Transfer mechanism for thinned bonded wafer

Abstract

The application discloses a kind of transfer mechanisms for thinned bonded wafers, and it relates to the technical field of semiconductor transfer.The thinned bonded wafer includes a first wafer and a second wafer connected by bonding, one side of the first wafer facing the second wafer forms a cavity, and the first wafer also includes a thinned surface away from the second wafer.The suction unit of the transfer mechanism is located at the end of the mechanical arm, and the suction unit includes a plurality of spaced distribution through holes in communication with the vacuum pump.The buffer unit is detachably mounted at the bottom of the suction unit, and the buffer unit includes a first area corresponding to the cavity in the first wafer and a second area corresponding to the solid part in the first wafer.The first area and the second area both have a plurality of suction holes in communication with the through holes, and the porosity of the first area is less than that of the second area.The transfer mechanism of the present application can provide flexible buffering effect for the thinned bonded wafer, prevent it from being damaged during transfer, and thus improve the transfer yield of the thinned bonded wafer.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor transfer technology, specifically to a transfer mechanism for thinning bonded wafers. Background Technology

[0002] In wafer backside thinning equipment, vacuum ceramic chucks are used to pick up and transfer the wafers between different mechanisms. When the wafers have cavities after bonding in the thinning equipment, the vacuum ceramic chucks pick up the wafers and use this suction to transport them to the cleaning mechanism for cleaning. Because the backside of the freshly processed wafers is contaminated, the direct suction of the wafers by the vacuum ceramic chucks can damage the cavities in the thinned wafers, rendering them unusable and preventing further manufacturing processes.

[0003] In existing technologies, after the thinned bonding wafer is processed by a wafer thinning device, the gripping method of the robotic arm is modified, that is, the vacuum ceramic chuck is transformed into a physical gripping method, which grips the edge of the wafer to prevent damage to the cavities on the bonding wafer. However, the method of gripping and transporting the thinned bonding wafer by gripping its edge is unstable, prone to gripping failure leading to equipment alarms, and has high modification and maintenance costs. Utility Model Content

[0004] One objective of this invention is to provide a transfer mechanism for thinned bonded wafers, which solves the technical problems of easy breakage or unstable transfer method of thinned bonded wafers during vacuum transfer in the prior art.

[0005] Another objective of this invention is to improve the structural stability and reliability of the adsorption process.

[0006] According to the purpose of this utility model, this utility model provides a transfer mechanism for thinned bonding wafers, wherein the thinned bonding wafers include a first wafer and a second wafer bonded together, a cavity is formed on the side of the first wafer facing the second wafer, and the first wafer also includes a thinned surface away from the second wafer, and the transfer mechanism includes:

[0007] An adsorption unit, located at the end of a robotic arm, includes a plurality of spaced-apart through holes connected to a vacuum pump.

[0008] A buffer unit is detachably installed at the bottom of the adsorption unit. The buffer unit includes a first region corresponding to the cavity in the first wafer and a second region corresponding to the solid portion in the first wafer. Both the first region and the second region have multiple adsorption holes communicating with the through hole, and the porosity of the first region is less than that of the second region.

[0009] Optionally, the buffer unit further includes:

[0010] A connecting layer is located on the periphery of the buffer unit near the adsorption unit, and the connecting layer is used to connect the buffer unit and the adsorption unit.

[0011] Optionally, the connecting layer is made of either thermoplastic elastomer or thermoplastic polyurethane elastomer.

[0012] Optionally, the buffer unit and the adsorption unit are magnetically connected.

[0013] Optionally, the material of the buffer unit can be any one of silicone rubber, non-woven fabric, or polypropylene foam.

[0014] Optionally, the thickness of the buffer unit is any value between 0.5mm and 2.0mm.

[0015] Optionally, the pore diameter of the adsorption pore of the buffer unit is any value between 0.1 mm and 5.0 mm.

[0016] Optionally, the diameter of the buffer unit is any value between 100mm and 200mm.

[0017] Optionally, the transfer mechanism further includes:

[0018] A vacuum tube is located between the adsorption unit and the vacuum pump. The vacuum tube includes a threaded quick-connect fitting that is sealed to the adsorption unit, and an O-ring is provided inside the threaded quick-connect fitting.

[0019] Furthermore, by setting a buffer unit at the bottom of the adsorption unit, and setting adsorption pores with different porosities in the buffer unit for the cavity area and solid area of ​​the thinned bonded wafer respectively, the negative pressure stress in the cavity area can be effectively buffered during vacuum adsorption to prevent cavity damage. The setting of the buffer unit can also isolate crystal slag and crystal mud contamination on the back of the thinned bonded wafer, preventing contaminants from clogging the adsorption pores or entering the cavity, improving the cleanliness and stability of the adsorption process, and also improving the handling yield of the thinned bonded wafer without affecting the vacuum adsorption efficiency.

[0020] Furthermore, the connecting layer of this invention is disposed in the peripheral area of ​​the buffer unit near the adsorption unit, and is used to stably connect the buffer unit to the adsorption unit. This connecting layer can ensure that the buffer unit does not loosen or shift during vacuum adsorption and thinning bonding wafer handling, thereby improving the structural stability and reliability of the adsorption process.

[0021] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0022] The following sections will describe some specific embodiments of the present invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or components. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0023] Figure 1 This is a schematic structural diagram of a transfer mechanism according to an embodiment of the present utility model;

[0024] Figure 2 This is a schematic structural diagram of a buffer unit according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic structural diagram of a thinned bonding wafer according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic structural diagram of a buffer unit according to another embodiment of the present invention.

[0027] Figure label:

[0028] 100-Transfer mechanism, 200-Thinned bonding wafer, 10-First wafer, 20-Adsorption unit, 21-Through hole, 30-Buffer unit, 11-Cavity, 31-First region, 12-Solid part, 32-Second region, 33-Connecting layer, 34-Adsorption hole. Detailed Implementation

[0029] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0031] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] like Figure 1 As shown, this utility model provides a thinned bonding wafer 200 (refer to...). Figure 3 The transfer mechanism 100 is used. The thinned bonding wafer 200 includes a first wafer 10 bonded together (see reference). Figure 3 The first wafer 10 has a cavity 11 formed on the side facing the second wafer, and the first wafer 10 also includes a thinned surface away from the second wafer.

[0034] like Figure 1 As shown, in this embodiment, the transfer mechanism 100 includes an adsorption unit 20 and a buffer unit 30. The adsorption unit 20 is located at the end of the robotic arm and includes a plurality of spaced-apart through holes 21 communicating with a vacuum pump. The buffer unit 30 is detachably mounted on the bottom of the adsorption unit 20 and includes a first region 31 corresponding to the cavity 11 in the first wafer 10 and a second region 32 corresponding to the solid portion 12 in the first wafer 10. Both the first region 31 and the second region 32 have a plurality of adsorption holes 34 communicating with the through holes 21, and the porosity of the first region 31 is less than that of the second region 32. Here, the plurality of through holes 21 are evenly distributed in the adsorption unit 20 to ensure that the adsorption force of the adsorption unit 20 is evenly distributed after the vacuum pump is evacuated. Here, the thickness of the first wafer 10 is any value between 60μm and 100μm, that is, the thickness of the thinned wafer can be 60μm, 70μm, 80μm, 90μm or 100μm, or any value between 60μm and 100μm.

[0035] like Figure 2As shown, in this embodiment, by setting a buffer unit 30 at the bottom of the adsorption unit 20, and setting adsorption holes 34 with different porosities in the buffer unit 30 for the cavity 11 region and the solid region of the thinned bonded wafer 200 respectively, the negative pressure stress in the cavity 11 region can be effectively buffered during vacuum adsorption, preventing the cavity 11 from being damaged. The setting of the buffer unit can also isolate the crystal slag and crystal mud contamination on the back of the thinned bonded wafer 200, preventing contaminants from clogging the adsorption holes 34 or entering the cavity 11, improving the cleanliness and stability of the adsorption process, and also improving the handling yield of the thinned bonded wafer 200 without affecting the vacuum adsorption efficiency.

[0036] In this embodiment, a buffer unit 30 is provided on the side of the adsorption unit 20 close to the thinned bonded wafer 200 to provide a flexible buffer when the adsorption unit 20 adsorbs the thinned bonded wafer 200. This prevents the residual crystal slag or crystal mud on the surface of the thinned bonded wafer 200 from directly contacting the rigid adsorption unit 20, and prevents the crystal slag or crystal mud from generating negative compressive stress on the thinned back side of the thinned bonded wafer 200 under the adsorption action, thereby preventing the cavity 11 from collapsing and ensuring the structural integrity of the thinned bonded wafer 200.

[0037] In this embodiment, by setting the buffer unit 30 as a detachable installation structure, the buffer unit 30 can be adjusted or replaced according to the wafer or cavity 11 area shape of different specifications, which facilitates maintenance or adaptation to different process requirements and improves the versatility and maintainability of the transfer mechanism 100.

[0038] like Figure 4 As shown, in a further embodiment, the buffer unit 30 further includes a connecting layer 33. The connecting layer 33 is disposed in the peripheral area of ​​the buffer unit 30 near the adsorption unit 20 and is used to stably connect the buffer unit 30 to the adsorption unit 20. This connecting layer 33 ensures that the buffer unit 30 does not loosen or shift during vacuum adsorption and handling of the thinned bonded wafer 200, improving the structural stability and reliability of the adsorption process. Simultaneously, the connecting layer 33 structure facilitates quick disassembly and replacement, is suitable for the process transport needs of different types of wafers, and prevents adhesion and contamination, contributing to improved cleanliness of the adsorption unit 20 and continuous equipment operation.

[0039] In a further embodiment, the connecting layer 33 is made of either a thermoplastic elastomer or a thermoplastic polyurethane elastomer. In this embodiment, the thermoplastic elastomer or thermoplastic polyurethane elastomer possesses good elasticity, wear resistance, and adhesion properties. When the connecting layer 33 is made of any of these materials, it provides a stable and reliable connection when the buffer unit 30 is installed onto the adsorption unit 20, preventing loosening or misalignment during transport. Simultaneously, the thermoplastic elastomer or thermoplastic polyurethane elastomer material also exhibits excellent chemical resistance and cleanliness, suitable for the high-cleanliness environment requirements of semiconductor wafer transport, and supports rapid disassembly and reuse, improving equipment maintenance efficiency and adaptability.

[0040] In a further embodiment, a permanent magnet or embedded magnetic element is provided in the bottom or near-bottom plane of the adsorption unit 20, and a magnetically attractive structure is provided on the side of the buffer unit 30 near the adsorption unit 20. This allows the magnetic element and the magnetic attraction structure to be aligned and magnetically attracted, achieving a stable connection between the buffer unit 30 and the adsorption unit 20 without the need for screws, adhesives, or other similar methods. In other words, by providing a magnetic connection structure between the adsorption unit 20 and the buffer unit 30, a stable and detachable connection between the buffer unit 30 and the adsorption unit 20 is achieved, avoiding the problems of contamination or inconvenience in disassembly and assembly caused by using adhesives or threaded parts.

[0041] In a further embodiment, the buffer unit 30 can be made of any one of silicone rubber, non-woven fabric, or polypropylene foam. In this embodiment, silicone rubber, non-woven fabric, and polypropylene foam materials possess good flexibility, cushioning performance, and moderate air permeability, effectively mitigating the risk of damage to the bonding cavity 11 caused by adsorption forces during the handling of the thinned bonded wafer 200, while not affecting the transmission of vacuum adsorption forces. The buffer unit 30 materials described above also possess characteristics of wear resistance, contamination resistance, or high replaceability, allowing for flexible selection according to process requirements and improving the overall stability of the adsorption system.

[0042] In a further embodiment, the thickness of the buffer unit 30 is any value between 0.5mm and 2.0mm, that is, the thickness of the buffer unit 30 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.2mm, 1.5mm, or 2.0mm, or any value between 0.5mm and 2.0mm. In this embodiment, the buffer unit 30 with the above-mentioned thickness can ensure sufficient buffering effect without affecting the transmission of vacuum adsorption force, which is beneficial to protecting the cavity 11 structure in the thinned bonding wafer 200 and preventing it from breaking due to stress impact during adsorption and transfer. At the same time, this thickness range is convenient for matching wafer products with different thicknesses and structural shapes, improving equipment adaptability and process yield.

[0043] In a further embodiment, the aperture of the adsorption hole 34 of the buffer unit 30 is any value between 0.1 mm and 5.0 mm. That is, the aperture of the adsorption hole 34 of the buffer unit 30 can be 0.1 mm, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, or 5.0 mm, or any value between 0.1 mm and 5.0 mm. In this embodiment, the adsorption hole 34 of the buffer unit 30 within the above aperture range can ensure the effective transmission and uniform distribution of vacuum adsorption force, and also help alleviate local stress concentration during the adsorption process, reducing the risk of damage to the cavity 11 structure of the thinned bonded wafer 200.

[0044] In a further embodiment, the diameter of the buffer unit 30 is any value between 100mm and 200mm, that is, the diameter of the buffer unit 30 can be 100mm, 120mm, 140mm, 160mm, 180mm, or 200mm, or any value between 100mm and 200mm. In this embodiment, the buffer unit 30 within the above-mentioned size range helps to ensure the complete coverage of the back side of the thinned bonded wafer 200 by the adsorption unit 20 and the uniformity of the adsorption force distribution, thereby improving the stability and safety of the thinned bonded wafer 200 during handling.

[0045] In a further embodiment, the transfer mechanism 100 also includes a vacuum tube located between the adsorption unit 20 and the vacuum pump. The vacuum tube is sealed to the adsorption unit 20 via a threaded quick-connect fitting at one end. An O-ring is provided inside the threaded quick-connect fitting, which fits snugly against the adsorption unit 20 to form a reliable seal at the connection point. This ensures that the negative pressure generated by the vacuum pump can be stably transmitted to the adsorption unit 20, achieving vacuum adsorption of the thinned bonded wafer 200. In this embodiment, the structure of the vacuum tube effectively improves the sealing performance and connection stability between the adsorption unit 20 and the vacuum tube, preventing leakage or detachment during vacuum adsorption, ensuring the safety and reliability of the thinned bonded wafer 200 handling process, facilitating quick disassembly and subsequent maintenance, and improving the overall operating efficiency.

[0046] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A transfer mechanism for thinning bonded wafers, characterized in that, The thinned bonding wafer includes a first wafer and a second wafer bonded together. A cavity is formed on the side of the first wafer facing the second wafer. The first wafer also includes a thinned surface away from the second wafer. The transfer mechanism includes: An adsorption unit, located at the end of a robotic arm, includes a plurality of spaced-apart through holes connected to a vacuum pump. A buffer unit is detachably installed at the bottom of the adsorption unit. The buffer unit includes a first region corresponding to the cavity in the first wafer and a second region corresponding to the solid portion in the first wafer. Both the first region and the second region have multiple adsorption holes communicating with the through hole, and the porosity of the first region is less than that of the second region.

2. The transfer mechanism according to claim 1, characterized in that, The buffer unit further includes: A connecting layer is located on the periphery of the buffer unit near the adsorption unit, and the connecting layer is used to connect the buffer unit and the adsorption unit.

3. The transfer mechanism according to claim 2, characterized in that, The connecting layer is made of either thermoplastic elastomer or thermoplastic polyurethane elastomer.

4. The transfer mechanism according to claim 1, characterized in that, The buffer unit and the adsorption unit are magnetically connected.

5. The transfer mechanism according to claim 4, characterized in that, The material of the buffer unit can be any one of silicone rubber, non-woven fabric or polypropylene foam.

6. The transfer mechanism according to claim 5, characterized in that, The thickness of the buffer unit is any value between 0.5mm and 2.0mm.

7. The transfer mechanism according to any one of claims 1-6, characterized in that, The pore diameter of the adsorption pore of the buffer unit is any value between 0.1 mm and 5.0 mm.

8. The transfer mechanism according to claim 7, characterized in that, The diameter of the buffer unit is any value between 100mm and 200mm.

9. The transfer mechanism according to claim 8, characterized in that, Also includes: A vacuum tube is located between the adsorption unit and the vacuum pump. The vacuum tube includes a threaded quick-connect fitting that is sealed to the adsorption unit, and an O-ring is provided inside the threaded quick-connect fitting.

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