CN115124927A - Green chemical mechanical polishing solution for silicon carbide crystals - Google Patents
Green chemical mechanical polishing solution for silicon carbide crystals Download PDFInfo
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- CN115124927A CN115124927A CN202210838534.6A CN202210838534A CN115124927A CN 115124927 A CN115124927 A CN 115124927A CN 202210838534 A CN202210838534 A CN 202210838534A CN 115124927 A CN115124927 A CN 115124927A
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- silicon carbide
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- 238000005498 polishing Methods 0.000 title claims abstract description 50
- 239000013078 crystal Substances 0.000 title claims abstract description 33
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 title claims abstract description 33
- 229910010271 silicon carbide Inorganic materials 0.000 title claims abstract description 33
- 239000000126 substance Substances 0.000 title claims abstract description 15
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 34
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims abstract description 14
- 239000002270 dispersing agent Substances 0.000 claims abstract description 11
- 239000008367 deionised water Substances 0.000 claims abstract description 9
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims abstract description 7
- 235000017557 sodium bicarbonate Nutrition 0.000 claims abstract description 7
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 claims abstract description 4
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 claims description 9
- 239000002245 particle Substances 0.000 claims description 8
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 7
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 6
- VHSHLMUCYSAUQU-UHFFFAOYSA-N 2-hydroxypropyl methacrylate Chemical compound CC(O)COC(=O)C(C)=C VHSHLMUCYSAUQU-UHFFFAOYSA-N 0.000 claims description 3
- 239000002202 Polyethylene glycol Substances 0.000 claims description 3
- 229920001223 polyethylene glycol Polymers 0.000 claims description 3
- 239000006061 abrasive grain Substances 0.000 claims description 2
- 239000000463 material Substances 0.000 abstract description 13
- 230000003746 surface roughness Effects 0.000 abstract description 13
- 239000007788 liquid Substances 0.000 abstract description 9
- 239000002699 waste material Substances 0.000 abstract description 6
- 239000002253 acid Substances 0.000 abstract description 3
- 229910001385 heavy metal Inorganic materials 0.000 abstract description 3
- 238000009776 industrial production Methods 0.000 abstract description 3
- 150000002500 ions Chemical class 0.000 abstract description 3
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 abstract description 3
- 239000007795 chemical reaction product Substances 0.000 abstract description 2
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 abstract 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 8
- 229910052710 silicon Inorganic materials 0.000 description 8
- 239000010703 silicon Substances 0.000 description 8
- 239000004065 semiconductor Substances 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 238000005259 measurement Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 239000003642 reactive oxygen metabolite Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 description 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 229910052732 germanium Inorganic materials 0.000 description 1
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000004807 localization Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 230000009466 transformation Effects 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
- C09G1/02—Polishing compositions containing abrasives or grinding agents
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The green chemical mechanical polishing solution for the silicon carbide crystals is a green, efficient and high-quality chemical mechanical polishing solution for the silicon carbide crystals, comprises hydrogen peroxide, aluminum oxide, sodium bicarbonate, a dispersing agent and deionized water, and is used for chemically and mechanically polishing the silicon carbide crystals. Wherein the concentration of the hydrogen peroxide is 20 wt% -30 wt%, the concentration of the aluminum oxide is 3 wt% -8 wt%, the molar ratio of the hydrogen peroxide to the sodium bicarbonate is 5-20, the concentration of the dispersing agent is 0.5 wt% to 5 wt%, and the balance is deionized water. After the polishing solution is used for polishing the silicon carbide crystal, an ultra-smooth surface with the surface roughness of 0.081nm can be obtained with the material removal rate of 132 nm/h. In addition, the polishing solution is different from other traditional polishing solutions containing strong acid, strong base and heavy metal ions, contains various components and reaction products which have no pollution to the environment, can solve the problems of difficult treatment and high treatment cost of polishing waste liquid in the industrial production process, reduces the production cost, and is beneficial to large-scale industrial production.
Description
Technical Field
The invention belongs to the technical field of ultraprecise processing of superhard materials, and relates to a green high-quality silicon carbide crystal chemical mechanical polishing solution.
Background
The semiconductor industry is an important development field of the industry integration and transformation innovation of China, and common semiconductor materials comprise silicon, germanium, gallium arsenide and the like. Silicon carbide crystals, which are typical third-generation semiconductor materials, have the advantages of high thermal conductivity, high breakdown field strength, high electron drift rate, large forbidden band width and the like. Due to the characteristics of high efficiency, high temperature and high frequency, silicon carbide crystals are very important in fields with extremely strict requirements on temperature and efficiency. The method is widely applied to photovoltaic industry, new energy automobile motor controllers, PFC/power supplies and the like.
The service performance of the components is influenced by the processing quality and precision of the silicon carbide crystal. Therefore, a high quality of the processed surface is a necessary requirement for silicon carbide crystals as substrate materials. Chemical mechanical polishing is a technology for realizing the ultra-smooth processing of the crystal surface through the synergistic action of mechanical removal and chemical corrosion, and is the only method for realizing the global planarization of the silicon carbide crystal at present. The polishing liquid is a key factor determining the polishing quality. In addition, domestic polishing solutions often contain strong acid, strong base and heavy metal ions. The polishing waste liquid can cause serious pollution to the environment. The neutralization of strong acid and strong base in the polishing waste liquid and the removal of heavy metal ions increase the treatment cost of the waste liquid. Therefore, the development of the green, high-efficiency and high-quality chemical mechanical polishing solution for the silicon carbide crystals has important practical significance for breaking foreign monopoly and realizing the localization of the semiconductor industry.
Disclosure of Invention
In order to solve the problems of poor quality of a processed surface, low efficiency, environmental pollution and the like of a silicon carbide crystal in the traditional chemical mechanical polishing process, the invention provides the chemical mechanical polishing solution for the silicon carbide crystal, and the green, high-efficiency and high-quality chemical mechanical polishing of the silicon carbide crystal is realized.
In order to achieve the purpose, the invention adopts the technical scheme that:
the chemical mechanical polishing solution for the green and high-quality silicon carbide crystals comprises hydrogen peroxide, alumina abrasive particles, sodium bicarbonate, a dispersing agent and deionized water. Wherein: the concentration of the hydrogen peroxide is 20 to 30 weight percent; the grain diameter of the alumina abrasive grain is 0.03-1 μm, and the concentration is 3-8 wt%; the molar ratio of the hydrogen peroxide to the sodium bicarbonate is 5-20; the concentration of the dispersant is 0.5 to 3 weight per thousand. The weight percentage of the deionized water is 62-87%. The polishing solution is dripped to polish silicon carbide crystals.
Further, the dispersing agent is one or more of polyethylene glycol, glycerol, ethanol and HPMA.
And (3) mixing the components at room temperature, uniformly stirring, and oscillating in ultrasonic equipment for 10min to obtain the polishing solution.
The invention has the following effects and benefits:
1) the invention activates hydrogen peroxide through sodium bicarbonate, so that a large amount of ROS (reactive oxygen species) is generated in the polishing solution. ROS has strong oxidizability, and can oxidize the surface of the silicon carbide to form a soft oxide layer on the surface. And finally, removing the oxide layer under the action of the abrasive particles to form an ultra-smooth surface.
2) Compared with the traditional polishing solution, the surface roughness of the polished silicon carbide crystal is reduced, and the material removal rate is improved.
3) The pH of the polishing solution is neutral, and the reaction product of the hydrogen peroxide as the oxidant and the sodium bicarbonate as the active agent is mainly CO 2 、O 2 、H 2 O, no pollution to the environment and environmental protection.
4) The polishing waste liquid does not need special treatment, and the abrasive particles can be discharged after being filtered, so that the waste liquid treatment cost is reduced, and the economic requirement of industrial production is met.
Drawings
FIG. 1 is a graph showing the measurement of the surface roughness profile of a polished silicon carbide crystal silicon surface using a ZygoNewView 9000 white light interferometer of the present invention. The results show a surface roughness of 0.267nm and a material removal rate of 70 nm/h.
FIG. 2 is a graph showing the measurement of the surface roughness profile of a polished silicon carbide crystal silicon surface using a ZygoNewView 9000 white light interferometer of the present invention. The results show that the surface roughness is 0.225nm and the material removal rate is 89 nm/h.
FIG. 3 is a graph showing the measurement of the surface roughness profile of a polished silicon carbide crystal silicon surface using a ZygoNewView 9000 white light interferometer of the present invention. The results show a surface roughness of 0.081nm and a material removal rate of 132 nm/h.
Detailed Description
The invention is further illustrated by the following specific examples, which should not be construed as limiting the scope of the invention.
The polishing sample piece is a silicon surface of the silicon carbide crystal, and the size of the polishing sample piece is 1cm multiplied by 1 cm. The three silicon carbide crystal samples are uniformly adhered to the carrier plate. The used polishing machine is a UNIPOL-1200S automatic grinding polishing machine, the rotation speed of a polishing disc is set to be 70rpm, the polishing pressure is set to be 0.03MPa, the rotation speed of the polishing disc is 70r/min, the polishing pad is a polyurethane polishing pad with the phi of 300mm, the flow of polishing liquid is 10ml/min, and the polishing time is 60 min.
After polishing, the surface roughness was measured using a ZygoNewView 9000 white light interferometer. The scan range is 10 μm × 10 μm.
Example 1:
polishing solution: the concentration of hydrogen peroxide is 10 wt%, the concentration of alumina abrasive particles is 3 wt%, the particle size is 1 mu m, the molar ratio of hydrogen peroxide to sodium bicarbonate is 5, the weight percentage of deionized water is 87%, and the concentration of dispersing agent HPMA is 0.5 wt%. After mixing, stirring evenly and oscillating for 10min in an ultrasonic device.
The surface roughness of the silicon surface of the polished silicon carbide crystal is 0.267nm (see the attached figure 1), and the material removal rate is 70 nm/h.
Example 2:
polishing solution: the concentration of hydrogen peroxide is 20 wt%, the concentration of alumina is 5 wt%, the particle size is 0.5 μm, the molar ratio of hydrogen peroxide to sodium bicarbonate is 20, the weight percentage of deionized water is 75%, and the concentration of the dispersant glycerol is 2 wt%. After mixing, stirring evenly and oscillating for 10min in an ultrasonic device.
The surface roughness of the silicon surface of the polished silicon carbide crystal is 0.225nm (see the attached figure 2), and the material removal rate is 89 nm/h.
Example 3:
polishing solution: the concentration of hydrogen peroxide is 30 wt%, the concentration of aluminum oxide is 8 wt%, the particle size is 0.03nm, the molar ratio of hydrogen peroxide to sodium bicarbonate is 10, the weight percentage of deionized water is 62%, and the concentration of dispersant polyethylene glycol is 5 wt%. After mixing, stirring evenly and oscillating for 10min in an ultrasonic device.
The surface roughness of the silicon surface of the polished silicon carbide crystal is 0.081nm (shown in figure 3), and the material removal rate is 132 nm/h. Namely, after the polishing liquid is used for polishing the silicon carbide crystal, an ultra-smooth surface with the surface roughness of 0.081nm can be obtained with the material removal rate of 132 nm/h.
The above-mentioned embodiments only represent the embodiments of the present invention, but they should not be understood as the limitation of the scope of the present invention, and it should be noted that those skilled in the art can make several variations and modifications without departing from the spirit of the present invention, and these all fall into the protection scope of the present invention.
Claims (3)
1. The green and high-quality chemical mechanical polishing solution for the silicon carbide crystals can be used for polishing the silicon carbide crystals by dripping the polishing solution, and is characterized in that the components of the polishing solution comprise hydrogen peroxide, alumina abrasive particles, sodium bicarbonate, a dispersing agent and deionized water;
the concentration of the hydrogen peroxide is 20 to 30 weight percent; the concentration of the alumina is 3 to 8 weight percent; the molar ratio of the hydrogen peroxide to the sodium bicarbonate is 5-20; the concentration of the dispersant is 0.5 to 3 weight per thousand; the balance being deionized water.
2. The chemical mechanical polishing solution for green and high quality silicon carbide crystals according to claim 1, wherein the alumina abrasive grains have a grain size of 0.03 to 1 μm.
3. The chemical mechanical polishing solution for green and high-quality silicon carbide crystals according to claim 1, wherein the dispersant is one or more of polyethylene glycol, glycerol, ethanol and HPMA.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210838534.6A CN115124927A (en) | 2022-07-18 | 2022-07-18 | Green chemical mechanical polishing solution for silicon carbide crystals |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210838534.6A CN115124927A (en) | 2022-07-18 | 2022-07-18 | Green chemical mechanical polishing solution for silicon carbide crystals |
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| CN115124927A true CN115124927A (en) | 2022-09-30 |
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| CN202210838534.6A Pending CN115124927A (en) | 2022-07-18 | 2022-07-18 | Green chemical mechanical polishing solution for silicon carbide crystals |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010040280A1 (en) * | 2008-10-10 | 2010-04-15 | 安集微电子（上海）有限公司 | Chemical-mechanical polishing liquid |
| CN102533124A (en) * | 2010-12-31 | 2012-07-04 | 上海硅酸盐研究所中试基地 | Polishing solution for silicon carbide substrate |
| CN104835731A (en) * | 2015-05-05 | 2015-08-12 | 山东天岳晶体材料有限公司 | Quick polishing method for large-dimension 4H,6H-SiC wafer |
| CN105773399A (en) * | 2016-03-29 | 2016-07-20 | 清华大学 | Polishing solution, polishing machine and polishing method |
| CN107880784A (en) * | 2017-12-04 | 2018-04-06 | 苏州市宽道模具机械有限公司 | A kind of high-performance polishing fluid and preparation method thereof |
| CN109554119A (en) * | 2018-11-02 | 2019-04-02 | 山东天岳先进材料科技有限公司 | A kind of stability-enhanced silicon carbide chemical mechanical polishing liquid of pH and its application |
| CN111073520A (en) * | 2019-12-25 | 2020-04-28 | 苏州纳迪微电子有限公司 | Polishing powder for polishing silicon carbide wafer, preparation method thereof and polishing solution |
| WO2021135805A1 (en) * | 2019-12-31 | 2021-07-08 | 安集微电子（上海）有限公司 | Chemical-mechanical polishing liquid and use thereof in copper polishing |
| CN114654380A (en) * | 2022-04-07 | 2022-06-24 | 大连理工大学 | Electrochemical mechanical polishing method for silicon carbide wafer |
-
2022
- 2022-07-18 CN CN202210838534.6A patent/CN115124927A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010040280A1 (en) * | 2008-10-10 | 2010-04-15 | 安集微电子（上海）有限公司 | Chemical-mechanical polishing liquid |
| CN102533124A (en) * | 2010-12-31 | 2012-07-04 | 上海硅酸盐研究所中试基地 | Polishing solution for silicon carbide substrate |
| CN104835731A (en) * | 2015-05-05 | 2015-08-12 | 山东天岳晶体材料有限公司 | Quick polishing method for large-dimension 4H,6H-SiC wafer |
| CN105773399A (en) * | 2016-03-29 | 2016-07-20 | 清华大学 | Polishing solution, polishing machine and polishing method |
| CN107880784A (en) * | 2017-12-04 | 2018-04-06 | 苏州市宽道模具机械有限公司 | A kind of high-performance polishing fluid and preparation method thereof |
| CN109554119A (en) * | 2018-11-02 | 2019-04-02 | 山东天岳先进材料科技有限公司 | A kind of stability-enhanced silicon carbide chemical mechanical polishing liquid of pH and its application |
| CN111073520A (en) * | 2019-12-25 | 2020-04-28 | 苏州纳迪微电子有限公司 | Polishing powder for polishing silicon carbide wafer, preparation method thereof and polishing solution |
| WO2021135805A1 (en) * | 2019-12-31 | 2021-07-08 | 安集微电子（上海）有限公司 | Chemical-mechanical polishing liquid and use thereof in copper polishing |
| CN114654380A (en) * | 2022-04-07 | 2022-06-24 | 大连理工大学 | Electrochemical mechanical polishing method for silicon carbide wafer |
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