A circulating liquid supply system

Abstract

The application discloses a circulating liquid supply system for circulating a polishing liquid of a wafer polishing device, and the circulating liquid supply system comprises a liquid return pipe, a liquid inlet pipe, a height assembly and a polishing liquid container. The liquid inlet end of the liquid return pipe is used for communicating with a polishing liquid collecting groove of the wafer polishing device, and the liquid outlet end of the liquid return pipe is located in the polishing liquid container. The height assembly comprises a height piece, the liquid inlet end of the liquid inlet pipe located in the polishing liquid container is arranged on the top surface of the height piece, the liquid outlet end of the liquid inlet pipe extends to a polishing interface and is used for conveying the polishing liquid to a polishing area, and the bottom surface of the height piece is used for abutting against the bottom surface of the polishing liquid container. According to the technical scheme, the polishing liquid at the bottom of the polishing liquid container can be effectively prevented from being sucked into the liquid inlet pipe, the foreign matters such as particles entering the polishing area through the liquid inlet pipe are greatly reduced, the quality risk of wafer scratch in the polishing process is reduced, and the processing yield is improved.

Description

Technical Field

[0001] This application relates to the field of semiconductor processing technology, and in particular to a circulating liquid supply system. Background Technology

[0002] In existing circulating slurry systems, the inlet pipe is placed inside the polishing slurry container for slurry circulation. However, as the polishing operation continues and the number of cycles increases, particulate impurities gradually accumulate in the polishing slurry. Once these impurities re-enter the circulation system and participate in the polishing process, they can easily cause scratches on the surface of the silicon carbide wafer, severely affecting the polishing quality. Utility Model Content

[0003] This application proposes a circulating fluid supply system to prevent impurities from the used grinding fluid from re-entering the circulating fluid supply, thereby improving the quality of the grinding process.

[0004] To achieve the above objectives, this application discloses the following technical solutions:

[0005] A circulating liquid supply system for circulating polishing slurry in a wafer polishing apparatus, the circulating liquid supply system comprising: a return pipe, an inlet pipe, a height component, and a polishing slurry container;

[0006] The inlet end of the return pipe is used to connect to the polishing slurry collection tank of the wafer polishing device, and the outlet end of the return pipe is located inside the polishing slurry container.

[0007] The height component includes: a height member, wherein the inlet end of the inlet pipe located inside the polishing slurry container is disposed on the top surface of the height member, and the outlet end of the inlet pipe extends to the polishing interface for conveying polishing slurry to the polishing area; the bottom surface of the height member is used to abut against the bottom surface of the polishing slurry container.

[0008] In some embodiments, the height component includes: a height block and a counterweight block;

[0009] The top surface of the height block is provided with the inlet end of the liquid inlet pipe, the bottom surface of the height block is provided on the top surface of the counterweight block, and the bottom surface of the counterweight block is used to abut against the bottom surface of the grinding fluid container.

[0010] In some embodiments, the counterweight is made of at least one of cast iron, lead, or concrete.

[0011] In some embodiments, the height component further includes: a connector with a connection channel; the connector is disposed on the top surface of the height component, and the inlet end of the liquid inlet pipe is connected to the connection channel, and the inlet of the connection channel is connected to the grinding slurry container.

[0012] In some embodiments, the inlet end of the inlet pipe and the outlet end of the return pipe are arranged opposite to each other.

[0013] In some embodiments, the connector is a first connector, which includes a first part, a second part, and a third part arranged sequentially from top to bottom;

[0014] The first part has a vertical through groove, the second part has a recessed side wall forming a groove, the through groove and the groove are connected to form the connecting channel, and the third part is fixed to the height member.

[0015] In some embodiments, the connector is a second connector, which includes a connector block having an L-shaped groove, one opening of the L-shaped groove being located on the top surface of the connector block, the other opening of the L-shaped groove being located on the side surface of the connector block, and the inner wall of the L-shaped groove forming the connector channel.

[0016] In some embodiments, the circulating liquid supply system further includes a circulating pump; the circulating pump is disposed on the inlet pipe to deliver the grinding liquid to the grinding area.

[0017] In some embodiments, the circulating liquid supply system further includes: a filtration device;

[0018] The filtration device includes at least: a first filter screen and a second filter screen that are detachably disposed on the inlet pipe along the liquid outlet direction; the pore size of the first filter screen is smaller than that of the second filter screen.

[0019] In some embodiments, both the return pipe and the inlet pipe are provided with a switch valve, and the inlet pipe is also provided with a flow regulating valve.

[0020] As can be seen from the above technical solution, this circulating liquid supply system effectively prevents the polishing liquid at the bottom of the polishing liquid container from being sucked into the liquid inlet pipe, greatly reduces the entry of foreign objects such as particles into the polishing area through the liquid inlet pipe, reduces the quality risk of wafer scratches during the polishing process, and improves the processing yield. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort, and this application can be applied to other similar scenarios based on the provided drawings, all of which fall within the scope of protection of this utility model. Unless obvious from the linguistic context or otherwise specified, the same reference numerals in the drawings represent the same structure or operation.

[0022] Figure 1 This is an overall schematic diagram of the circulating liquid supply system provided in the embodiments of this application;

[0023] Figure 2 This is a schematic diagram showing the connection between the return pipe, inlet pipe, height component, and grinding fluid container in this circulating liquid supply system;

[0024] Figure 3 This is a schematic diagram showing the fit between the various parts of the first connector in this height assembly;

[0025] Figure 4 This is a schematic diagram showing the cooperation between the second connector and other parts in this height assembly;

[0026] in:

[0027] 10 is the return pipe;

[0028] 20 is the inlet pipe;

[0029] 30 is the height component, 31 is the height block, 32 is the counterweight block, 33 is the first connecting seat, 331 is the first part, 332 is the second part, 333 is the third part, and 34 is the second connecting seat;

[0030] 40 is the polishing slurry container; 50 is the wafer polishing device; 60 is the circulation pump. Detailed Implementation

[0031] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. The described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0032] For the purposes of this application, the following structures are described in detail with reference to the accompanying drawings:

[0033] like Figure 1 and Figure 2 As shown, this application provides a circulating liquid supply system for circulating the polishing slurry of a wafer polishing apparatus. The circulating liquid supply system may include: a return pipe 10, an inlet pipe 20, a height component 30, and a polishing slurry container 40.

[0034] like Figure 2 As shown, the inlet end of the return pipe 10 is used to connect to the polishing slurry collection tank of the wafer polishing apparatus 50, and the outlet end of the return pipe 10 is located inside the polishing slurry container 40.

[0035] The height component 30 may include: a height member, with the inlet end of the inlet pipe 20 located inside the grinding slurry container 40 disposed on the top surface of the height member, and the outlet end of the inlet pipe 20 extending to the grinding interface for conveying the grinding slurry to the grinding area; the bottom surface of the height member is used to abut against the bottom surface of the grinding slurry container 40.

[0036] In the above technical solution, the liquid inlet end of the return pipe 10 is connected to the polishing slurry collection tank of the wafer polishing device 50, and the liquid outlet end of the return pipe 10 is placed in the polishing slurry container 40. Then, the liquid inlet end of the inlet pipe 20 is set on the top surface of the height member, and the height member is placed in the polishing slurry container 40 so that the bottom surface of the height member abuts against the bottom surface of the polishing slurry container 40. During use, the used polishing slurry flows from the polishing slurry collection tank into the polishing slurry container 40 through the return pipe 10. Because the inlet end of the inlet pipe 20 is positioned on a height-adjustable component, a certain distance is maintained between the inlet end of the inlet pipe 20 and the bottom surface of the polishing slurry container 40. This prevents particles and other foreign matter deposited at the bottom of the polishing slurry container 40 from entering the inlet pipe 20 through the inlet end and thus being transported to the polishing area. This effectively prevents the polishing slurry at the bottom of the polishing slurry container 40 from being sucked into the inlet pipe 20, greatly reducing the risk of particles and other foreign matter entering the polishing area through the inlet pipe 20, lowering the quality risk of wafer scratches during the polishing process, and improving processing yield. It also prevents clogging of the inlet pipe 20.

[0037] It should be noted that the height component 30 stabilizes the liquid level at the inlet of the liquid inlet pipe 20, improves the stability of the liquid inlet pipe 20, reduces the circulation of particulate sediment, and improves processing quality.

[0038] To lower the center of gravity of the taller components and make the structure more stable, such as Figure 2 As shown, the height component may include: a height block 31 and a counterweight block 32.

[0039] The top surface of the height block 31 is provided with the inlet end of the liquid inlet pipe 20, and the bottom surface of the height block 31 is located on the top surface of the counterweight block 32. The bottom surface of the counterweight block 32 is used to abut against the bottom surface of the grinding fluid container 40. During use, due to the presence of the counterweight block 32, the height component can quickly sink to the bottom surface of the grinding fluid container 40 under the action of the counterweight block 32.

[0040] Because the manufacturing cost of this circulating fluid supply system needs to be considered, the counterweight 32 is made of at least one of cast iron, lead or concrete, of which cast iron, lead or concrete is inexpensive; in addition, concrete meets the requirements for corrosion resistance.

[0041] To make the connection between the liquid inlet pipe 20 and the height component quicker and easier, such as Figure 1 and Figure 2As shown, the height component 30 also includes: a connecting seat with a connecting channel; the connecting seat is disposed on the top surface of the height component, and the liquid inlet end of the liquid inlet pipe 20 is connected to the connecting channel, and the liquid inlet of the connecting channel is connected to the grinding slurry container 40.

[0042] To ensure that the grinding slurry entering through the inlet pipe 20 is not affected by the outlet end of the return pipe 10, such as Figure 2 and Figure 4 As shown, the inlet end of the liquid inlet pipe 20 and the outlet end of the liquid return pipe 10 are arranged opposite to each other. It can be understood that the inlet end of the liquid inlet pipe 20 faces different directions than the outlet end of the liquid return pipe 10.

[0043] To ensure smoother flow of the grinding fluid, the connecting seat is the first connecting seat, such as... Figure 3 As shown, the first connecting seat 33 may include a first part 331, a second part 332 and a third part 333 arranged sequentially from top to bottom.

[0044] The first part 331 has a vertical through groove, the second part 332 has a recessed side wall forming a groove, the through groove and the groove are connected to form a connecting channel, and the third part 333 is fixed to the height member. In addition, the first connecting seat 33 can be integral or separate.

[0045] like Figure 4 As shown, to ensure smoother flow of the grinding fluid, a second connecting seat 34 is provided. The second connecting seat 34 may include a connecting block with an L-shaped groove. One opening of the L-shaped groove is located on the top surface of the connecting block, and the other opening is located on the side surface of the connecting block. The inner wall of the L-shaped groove forms a connecting channel. This technical solution saves materials and reduces costs. It should also be noted that the connecting channel may be equipped with a quick-connect interface communicating with the inlet pipe 20.

[0046] In order to quickly deliver the grinding fluid and improve work efficiency, such as Figure 1 As shown, the circulating liquid supply system may further include: a circulating pump 60; the circulating pump 60 is disposed on the inlet pipe 20 to deliver the grinding liquid to the grinding area.

[0047] After prolonged use, the inlet pipe 20 may become clogged with impurities. To avoid this problem, the circulating liquid supply system may also include a filter device.

[0048] The filtration device includes at least a first filter screen and a second filter screen, which are detachably mounted sequentially on the inlet pipe 20 along the liquid outlet direction. The pore size of the first filter screen is smaller than that of the second filter screen. In this technical solution, the filter screens can filter impurities in the grinding fluid, ensuring smooth flow during grinding. Furthermore, the filter screens can be replaced at preset time intervals, and the inlet pipe 20 is provided with slots for the filter screens to be snapped into place.

[0049] To control the opening and closing of the return pipe 10 and the inlet pipe 20, both the return pipe 10 and the inlet pipe 20 are equipped with on / off valves. To control the flow rate of the inlet pipe 20, a flow regulating valve is also provided on the inlet pipe 20. Furthermore, the circulating liquid supply system may include a control unit to control the operation of the on / off valves and the flow regulating valve.

[0050] In the above context, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0051] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in this article is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0052] It should be noted that, for ease of description, only the parts relevant to the application are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0053] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed, and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. The scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described application concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A circulating liquid supply system for circulating the polishing slurry in a wafer polishing apparatus, characterized in that, The circulating liquid supply system includes: a return pipe (10), an inlet pipe (20), a height component (30), and a grinding liquid container (40). The inlet end of the return pipe (10) is used to connect to the polishing slurry collection tank of the wafer polishing device (50), and the outlet end of the return pipe (10) is located inside the polishing slurry container (40). The height component (30) includes: a height member, the inlet end of the inlet pipe (20) located in the grinding slurry container (40) is disposed on the top surface of the height member, the outlet end of the inlet pipe (20) extends to the grinding interface, and is used to transport the grinding slurry to the grinding area; the bottom surface of the height member is used to abut against the bottom surface of the grinding slurry container (40).

2. The circulating liquid supply system as described in claim 1, characterized in that, The height component includes: a height block (31) and a counterweight block (32); The top surface of the height block (31) is provided with the inlet end of the liquid inlet pipe (20), the bottom surface of the height block (31) is provided on the top surface of the counterweight block (32), and the bottom surface of the counterweight block (32) is used to abut against the bottom surface of the grinding fluid container (40).

3. The circulating liquid supply system as described in claim 2, characterized in that, The counterweight (32) is made of at least one of cast iron, lead or concrete.

4. The circulating liquid supply system as described in any one of claims 1-3, characterized in that, The height component (30) further includes: a connecting seat with a connecting channel; the connecting seat is disposed on the top surface of the height component, and the liquid inlet end of the liquid inlet pipe (20) is connected to the connecting channel, and the liquid inlet of the connecting channel is connected to the grinding liquid container (40).

5. The circulating liquid supply system as described in claim 4, characterized in that, The inlet end of the inlet pipe (20) and the outlet end of the return pipe (10) are arranged opposite to each other.

6. The circulating liquid supply system as described in claim 5, characterized in that, The connecting seat is a first connecting seat, and the first connecting seat (33) includes: a first part (331), a second part (332) and a third part (333) arranged from top to bottom. The first part (331) has a vertical through groove, the side wall of the second part (332) is recessed to form a groove, the through groove and the groove are connected to form the connecting channel, and the third part (333) is fixed to the height member.

7. The circulating liquid supply system as described in claim 5, characterized in that, The connecting seat is a second connecting seat (34), which includes a connecting block with an L-shaped groove, one opening of the L-shaped groove being located on the top surface of the connecting block, the other opening of the L-shaped groove being located on the side surface of the connecting block, and the inner wall of the L-shaped groove forming the connecting channel.

8. The circulating liquid supply system according to any one of claims 1-3, characterized in that, The circulating liquid supply system further includes a circulating pump (60); the circulating pump (60) is disposed on the inlet pipe (20) to deliver the grinding liquid to the grinding area.

9. The circulating liquid supply system according to any one of claims 1-3, characterized in that, The circulating liquid supply system also includes: a filtration device; The filtration device includes at least a first filter screen and a second filter screen that are detachably disposed on the inlet pipe (20) in sequence along the liquid outlet direction; the pore size of the first filter screen is smaller than that of the second filter screen.

10. The circulating liquid supply system according to any one of claims 1-3, characterized in that, Both the return pipe (10) and the inlet pipe (20) are equipped with switching valves, and the inlet pipe (20) is also equipped with a flow regulating valve.

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