Polishing solution circulating supply system

Abstract

The utility model provides a circulating polishing solution supply system, which relates to the technical field of semiconductor silicon wafer polishing solution recycling and comprises a circulating solution supply unit, a supply unit, a recovery unit, a recovery pipeline and a supply pipeline, and the circulating solution supply unit at least comprises a polishing solution barrel, a first pipeline and a second pipeline. Wherein the first pipeline is used for connecting a polishing solution barrel and polishing equipment; the second pipeline is used for connecting the polishing liquid barrel and the recovery unit; the recovery unit is connected with polishing equipment through a recovery pipeline; the supply unit is connected with the polishing solution barrel through a plurality of supply pipelines; and the polishing liquid barrel, the first pipeline, the polishing equipment, the recovery pipeline, the recovery unit and the second pipeline are sequentially connected to form a circulation loop. The system has the beneficial effects that the consumable cost can be greatly reduced, the service life of consumables is prolonged, and the product quality is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to semiconductor silicon wafer polishing liquid recycling technical field especially is related to a kind of polishing liquid circulating liquid supply system. BACKGROUND

[0002] Electrochemical polishing process is a kind of stress-free polishing process, for processing ultra-micro feature size semiconductor devices. When electrochemical polishing, chemical reaction is generated by polishing liquid and silicon wafer surface contact to achieve the purpose of polishing, so polishing liquid is an important part of electrochemical polishing process, when object is polished, the surface layer that polishing falls off will be suspended in the form of particle in polishing liquid, while mixed with part of impurities, when the particle in polishing liquid is more, it will affect the normal use of polishing liquid.

[0003] The applicant finds that the prior art at least has the following technical problems:

[0004] The current polishing liquid is generally in the form of direct discharge, i.e. used and discharged immediately, which leads to a large amount of polishing liquid, causing waste and high production cost. UTILITY MODEL CONTENT

[0005] The utility model discloses a kind of polishing liquid circulating liquid supply system, to solve the technical problems that the current polishing liquid in prior art is generally in the form of direct discharge, i.e. used and discharged immediately, which leads to a large amount of polishing liquid, causing waste and high production cost. The preferred technical solutions in many technical solutions provided by the utility model can produce many technical effects, which are described in detail below.

[0006] To achieve the above object, the utility model provides the following technical scheme:

[0007] The utility model provides a kind of polishing liquid circulating liquid supply system, including circulating liquid supply unit, supply unit, recovery unit, recovery pipeline and supply pipeline, the circulating liquid supply unit at least includes polishing liquid barrel, first pipeline and second pipeline, wherein:

[0008] The first pipeline is used to connect the polishing liquid barrel and polishing equipment;

[0009] The second pipeline is used to connect the polishing liquid barrel and the recovery unit;

[0010] The recovery unit is connected with the polishing equipment by the recovery pipeline;

[0011] The supply unit is connected with the polishing liquid barrel by multiple supply pipelines;

[0012] The polishing liquid barrel, the first pipeline, the polishing equipment, the recovery pipeline, the recovery unit, the second pipeline are sequentially connected to form a circulation loop.

[0013] Preferably, the recovery unit comprises a three-way valve and a straight discharge cavity, a sedimentation cavity and a recovery cavity arranged in sequence, wherein:

[0014] The first passage of the three-way valve is connected to the recovery pipeline;

[0015] The second passage of the three-way valve is connected to the straight discharge cavity;

[0016] The third passage of the three-way valve is connected to the sedimentation cavity.

[0017] Preferably, the top of the straight discharge cavity, the sedimentation cavity and the recovery cavity are communicated with each other, a first partition plate is arranged between the straight discharge cavity and the sedimentation cavity, a second partition plate is arranged between the sedimentation cavity and the recovery cavity, and the height of the first partition plate is greater than the height of the second partition plate.

[0018] Preferably, a liquid level sensor is arranged in the recovery cavity.

[0019] Preferably, the polishing liquid circulating supply system further comprises a waste discharge unit, and the straight discharge cavity, the sedimentation cavity, the recovery cavity and the polishing liquid barrel are respectively connected to the waste discharge unit through a waste discharge pipeline.

[0020] Preferably, the supply unit at least comprises a new polishing liquid supply unit, a DIW supply unit and a KOH supply unit, the supply pipeline at least comprises a first supply pipeline connected to the new polishing liquid supply unit, a second supply pipeline connected to the DIW supply unit and a third supply pipeline connected to the KOH supply unit; flow meters and electromagnetic valves are arranged on the first supply pipeline, the second supply pipeline and the third supply pipeline.

[0021] Preferably, a self-circulation pump is arranged in the polishing liquid barrel, and a self-circulation filter element is arranged at the self-circulation pump.

[0022] Preferably, a plurality of sensors are further arranged in the polishing liquid barrel, and the sensors at least comprise a pH sensor, a conductivity sensor and a plurality of liquid level sensors.

[0023] Preferably, the first pipeline is connected to a supply pump, a supply filter element and a flow meter, wherein:

[0024] The supply filter element is arranged between the supply pump and the polishing liquid barrel;

[0025] The flow meter is arranged between the supply filter element and the polishing equipment.

[0026] Preferably, the second pipeline is connected to a recovery pump and a recovery filter element, and the recovery filter element is arranged between the recovery pump and the polishing liquid barrel.

[0027] The polishing liquid circulating supply system provided by the utility model, including circulating supply unit, supply unit, recovery unit, recovery pipeline and supply pipeline, circulating supply unit at least includes polishing liquid barrel, first pipeline and second pipeline, polishing liquid barrel, first pipeline, polishing equipment, recovery pipeline, recovery unit and second pipeline are connected in turn to form circulating loop, so that the polishing liquid waste liquid generated by the polishing equipment can be recovered to the circulating supply unit, and the polishing liquid barrel is supplied according to the preset proportion through the supply unit, so that the mixed liquid in the polishing liquid barrel reaches the various parameter indexes of the polishing liquid and is used again, thus, the consumable cost can be greatly reduced, and the consumable life and product quality are improved. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained according to these drawings without creative labor.

[0029] Figure 1 It is the structure schematic view of one embodiment of the utility model polishing liquid circulating supply system.

[0030] In the drawing: 1, circulating supply unit;10, polishing liquid barrel;101, self-circulation pump;102, self-circulation filter element;103, PH sensor;104, conductivity sensor;105, liquid level sensor;11, first pipeline;111, liquid supply pump;112, liquid supply filter element;12, second pipeline;121, recovery pump;122, recovery filter element;2, supply unit;21, new polishing liquid supply unit;22, DIW supply unit;23, KOH supply unit;3, recovery unit;30, three-way valve;31, direct discharge cavity;32, sedimentation cavity;33, recovery cavity;341, first baffle;342, second baffle;4, recovery pipeline;5, supply pipeline;51, first supply pipeline;52, second supply pipeline;53, third supply pipeline;502, electromagnetic valve;6, polishing equipment;7, waste discharge unit;70, waste discharge pipeline. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantage of the utility model more clear, the technical scheme of the utility model will be described in detail below. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the scope protected by the utility model.

[0032] Figure 1is a structural schematic diagram of the embodiment, as Figure 1 The utility model provides a kind of polishing liquid circulating liquid supply system, including circulating liquid supply unit 1, supply unit 2, recovery unit 3, recovery pipeline 4 and supply pipeline 5.

[0033] Wherein, circulating liquid supply unit 1 at least includes polishing liquid barrel 10, first pipeline 11 and second pipeline 12.First pipeline 11 is used to connect polishing liquid barrel 10 and polishing equipment 6;Second pipeline 12 is used to connect polishing liquid barrel 10 and recovery unit 3;Recovery unit 3 is connected polishing equipment 6 by recovery pipeline 4;Supply unit 2 is connected with polishing liquid barrel 10 by multiple supply pipelines 5;Polishing liquid barrel 10, first pipeline 11, polishing equipment 6, recovery pipeline 4, recovery unit 3, second pipeline 12 are sequentially connected to form circulation loop.

[0034] In the embodiment, first pipeline 11 is connected with liquid supply pump 111, liquid supply filter element 112 and flowmeter, liquid supply filter element 112 is arranged between liquid supply pump 111 and polishing liquid barrel 10, and flowmeter is arranged between liquid supply filter element 112 and polishing equipment 6.Second pipeline 12 is connected with recovery pump 121 and recovery filter element 122, and recovery filter element 122 is arranged between recovery pump 121 and polishing liquid barrel 10.

[0035] Self-circulation pump 101 is arranged in polishing liquid barrel 10, and self-circulation filter element 102 is arranged at self-circulation pump 101.

[0036] Optionally, in some embodiments, automatic control device, such as PLC, can be arranged, so that each valve, pump and sensor is electrically or signal connected with the automatic control device, for realizing automatic control.Liquid level sensor 105 can control the opening of magnetic valve or pump to trigger high or low liquid level protection through control device.

[0037] As an optional implementation, recovery unit 3 includes three-way valve 30 and sequentially arranged direct discharge cavity 31, sedimentation cavity 32 and recovery cavity 33.

[0038] Wherein, the first passage of three-way valve 30 is connected with recovery pipeline 4;The second passage of three-way valve 30 is connected with direct discharge cavity 31;The third passage of three-way valve 30 is connected with sedimentation cavity 32.

[0039] In operation, the polishing liquid discharged by the polishing device 6 is controlled to pass through the recovery pipeline 4 and the three-way valve 30 in sequence, and then discharged into the direct discharge cavity 31 or the sedimentation cavity 32 to be recovered after the large-particle impurities are precipitated.

[0040] Specifically, in the embodiment, the top portions of the direct discharge cavity 31, the sedimentation cavity 32, and the recovery cavity 33 are connected to each other, a first partition plate 341 is arranged between the direct discharge cavity 31 and the sedimentation cavity 32, a second partition plate 342 is arranged between the sedimentation cavity 32 and the recovery cavity 33, and the height of the first partition plate 341 is greater than the height of the second partition plate 342.

[0041] In this way, the overflow channel is formed between the direct discharge cavity 31, the sedimentation cavity 32, and the recovery cavity 33 of the recovery unit 3. In operation, as the liquid level in the sedimentation cavity 32 continuously increases, the polishing liquid after the large-particle impurities are precipitated is overflowed into the recovery cavity 33, so that the automatic precipitation and recovery of the polishing liquid can be realized.

[0042] In addition, in the embodiment, the liquid level sensor 105 is arranged in the recovery cavity 33. When the liquid level in the recovery cavity 33 reaches the height set by the liquid level sensor 105, the recovery pump 121 is triggered to be turned on, and the polishing liquid is recovered into the polishing liquid barrel 10 through the recovery filter element 122.

[0043] As an optional implementation, the polishing liquid circulating and supplying system further comprises a waste discharge unit 7, and the direct discharge cavity 31, the sedimentation cavity 32, the recovery cavity 33, and the polishing liquid barrel 10 are connected to the waste discharge unit 7 through the waste discharge pipeline 70. By arranging the waste discharge pipeline 70 of the recovery unit 3 and the waste discharge pipeline 70 of the circulating and supplying unit 1 respectively, the waste polishing liquid can be discharged for subsequent treatment.

[0044] As an optional implementation, the supplying unit 2 at least comprises a new polishing liquid supplying unit 21, a DIW supplying unit 22, and a KOH supplying unit 23, and the supplying pipeline 5 at least comprises a first supplying pipeline 51 connected to the new polishing liquid supplying unit 21, a second supplying pipeline 52 connected to the DIW supplying unit 22, and a third supplying pipeline 53 connected to the KOH supplying unit 23; the flow meter and the electromagnetic valve 502 are arranged on the first supplying pipeline 51, the second supplying pipeline 52, and the third supplying pipeline 53.

[0045] The working process of the embodiment is as follows:

[0046] The used polishing liquid of the polishing equipment 6 enters the recovery unit 3 through the recovery pipeline 4, and the impurity particles generated in the polishing process are pre-deposited in the recovery unit 3 through the sedimentation cavity 32, so as to reduce the frequency of the recovery filter core 122 blockage, and then enters the recovery cavity 33, and then enters the polishing liquid barrel 10 through the second pipeline 12 and the recovery pump 121; the new polishing liquid of the new polishing liquid supply unit 21 enters the polishing liquid barrel 10 through the first supply pipeline 51 and the electromagnetic valve 502, and the flowmeter is opened according to the preset capacity, such as 20% of the capacity of the polishing liquid barrel 10, to supplement the new polishing liquid in the polishing liquid barrel 10; the new supplemented polishing liquid and the recovered liquid in the polishing liquid barrel 10 are fully mixed through the self-circulation pump 101 and the self-circulation filter core 102 arranged in the polishing liquid barrel 10, and KOH titration is supplemented according to the feedback values of the pH sensor and the conductivity sensor, and after the mixed polishing liquid parameters reach the preset pH value, such as 10.5 pH, and the preset conductivity, such as 4.5, the polishing equipment 6 can be supplied with liquid through the first pipeline 11 to perform polishing processing.

[0047] The above merely illustrates the specific implementation of the present application, but the protection scope of the present application is not limited to this. Any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A polishing slurry circulation supply system, characterized in that, It includes a circulating liquid supply unit, a supply unit, a recovery unit, a recovery pipeline, and a supply pipeline. The circulating liquid supply unit includes at least a polishing liquid tank, a first pipeline, and a second pipeline, wherein: The first pipeline is used to connect the polishing liquid tank and the polishing equipment; The second pipeline is used to connect the polishing liquid tank and the recovery unit; The recycling unit is connected to the polishing equipment via the recycling pipeline; The supply unit is connected to the polishing liquid tank through multiple supply pipelines; The polishing liquid tank, the first pipeline, the polishing equipment, the recovery pipeline, the recovery unit, and the second pipeline are connected in sequence to form a circulation loop.

2. The polishing slurry circulation supply system according to claim 1, characterized in that: The recovery unit includes a three-way valve and a direct discharge chamber, a sedimentation chamber, and a recovery chamber arranged in sequence, wherein: The first passage of the three-way valve is connected to the recovery pipeline; The second passage of the three-way valve is connected to the direct discharge chamber; The third passage of the three-way valve is connected to the sedimentation chamber.

3. The polishing slurry circulation supply system according to claim 2, characterized in that: The tops of the discharge chamber, the sedimentation chamber, and the recovery chamber are interconnected. A first partition is provided between the discharge chamber and the sedimentation chamber, and a second partition is provided between the sedimentation chamber and the recovery chamber. The height of the first partition is greater than the height of the second partition.

4. The polishing slurry circulation supply system according to claim 3, characterized in that: A liquid level sensor is installed inside the recovery chamber.

5. The polishing slurry circulation supply system according to any one of claims 2-4, characterized in that: The polishing slurry circulation supply system also includes a waste discharge unit, and the direct discharge chamber, the sedimentation chamber, the recovery chamber, and the polishing slurry tank are respectively connected to the waste discharge unit through waste discharge pipelines.

6. The polishing slurry circulation supply system according to any one of claims 1-4, characterized in that: The supply unit includes at least a new polishing slurry supply unit, a DIW supply unit, and a KOH supply unit. The supply pipeline includes at least a first supply pipeline connected to the new polishing slurry supply unit, a second supply pipeline connected to the DIW supply unit, and a third supply pipeline connected to the KOH supply unit. Flow meters and solenoid valves are installed on the first supply pipeline, the second supply pipeline, and the third supply pipeline.

7. The polishing slurry circulation supply system according to any one of claims 1-4, characterized in that: The polishing liquid tank is equipped with a self-circulating pump, and the self-circulating pump is equipped with a self-circulating filter element.

8. The polishing slurry circulation supply system according to claim 7, characterized in that: The polishing liquid tank is also equipped with multiple sensors, including at least a pH sensor, a conductivity sensor, and multiple liquid level sensors.

9. The polishing slurry circulation supply system according to any one of claims 1-4 and 8, characterized in that: The first pipeline connects the liquid supply pump, the liquid supply filter element, and the flow meter, wherein: The liquid supply filter element is disposed between the liquid supply pump and the polishing liquid tank; The flow meter is positioned between the liquid supply filter element and the polishing equipment.

10. The polishing slurry circulation supply system according to any one of claims 1-4 and 8, characterized in that, The second pipeline connects the recovery pump and the recovery filter element, which is located between the recovery pump and the polishing liquid tank.

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