate presses against the wafer to maintain pressure on the wafer.

2. The wafer warpage correction device according to claim 1, characterized in that, The suction cup includes a first adsorption area and a second adsorption area surrounding the first adsorption area. The first adsorption area is provided with a plurality of first adsorption ports, and the second adsorption area is provided with a plurality of second adsorption ports.

3. The wafer warpage correction device according to claim 2, characterized in that, The distance from the first adsorption port to the center point is less than 2 / 3 of the radius of the first adsorption zone, and the distance from the second adsorption port to the center point is less than 2 / 3 of the radius of the second adsorption zone.

4. The wafer warpage correction device according to claim 1, characterized in that, The lower plate assembly also includes a first heat insulation plate, a support plate, and a second heat insulation plate disposed below the first water cooling plate. The support plate is a steel plate, and the first and second heat insulation plates are both mica plates.

5. The wafer warpage correction device according to claim 4, characterized in that, The lower plate assembly also includes a second water-cooling plate disposed below the second heat insulation plate.

6. The wafer warpage correction device according to claim 1, characterized in that, The upper plate assembly includes a third water-cooling plate, a third heat insulation plate, and a pressure plate arranged sequentially from bottom to top.

7. The wafer warpage correction device according to claim 6, characterized in that, The temperature of the second heating plate tends to be the same as the temperature of the first heating zone.

8. The wafer warpage correction device according to claim 1, characterized in that, The calibration device further includes a connecting seat connected to the upper plate assembly and a leveling component cooperating with the connecting seat. The driving component can drive the leveling component to move the upper plate assembly so that the upper plate assembly is parallel to the lower plate assembly.

9. The wafer warpage correction device according to claim 8, characterized in that, The leveling assembly includes a leveling plate connected to the drive component and a universal adjusting ball mounted on the leveling plate. The edge of the leveling plate is connected to the housing via a linear guide rod, and the edge of the leveling plate is movably connected to the connecting seat. The connecting seat is provided with an adjusting groove adapted to the universal adjusting ball.

10. The wafer warpage correction apparatus according to any one of claims 1-9, characterized in that, The calibration device also includes a nitrogen assembly connected to the cavity.

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