CN115011257B - Tungsten polishing solution with POU service life improving function and application thereof - Google Patents
Tungsten polishing solution with POU service life improving function and application thereof Download PDFInfo
- Publication number
- CN115011257B CN115011257B CN202210768461.8A CN202210768461A CN115011257B CN 115011257 B CN115011257 B CN 115011257B CN 202210768461 A CN202210768461 A CN 202210768461A CN 115011257 B CN115011257 B CN 115011257B
- Authority
- CN
- China
- Prior art keywords
- chemical mechanical
- mechanical polishing
- tungsten chemical
- stabilizer
- polishing liquid
- 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.)
- Active
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 108
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 title claims abstract description 51
- 229910052721 tungsten Inorganic materials 0.000 title claims abstract description 51
- 239000010937 tungsten Substances 0.000 title claims abstract description 51
- 239000003381 stabilizer Substances 0.000 claims abstract description 43
- 239000000126 substance Substances 0.000 claims description 43
- 239000007788 liquid Substances 0.000 claims description 29
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 26
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical group OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 24
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 claims description 24
- 239000004094 surface-active agent Substances 0.000 claims description 18
- 150000004032 porphyrins Chemical class 0.000 claims description 14
- 239000007800 oxidant agent Substances 0.000 claims description 13
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 claims description 12
- 239000000377 silicon dioxide Substances 0.000 claims description 12
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims description 9
- 150000001735 carboxylic acids Chemical class 0.000 claims description 9
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 9
- 229940051841 polyoxyethylene ether Drugs 0.000 claims description 9
- 229920000056 polyoxyethylene ether Polymers 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 150000007524 organic acids Chemical group 0.000 claims description 7
- 230000001590 oxidative effect Effects 0.000 claims description 7
- 235000012239 silicon dioxide Nutrition 0.000 claims description 7
- 150000003983 crown ethers Chemical class 0.000 claims description 6
- 239000002738 chelating agent Substances 0.000 claims description 5
- 125000004122 cyclic group Chemical group 0.000 claims description 5
- 125000001183 hydrocarbyl group Chemical group 0.000 claims description 5
- ABLZXFCXXLZCGV-UHFFFAOYSA-N Phosphorous acid Chemical compound OP(O)=O ABLZXFCXXLZCGV-UHFFFAOYSA-N 0.000 claims description 4
- BAERPNBPLZWCES-UHFFFAOYSA-N (2-hydroxy-1-phosphonoethyl)phosphonic acid Chemical compound OCC(P(O)(O)=O)P(O)(O)=O BAERPNBPLZWCES-UHFFFAOYSA-N 0.000 claims description 3
- XEZNGIUYQVAUSS-UHFFFAOYSA-N 18-crown-6 Chemical compound C1COCCOCCOCCOCCOCCO1 XEZNGIUYQVAUSS-UHFFFAOYSA-N 0.000 claims description 3
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 claims description 3
- 229940120146 EDTMP Drugs 0.000 claims description 3
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 claims description 3
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 claims description 3
- YDONNITUKPKTIG-UHFFFAOYSA-N [Nitrilotris(methylene)]trisphosphonic acid Chemical compound OP(O)(=O)CN(CP(O)(O)=O)CP(O)(O)=O YDONNITUKPKTIG-UHFFFAOYSA-N 0.000 claims description 3
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 claims description 3
- BBGKDYHZQOSNMU-UHFFFAOYSA-N dicyclohexano-18-crown-6 Chemical compound O1CCOCCOC2CCCCC2OCCOCCOC2CCCCC21 BBGKDYHZQOSNMU-UHFFFAOYSA-N 0.000 claims description 3
- NFDRPXJGHKJRLJ-UHFFFAOYSA-N edtmp Chemical compound OP(O)(=O)CN(CP(O)(O)=O)CCN(CP(O)(O)=O)CP(O)(O)=O NFDRPXJGHKJRLJ-UHFFFAOYSA-N 0.000 claims description 3
- 150000002191 fatty alcohols Chemical class 0.000 claims description 3
- 239000002736 nonionic surfactant Substances 0.000 claims description 3
- 235000006408 oxalic acid Nutrition 0.000 claims description 3
- 235000002906 tartaric acid Nutrition 0.000 claims description 3
- 239000011975 tartaric acid Substances 0.000 claims description 3
- VFTFKUDGYRBSAL-UHFFFAOYSA-N 15-crown-5 Chemical compound C1COCCOCCOCCOCCO1 VFTFKUDGYRBSAL-UHFFFAOYSA-N 0.000 claims description 2
- 125000000373 fatty alcohol group Chemical group 0.000 claims description 2
- 229920006395 saturated elastomer Polymers 0.000 claims description 2
- 239000013543 active substance Substances 0.000 claims 2
- 239000002245 particle Substances 0.000 abstract description 15
- 230000002776 aggregation Effects 0.000 abstract description 6
- 238000005054 agglomeration Methods 0.000 abstract description 5
- 230000000052 comparative effect Effects 0.000 description 20
- 229910052751 metal Inorganic materials 0.000 description 7
- 239000002184 metal Substances 0.000 description 7
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 6
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 235000012431 wafers Nutrition 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 230000002035 prolonged effect Effects 0.000 description 3
- 239000012028 Fenton's reagent Substances 0.000 description 2
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 229910021485 fumed silica Inorganic materials 0.000 description 2
- MGZTXXNFBIUONY-UHFFFAOYSA-N hydrogen peroxide;iron(2+);sulfuric acid Chemical compound [Fe+2].OO.OS(O)(=O)=O MGZTXXNFBIUONY-UHFFFAOYSA-N 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 239000002105 nanoparticle Substances 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- -1 potassium ferricyanide Chemical group 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 150000003985 15-crown-5 derivatives Chemical group 0.000 description 1
- 239000003082 abrasive agent Substances 0.000 description 1
- 239000006061 abrasive grain Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000005380 borophosphosilicate glass Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 239000011164 primary particle Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 238000006748 scratching Methods 0.000 description 1
- 230000002393 scratching effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000003440 toxic substance Substances 0.000 description 1
Classifications
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F3/00—Brightening metals by chemical means
- C23F3/04—Heavy metals
- C23F3/06—Heavy metals with acidic solutions
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention discloses a tungsten polishing solution with an improved POU service life and application thereof. The two stabilizers are matched for use, so that the polishing solution has improved stability in POU, and particle agglomeration caused by poor stability is reduced, so that the surface quality of the polished surface is greatly improved.
Description
Technical Field
The invention relates to the technical field of chemical mechanical polishing, in particular to a tungsten polishing solution with improved POU service life and application thereof.
Background
With the gradual reduction of the size of semiconductor devices and the continuous increase of the number of metal layers, the planarization technology of the metal layers and the insulating dielectric layers becomes particularly critical. The planarization technology mainly comprises SOG (spin on glass) back etching, BPSG reflow, spin coating film layer, chemical Mechanical Polishing (CMP) and the like, wherein the CMP technology initiated by IBM corporation in the twentieth century 80 is widely applied as an effective method for global planarization.
In Chemical Mechanical Polishing (CMP), the upper surface of a substrate is in direct contact with a polishing pad and is rotated relative to the polishing pad under pressure, while an abrasive-containing mixture (commonly referred to as a polishing liquid) is applied to the surface of the polishing pad, and planarization of the substrate surface is accomplished by chemical etching of the polishing liquid and mechanical action of the abrasive.
It is known that in the polishing process of metal layers, a Metal Oxide (MO) having a relatively small hardness is usually formed on the metal surface by an oxidizing agent x ) The oxide layer is then mechanically removed by the abrasive action of the abrasive, producing a new metal surface that continues to be oxidized, and the process is repeated until polishing is complete.
Tungsten, which is one of the Chemical Mechanical Polishing (CMP) targets, has strong electromigration resistance at high current density, excellent hole filling capability, and can form good ohmic contact with silicon, so it can be used as a filling metal and diffusion barrier layer of contact windows and vias.
The existing chemical mechanical polishing method of tungsten mainly comprises the steps of oxidizing the surface of tungsten metal through Fenton reaction, as shown in formulas (1), (2) and (3), and removing a soft oxide film through mechanical grinding. U.S. patent No. 2002019128, japanese patent No. JP2001148360, etc. disclose a polishing composition comprising ferric nitrate as a catalyst and hydrogen peroxide as an oxidizing agent, which can greatly reduce the amount of ferric nitrate and at the same time avoid the formation of highly toxic substances by decomposition of potassium ferricyanide, as compared to the use of potassium ferricyanide and ferric nitrate as oxidizing agents in patent No. 6375552 and patent No. 5993686.
H 2 O 2 +Fe 3+ =Fe 2+ +O 2 +2H + (1)
Fe 3+ +H 2 O 2 =Fe 2+ +OH - +OH· (2)
6OH·+W+6H + =3H 2 O+WO 3 (3)
However, the use of Fenton's reagent still faces the problem of POU stability, namely, after hydrogen peroxide is added into the tungsten polishing solution at the point of use (POU), the hydrogen peroxide is rapidly decomposed along with the Fenton's reaction, and meanwhile Fe 3+ Forming multimers, guidesSo that large particles of the polishing solution appear and the POU service life is reduced. U.S. patent No. 7887715 changes the form of catalyst Fe present in the Fenton's reagent and avoids free Fe in solution by doping Fe nanoparticles into the abrasive 3+ To minimize Fe 3+ Impact on abrasive stability. However, the method has the advantages that the stabilizer is not used, the Fe nano particles catalyze hydrogen peroxide to be continuously decomposed, and the polishing solution POU has short service life.
U.S. Pat. Nos. 3,3779 and 37,35 both propose the addition of stabilizers to improve the stability of the slurry, the primary function of the stabilizers being to react with Fe 3+ Complexing and shielding Fe 3+ Adverse effect on silica abrasive stability. However, when hydrogen peroxide is added into the POU, the effect of the single stabilizer is greatly weakened, and the service life of the POU is hardly prolonged by simply relying on the stabilizer in the patent.
Therefore, a new tungsten chemical mechanical polishing solution is needed, so that the service life of the POU can be improved, the use of a client is more flexible and convenient, and meanwhile, particle agglomeration caused by poor stability is reduced, so that the surface quality of a polished surface is greatly improved.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a novel tungsten chemical mechanical polishing solution, so that the polishing solution has improved stability in POU, and particle agglomeration caused by poor stability is reduced, thereby greatly improving the surface quality of the polished surface.
It is another object of the present invention to provide the use of such a tungsten chemical mechanical polishing solution in tungsten chemical mechanical polishing.
In order to achieve the aim of the invention, the invention adopts the following technical scheme:
a tungsten polishing solution with improved POU life comprises a silicon dioxide abrasive, ferric nitrate, an oxidant, a stabilizer, a surfactant and water, wherein the stabilizer is Fe 3+ A stabilizer comprising a first stabilizer and a second stabilizer.
In a preferred embodiment, the tungsten chemical mechanical polishing liquid comprises 1 to 20% of silicon dioxide abrasive, 0.001 to 0.3% of ferric nitrate, 0.5 to 5% of oxidant, 0.001 to 0.2% of stabilizer, 0.001 to 0.2% of surfactant, and the balance of water in percentage by mass.
In a preferred embodiment, the tungsten chemical mechanical polishing liquid comprises 1-10% of silicon dioxide abrasive, 0.01-0.3% of ferric nitrate, 2-3% of oxidant, 0.02-0.2% of stabilizer, 0.01% -0.2% of surfactant and the balance of water in percentage by mass.
In a specific embodiment, the first stabilizer is an organic acid, such as an organic carboxylic acid or an organic phosphonic acid, for example selected from oxalic acid, malonic acid, succinic acid, citric acid or tartaric acid, or selected from aminotrimethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid, hydroxyethylidene diphosphonic acid, preferably the organic acid is an organic carboxylic acid, more preferably the organic carboxylic acid is malonic acid.
In a specific embodiment, the second stabilizer is a cyclic chelator, e.g. selected from porphyrins or crown ethers, preferably the second stabilizer is selected from porphyrins. The porphyrin is at least one or more of natural porphyrin and synthetic porphyrin, and the crown ether is at least one or more of 15-crown-5, 18-crown-6 and dicyclohexyl-18-crown-6.
In a specific embodiment, the first stabilizer is present in an amount of 0.01 to 0.2% and the second stabilizer is present in an amount of 0.0005 to 0.01% based on the total mass of the tungsten chemical mechanical polishing liquid.
The organic acid is Fe 3+ The use of the substance can cause part of Fe in polishing 3+ Released from the complex to ensure a polishing rate within an acceptable range, but when only organic acids are used, fe is due to its relatively weak binding force 3+ Aggregation may occur, thereby causing an increase in abrasive grain size. The cyclic chelating agent is Fe 3+ Is very good for stabilizing Fe by using the substance 3+ However, when only a cyclic chelating agent is used, fe is used as a component 3+ Difficult to release, resulting in unacceptable reductions in polishing rates. The two are combined to ensure that the polishing rate is not highOn the premise of obviously reducing, the stability is improved, and the POU service life is prolonged.
In a specific embodiment, the silica abrasive is a silica sol or fumed silica, preferably the silica abrasive is a silica sol.
In a specific embodiment, the surfactant is a nonionic surfactant; preferably, the surfactant is a fatty alcohol polyoxyethylene ether type surfactant, and the structural general formula of the surfactant is RO (CH) 2 CH 2 O) n H is formed; more preferably, the R group of the fatty alcohol-polyoxyethylene ether is C 12 (AEO-n for short), n=6-8; more preferably, the fatty alcohol-polyoxyethylene ether is AEO-7.
In a specific embodiment, the oxidizing agent is hydrogen peroxide; preferably, the pH of the tungsten chemical mechanical polishing solution is 2.0-2.5.
In another aspect of the present invention, the use of the aforementioned tungsten chemical mechanical polishing solution in tungsten chemical mechanical polishing.
By adopting the technical scheme, the invention has the following beneficial effects:
1) The service life of the polishing solution POU is prolonged;
2) Reducing agglomeration of silica abrasives in storage and POU;
3) Improving the polishing quality of the polished surface.
Detailed Description
The following examples will further illustrate the method provided by the present invention for a better understanding of the technical solution of the present invention, but the present invention is not limited to the examples listed but should also include any other known modifications within the scope of the claims of the present invention.
A tungsten chemical mechanical polishing solution comprises 1-20% by mass of silicon dioxide abrasive, 0.001-0.3% by mass of ferric nitrate, 0.5-5% by mass of oxidant, 0.001-0.3% by mass of stabilizer, 0.001-0.2% by mass of surfactant and the balance of water; wherein the stabilizer is Fe 3+ Stabilizers, including a first stabilizer and a second stabilizer.
In a preferred embodiment, the tungsten chemical mechanical polishing solution comprises, by mass, 1-10% of a silicon dioxide abrasive, 0.01-0.3% of ferric nitrate, 2-3% of an oxidizing agent, 0.02-0.2% of a stabilizing agent, 0.01% -0.2% of a surfactant, and the balance of water.
In particular, the first stabilizer is an organic acid, such as an organic carboxylic acid or an organic phosphonic acid, for example selected from oxalic acid, malonic acid, succinic acid, citric acid or tartaric acid, or selected from aminotrimethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid, hydroxyethylidene diphosphonic acid, preferably the organic acid is an organic carboxylic acid, more preferably the organic carboxylic acid is malonic acid; the second stabilizer is a cyclic chelating agent, for example selected from porphyrins or crown ethers, preferably the second stabilizer is selected from porphyrins.
The porphyrin can be natural porphyrin or synthetic porphyrin, and the crown ether can be 15-crown-5, 18-crown-6 or dicyclohexyl-18-crown-6, etc.
In a specific embodiment, the first stabilizer is present in an amount of 0.01-0.2%, including for example but not limited to 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, and the second stabilizer is present in an amount of 0.0005-0.01%, including for example but not limited to 0.0006%, 0.0007%, 0.0008%, 0.0009%, 0.001%, 0.0015%, 0.002%, 0.0025%, 0.003%, 0.0035%, 0.004%, 0.0045%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%.
The silica abrasive is silica sol or fumed silica, preferably silica sol, and is added in an amount generally ranging from 1% to 20% of the total mass of the polishing liquid, including, but not limited to, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, preferably, 1% to 10% of the total mass of the polishing liquid.
The silica sol has a particle size of 40-200nm, preferably 80-120nm, and may be any satisfactory silica sol, such as those available from Nissan Chemical, fuso, dupont, bayer, etc.
The ferric nitrate is generally added in an amount of 0.001% to 0.3% of the total mass of the polishing liquid, including, for example, but not limited to, 0.001%, 0.005%, 0.01%, 0.05%, 0.07%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, preferably, the ferric nitrate is added in an amount of 0.01% to 0.3% of the total mass of the polishing liquid.
The surfactant is nonionic surfactant, preferably fatty alcohol polyoxyethylene ether type surfactant, and has a structural formula of RO (CH) 2 CH 2 O) n H, wherein R is saturated or unsaturated C 12 -C 18 The hydrocarbon group of (2) may be a straight-chain hydrocarbon group or a branched hydrocarbon group; more preferably, the R group of the fatty alcohol-polyoxyethylene ether is C 12 (AEO-n for short), n=6-8; more preferably, the fatty alcohol-polyoxyethylene ether is AEO-7. The surfactant is generally added in an amount of 0.001% -0.2% of the total mass of the polishing liquid, including, for example, but not limited to, 0.001%, 0.005%, 0.01%, 0.012%, 0.013%, 0.014%, 0.015%, 0.017%, 0.2%, preferably, the surfactant is added in an amount of 0.01% -0.2% of the total mass of the polishing liquid.
The oxidizing agent is typically hydrogen peroxide and is added in an amount of 0.5-5%, including for example but not limited to 0.5%, 1%, 2%, 2.5%, 3%, 5%, typically added separately prior to use to avoid premature decomposition, preferably in an amount of 2-3% of the total polishing slurry.
Wherein the pH value of the tungsten chemical mechanical polishing solution is regulated to 2.0-2.5 by nitric acid or potassium hydroxide.
The invention is further illustrated, but not limited, by the following more specific examples.
Tables 1 and 2 show the components and contents of the tungsten polishing solutions of comparative examples 1 to 5 and examples 1 to 10 according to the present invention, and according to tables 1 and 2, the chemical mechanical polishing solutions were prepared by simple stirring and mixing, and after the uniform mixing, the pH was adjusted to 2.0 to 2.5 with nitric acid or KOH, and hydrogen peroxide was added before use, the uniform mixing was performed, and the balance was made up with water, to obtain each example of the present invention and comparative example.
Table 1 polishing liquid composition tables (containing no stabilizer) of comparative examples 1 to 5 and examples 1 to 10
Table 2 stabilizer composition tables of comparative examples 1 to 5 and examples 1 to 10
To verify the POU stability of the polishing solutions of the present invention, comparative examples 1 to 5, examples 1 to 10 were subjected to study comparison. After preparing the polishing solutions according to tables 1 and 2, the initial particle size was measured using a particle sizer of Malvern Panalytical (Malvern, UK), and the particle size of the polishing solution was again measured after storage at 40℃for 1 week and 2 weeks, respectively, and the results are shown in Table 3.
TABLE 3 POU particle size variation for comparative examples and examples
Polishing liquid | Primary particle size nm | Particle size nm after 1 week | Particle size nm after 2 weeks |
Comparative example 1 | 71.81 | 74.92 | 92.92 |
Comparative example 2 | 120.36 | 124.8 | 172.1 |
Comparative example 3 | 80.54 | 83.25 | 121.7 |
Comparative example 4 | 71.29 | 72.89 | 71.78 |
Comparative example 5 | 41.61 | 41.18 | 72.46 |
Example 1 | 40.12 | 40.85 | 41.59 |
Example 2 | 39.52 | 40.67 | 40.98 |
Example 3 | 71.26 | 71.87 | 72.10 |
Example 4 | 119.3 | 119.7 | 120.5 |
Example 5 | 79.46 | 80.32 | 80.29 |
Example 6 | 71.26 | 71.84 | 72.07 |
Example 7 | 72.08 | 72.36 | 72.89 |
Example 8 | 71.69 | 71.92 | 72.56 |
Example 9 | 71.82 | 72.37 | 73.02 |
Example 10 | 70.94 | 71.57 | 72.03 |
The results in Table 3 show that the average particle size of the abrasive particles changed within 2nm (no substantial change is considered due to the measurement error) after the polishing solutions of comparative examples 4-5 and examples 1-10 were stored at 40℃for 2 weeks, whereas the particle size of comparative examples 1-3 changed significantly, which means that the POU life was at least doubled, the abrasive agglomerates were greatly reduced, and the stability was greatly improved after the addition of the second stabilizer.
To verify the polishing effect of the polishing solutions of the present invention, the polishing solutions of comparative examples 1 to 5 and examples 1 to 10 were prepared in three portions, and polishing and detection of irregularities were performed at the initial stage of preparation, after 1 week of preparation, and after 2 weeks of preparation (at room temperature of 25 ℃), respectively. The polishing conditions were as follows: the polishing machine table is 12' reflexion LK, the polishing pad is IC1010, the polishing pressure is 4.0psi, the rotation speed of the polishing head and the polishing disk is 93/87rpm, the flow rate of the polishing liquid is 200mL/min, and the polishing time is 60s.
The conductivity of the tungsten wafer is measured by four-probe conductivity meters before and after polishing, so that the thickness of the tungsten wafer is calculated, and the tungsten polishing rate is obtained by dividing the difference between the thickness of the tungsten wafer before and after polishing by the polishing time. A Bruker Dektak XTL steppers was used to test non-uniformity (NU) of polished tungsten wafers.
Table 4 polishing effects of comparative examples 1 to 5 and examples 1 to 10
As shown in Table 4, the polishing rate of the examples was slightly lower than that of comparative examples 1 to 3, but still within the industrially acceptable range, because the polishing quality was more important for the polishing liquid, the polishing quality was greatly improved; whereas in comparative examples 4 to 5, the polishing rate was too small due to the close combination of the second stabilizer with the Fe catalyst. The polishing rates of the examples after 1 and 2 weeks of placement were not significantly different from the new formulation, while the polishing rates of comparative examples 1-3 after 1 week of placement were significantly increased, probably due to the fact that the decomposition of hydrogen peroxide did not have a significant effect on the chemistry and the increase in the large particle abrasive in the polishing liquid resulted in an increase in mechanical friction. Meanwhile, the polishing rate of comparative examples 1 to 3 was significantly lowered after 2 weeks of standing because hydrogen peroxide was decomposed in large amounts, resulting in insufficient chemical action in polishing. Correspondingly, the unevenness (NU) in the comparative polishing increased significantly with time, probably due to the increased probability of scratching the tungsten surface being polished after the agglomeration of the abrasive, resulting in a significantly decreased surface quality, while the examples maintained excellent surface polishing quality over a 2-week standing period.
In conclusion, when the tungsten polishing solution is applied to the chemical mechanical polishing of the tungsten-containing wafer, the tungsten polishing solution has the advantages of long POU service life and high polishing evenness, can be stored for a long time after hydrogen peroxide is added, and has higher commercial value.
While the present invention has been described in detail through the foregoing description of the preferred embodiment, it should be understood that the foregoing description is not to be considered as limiting the invention. Those skilled in the art will appreciate that certain modifications and adaptations of the invention are possible and can be made under the teaching of the present specification. Such modifications and adaptations are intended to be within the scope of the present invention as defined in the appended claims.
Claims (14)
1. The tungsten chemical mechanical polishing solution is characterized by comprising 1-20% of silicon dioxide abrasive, 0.001-0.3% of ferric nitrate, 0.5-5% of oxidant, 0.001-0.2% of stabilizer, 0.001-0.2% of surfactant and the balance of water, wherein the stabilizer is Fe 3+ A stabilizer comprising a first stabilizer and a second stabilizer; the first stabilizer is an organic acid selected from an organic carboxylic acid or an organic phosphonic acid; the second stabilizer is a cyclic chelating agent selected from porphyrins or crown ethers.
2. The tungsten chemical mechanical polishing liquid according to claim 1, wherein the tungsten chemical mechanical polishing liquid comprises 1-10% of silicon dioxide abrasive, 0.01-0.3% of ferric nitrate, 2-3% of oxidant, 0.02-0.2% of stabilizer, 0.01% -0.2% of surfactant and the balance of water in percentage by mass.
3. The tungsten chemical mechanical polishing liquid according to claim 1 or 2, wherein the organic carboxylic acid is at least one or more selected from oxalic acid, malonic acid, succinic acid, citric acid and tartaric acid; the organic phosphonic acid is at least one or more selected from amino trimethylene phosphonic acid, ethylenediamine tetramethylene phosphonic acid and hydroxyethylidene diphosphonic acid.
4. A tungsten chemical mechanical polishing solution according to claim 3, wherein the organic carboxylic acid is malonic acid.
5. The tungsten chemical mechanical polishing liquid according to claim 1 or 2, wherein the content of the first stabilizer is 0.01 to 0.2% based on the total mass of the tungsten chemical mechanical polishing liquid.
6. The tungsten chemical mechanical polishing liquid according to claim 1 or 2, wherein the porphyrin is at least one or more of natural porphyrin and synthetic porphyrin, and the crown ether is at least one or more of 15-crown-5, 18-crown-6 and dicyclohexyl-18-crown-6.
7. The tungsten chemical mechanical polishing liquid according to claim 6, wherein the content of the second stabilizer is 0.0005 to 0.01% based on the total mass of the tungsten chemical mechanical polishing liquid.
8. The tungsten chemical mechanical polishing liquid according to claim 1 or 2, wherein the surfactant is a nonionic surfactant.
9. The tungsten chemical mechanical polishing solution according to claim 8, wherein the surfactant is a fatty alcohol polyoxyethylene ether type surfactant having a general structural formula RO (CH) 2 CH 2 O) n H, R is a saturated or unsaturated C12-C18 hydrocarbon group, which is a straight or branched hydrocarbon group, n=6-8.
10. The tungsten chemical mechanical polishing liquid according to claim 9, wherein the R group of the fatty alcohol polyoxyethylene ether type active agent is C12, n=6 to 8.
11. The tungsten chemical mechanical polishing solution according to claim 10, wherein the R group of the fatty alcohol polyoxyethylene ether type active agent is C12, n=7.
12. A tungsten chemical mechanical polishing solution according to claim 1 or 2, wherein the oxidizing agent is hydrogen peroxide.
13. The tungsten chemical mechanical polishing liquid according to claim 1 or 2, wherein the pH of the tungsten chemical mechanical polishing liquid is 2.0 to 2.5.
14. Use of the tungsten chemical mechanical polishing liquid according to any one of claims 1 to 13 in tungsten chemical mechanical polishing.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210768461.8A CN115011257B (en) | 2022-06-30 | 2022-06-30 | Tungsten polishing solution with POU service life improving function and application thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210768461.8A CN115011257B (en) | 2022-06-30 | 2022-06-30 | Tungsten polishing solution with POU service life improving function and application thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
CN115011257A CN115011257A (en) | 2022-09-06 |
CN115011257B true CN115011257B (en) | 2023-12-19 |
Family
ID=83079533
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210768461.8A Active CN115011257B (en) | 2022-06-30 | 2022-06-30 | Tungsten polishing solution with POU service life improving function and application thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN115011257B (en) |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0653198A (en) * | 1992-06-03 | 1994-02-25 | Hitachi Ltd | Cleaning agent and cleaning method for semiconductor substrate using same |
CN101955731A (en) * | 2009-07-13 | 2011-01-26 | 安集微电子(上海)有限公司 | Chemical mechanical polishing solution |
JP2011119405A (en) * | 2009-12-02 | 2011-06-16 | Shin Etsu Handotai Co Ltd | Abrasive for polishing silicon wafer and method of polishing silicon wafer |
CN102666760A (en) * | 2009-11-11 | 2012-09-12 | 可乐丽股份有限公司 | Slurry for chemical mechanical polishing and polishing method for substrate using same |
CN102898950A (en) * | 2011-07-27 | 2013-01-30 | 安集微电子(上海)有限公司 | Chemical mechanical polishing solution |
CN107189695A (en) * | 2017-04-15 | 2017-09-22 | 浙江晶圣美纳米科技有限公司 | A kind of polishing fluid for being efficiently applied to stainless steel lining bottom CMP process |
CN107523219A (en) * | 2016-06-16 | 2017-12-29 | 弗萨姆材料美国有限责任公司 | Chemical Mechanical Polishing (CMP) of Cobalt-Containing Substrates |
TW201940565A (en) * | 2018-02-15 | 2019-10-16 | 日商三菱化學股份有限公司 | Polyester film for dry film resist substrate |
CN113583572A (en) * | 2021-07-09 | 2021-11-02 | 万华化学集团电子材料有限公司 | Tungsten chemical mechanical polishing solution and application thereof |
CN113597456A (en) * | 2018-12-31 | 2021-11-02 | Cmc材料股份有限公司 | Composition for tungsten chemical mechanical polishing |
CN115820132A (en) * | 2022-11-23 | 2023-03-21 | 嘉兴市小辰光伏科技有限公司 | Chain type alkali polishing process additive and application thereof |
-
2022
- 2022-06-30 CN CN202210768461.8A patent/CN115011257B/en active Active
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0653198A (en) * | 1992-06-03 | 1994-02-25 | Hitachi Ltd | Cleaning agent and cleaning method for semiconductor substrate using same |
CN101955731A (en) * | 2009-07-13 | 2011-01-26 | 安集微电子(上海)有限公司 | Chemical mechanical polishing solution |
CN102666760A (en) * | 2009-11-11 | 2012-09-12 | 可乐丽股份有限公司 | Slurry for chemical mechanical polishing and polishing method for substrate using same |
JP2011119405A (en) * | 2009-12-02 | 2011-06-16 | Shin Etsu Handotai Co Ltd | Abrasive for polishing silicon wafer and method of polishing silicon wafer |
CN102898950A (en) * | 2011-07-27 | 2013-01-30 | 安集微电子(上海)有限公司 | Chemical mechanical polishing solution |
CN107523219A (en) * | 2016-06-16 | 2017-12-29 | 弗萨姆材料美国有限责任公司 | Chemical Mechanical Polishing (CMP) of Cobalt-Containing Substrates |
CN107189695A (en) * | 2017-04-15 | 2017-09-22 | 浙江晶圣美纳米科技有限公司 | A kind of polishing fluid for being efficiently applied to stainless steel lining bottom CMP process |
TW201940565A (en) * | 2018-02-15 | 2019-10-16 | 日商三菱化學股份有限公司 | Polyester film for dry film resist substrate |
CN113597456A (en) * | 2018-12-31 | 2021-11-02 | Cmc材料股份有限公司 | Composition for tungsten chemical mechanical polishing |
CN113583572A (en) * | 2021-07-09 | 2021-11-02 | 万华化学集团电子材料有限公司 | Tungsten chemical mechanical polishing solution and application thereof |
CN115820132A (en) * | 2022-11-23 | 2023-03-21 | 嘉兴市小辰光伏科技有限公司 | Chain type alkali polishing process additive and application thereof |
Also Published As
Publication number | Publication date |
---|---|
CN115011257A (en) | 2022-09-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP4075985B2 (en) | Polishing composition and polishing method using the same | |
JP5038199B2 (en) | Composition for oxide CMP | |
US6355075B1 (en) | Polishing composition | |
EP1405886B1 (en) | Polishing composition | |
US7842193B2 (en) | Polishing liquid | |
JPH08510437A (en) | Polishing compound and polishing method | |
US9834705B2 (en) | Polishing slurry and method of polishing substrate using the same | |
EP1489650B1 (en) | Polishing composition and method for forming wiring structure | |
CN103228756B (en) | A kind of tungsten grinding slurry composition for CMP | |
CN113583572B (en) | Tungsten chemical mechanical polishing solution and application thereof | |
TW202126722A (en) | Chemical mechanical polishing slurry | |
KR20130133968A (en) | Polishing composition and slurry composition comprising the same | |
CN115011257B (en) | Tungsten polishing solution with POU service life improving function and application thereof | |
CN102533121A (en) | Chemically mechanical polishing solution for polishing tungsten | |
TWI838447B (en) | Chemical-mechanical polishing slurry for polishing tungsten | |
CN114686106A (en) | Chemical mechanical polishing solution for tungsten polishing | |
CN113802122B (en) | Tungsten plug chemical mechanical polishing solution for reducing pitting corrosion and application thereof | |
CN113604154B (en) | Tungsten plug chemical mechanical polishing solution, preparation method and application thereof | |
CN115505932B (en) | Tungsten chemical mechanical polishing solution and application thereof | |
KR100442549B1 (en) | Slurry Composition for Chemical Mechanical Polishing of Metal having Enhanced Polishing Ability and Improved Stability and a Method for Preparing the Slurry Composition | |
CN117947422A (en) | Long-time high-speed tungsten chemical mechanical polishing solution and application thereof | |
CN112399999B (en) | Chemical mechanical polishing composition, chemical mechanical polishing slurry and substrate polishing method | |
KR20180064019A (en) | Chemical-mechanical polishing slurry composition and method for manufacturing semiconductor by using the same | |
CN116254058A (en) | Chemical mechanical polishing solution and application thereof | |
CN114686114A (en) | Chemical mechanical polishing solution and use method thereof |
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 | ||
GR01 | Patent grant | ||
GR01 | Patent grant |