CN115924922A - Silica sol for chemical mechanical polishing and preparation method and application thereof - Google Patents
Silica sol for chemical mechanical polishing and preparation method and application thereof Download PDFInfo
- Publication number
- CN115924922A CN115924922A CN202310106131.7A CN202310106131A CN115924922A CN 115924922 A CN115924922 A CN 115924922A CN 202310106131 A CN202310106131 A CN 202310106131A CN 115924922 A CN115924922 A CN 115924922A
- Authority
- CN
- China
- Prior art keywords
- silica sol
- chemical mechanical
- mechanical polishing
- polishing
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 114
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 title claims abstract description 79
- 239000000126 substance Substances 0.000 title claims abstract description 61
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 44
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 claims abstract description 36
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 31
- 239000002245 particle Substances 0.000 claims abstract description 29
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 21
- 238000006243 chemical reaction Methods 0.000 claims abstract description 18
- 239000011259 mixed solution Substances 0.000 claims abstract description 18
- 239000000243 solution Substances 0.000 claims abstract description 17
- 239000000463 material Substances 0.000 claims abstract description 14
- 235000012239 silicon dioxide Nutrition 0.000 claims abstract description 14
- 238000003756 stirring Methods 0.000 claims abstract description 14
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 13
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 13
- 239000010703 silicon Substances 0.000 claims abstract description 13
- 239000003054 catalyst Substances 0.000 claims abstract description 9
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 19
- 239000004065 semiconductor Substances 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- ZRBROGSAUIUIJE-UHFFFAOYSA-N azanium;azane;chloride Chemical compound N.[NH4+].[Cl-] ZRBROGSAUIUIJE-UHFFFAOYSA-N 0.000 claims description 4
- QKNYBSVHEMOAJP-UHFFFAOYSA-N 2-amino-2-(hydroxymethyl)propane-1,3-diol;hydron;chloride Chemical group Cl.OCC(N)(CO)CO QKNYBSVHEMOAJP-UHFFFAOYSA-N 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000002904 solvent Substances 0.000 abstract description 5
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 abstract description 4
- 230000001276 controlling effect Effects 0.000 abstract description 4
- 230000009471 action Effects 0.000 abstract description 3
- 230000001105 regulatory effect Effects 0.000 abstract description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 22
- 235000012431 wafers Nutrition 0.000 description 14
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonium chloride Substances [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 13
- 229910021529 ammonia Inorganic materials 0.000 description 11
- 239000007853 buffer solution Substances 0.000 description 11
- 239000008367 deionised water Substances 0.000 description 10
- 229910021641 deionized water Inorganic materials 0.000 description 10
- 238000012360 testing method Methods 0.000 description 9
- 239000010408 film Substances 0.000 description 8
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 6
- 238000003917 TEM image Methods 0.000 description 6
- 235000011114 ammonium hydroxide Nutrition 0.000 description 6
- 239000003921 oil Substances 0.000 description 6
- 239000007788 liquid Substances 0.000 description 5
- 239000002105 nanoparticle Substances 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 238000000227 grinding Methods 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 4
- 239000007800 oxidant agent Substances 0.000 description 4
- 230000003746 surface roughness Effects 0.000 description 4
- 244000282866 Euchlaena mexicana Species 0.000 description 3
- 235000019270 ammonium chloride Nutrition 0.000 description 3
- 229910000420 cerium oxide Inorganic materials 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000006460 hydrolysis reaction Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 description 3
- 239000004094 surface-active agent Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- 239000003082 abrasive agent Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010790 dilution Methods 0.000 description 2
- 239000012895 dilution Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 230000007062 hydrolysis Effects 0.000 description 2
- 239000010985 leather Substances 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 238000007517 polishing process Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 244000284380 Hibiscus rosa sinensis Species 0.000 description 1
- 235000000100 Hibiscus rosa sinensis Nutrition 0.000 description 1
- 235000016785 Rosa della China Nutrition 0.000 description 1
- 239000012736 aqueous medium Substances 0.000 description 1
- 238000000089 atomic force micrograph Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000006184 cosolvent Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 235000002741 hibiscus rosa-sinensis Nutrition 0.000 description 1
- 229960002163 hydrogen peroxide Drugs 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000005304 optical glass Substances 0.000 description 1
- -1 pH regulator Substances 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 description 1
- 229910010271 silicon carbide Inorganic materials 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Mechanical Treatment Of Semiconductor (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention provides silica sol for chemical mechanical polishing and a preparation method and application thereof. The preparation method comprises the following steps: adding an alkaline catalyst into water to obtain a mixed solution, heating the mixed solution to a reaction temperature, adding tetraethoxysilane, and reacting under a stirring condition; after the reaction is finished, the silica sol for chemical mechanical polishing is obtained. In the invention, tetraethoxysilane is used as a silicon source, water is used as a solvent, TEOS is slowly hydrolyzed at an oil-water interface under the action of an alkaline catalyst, a silicate substance is continuously provided for a water phase, and the silicate substance is immediately consumed for the growth of mother particles without forming new particles. By controlling the pH value of the water phase, the reaction temperature, the stirring speed of the reaction solution and the quality of TEOS, the particle size of silicon dioxide can be effectively regulated and controlled to be 10-100 nm, so that silica sol with uniform particle size and good dispersibility is obtained, and the silica sol can be used for fine polishing of CMP (chemical mechanical polishing), so that the material removal rate can be remarkably increased, and the surface quality of a workpiece is improved.
Description
Technical Field
The invention relates to silica sol for chemical mechanical polishing and a preparation method and application thereof, belonging to the technical field of nano materials.
Background
Chemical Mechanical Polishing (CMP) is one of the most advanced planarization techniques at present, and is an essential polishing process in semiconductor manufacturing. The basic principle of the CMP process is that a polishing workpiece rotates relative to a polishing pad under certain pressure and the existence of polishing liquid, in the process, an oxidizing agent in the polishing liquid existing between the surface of the workpiece and the polishing pad chemically reacts with the surface material of the workpiece to generate a layer of chemical reaction film on the surface of the workpiece, then the layer of chemical reaction film is removed by abrasive in the polishing liquid and the polishing pad through mechanical grinding, so that the surface of the workpiece is exposed again, and finally, effective removal and good surface quality are realized in the alternate process of chemical reaction and mechanical grinding.
Under the well-defined conditions of the polishing machine and the workpiece to be polished, the polishing liquid and the polishing conditions become major factors that greatly affect the polishing result, wherein the polishing liquid is a decisive factor that affects the CMP performance. The polishing solution consists of abrasive, soluble chemical substances (oxidant, pH regulator, dispersant and the like) and an aqueous medium, wherein the abrasive is the main component of the polishing solution and directly influences the surface quality and the material removal rate, so that the hardness, the particle size, the morphology and the uniformity of the abrasive have great influence on the quality of a workpiece after CMP.
The common abrasive in the chemical mechanical polishing solution is silicon dioxide, aluminum oxide and cerium oxide, the aluminum oxide has higher hardness, is easy to agglomerate and has poor dispersibility, and the common abrasive is usually used for materials with higher hardness, such as silicon carbide; the cerium oxide has moderate hardness, and because cerium has multiple valence states and different valence states are easy to convert, substances on the surface of the glass are easy to oxidize or complex, the cerium oxide is widely applied to chemical mechanical polishing of mobile phone screens, optical glass and the like. Silica sol is a dispersion of nano-sized silica particles in water or a solvent, and since silica sol has good dispersibility and stability, polishing solutions composed of silica sol have been widely used in semiconductor polishing.
Researches find that the spherical silicon dioxide polishing solution with small particle size and uniform distribution can reduce polishing scratches and better meet the requirement of CMP abrasive on the surface of a high-quality wafer. The production method of the silica sol commonly used in industry is an ion exchange method, however, the preparation process of the method is complex, the reaction time is long, the uniformity of the synthesized silicon dioxide is poor, and the requirement of CMP fine polishing cannot be met. In addition, a surfactant is required to be added as a template and an additive in the preparation of the existing silica sol, otherwise, the uniformity and the stability of the obtained silica sol are poor, but the environmental protection property of the silica sol is poor due to the use of the surfactant.
Therefore, there is a need for an improved CMP abrasive material by a simple preparation process, a short reaction time, and a silica sol having uniform particle size distribution, small and uniform particle size, which is environmentally friendly. The invention is therefore set forth.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides silica sol for chemical mechanical polishing and a preparation method and application thereof. The invention is compared with the prior art
The method is improved, tetraethoxysilane (TEOS) is used as a silicon source, water is used as a solvent, the TEOS is slowly hydrolyzed at an oil-water interface under the action of an alkaline catalyst, a silicate substance is continuously provided for a water phase, and the silicate substance is immediately consumed for the growth of mother particles without forming new particles. By controlling the pH value of a water phase, the reaction temperature, the stirring speed of a reaction solution and the quality of TEOS, the particle size of silicon dioxide can be effectively regulated and controlled to be between 10 and 100nm, so that the silica sol with uniform particle size and good dispersibility is obtained, and the silica sol can be used for the fine polishing of CMP (chemical mechanical polishing), so that the material removal rate can be remarkably improved, and the surface quality of a workpiece can be improved.
In order to achieve the technical purpose, the invention is specifically realized by the following technical scheme:
a preparation method of silica sol for chemical mechanical polishing comprises the following steps:
adding an alkaline catalyst into water to obtain a mixed solution, heating the obtained mixed solution to a reaction temperature, adding Tetraethoxysilane (TEOS), and reacting under a stirring condition; after the reaction is finished, the silica sol for chemical mechanical polishing is obtained.
According to the invention, the basic catalyst is a Tris-HCl buffer solution or an ammonia-ammonium chloride buffer solution; further preferably an ammonia-ammonium chloride buffer solution; the pH value of the Tris-HCl buffer solution is 8-9, the pH value of the ammonia water-ammonium chloride buffer solution is 10-11, and the mass fraction of ammonia in the ammonia water is 25-28 wt%.
According to the present invention, the pH of the mixed solution is preferably 8 to 11, and more preferably 9 to 10.5.
According to the present invention, the reaction temperature is preferably 25 to 100 ℃, more preferably 40 to 80 ℃.
According to the invention, the mass ratio of the Tetraethoxysilane (TEOS) to the water is preferably 0.1-1; the Tetraethoxysilane (TEOS) is equally divided into 2 to 6 batches to be added into the system, and each batch of tetraethoxysilane is added and then stirred to react for 2 to 8 hours.
Preferably, according to the invention, the stirring speed is between 200 and 2000rpm.
According to the invention, the silica sol for chemical mechanical polishing preferably has a silica content of 1 to 15wt%, a pH value of 8 to 10, and uniform spherical silica particles having a particle size of 10 to 100nm.
The invention also provides silica sol for chemical mechanical polishing, which is prepared by the preparation method.
According to the invention, the application of the silica sol for chemical mechanical polishing in the chemical mechanical polishing solution is provided; preferably, the silica sol for chemical mechanical polishing is used as an abrasive material in a chemical polishing solution for semiconductor materials and devices.
Compared with the prior art, the invention has the following beneficial effects:
1. the silica sol for chemical mechanical polishing disclosed by the invention takes Tetraethoxysilane (TEOS) as a silicon source and water as a solvent, under the action of a specific alkaline catalyst, the pH of a water phase is adjusted, so that the rapid reduction of the pH caused by TEOS hydrolysis can be overcome, the TEOS hydrolysis is promoted and then is subjected to polycondensation to form uniform nano particles, the gradient particle size of the silica can be effectively regulated to 10-100 nm by controlling the reaction temperature, the stirring speed and the quality of the silicon source, and finally, the synthesized silica has uniform particle size, good dispersibility and good stability and can be stored for a long time without sedimentation. Meanwhile, the surface area of the silicon dioxide particles is large, so that the contact area between the workpiece and the abrasive in the polishing solution can be increased, the material removal rate is effectively improved, scratches and scratches in the polishing process are reduced, and the roughness of the surface of the polished workpiece is reduced.
2. Preparation of the silica sols according to the invention, and
compared with the method, the method does not use a cosolvent, the TEOS and water form a two-phase interface after contacting, the oil phase and the water phase are contacted with each other by stirring, the TEOS hydrolysis reaction is carried out on the oil-water interface, the preparation process is simple and easy to repeat, the silicon dioxide with the particle size of 10-100 nm can be synthesized by controlling the reaction conditions, and the technical problem that the silicon dioxide with different gradient particle sizes can be prepared by a multi-step method in the prior art is solved.
3. Compared with the reported literature and patents, the preparation method of the silica sol only uses water as a solvent in a reaction system, does not need to use a surfactant as a template and an additive, and has the advantages of environmental friendliness, no pollution and good stability.
Drawings
FIG. 1 is a TEM image of a silica sol for chemical mechanical polishing prepared in example 1.
FIG. 2 is a TEM image of the silica sol for chemical mechanical polishing prepared in example 2.
FIG. 3 is a graph showing the particle size distribution of the initial silica sol prepared in example 2 and the silica sol before and after six months of standing.
FIG. 4 is a TEM image of the silica sol for chemical mechanical polishing obtained in example 3.
FIG. 5 is a graph showing the relationship between the change in film thickness after polishing of a silica thin film by using silica sol for chemical mechanical polishing and PL-3 silica sol obtained in examples 2 and 3, and time.
FIG. 6 is an AFM image of the silicon sol used for chemical mechanical polishing in example 3 after abrasive polishing.
Detailed Description
The present invention will be further described with reference to the following examples, but is not limited thereto.
Meanwhile, the experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
The PL-3 sol adopted in the experiment is purchased by Hibiscus rosa-sinensis refining processing company Limited; the rough polishing solution is VK-SP30W purchased from Hangzhou Zhi Ti purification technology Co.
Ammonia (NH) in the Ammonia Water used in the examples 3 ) The mass fraction of ammonia in (A) is 25-28 wt%.
Example 1
A preparation method of silica sol for chemical mechanical polishing comprises the following steps:
dissolving 1.08g of ammonium chloride in 4g of deionized water, adding 6mL of ammonia water after complete dissolution, adding deionized water for dilution to 20mL, and performing ultrasonic mixing to obtain an ammonia water-ammonium chloride buffer solution with the pH value of 10.5. 1mL of ammonia water-ammonium chloride buffer solution is added into 82.67g of deionized water, and the mixture is fully stirred and uniformly mixed to obtain a mixed solution with the pH value of 10.3. Heating the mixed solution to 50 ℃ under the oil bath condition, adjusting the rotating speed to 640rpm, adding 17.33g of TEOS, and reacting for 6 hours to ensure that the system becomes clear and transparent; continuously keeping the temperature and the stirring speed unchanged, adding 17.33g of TEOS into the system, reacting for 6h, then adding 17.33g of TEOS, reacting for 6h, finally adding 17.33g of TEOS, reacting for 6h to obtain light blue transparent spherical silica sol, namely the silica sol for chemical mechanical polishing, wherein SiO is 2 The solid content is 13.1wt%, and the pH value is between 8 and 9.
The TEM image of the silica sol for chemical mechanical polishing prepared in this example is shown in FIG. 1, and it can be seen from FIG. 1 that SiO in the silica sol is 2 The particle size of the nano-particles is about 20nm, the spherical shape is regular, the particle size is uniform, and the dispersity is good.
Example 2
A preparation method of silica sol for chemical mechanical polishing comprises the following steps:
1.08g of ammonium chloride was dissolved in 4g of deionized water, and 6mL of ammonia was added after completion of the dissolutionAdding deionized water to dilute to 20mL, and ultrasonically mixing uniformly to obtain the ammonia water-ammonium chloride buffer solution with the pH value of 10.5. 1mL of ammonia water-ammonium chloride buffer solution is added into 82.67g of deionized water, and the mixture is fully stirred and uniformly mixed to obtain a mixed solution with the pH value of 10.3. Heating the mixed solution to 80 ℃ under the oil bath condition, adjusting the rotating speed to 640rpm, adding 17.33g TEOS, and reacting for 4 hours to ensure that the system becomes clear and transparent; continuously keeping the temperature and the stirring speed unchanged, adding 17.33g of TEOS into the system, reacting for 4 hours, then adding 17.33g of TEOS, reacting for 4 hours, finally adding 17.33g of TEOS, reacting for 4 hours to obtain light blue transparent spherical silica sol, namely the silica sol for chemical mechanical polishing, wherein SiO is 2 The solid content is 13.1wt%, and the pH value is between 8 and 9.
The TEM image of the silica sol for chemical mechanical polishing prepared in this example is shown in FIG. 2, and it can be seen from FIG. 2 that SiO in the silica sol is 2 The particle size of the nano-particles is about 30nm, the spherical shape is regular, the particle size is uniform, and the dispersibility is good.
The stability of the silica sol prepared in this example was analyzed, and the particle size distribution curve of the silica sol after six months of standing is shown in fig. 3, and it can be seen from fig. 3 that the particle size of the obtained silica sol after six months of standing was substantially unchanged, which indicates that the silica sol prepared in this example has good stability.
Example 3
A preparation method of silica sol for chemical mechanical polishing comprises the following steps:
dissolving 1.08g of ammonium chloride in 4g of deionized water, adding 6mL of ammonia water after complete dissolution, adding deionized water for dilution to 20mL, and performing ultrasonic mixing to obtain an ammonia water-ammonium chloride buffer solution with the pH value of 10.5. 1mL of ammonia water-ammonium chloride buffer solution is added into 82.67g of deionized water, and the mixture is fully stirred and uniformly mixed to obtain a mixed solution with the pH value of 10.3. Heating the mixed solution to 80 ℃ under the oil bath condition, adjusting the rotating speed to 320rpm, adding 17.33g of TEOS, and reacting for 6 hours to ensure that the system becomes clear and transparent; continuously keeping the temperature and the stirring speed unchanged, adding 17.33g of TEOS into the system, reacting for 6h, then adding 17.33g of TEOS, reacting for 6h, finally adding 17.33g of TEOS, reacting for 6h, and obtaining light blue transparent spherical silica sol, namely the silica sol for chemical mechanical polishing, which is used for chemical mechanical polishingSiO 2 2 The solid content is 13.1wt%, and the pH value is between 8 and 9.
The TEM image of the silica sol for chemical mechanical polishing prepared in this example is shown in FIG. 4, and it can be seen from FIG. 4 that SiO in the obtained silica sol 2 The particle size of the nano-particles is about 40nm, the spherical shape is regular, the particle size is uniform, and the dispersibility is good.
Comparative example 1
A silica sol for chemical mechanical polishing was prepared as described in example 2, except that: ammonia water is used as an alkaline catalyst, and the method comprises the following specific steps: adding ammonia water into 82.67g of deionized water, and fully and uniformly stirring to obtain a mixed solution with the pH value of 10.3. Heating the mixed solution to 80 ℃ under the oil bath condition, adjusting the rotating speed to 640rpm, adding 17.33g of TEOS, reacting for 2 hours, wherein partial oil phase TEOS on the upper layer is unreacted, the pH value of the system is reduced rapidly and is about 8, and silica sol cannot be obtained.
Experimental example 1 chemical mechanical polishing Effect of silicon dioxide on silicon dioxide thin film on Single Crystal silicon wafer
1. Test materials: silica sol obtained in examples 2 and 3 and PL-3 silica sol.
2. The test method comprises the following steps: taking the silica sol and PL-3 silica sol of the embodiments 2 and 3 of the invention, adding water to dilute the PL-3 silica sol to have the same solid content of 13.1wt% as the embodiments 2 and 3, stirring and mixing uniformly, and then carrying out a chemical mechanical polishing test: cutting a 4-inch diameter single crystal silicon wafer deposited with a 300nm silicon dioxide film into 1X 1cm pieces 2 The 8 samples are taken to be uniformly pasted around the circumference of the carrying disc, a UNIPOL-1200S type automatic grinding polisher is used for polishing test, and the process parameters are as follows: the flow rate of the polishing solution is 350mL/h, the polishing pressure is 36.75kPa, the rotation speed is 20rpm, the polishing time is 1, 2, 3, 4 or 5min, and the polishing pad is the buffed leather polishing pad matched with the polishing machine.
The detection method of the polishing rate comprises the following steps: the polishing rate was measured by a film thickness meter, and the average thickness difference before and after polishing of 8 silicon wafers was measured to prepare a curve relating film thickness change to time.
3. And (3) test results: the relationship between the thickness change of the silica film after polishing and the time of the silica sol prepared in examples 2 and 3 and the PL-3 silica sol is shown in FIG. 5. It can be seen from FIG. 5 that the polishing effect of the silica sol prepared in examples 2 and 3 of the present invention applied to the polishing of the silica film is better than that of the commercially available PL-3 silica sol.
Experimental example 2 chemical mechanical polishing Effect of silicon dioxide on Single Crystal silicon wafer
1. Test materials: silica sol obtained in example 3.
2. The test method comprises the following steps:
(1) Preparing a fine polishing solution: 83.3 parts of silica sol prepared in the embodiment 3 of the invention and 16.6 parts of oxydol serving as an oxidant are taken, mixed and stirred uniformly, and then a polishing test is carried out.
(2) Chemical mechanical polishing test: cutting a 4-inch diameter single crystal silicon wafer into 1 × 1cm pieces 2 The small sample is prepared by uniformly sticking 8 samples around the circumference of a carrying disc, and performing polishing test by using a UNIPOL-1200S type automatic grinding and polishing machine, wherein the process parameters are as follows:
rough polishing: the VK-SP30W polishing solution has the flow rate of 350mL/h, the polishing pressure of 36.75kPa, the rotation speed of 80rpm and the polishing time of 0.5h, and the polishing pad is a polyurethane polishing pad matched with the polishing machine.
Fine polishing: the flow rate of the mixed solution of the silica sol and the hydrogen peroxide solution serving as the oxidant prepared in the example 3 is 700mL/h, the polishing pressure is 36.75kPa, the rotation speed is 80rpm, the polishing time is 1.5h, and the polishing pad is a buffed leather polishing pad matched with the polishing machine.
And after the rough polishing and the fine polishing, ultrasonically cleaning the polished wafer by using ethanol for 20 to 30min, and then drying the wafer by using nitrogen.
(3) The detection method of polishing rate and surface roughness comprises the following steps:
measuring the weight difference of 8 silicon wafers before and after polishing by adopting a gravimetric method, dividing the weight difference by the density and then by the area to obtain the thickness calculation thickness difference, and then dividing by the time to obtain the material removal rate; and measuring the surface roughness of the silicon wafer by adopting an atomic force microscope.
3. And (3) test results: the material removal rate of the silicon wafer after polishing is measured to be 8.19um/h, the surface roughness is 0.076nm, and the surface of the silicon wafer is smooth and has no residue and no scratch. Fig. 6 is an AFM scanning result of a polished silicon wafer, and it can be seen from the AFM scanning graph that the silica sol prepared in embodiment 3 of the present invention, when applied to a chemical mechanical polishing solution, effectively improves a material removal rate, and the surface roughness of the obtained silicon wafer can be lower than 0.1nm, which indicates that the silica sol prepared in the present invention can be applied to the field of ultra-precision processing of semiconductors.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which may be made by those skilled in the art without departing from the spirit and scope of the present invention as defined in the appended claims.
Claims (10)
1. A preparation method of silica sol for chemical mechanical polishing comprises the following steps:
adding an alkaline catalyst into water to obtain a mixed solution, heating the mixed solution to a reaction temperature, adding tetraethoxysilane, and reacting under a stirring condition; after the reaction is finished, the silica sol for chemical mechanical polishing is obtained.
2. The method for preparing the silica sol for chemical mechanical polishing according to claim 1, wherein the basic catalyst is Tris-HCl buffer or ammonia-ammonium chloride buffer; preferably an ammonia-ammonium chloride buffer.
3. The method of preparing the silica sol for chemical mechanical polishing according to claim 1, wherein the pH of the mixed solution is 8 to 11.
4. The method of preparing the silica sol for chemical mechanical polishing according to claim 1, wherein the pH of the mixed solution is 9 to 10.5.
5. The method for preparing the silica sol for chemical mechanical polishing according to claim 1, wherein the reaction temperature is 25 to 100 ℃, preferably 40 to 80 ℃.
6. The method for producing the silica sol for chemical mechanical polishing according to claim 1, wherein the mass ratio of the ethyl orthosilicate to the water is from 0.1 to 1; the tetraethoxysilane is added into the system in 2-6 batches, and each batch of tetraethoxysilane is stirred and reacts for 2-8 hours after being added.
7. The method for preparing the silica sol for chemical mechanical polishing according to claim 1, wherein the stirring speed is 200 to 2000rpm.
8. A silica sol for chemical mechanical polishing, which is prepared by the preparation method according to claim 1; the solid content of the silicon dioxide in the silicon sol for chemical mechanical polishing is 1-15 wt%, the pH value is 8-10, the silicon dioxide particles are uniform spherical, and the particle size is 10-100 nm.
9. The silica sol for chemical mechanical polishing according to claim 1, which is used in a chemical mechanical polishing solution.
10. The use according to claim 8, wherein the silica sol for chemical mechanical polishing is used as an abrasive in chemical polishing solutions for semiconductor materials and devices.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310106131.7A CN115924922A (en) | 2023-02-13 | 2023-02-13 | Silica sol for chemical mechanical polishing and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310106131.7A CN115924922A (en) | 2023-02-13 | 2023-02-13 | Silica sol for chemical mechanical polishing and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115924922A true CN115924922A (en) | 2023-04-07 |
Family
ID=86700861
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310106131.7A Pending CN115924922A (en) | 2023-02-13 | 2023-02-13 | Silica sol for chemical mechanical polishing and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115924922A (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005060219A (en) * | 2003-07-25 | 2005-03-10 | Fuso Chemical Co Ltd | Silica sol and manufacturing method therefor |
| WO2009070967A1 (en) * | 2007-11-30 | 2009-06-11 | Anji Microelectronics (Shanghai) Co., Ltd | A chemical-mechanical polishing liquid |
| CN102390838A (en) * | 2011-08-22 | 2012-03-28 | 天津晶岭电子材料科技有限公司 | Preparation method of non-spherical silica sol |
| CN103484024A (en) * | 2013-09-13 | 2014-01-01 | 上海新安纳电子科技有限公司 | Chemico-mechanical polishing liquid for silicon dioxide dielectric materials and preparing method thereof |
| CN109796935A (en) * | 2019-03-22 | 2019-05-24 | 大连理工大学 | A kind of preparation method of composite construction silica nanometer abrasive grain |
| CN112010318A (en) * | 2020-08-10 | 2020-12-01 | 深圳市科玺化工有限公司 | Preparation method of nano water-based silica sol for semiconductor polishing |
| CN113277522A (en) * | 2021-06-17 | 2021-08-20 | 航天特种材料及工艺技术研究所 | Light silica aerogel with ultrahigh transparency and ultralow haze, and preparation method and application thereof |
| CN113896204A (en) * | 2021-11-29 | 2022-01-07 | 苏州西丽卡电子材料有限公司 | Preparation method of ultra-high purity silica sol |
| CN114560468A (en) * | 2022-02-25 | 2022-05-31 | 金三江(肇庆)硅材料股份有限公司 | Silicon dioxide for chemical mechanical polishing and preparation method and application thereof |
| CN115353806A (en) * | 2022-08-01 | 2022-11-18 | 常州大学 | Silica sol with ultralow dispersion coefficient and preparation method and application thereof |
-
2023
- 2023-02-13 CN CN202310106131.7A patent/CN115924922A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005060219A (en) * | 2003-07-25 | 2005-03-10 | Fuso Chemical Co Ltd | Silica sol and manufacturing method therefor |
| WO2009070967A1 (en) * | 2007-11-30 | 2009-06-11 | Anji Microelectronics (Shanghai) Co., Ltd | A chemical-mechanical polishing liquid |
| CN102390838A (en) * | 2011-08-22 | 2012-03-28 | 天津晶岭电子材料科技有限公司 | Preparation method of non-spherical silica sol |
| CN103484024A (en) * | 2013-09-13 | 2014-01-01 | 上海新安纳电子科技有限公司 | Chemico-mechanical polishing liquid for silicon dioxide dielectric materials and preparing method thereof |
| CN109796935A (en) * | 2019-03-22 | 2019-05-24 | 大连理工大学 | A kind of preparation method of composite construction silica nanometer abrasive grain |
| CN112010318A (en) * | 2020-08-10 | 2020-12-01 | 深圳市科玺化工有限公司 | Preparation method of nano water-based silica sol for semiconductor polishing |
| CN113277522A (en) * | 2021-06-17 | 2021-08-20 | 航天特种材料及工艺技术研究所 | Light silica aerogel with ultrahigh transparency and ultralow haze, and preparation method and application thereof |
| CN113896204A (en) * | 2021-11-29 | 2022-01-07 | 苏州西丽卡电子材料有限公司 | Preparation method of ultra-high purity silica sol |
| CN114560468A (en) * | 2022-02-25 | 2022-05-31 | 金三江(肇庆)硅材料股份有限公司 | Silicon dioxide for chemical mechanical polishing and preparation method and application thereof |
| CN115353806A (en) * | 2022-08-01 | 2022-11-18 | 常州大学 | Silica sol with ultralow dispersion coefficient and preparation method and application thereof |
Non-Patent Citations (4)
| Title |
|---|
| ESCOBEDO, CAC ET.AL: "Preparation of size controlled nanometric spheres of colloidal silica for synthetic opal manufacture", 《ADVANCED STRUCTURAL MATERIALS II》, vol. 509, 31 December 2006 (2006-12-31), pages 187 - 192 * |
| XU, PC: "Preparation of silica sols and anti-reflective films with electrostatic self-assembly multilayer method", 《CHINESE JOURNAL OF CHEMICAL PHYSICS》, vol. 17, no. 2, 30 April 2004 (2004-04-30), pages 165 - 170 * |
| 王慕华: "《分析化学实验》", 31 August 2013, 大连海事大学出版社, pages: 146 * |
| 董贺: "四丁基氢氧化铵辅助的二氧化硅粒子尺寸与形貌调控", 《工程科技Ⅰ辑》, no. 10, 15 October 2017 (2017-10-15), pages 014 - 1 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1849379B (en) | Abrasive partilcle for chemical mechanical polishing | |
| WO2017206386A1 (en) | Polydispersed large particle silica sol and manufacturing method thereof | |
| CN107987732B (en) | Polishing solution for sapphire plane polishing and preparation method thereof | |
| EP0846741A1 (en) | Polishing composition | |
| Kao et al. | Synthesis and characterization of SiO2 nanoparticles and their efficacy in chemical mechanical polishing steel substrate | |
| EP0967260A1 (en) | Polishing composition and surface treating composition | |
| CN111040640A (en) | Composite abrasive chemical mechanical polishing slurry for silicon wafer substrate and preparation method thereof | |
| JP3782771B2 (en) | Abrasive grain and method for producing abrasive | |
| Xie et al. | High efficiency chemical mechanical polishing for silicon wafers using a developed slurry | |
| TWI651377B (en) | Chemical mechanical polishing liquid and preparation method thereof | |
| Li et al. | Development and characterization of a novel RE3+ doped Core-shell CeO2 abrasive system and its glass CMP investigations | |
| WO2014184709A2 (en) | Chemical-mechanical polishing compositions comprising n,n,n',n'-tetrakis-(2-hydroxypropyl)-ethylenediamine or methanesulfonic acid | |
| KR102660018B1 (en) | Abrasive for synthetic quartz glass substrate, manufacturing method thereof, and polishing method for synthetic quartz glass substrate | |
| CN115924922A (en) | Silica sol for chemical mechanical polishing and preparation method and application thereof | |
| JP6436018B2 (en) | Polishing slurry for oxide single crystal substrate and method for producing the same | |
| CN113773806B (en) | Nano silicon dioxide abrasive material and preparation method and application thereof | |
| CN114684846A (en) | Synthesis method and use method of cerium oxide | |
| KR20220060342A (en) | Method for producing composite particles in which the core is coated with cerium oxide particles, and composite particles manufactured thereby | |
| CN115466573B (en) | Polishing solution for monocrystalline silicon wafer and application thereof | |
| CN112778911B (en) | Application of surface-modified cerium oxide particles as polishing solution abrasive particles | |
| JP3751932B2 (en) | Abrasive grains, method for producing the same, and abrasive | |
| JPH1088111A (en) | Composition for grinding use | |
| KR102618202B1 (en) | Abrasives for synthetic quartz glass substrates and polishing methods for synthetic quartz glass substrates | |
| CN114525108B (en) | Silica sol active abrasive particles for chemical mechanical polishing and preparation method thereof | |
| KR20210067723A (en) | a manufacturing method of silica nanoparticle for chemical-mechanical polishing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |