CN115505339A - Recycling method of coarse polishing solution - Google Patents
Recycling method of coarse polishing solution Download PDFInfo
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- CN115505339A CN115505339A CN202211346937.5A CN202211346937A CN115505339A CN 115505339 A CN115505339 A CN 115505339A CN 202211346937 A CN202211346937 A CN 202211346937A CN 115505339 A CN115505339 A CN 115505339A
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- polishing
- solution
- rough polishing
- recovered
- rough
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- 238000005498 polishing Methods 0.000 title claims abstract description 178
- 238000004064 recycling Methods 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 33
- 239000000243 solution Substances 0.000 claims abstract description 133
- 238000011084 recovery Methods 0.000 claims abstract description 30
- 239000011550 stock solution Substances 0.000 claims abstract description 25
- 238000002360 preparation method Methods 0.000 claims abstract description 23
- 238000007517 polishing process Methods 0.000 claims abstract description 21
- 238000001914 filtration Methods 0.000 claims abstract description 19
- 238000007518 final polishing process Methods 0.000 claims abstract description 19
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 15
- 229910052710 silicon Inorganic materials 0.000 claims description 15
- 239000010703 silicon Substances 0.000 claims description 15
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 11
- 239000000654 additive Substances 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 6
- 239000000758 substrate Substances 0.000 claims description 6
- 230000000996 additive effect Effects 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 239000002738 chelating agent Substances 0.000 claims description 3
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- 229920000642 polymer Polymers 0.000 claims description 3
- 230000001502 supplementing effect Effects 0.000 claims description 3
- 239000002699 waste material Substances 0.000 abstract description 5
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09G—POLISHING COMPOSITIONS; SKI WAXES
- C09G1/00—Polishing compositions
- C09G1/06—Other polishing compositions
- C09G1/14—Other polishing compositions based on non-waxy substances
- C09G1/18—Other polishing compositions based on non-waxy substances on other substances
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Grinding-Machine Dressing And Accessory Apparatuses (AREA)
Abstract
The invention provides a method for recycling a rough polishing solution, which comprises the following steps: step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin; step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain recovered coarse polishing solution; and step S3: filtering the recovered rough polishing solution for the first time, and transmitting the recovered rough polishing solution to a second recovery barrel; and step S4: and filtering the recovered rough polishing solution for the second time, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process, so that the rough polishing solution of the final polishing process is recovered and reused, the waste of the polishing solution is reduced, and the cost is saved.
Description
Technical Field
The invention relates to the field of semiconductor manufacturing, in particular to a method for recycling rough polishing solution used for a final polishing process.
Background
The polishing process of the silicon wafer surface mainly comprises two processes of a double-sided polishing process and a final polishing process. In the double-sided polishing process, a double-sided polishing machine table mainly comprises a machine table body, an upper fixed disc and a lower fixed disc, wherein polishing pads are attached to the upper fixed disc and the lower fixed disc, rough polishing liquid is introduced into the upper fixed disc, and the purpose of double-sided polishing of a silicon wafer is achieved through the movement of the upper fixed disc, the lower fixed disc and the silicon wafer, namely the surface defect of the silicon wafer caused by the preorder process is removed, and the requirement on the surface flatness of the silicon wafer is met. Wherein, the rough polishing solution used in the double-side polishing process can be recycled.
In the final polishing process, the final polishing process comprises two process steps of a rough polishing process and a fine polishing process, the rough polishing process mainly aims to remove slight scratches on the surface of the silicon wafer caused by the previous process, and the roughness of the surface of the silicon wafer can be reduced, and the rough polishing solution is also used in the process. The purpose of the fine polishing process is mainly to further reduce the roughness of the silicon wafer surface and ensure the particle level of the silicon wafer surface, and the fine polishing solution is used in the process. The polishing solutions (i.e., the rough polishing solution and the fine polishing solution) used in the final polishing are all in-line, so that the rough polishing solution cannot be recycled, and the rough polishing solutions finally enter a sewage treatment system for treatment, thereby causing the waste of the polishing solutions.
Disclosure of Invention
The invention aims to provide a method for recycling a coarse polishing solution, which can recycle the coarse polishing solution in a final polishing process so as to reduce the waste of the polishing solution.
In order to solve the above problems, the present invention provides a method for recycling a rough polishing solution, comprising the steps of:
step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin;
step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain recovered coarse polishing solution;
and step S3: filtering the recovered rough polishing solution for the first time, and transmitting the recovered rough polishing solution to a second recovery barrel; and
and step S4: and filtering the recovered rough polishing solution for the second time, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process.
Optionally, step S1 includes:
providing initial rough polishing stock solution preparation, and supplying the initial rough polishing stock solution preparation to a final polishing machine;
providing a silicon substrate, and performing rough polishing of a final polishing process on the silicon substrate by using the initial rough polishing stock solution preparation solution on the final polishing machine table to obtain a rough polishing solution to be recovered; and
and the final polishing machine station discharges and collects the rough polishing liquid into a first recovery barrel.
Optionally, step S2 includes:
measuring a measured pH value of the crude polishing solution in the first recovery tank, and comparing the measured pH value with a set pH value;
and if the measured pH value is not in the set value range, adjusting the pH value of the rough polishing solution to bring the pH value of the rough polishing solution to the set range.
Further, the pH value of the rough polishing solution is set within a range of 10.2 to 10.8.
Optionally, step S2 includes:
and in the first recovery barrel, using an alkaline material to adjust the pH value of the rough polishing solution until the pH value of the rough polishing solution is adjusted to a set range.
Further, the alkaline material is potassium hydroxide.
Optionally, step S3 includes:
performing primary filtration treatment on the recycled coarse polishing solution with the pH value within a set range through a filter to filter out solid impurities in the recycled coarse polishing solution; and
and then the recovered coarse polishing solution is recovered to a second recovery barrel through a recovery pipeline.
Optionally, step S4 includes:
filtering the recovered coarse polishing solution in the second recovery barrel for the second time;
and injecting the recovered rough polishing solution into a stirring barrel for preparing rough polishing stock solution preparation required by the double-sided polishing process, and supplementing an additive required for controlling the pH value into the stirring barrel so as to adjust the pH value of the recovered rough polishing solution to a target range, thereby obtaining the rough polishing stock solution preparation required by the double-sided polishing process.
Further, the additive comprises a high molecular polymer and a metal chelating agent.
Further, after step S4, the method further includes:
and supplying the rough polishing stock solution to a double-sided polishing machine for use.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a method for recycling a rough polishing solution, which comprises the following steps: step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin; step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain a recovered coarse polishing solution; and step S3: filtering the recovered rough polishing solution for the first time, and transmitting the recovered rough polishing solution to a second recovery barrel; and step S4: and filtering the recovered rough polishing solution for the second time, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process, so that the rough polishing solution of the final polishing process is recovered and reused, the waste of the polishing solution is reduced, and the cost is saved.
Drawings
Fig. 1 is a schematic flow chart illustrating a method for recycling a rough polishing solution according to an embodiment of the present invention.
Detailed Description
The method of recycling a rough polishing liquid of the present invention will be described in further detail below. The present invention will now be described in more detail with reference to the accompanying drawings, in which preferred embodiments of the invention are shown, it being understood that one skilled in the art may modify the invention herein described while still achieving the advantageous effects of the invention. Accordingly, the following description should be construed as broadly as possible to those skilled in the art and not as limiting the invention.
In the interest of clarity, not all features of an actual implementation are described. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific details must be set forth in order to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art.
In order to make the objects and features of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. It is to be noted that the drawings are in a very simplified form and are all used in a non-precise ratio for the purpose of facilitating and distinctly aiding in the description of the embodiments of the invention.
Fig. 1 is a schematic flow chart of a method for recycling a rough polishing solution according to this embodiment. As shown in FIG. 1, the present embodiment provides a method for recycling a rough polishing solution. Wherein the rough polishing solution is subjected to the final polishing process.
The method for recycling the rough polishing solution comprises the following steps:
step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin;
step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain a recovered coarse polishing solution;
and step S3: filtering the recovered coarse polishing solution for the first time, and transmitting the recovered coarse polishing solution to a second recovery barrel;
and step S4: and filtering the recovered rough polishing solution for the second time, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process.
The method for recycling the rough polishing solution provided in this embodiment is described in detail below.
First, step S1 is performed to recycle the coarse polishing solution after the final polishing process into a first recycling tank.
The method specifically comprises the following steps:
firstly, providing initial rough polishing stock solution preparation, and supplying the initial rough polishing stock solution preparation to a final polishing machine.
And then, providing a silicon substrate, and performing rough polishing of a final polishing process on the silicon substrate by using the initial rough polishing stock solution preparation solution on the final polishing machine table to obtain a rough polishing solution to be recycled.
Then, the final polishing machine station discharges and collects the rough polishing liquid into a first recycling barrel.
Then, step S2 is performed to adjust the pH of the coarse polishing solution in the first recycling bin to a predetermined range, so as to obtain a recycled coarse polishing solution.
In detail, the measured pH of the rough polishing solution in the first recovery tank is measured, and the measured pH is compared with a set pH. Wherein the pH was set at 10.5.
And if the measured pH value is not in a set value range, adjusting the pH value of the rough polishing solution, wherein the set value range is 10.2-10.8. In this embodiment, since the measured pH is less than 10.2, in the first recycling tank, an alkaline material, such as KOH (potassium hydroxide), is used to adjust the pH of the coarse polishing solution until the pH of the coarse polishing solution is adjusted to meet the pH requirement, that is, the measured pH is adjusted to be within a set value range, so as to obtain the recycled coarse polishing solution.
And then, executing step S3, filtering the recovered coarse polishing solution for the first time, and transmitting the recovered coarse polishing solution to a second recovery barrel.
In detail, the recycled coarse polishing solution meeting the requirement of pH value is subjected to a first filtering treatment by a filter to filter out the solid in the recycled coarse polishing solution; and then the recovered rough polishing solution is converged into a centralized recovery pipeline and is recovered to a second recovery barrel through the recovery pipeline.
And S4, performing secondary filtration on the recovered rough polishing solution, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process.
The method specifically comprises the following steps:
firstly, the recovered coarse polishing solution in the second recovery barrel is filtered for the second time, so that solid impurities in the recovered coarse polishing solution are further filtered, and impurities in the recovered coarse polishing solution are further reduced.
And then, injecting the recovered rough polishing solution into a stirring barrel for preparing rough polishing stock solution preparation required by the double-sided polishing process, and supplementing an additive required for controlling the pH value into the stirring barrel so as to adjust the pH value of the recovered rough polishing solution to a target range, thereby obtaining the rough polishing stock solution preparation required by the double-sided polishing process. Wherein the additives are, for example, high molecular polymers and metal chelating agents.
And finally, supplying the rough polishing stock solution to a double-sided polishing machine for use.
In summary, the present invention provides a method for recycling a rough polishing solution for final polishing, comprising the steps of: step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin; step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain recovered coarse polishing solution; and step S3: filtering the recovered coarse polishing solution for the first time, and transmitting the recovered coarse polishing solution to a second recovery barrel; and step S4: and filtering the recovered coarse polishing solution for the second time, and adjusting the pH value of the recovered coarse polishing solution to a target range to obtain a coarse polishing stock solution preparation solution required by the preparation of the double-sided polishing process, so that the coarse polishing solution of the final polishing process is recovered and reused, the waste of the polishing solution is reduced, and the cost is saved.
In addition, unless otherwise specified or indicated, the description of the terms "first" and "second" in the specification is only used for distinguishing various components, elements, steps and the like in the specification, and is not used for representing logical relationships or sequential relationships among the various components, elements, steps and the like.
It is to be understood that while the present invention has been described in conjunction with the preferred embodiments thereof, it is not intended to limit the invention to those embodiments. It will be apparent to those skilled in the art that many changes and modifications can be made, or equivalents employed, to the presently disclosed embodiments without departing from the intended scope of the invention. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.
Claims (10)
1. A method for recycling a rough polishing solution is characterized by comprising the following steps:
step S1: recycling the coarse polishing solution subjected to the final polishing process into a first recycling bin;
step S2: adjusting the pH value of the coarse polishing solution in a first recovery barrel to a set range to obtain recovered coarse polishing solution;
and step S3: filtering the recovered rough polishing solution for the first time, and transmitting the recovered rough polishing solution to a second recovery barrel; and
and step S4: and filtering the recovered rough polishing solution for the second time, and adjusting the pH value of the recovered rough polishing solution to a target range to obtain a rough polishing stock solution preparation solution required by the double-sided polishing process.
2. The method of claim 1, wherein step S1 comprises:
providing initial rough polishing stock solution preparation, and supplying the initial rough polishing stock solution preparation to a final polishing machine;
providing a silicon substrate, and performing rough polishing of a final polishing process on the silicon substrate by using the initial rough polishing stock solution preparation solution on the final polishing machine table to obtain a rough polishing solution to be recovered; and
and the final polishing machine station discharges and collects the rough polishing solution into a first recovery barrel.
3. The method of claim 1, wherein step S2 comprises:
measuring a measured pH value of the coarse polishing solution in the first recovery tank, and comparing the measured pH value with a set pH value;
and if the measured pH value is not in the set value range, adjusting the pH value of the rough polishing solution to bring the pH value of the rough polishing solution to the set range.
4. The method of recycling a raw polishing liquid according to claim 3, wherein the pH of the raw polishing liquid is set within a range of 10.2 to 10.8.
5. The method of recycling a rough polishing liquid according to claim 1, wherein the step S2 comprises:
and in the first recovery barrel, using an alkaline material to adjust the pH value of the rough polishing solution until the pH value of the rough polishing solution is adjusted to a set range.
6. The method of reusing a crude polishing liquid according to claim 5, wherein said alkaline material is potassium hydroxide.
7. The method of recycling a rough polishing liquid according to claim 1, wherein the step S3 comprises:
performing primary filtration treatment on the recycled coarse polishing solution with the pH value within a set range through a filter to filter out solid impurities in the recycled coarse polishing solution; and
and then the recovered coarse polishing solution is recovered to a second recovery barrel through a recovery pipeline.
8. The method of recycling a rough polishing liquid according to claim 1, wherein the step S4 comprises:
filtering the recovered coarse polishing solution in the second recovery barrel for the second time;
and injecting the recovered rough polishing solution into a stirring barrel for preparing rough polishing stock solution preparation required by the double-sided polishing process, and supplementing an additive required for controlling the pH value into the stirring barrel so as to adjust the pH value of the recovered rough polishing solution to a target range, thereby obtaining the rough polishing stock solution preparation required by the double-sided polishing process.
9. The method of reusing a crude polishing solution according to claim 8, wherein said additive comprises a high molecular polymer and a metal chelating agent.
10. The method of reusing a rough polishing liquid according to claim 3, further comprising, after step S4:
and supplying the rough polishing stock solution to a double-sided polishing machine for use.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211346937.5A CN115505339A (en) | 2022-10-31 | 2022-10-31 | Recycling method of coarse polishing solution |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211346937.5A CN115505339A (en) | 2022-10-31 | 2022-10-31 | Recycling method of coarse polishing solution |
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| CN115505339A true CN115505339A (en) | 2022-12-23 |
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| CN202211346937.5A Pending CN115505339A (en) | 2022-10-31 | 2022-10-31 | Recycling method of coarse polishing solution |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07316846A (en) * | 1994-05-27 | 1995-12-05 | Asahi Chem Ind Co Ltd | Method for regenerating chemical and mechanical polishing solution |
| CN103264352A (en) * | 2013-04-26 | 2013-08-28 | 中国科学院上海光学精密机械研究所 | Polishing liquid circulating filtration and injection device for large-sized ring polishing machine |
| CN109623508A (en) * | 2019-01-25 | 2019-04-16 | 云南蓝晶科技有限公司 | LED sapphire wafer numerical control polishing method based on high mixture ratio polishing fluid |
| CN110509173A (en) * | 2019-09-04 | 2019-11-29 | 天津中环领先材料技术有限公司 | A kind of polishing fluid recyclable device and its control method |
| CN110746889A (en) * | 2019-09-03 | 2020-02-04 | 福建晶安光电有限公司 | Method for recycling polishing solution in semiconductor wafer processing process |
| CN215357898U (en) * | 2021-07-28 | 2021-12-31 | 昂士特科技(深圳)有限公司 | Coarse polishing equipment for recycled wafers |
| CN215470448U (en) * | 2021-08-11 | 2022-01-11 | 昂士特科技(深圳)有限公司 | Semiconductor chemical mechanical polishing liquid recovery processing device |
-
2022
- 2022-10-31 CN CN202211346937.5A patent/CN115505339A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07316846A (en) * | 1994-05-27 | 1995-12-05 | Asahi Chem Ind Co Ltd | Method for regenerating chemical and mechanical polishing solution |
| CN103264352A (en) * | 2013-04-26 | 2013-08-28 | 中国科学院上海光学精密机械研究所 | Polishing liquid circulating filtration and injection device for large-sized ring polishing machine |
| CN109623508A (en) * | 2019-01-25 | 2019-04-16 | 云南蓝晶科技有限公司 | LED sapphire wafer numerical control polishing method based on high mixture ratio polishing fluid |
| CN110746889A (en) * | 2019-09-03 | 2020-02-04 | 福建晶安光电有限公司 | Method for recycling polishing solution in semiconductor wafer processing process |
| CN110509173A (en) * | 2019-09-04 | 2019-11-29 | 天津中环领先材料技术有限公司 | A kind of polishing fluid recyclable device and its control method |
| CN215357898U (en) * | 2021-07-28 | 2021-12-31 | 昂士特科技(深圳)有限公司 | Coarse polishing equipment for recycled wafers |
| CN215470448U (en) * | 2021-08-11 | 2022-01-11 | 昂士特科技(深圳)有限公司 | Semiconductor chemical mechanical polishing liquid recovery processing device |
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Application publication date: 20221223 |