Wafer backgrinding device

Abstract

The utility model belongs to the technical field of grinding device, especially for a kind of wafer crystal back grinding device, including providing stable support pedestal, being in the pedestal upper and being used to place the grinding table of wafer, be located the upper of grinding table and be used to polish the wafer placed on grinding table's grinding assembly and be used to cool the cooling liquid drop infusion component in the wafer of grinding process, the recess for accommodating cooling liquid is opened in the upper surface of the grinding table, the cooling liquid drop infusion component has first liquid outlet pipe and second liquid outlet pipe, the first liquid outlet pipe is used to carry out cooling liquid drop infusion to the upper central position of wafer, the second liquid outlet pipe is communicated with recess and passes through the central position of grinding table, the second liquid outlet pipe is rotatably connected with grinding table, it can better cool and cool its upper surface and lower surface in the wafer grinding process by setting first liquid outlet pipe and second liquid outlet pipe, avoid error to appear in processing process.

Description

Technical Field

[0001] This utility model belongs to the technical field of grinding equipment, specifically relating to a wafer back-grinding device. Background Technology

[0002] Wafer grinding equipment is a core piece of equipment in semiconductor manufacturing and packaging processes. It is mainly used for precision machining of the surface or back of wafers to achieve key objectives such as thickness control, flatness optimization, and surface quality improvement. The specific grinding process involves placing the wafer on a grinding table, where the table's rotation and the grinding disc's rotation grind the wafer. During grinding, to prevent overheating in localized grinding areas, coolant is sprayed from above the grinding table to cool the wafer. However, existing cooling methods only cool the upper surface of the wafer, resulting in temperature inconsistencies between the upper and lower surfaces. This can easily cause wafer bending (different temperatures lead to different expansion and deformation, resulting in slight bending similar to a bimetallic sheet), leading to deviations in the processing. Utility Model Content

[0003] To address the above problems, the purpose of this utility model is to provide a wafer back-grinding device to solve the problems mentioned in the background art.

[0004] This invention provides a wafer back-end polishing device, which, by setting a first liquid outlet pipe and a second liquid outlet pipe, can better cool and reduce the temperature of the upper and lower surfaces of the wafer during the polishing process, thus avoiding errors in the processing.

[0005] The technical problem solved by this utility model is achieved by the following technical solution: A wafer back-grinding apparatus includes a base providing stable support, a grinding table above the base for placing a wafer, a grinding assembly above the grinding table for grinding the wafer placed on the grinding table, and a coolant dripping assembly for cooling the wafer during the grinding process. The upper surface of the grinding table has a groove for receiving coolant. The coolant dripping assembly has a first outlet pipe and a second outlet pipe. The first outlet pipe is used to drip coolant onto the center position above the wafer. The second outlet pipe passes through the center of the grinding table and communicates with the groove. The second outlet pipe is rotatably connected to the grinding table.

[0006] Preferably, the edge of the grinding table is provided with a protrusion to prevent the wafer from slipping off, and the protrusion has an opening.

[0007] Preferably, the groove is a plurality of concentric rings, wherein the innermost ring-shaped groove is connected to the output end of the second liquid outlet pipe, and the plurality of ring-shaped grooves are connected to each other through channels.

[0008] Preferably, the channels between the plurality of annular grooves are on the same straight line.

[0009] Preferably, the channels between the plurality of annular grooves are arranged in an alternating manner.

[0010] Preferably, the groove is spiral in shape, and the water inlet end of the groove is connected to the output end of the second liquid outlet pipe.

[0011] The beneficial effects of this utility model are: by setting a first liquid outlet pipe and a second liquid outlet pipe, the upper and lower surfaces of the wafer can be cooled down better during the wafer grinding process, thus avoiding errors in the processing. Attached Figure Description

[0012] Figure 1 This is a first three-dimensional structural diagram of the present invention; Figure 2 This is a first side view of the structure of this utility model; Figure 3 This is a first sectional view of the present invention; Figure 4 This is a partial top view schematic diagram of the structure of this utility model; Figure 5 This is a schematic diagram of the structure of the first embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the second embodiment of the present invention; Figure 7 This is a schematic diagram of the third embodiment of the present invention.

[0013] In the diagram: 1. Base; 2. Grinding table; 3. Grinding disc; 4. First motor; 5. First outlet pipe; 6. First water pump; 7. Second water pump; 8. Water tank; 9. Second motor; 10. Second gear; 11. First gear; 12. Opening; 13. Groove; 14. Channel; 15. Second outlet pipe. Detailed Implementation

[0014] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of this utility model in any way.

[0015] An existing wafer back-grinding device mainly includes a base 1 providing stable support, a grinding table 2 (rotatably connected to the base 1) for placing the wafer and preventing it from slipping during processing, a grinding assembly for grinding the wafer placed on the grinding table 2, and a coolant dripping assembly for the wafer during the grinding process. In use, the wafer is placed on the grinding table 2, and a grinding disc 3 on the grinding assembly is held tightly against the wafer by a telescopic rod. A first motor 4 on the grinding assembly drives the grinding disc 3 to rotate. A first gear 11, under the rotational power of a second motor 9, drives a second gear 10 to rotate. The second gear 10 is connected to the grinding table 2, thus rotating the grinding table 2 and grinding the wafer. During the grinding process, heat is generated due to friction between the grinding disc 3 and the wafer. The coolant in the water tank 8 is drawn from the first water pump 6 on the cooling drip assembly and dripped onto the upper surface of the wafer to cool the friction surface and clean the debris during the polishing process. After the upper surface is polished, the wafer is flipped over and the above actions are repeated to polish the lower surface of the wafer. The above is the working process of a conventional wafer back-end polishing device. The problem with the conventional wafer back-end polishing device is that, during the polishing process, the polishing area of ​​the wafer may overheat. The cooling drip assembly only cools the upper surface of the wafer, which results in the temperature of the upper and lower surfaces of the wafer not being consistent. This leads to problems such as bending and deformation of the wafer during the polishing process. Therefore, the conventional wafer back-end polishing device cannot achieve the best polishing effect during the polishing process.

[0016] Based on the above problems, the present invention adopts the following improvement method to solve them.

[0017] like Figure 1-4As shown, a wafer back-end polishing apparatus includes a base 1 providing stable support, a polishing table 2 positioned above the base 1 for placing the wafer, a polishing assembly positioned above the polishing table 2 for polishing the wafer placed on the polishing table 2, and a coolant dripping assembly for cooling the wafer during the polishing process. The upper surface of the polishing table 2 has a groove 13 for receiving coolant. The coolant dripping assembly has a first outlet pipe 5 and a second outlet pipe 15. The first outlet pipe 5 drips coolant onto the center of the wafer, and the second outlet pipe 15 penetrates the center of the polishing table 2 and communicates with the groove 13. The second outlet pipe 15 is rotatably connected to the polishing table 2 (relative rotatable connection can be achieved through existing sealed bearings). The present invention is similar to the existing wafer back-end polishing apparatus in that it includes a base 1, a polishing table 2, a polishing assembly, and a coolant dripping assembly. The difference lies in the addition of the groove 13 and the second outlet pipe 15. By setting the groove 13 and the second outlet pipe 15, the wafer can be more fully polished during the polishing process. The cooling process involves placing the wafer on the grinding table 2, then using the grinding disc 3 on the grinding assembly to press it tightly against the wafer via a telescopic rod. The first motor 4 on the grinding assembly drives the grinding disc 3 to rotate. The first gear 11, under the rotational power of the second motor 9, drives the second gear 10 to rotate, and the second gear 10 is connected to the grinding table 2, allowing the grinding table 2 to rotate relative to the base 1, thus grinding the wafer. During grinding, heat and debris are generated due to friction between the grinding disc 3 and the wafer. The first water pump 6 on the cooling drip assembly draws coolant from the water tank 8 and drips it onto the upper surface of the wafer, cooling the friction surface and cleaning debris generated during grinding. The second water pump 7 on the coolant assembly draws coolant from the water tank 8 to cool the lower surface of the wafer. After grinding the upper surface, the wafer is flipped over, and the above actions are repeated to continue grinding the lower surface. Compared to existing technologies, this invention achieves the effect of avoiding errors caused by overheating during wafer grinding, resulting in better cooling.

[0018] Furthermore, such as Figure 1-5 As shown, the edge of the grinding table 2 is provided with a protrusion to prevent the wafer from slipping. The protrusion has an opening 12. By providing a protrusion on the edge of the grinding table 2, the wafer is clamped and fixed when placed on the grinding table 2, preventing it from slipping during the grinding process. By providing an opening 12 at the position of the protrusion, it is more convenient and faster to pick up and put down the wafer, and the coolant discharged from the second liquid outlet pipe 15 flows out of the grinding table 2 through the opening 12.

[0019] Furthermore, such as Figure 5-6As shown, the groove 13 is shaped as multiple concentric rings, with the innermost ring groove 13 connected to the output end of the second liquid outlet pipe 15. The multiple ring grooves 13 are connected through channels 14. By setting the groove 13 as multiple concentric rings, with the innermost groove 13 connected to the second liquid outlet pipe 15 and the multiple rings connected through channels 14, the second liquid outlet pipe 15 can fill the multiple concentric rings with coolant through channels 14 when discharging coolant, thereby cooling the lower surface of the wafer during the polishing process.

[0020] Furthermore, such as Figure 5-6 As shown, the channels 14 between the multiple annular grooves 13 are on the same straight line. By setting the channels 14 between the grooves 13 to be on the same straight line, the coolant can be filled into each annular groove 13 more directly, thereby cooling the lower surface of the wafer during the polishing process.

[0021] Furthermore, such as Figure 6 As shown, the channels 14 between the multiple annular grooves 13 are arranged in an alternating manner. By setting the channels 14 between the grooves 13 to be interlaced, the channels 14 are arranged in an alternating manner so that the coolant fills each annular groove 13 in sequence, thereby cooling the lower surface of the wafer during the polishing process.

[0022] Furthermore, such as Figure 7 As shown, the groove 13 is spiral in shape. The water inlet of the groove 13 is connected to the output end of the second liquid outlet pipe 15. By setting the groove 13 to be spiral and connecting the water inlet of the groove 13 to the output end of the second liquid outlet pipe 15, the second liquid outlet pipe 15 can rotate and fill the groove 13 through the spiral groove when discharging coolant, thereby cooling the lower surface of the wafer during the polishing process.

[0023] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Specific examples have been used in this document to illustrate the principles and implementation methods of this utility model. The above examples are merely to aid in understanding the method and core ideas of this utility model. The above descriptions are only preferred embodiments of this utility model. It should be pointed out that, due to the limitations of written expression, there are objectively infinite specific structures. For those skilled in the art, several improvements, modifications, or variations can be made without departing from the principles of this utility model, and the above technical features can be combined in an appropriate manner. These improvements, modifications, variations, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this utility model.

Claims

1. A wafer back-end polishing apparatus, comprising a base (1) providing stable support, a polishing table (2) positioned above the base (1) for placing a wafer, a polishing assembly positioned above the polishing table (2) for polishing the wafer placed on the polishing table (2), and a cooling liquid dispensing assembly for cooling the wafer during the polishing process, characterized in that: The upper surface of the grinding table (2) is provided with a groove (13) for containing coolant. The coolant dripping assembly has a first outlet pipe (5) and a second outlet pipe (15). The first outlet pipe (5) is used to drip coolant onto the center position above the wafer. The second outlet pipe (15) passes through the center position of the grinding table (2) and communicates with the groove (13). The second outlet pipe (15) is rotatably connected to the grinding table (2).

2. The wafer back-end polishing apparatus according to claim 1, characterized in that: The edge of the grinding table (2) is provided with a protrusion to prevent the wafer from slipping off, and the protrusion has an opening (12).

3. The wafer back-end polishing apparatus according to claim 1, characterized in that: The groove (13) is in the shape of multiple concentric rings, wherein the innermost ring groove (13) is connected to the output end of the second liquid outlet pipe (15), and the multiple ring grooves (13) are connected to each other through a channel (14).

4. The wafer back-end polishing apparatus according to claim 3, characterized in that: The channels (14) between the multiple annular grooves (13) are on the same straight line.

5. The wafer back-end polishing apparatus according to claim 3, characterized in that: The channels (14) between the multiple annular grooves (13) are arranged in an alternating manner.

6. The wafer back-end polishing apparatus according to claim 1, characterized in that: The groove (13) is spiral in shape, and the water inlet end of the groove (13) is connected to the output end of the second liquid outlet pipe (15).

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