WO2011097954A1 - 一种用于钨化学机械抛光方法 - Google Patents
一种用于钨化学机械抛光方法 Download PDFInfo
- Publication number
- WO2011097954A1 WO2011097954A1 PCT/CN2011/000205 CN2011000205W WO2011097954A1 WO 2011097954 A1 WO2011097954 A1 WO 2011097954A1 CN 2011000205 W CN2011000205 W CN 2011000205W WO 2011097954 A1 WO2011097954 A1 WO 2011097954A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- mechanical polishing
- chemical mechanical
- polishing method
- polishing
- tungsten
- Prior art date
Links
- 238000005498 polishing Methods 0.000 title claims abstract description 145
- 239000000126 substance Substances 0.000 title claims abstract description 74
- 238000000034 method Methods 0.000 title claims abstract description 47
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 title claims abstract description 44
- 229910052721 tungsten Inorganic materials 0.000 title claims abstract description 44
- 239000010937 tungsten Substances 0.000 title claims abstract description 44
- 239000007800 oxidant agent Substances 0.000 claims abstract description 31
- 239000002243 precursor Substances 0.000 claims abstract description 21
- 150000002978 peroxides Chemical class 0.000 claims abstract description 11
- 230000003068 static effect Effects 0.000 claims abstract description 9
- 239000003112 inhibitor Substances 0.000 claims abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000003002 pH adjusting agent Substances 0.000 claims abstract description 6
- 150000003623 transition metal compounds Chemical group 0.000 claims abstract description 5
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 100
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical group [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims description 42
- 239000007788 liquid Substances 0.000 claims description 28
- 230000001590 oxidative effect Effects 0.000 claims description 28
- -1 ferrous transition metal salt Chemical class 0.000 claims description 27
- 229910001961 silver nitrate Inorganic materials 0.000 claims description 21
- 239000007789 gas Substances 0.000 claims description 17
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 11
- 239000012190 activator Substances 0.000 claims description 11
- 229910052723 transition metal Inorganic materials 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 10
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical group [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 claims description 8
- 150000007524 organic acids Chemical class 0.000 claims description 8
- 229940120146 EDTMP Drugs 0.000 claims description 7
- 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 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 6
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical group [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 claims description 6
- 239000012425 OXONE® Substances 0.000 claims description 5
- ROOXNKNUYICQNP-UHFFFAOYSA-N ammonium peroxydisulfate Substances [NH4+].[NH4+].[O-]S(=O)(=O)OOS([O-])(=O)=O ROOXNKNUYICQNP-UHFFFAOYSA-N 0.000 claims description 5
- VAZSKTXWXKYQJF-UHFFFAOYSA-N ammonium persulfate Chemical compound [NH4+].[NH4+].[O-]S(=O)OOS([O-])=O VAZSKTXWXKYQJF-UHFFFAOYSA-N 0.000 claims description 5
- 229910001870 ammonium persulfate Inorganic materials 0.000 claims description 5
- HJKYXKSLRZKNSI-UHFFFAOYSA-I pentapotassium;hydrogen sulfate;oxido sulfate;sulfuric acid Chemical compound [K+].[K+].[K+].[K+].[K+].OS([O-])(=O)=O.[O-]S([O-])(=O)=O.OS(=O)(=O)O[O-].OS(=O)(=O)O[O-] HJKYXKSLRZKNSI-UHFFFAOYSA-I 0.000 claims description 5
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 5
- 239000000377 silicon dioxide Substances 0.000 claims description 5
- 150000002696 manganese Chemical class 0.000 claims description 4
- 229910000420 cerium oxide Inorganic materials 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 3
- 150000002697 manganese compounds Chemical class 0.000 claims description 3
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 claims description 3
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Natural products P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 claims description 2
- 150000007529 inorganic bases Chemical class 0.000 claims description 2
- 150000007522 mineralic acids Chemical group 0.000 claims description 2
- 150000007530 organic bases Chemical class 0.000 claims description 2
- 229910000073 phosphorus hydride Inorganic materials 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims 2
- 229910052751 metal Inorganic materials 0.000 abstract description 21
- 239000002184 metal Substances 0.000 abstract description 21
- 150000003839 salts Chemical class 0.000 abstract description 3
- 230000007704 transition Effects 0.000 abstract description 3
- 239000003082 abrasive agent Substances 0.000 abstract description 2
- 239000003795 chemical substances by application Substances 0.000 abstract 3
- 230000000052 comparative effect Effects 0.000 description 22
- 229910052709 silver Inorganic materials 0.000 description 20
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 19
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 19
- 229910017604 nitric acid Inorganic materials 0.000 description 19
- 229910052739 hydrogen Inorganic materials 0.000 description 18
- 239000001257 hydrogen Substances 0.000 description 18
- 238000005502 peroxidation Methods 0.000 description 18
- 239000011572 manganese Substances 0.000 description 17
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 16
- 230000000694 effects Effects 0.000 description 16
- 239000004332 silver Substances 0.000 description 14
- 229940099596 manganese sulfate Drugs 0.000 description 13
- 239000011702 manganese sulphate Substances 0.000 description 13
- 235000007079 manganese sulphate Nutrition 0.000 description 13
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 13
- 238000006243 chemical reaction Methods 0.000 description 12
- 229910052742 iron Inorganic materials 0.000 description 12
- 229910052748 manganese Inorganic materials 0.000 description 12
- 229910052710 silicon Inorganic materials 0.000 description 11
- 239000010703 silicon Substances 0.000 description 11
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 10
- 238000000354 decomposition reaction Methods 0.000 description 10
- 238000000227 grinding Methods 0.000 description 9
- 229910001437 manganese ion Inorganic materials 0.000 description 9
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 description 8
- 230000003197 catalytic effect Effects 0.000 description 8
- 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 description 8
- 230000009471 action Effects 0.000 description 7
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 6
- 230000004888 barrier function Effects 0.000 description 6
- 230000005284 excitation Effects 0.000 description 6
- 230000005281 excited state Effects 0.000 description 6
- 238000009472 formulation Methods 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 239000003381 stabilizer Substances 0.000 description 6
- 150000003624 transition metals Chemical class 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- 229910021645 metal ion Inorganic materials 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 238000010979 pH adjustment Methods 0.000 description 4
- 238000007517 polishing process Methods 0.000 description 4
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- FOIXSVOLVBLSDH-UHFFFAOYSA-N Silver ion Chemical compound [Ag+] FOIXSVOLVBLSDH-UHFFFAOYSA-N 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 3
- 239000003054 catalyst Substances 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 239000008367 deionised water Substances 0.000 description 3
- 229910021641 deionized water Inorganic materials 0.000 description 3
- 229910001882 dioxygen Inorganic materials 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229960005191 ferric oxide Drugs 0.000 description 3
- 235000005985 organic acids Nutrition 0.000 description 3
- 239000010944 silver (metal) Substances 0.000 description 3
- APSBXTVYXVQYAB-UHFFFAOYSA-M sodium docusate Chemical compound [Na+].CCCCC(CC)COC(=O)CC(S([O-])(=O)=O)C(=O)OCC(CC)CCCC APSBXTVYXVQYAB-UHFFFAOYSA-M 0.000 description 3
- 0 *CC(*)[C@@]1C(*C*I)CCCC1 Chemical compound *CC(*)[C@@]1C(*C*I)CCCC1 0.000 description 2
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- LELOWRISYMNNSU-UHFFFAOYSA-N hydrogen cyanide Chemical compound N#C LELOWRISYMNNSU-UHFFFAOYSA-N 0.000 description 2
- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 2
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 description 2
- 239000005416 organic matter Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 229910052990 silicon hydride Inorganic materials 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 229910001930 tungsten oxide Inorganic materials 0.000 description 2
- ZNOKGRXACCSDPY-UHFFFAOYSA-N tungsten trioxide Chemical compound O=[W](=O)=O ZNOKGRXACCSDPY-UHFFFAOYSA-N 0.000 description 2
- DZKDPOPGYFUOGI-UHFFFAOYSA-N tungsten(iv) oxide Chemical compound O=[W]=O DZKDPOPGYFUOGI-UHFFFAOYSA-N 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- VZSRBBMJRBPUNF-UHFFFAOYSA-N 2-(2,3-dihydro-1H-inden-2-ylamino)-N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]pyrimidine-5-carboxamide Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C(=O)NCCC(N1CC2=C(CC1)NN=N2)=O VZSRBBMJRBPUNF-UHFFFAOYSA-N 0.000 description 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- WAEMQWOKJMHJLA-UHFFFAOYSA-N Manganese(2+) Chemical compound [Mn+2] WAEMQWOKJMHJLA-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000003490 calendering Methods 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 230000002925 chemical effect Effects 0.000 description 1
- 239000008139 complexing agent Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 229910021485 fumed silica Inorganic materials 0.000 description 1
- 239000008266 hair spray Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000005984 hydrogenation reaction Methods 0.000 description 1
- TUJKJAMUKRIRHC-UHFFFAOYSA-N hydroxyl Chemical compound [OH] TUJKJAMUKRIRHC-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 1
- 230000009916 joint effect Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 238000005580 one pot reaction Methods 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000006174 pH buffer Substances 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 239000012286 potassium permanganate Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 150000003376 silicon Chemical class 0.000 description 1
- SBEQWOXEGHQIMW-UHFFFAOYSA-N silicon Chemical compound [Si].[Si] SBEQWOXEGHQIMW-UHFFFAOYSA-N 0.000 description 1
- 238000002798 spectrophotometry method Methods 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
- H01L21/321—After treatment
- H01L21/32115—Planarisation
- H01L21/3212—Planarisation by chemical mechanical polishing [CMP]
-
- 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
Definitions
- the invention relates to a method for chemical mechanical polishing of tungsten, in particular to a method for chemical mechanical polishing of tungsten with a chemical containing an activator.
- CMP chemical machine tt ⁇ polishing
- CMP Chemical mechanical polishing
- It usually consists of a polishing table with a polishing pad and a polishing head for carrying the chip.
- the polishing head holds the chip and then presses the front side of the chip against the polishing pad.
- the polishing head moves linearly on the polishing pad or in the same direction of motion as the polishing table.
- the slurry containing the abrasive is dropped onto the polishing pad and laid flat on the polishing pad by centrifugation.
- the surface of the chip achieves global planarization under both mechanical and chemical effects.
- CMP chemical mechanical polishing
- Metal tungsten one of the chemical polishing (CMP) targets, has high electron current resistance at high current density and can form a good ohmic contact with silicon, so it can be used as a filler metal for contact windows and via holes. Diffusion barrier.
- CMP tungsten chemical mechanical polishing
- two methods have been used to date: oxidants Direct oxidation processes (e.g., US 5,340, 370, US 5, 527, 742, US Pat. No. 6,008, 119, US Pat. No. 6, 284, 415, US Pat. No. 5,225, 034, US Pat. No. 5,354, 490), and catalyzed methods (for example, US Pat. No. 5,958,288, US Pat. No. 5,980,775, and US Pat.
- Direct oxidation processes e.g., US 5,340, 370, US 5, 527, 742, US Pat. No. 6,008, 119, US Pat. No. 6, 284, 415, US Pat. No. 5,225, 034, US Pat. No. 5,354, 490
- catalyzed methods for example, US Pat. No. 5,958,288, US Pat. No. 5,980,775, and US Pat.
- U.S. Patent 5,340,370 discloses a formulation for tungsten chemical mechanical polishing (CMP) containing 0.1 M potassium ferricyanide, 5% silica, and acetate as a pH buffer. Since potassium ferricyanide decomposes highly toxic hydrogen cyanide under ultraviolet light or sunlight, and in an acidic medium, it is widely used.
- CMP chemical mechanical polishing
- U.S. Patent No. 5,527,423, U.S. Patent No. 6,008,119, U.S. Patent No. 6,284,151, et al. discloses the use of the Fe (N0 3 ) 3 , alumina system for tungsten mechanical polishing (CMP).
- the polishing system has an advantage in terms of static etch rate, but due to the use of alumina as an abrasive, there are significant deficiencies in product defects.
- the high concentration of ferric nitrate makes the pH of the polishing liquid strongly acidic, which seriously corrodes the equipment, and at the same time, generates rust and contaminates the polishing pad.
- high concentrations of iron ions act as mobile metal ions, which seriously reduce the reliability of semiconductor components.
- U.S. Patent No. 5,225, 034, U.S. Patent No. 5,354, 490 discloses the use of hydrogen peroxide and silver nitrate in combination as an oxidizing agent for metal polishing.
- the amount of silver nitrate is large (greater than 2%), resulting in excessive polishing fluid cost, unstable abrasive, easy precipitation, hydrogen peroxide Rapid decomposition and other issues.
- U.S. Patent No. 5,958,288 discloses the use of ferric nitrate as a catalyst and hydrogen peroxide as an oxidant for tungsten chemical mechanical polishing. It should be noted that in this patent, a variety of transition metal elements are mentioned, and only iron elements have been experimentally proven to be significantly effective. Therefore, the actual implementation effect and scope of the invention are limited. Although this method greatly reduces the amount of ferric nitrate, since the iron ion still exists and the Fenton reaction occurs with the hydrogen peroxide, the hydrogen peroxide rapidly and violently decomposes, so the polishing solution has a problem of poor stability.
- U.S. Patent No. 5,980,775 and U.S. Patent No. 6,068,787 incorporates an organic acid as a stabilizer to improve the rate of decomposition of hydrogen peroxide.
- the pH of the polishing solution is low (usually below about 2.7), causing corrosion of the equipment.
- the polishing solution containing iron nitrate has a narrow pH adjustment range. Because when the pH is higher than 2.7, the ferric nitrate will be hydrolyzed to form a precipitate of iron hydroxide, which will cause the polishing solution to fail, which limits its pH adjustment ability.
- the addition of organic acids increases the organic matter content (COD) in the polishing waste liquid, which is not conducive to environmental protection.
- the oxidant 3 ⁇ 4 the stability problem of oxygen water still exists.
- organic acid as a stabilizer improves the decomposition rate of hydrogen peroxide, the decomposition rate is still high, and the hydrogen peroxide concentration is usually reduced by more than 10% in two weeks. As a result, the polishing speed is lowered and the polishing liquid is gradually decomposed and failed.
- Chinese Patent No. CN 1966 594 A discloses a method of adding an etch inhibitor to the above catalytic system, but since the catalyst used is still iron, the problem of easy decomposition of hydrogen peroxide and poor stability still exists.
- the above documents and patents mainly use two methods for chemical mechanical polishing of tungsten: direct oxidation of oxidant and catalytic method.
- the chemical mechanical polishing method of tungsten provided by the present invention is a method utilizing an "excited state".
- the main differences between the present invention and the direct oxidation process as well as the catalytic process are:
- the invention involves at least two steps of reaction: In the first step, the activator begins to excite the oxidant precursor
- the second step the excited oxidant deoxidizes tungsten.
- the direct oxidation method and the catalytic method are only one-step reactions.
- the invention relates to at least three chemical components: a peroxide (A), a precursor of a strong oxidant (metal B), and a metal C in the activator, the three chemical components themselves, and any two of them Combination: A+B, A+C, B+C will not significantly improve the polishing speed of tungsten. Only when the three are present (A+B+C) will it produce unexpected effects.
- the Fenton reaction between iron and hydrogen peroxide produces a strong oxidizing hydroxyl radical, which is beneficial to increase the polishing speed of tungsten.
- the technical problem solved by the present invention is to excite a precursor of a strong oxidant with an activator, thereby significantly increasing the chemical mechanical polishing speed of tungsten.
- the method for tungsten chemical mechanical polishing of the present invention is to chemically mechanically polish tungsten with a chemical mechanical polishing liquid containing an activator, which also contains a strong oxidant precursor.
- the chemical mechanical polishing liquid further contains water and an abrasive.
- the abrasive is selected from one or more of fumed silica, silica sol, alumina, and/or cerium oxide.
- the abrasive has a mass percentage of 0.1 to 20%.
- the strong oxidant precursor is a transition metal compound.
- the transition metal compound is a divalent manganese compound.
- the divalent manganese compound is an organic and/or inorganic manganese salt.
- the inorganic manganese salt is manganese nitrate and/or manganese sulfate.
- the strong oxidant precursor has a mass percentage of 0.05 to 1%.
- the activator is a composition composed of a non-ferrous transition metal salt and a peroxide.
- the peroxide is one or more of ammonium persulfate, potassium monopersulfate and/or hydrogen peroxide.
- the peroxide has a mass percentage of 0.1 to 10%.
- the non-ferrous transition element metal salt is a silver salt.
- the silver salt is silver nitrate.
- the silver salt has a mass percentage of 0.05 to 2%.
- the chemical mechanical polishing liquid further contains a pH adjusting agent, and the pH adjusting agent is an inorganic or organic acid, an inorganic or organic base.
- the chemical mechanical polishing liquid has a pH of 0.5 to 4.5.
- the chemical mechanical polishing fluid also contains an inhibitor containing a static etch rate.
- the static etch rate inhibitor is an organic phosphine compound.
- the organophosphine compound is ethylenediaminetetramethylene phosphonic acid (EDTMP).
- ETMP ethylenediaminetetramethylene phosphonic acid
- Excitation in the present invention means that the oxidant does not have strong oxidizing property before being “excited”, but can exhibit a very strong oxidizing ability (polishing speed) after "excited”; the oxidizing agent is "excited""Before and after, the chemical price has not changed.
- the formulation used in the present invention is functionally divided into at least two parts: a precursor of a strong oxidizing agent and an activator.
- the precursor of the strong oxidant is a soluble, low-valent metal ion which is self-oxidizing weakly, but which exhibits very strong oxidizing properties in the high valence state.
- divalent manganese ions have a standard electrode potential of -1.029 (V) and a very weak oxidizing power.
- the seven-valent manganese such as potassium permanganate
- the activator may be composed of two or more components of two or more. The result of their joint action is to excite the "precursor of strong oxidants".
- the specific composition of the hair spray includes: oxidant + transition metal.
- a typical activator in the present invention is "hydrogen peroxide + silver ion". Hydrogen peroxide can "excite” a "strong oxidant precursor" (for example, a divalent manganese ion) to a "excited state" under the action of silver ions.
- the excited manganese ions exhibit a very strong oxidizing power (polishing speed) when they are contacted with the material to be polished (tungsten).
- This polishing process is shown in Figure 2; the polishing process of the conventional Fe-H 2 2 polishing system is shown in Figure 3.
- monovalent silver ions are oxidized to a "transition state" of Ag*, which oxidizes divalent manganese to an excited state of Mn*, the excited state of Mn* contact
- it reaches the surface of tungsten, it exhibits strong oxidizability, oxidizes tungsten into tungsten dioxide and trioxide Tungsten, the tungsten oxide is removed under the mechanical action of the abrasive. Thereby achieving continuous polishing.
- This polishing process is significantly different from the Fe-H 2 0 2 polishing system (Fig. 3):
- the chemical mechanical polishing method of the present invention can be free of “machines (stabilizers, such as organic acids, etc.). Therefore, the content of organic matter (COD emissions) in the polishing waste liquid is lowered, which is environmentally friendly.
- the chemical mechanical polishing liquid used has a wider pH adjustment range, and the corrosion of the device can be reduced by raising the pH value, and is applied to a wider range. CMP field.
- FIG. 1 is a schematic diagram of an "energy barrier" of ammonium sulfate, potassium monopersulfate and hydrogen peroxide.
- Figure 2 is a schematic view showing the polishing of the chemical mechanical polishing liquid of the present invention.
- Figure 3 is a schematic view showing the polishing of a conventional Fe-H 2 2 polishing system.
- Fig. 4 is a schematic view showing the decomposition rate of hydrogen peroxide in the chemical mechanical polishing liquid of Example 6 and the conventional Fe-H 2 2 2 .
- Table 1 shows the formulations of Examples 1 to 16 and Comparative Examples 1 to 4 of the chemical mechanical polishing liquid of the present invention, which are uniformly mixed in deionized water according to the components and contents thereof listed in Table 1, and adjusted with a pH adjusting agent. To the desired pH: a chemical mechanical polishing solution can be prepared. : Table 1 Chemical mechanical polishing liquid of the present invention Examples 1 to 16 and Comparative Examples 1 to 4
- Example 1 1.3 Peroxidation 5 Silver nitrate 0.2 Sulfur Meng 0.5 Dilute nitric acid 2.5
- Example 2 Gas phase dioxane 1.3 Peroxidation 5 Silver nitrate 0.2 Manganese nitrate 0.25 Dilute nitric acid 2.5
- Example 3 1.3 Peroxidation 5 Silver nitrate 0.05 Manganese sulfate 0.5
- Example 4 1.3 5 Silver nitrate 0.1 Manganese nitrate 0.5 Dilute nitric acid 2.5
- Example 6 Gas phase dioxane 1.3 Peroxidation 2 Silver nitrate 0.2 Manganese sulfate 0.5 Dilute nitric acid 2.5 Silicon silicon Hydrogen
- Example 8 1.3 Peroxidation 5 Silver nitrate 0.5 Manganese nitrate 0.05 Dilute nitric acid 2.5 Silicon. Hydrogen
- Example 9 1 Silver nitrate 0.2 Manganese sulfate 0.5
- Example 7 Silica sol 0.5 Peroxidation 10 Silver nitrate 1 Manganese sulfate 0.25 Dilute nitric acid 0.5 Hydrogen
- Example 10 Silica sol 10 Peroxidation 1 Silver nitrate 2 Manganese nitrate 0.25 Potassium hydroxide 4.5 Hydrogen
- Example 1 Silica sol 0.1 0.1 Citric acid 0.1 Manganese sulfate 0.25
- Example 14 Gas phase dioxane 1.3 Peroxidation 2 Silver nitrate 0.2 Manganese sulfate 0.5 EDTMP
- Example 16 Gas phase dioxane 1.3 Peroxidation 2 Silver nitrate 0.2 Manganese sulfate 0.5 500 2.5 Silicon Dioxide
- Polishing machine is Logitech (UK) 1PM52 type, polytex polishing pad, 4cm X 4cm square wafer (Wafer), grinding Zhuangli 4psi, grinding table speed 70rev/min, grinding head rotation speed 150rev/min, Polishing droplet acceleration is 100 ml/min.
- Comparative Example 1 shows that the polishing speed of tungsten is low only in the presence of hydrogen peroxide (hydrogen peroxide). Comparative Example 2 shows that: in combination with hydrogen peroxide (hydrogen peroxide) and silver ions, the polishing speed of tungsten is very low.
- Comparative Example 3 shows that: in combination with hydrogen peroxide (hydrogen peroxide) and manganese ions, the polishing speed of tungsten is very low.
- Comparative Example 4 shows that: In combination of silver ions and manganese ions, the polishing speed of tungsten is very low. Examples 1 to 4 show that: when hydrogen peroxide (hydrogen peroxide), silver ions and manganese ions are present at the same time, the polishing speed of tungsten is remarkably increased. Effect Example 2
- Polishing conditions 8 inch wafer, IC1000 polishing pad, pressure 4 psi.
- the data in Table 2 is the tungsten polishing rate of the chemical mechanical polishing liquid of Examples 5, 6 on the industrial machine of the present invention.
- the results show that the chemical mechanical polishing liquid of the present invention can achieve a very high polishing speed on an industrial machine. Effect Example 3
- Example 6 The chemical mechanical polishing liquid of Example 6 and the decomposition rate of the conventional Fe-H 2 2 chemical mechanical polishing liquid ⁇ hydrogen peroxide were tested, and the results are shown in FIG. 4 .
- hydrogen peroxide is very stable in the body of the present invention. The hydrogen peroxide concentration did not decrease within 29 days.
- U.S. Patent 5,958,288 uses iron nitrate as a catalyst, and hydrogen peroxide rapidly decomposes rapidly.
- U.S. Patent No. 5,980,775, 6,068,787 C conventional Fe-H 2 O 2 chemical mechanical polishing liquid, based on 5958288, adding an organic acid as a stabilizer to reduce the decomposition rate of hydrogen peroxide. However, it will still be reduced by 10% within 14 days.
- the formulation of the present invention has a significant improvement in stability. Comparative Example 1
- Table 4 shows the formulation of Comparative Example 5 ⁇ 18.
- the chemical mechanical polishing liquid can be prepared by mixing in deionized water. Polishing conditions: Polishing machine is Logitech (UK) 1PM52 type, polytex polishing pad, 4cm X 4cm square wafer (Wafer), grinding pressure 4psi, grinding table rotation speed 70rev/min, grinding head rotation speed 150rev/min, polishing The droplet acceleration is 100 ml/min. Table 4 Comparative chemical mechanical polishing solution of 5 to 18
- Table 4 lists representative transition metal elements "other than silver and iron.” From the results in Table 4, it can be seen that the effect of the present invention (achieving a high calendering rate of tungsten), which is not a single composition of a metal and a hydrogen peroxide, is achieved, and these single transition metal elements The combination with hydrogen peroxide does not significantly increase the polishing speed of tungsten.
- Table 5 shows the formulations of Comparative Examples 19 to 23, which are uniformly mixed in deionized water according to the components listed in Table 5 and their contents, to prepare a chemical mechanical polishing liquid.
- Polishing conditions Polishing machine is Logitech (UK) 1PM52 type, polytex polishing pad, 4cm X 4cm square wafer (Wafer), grinding pressure 4psi, grinding table speed 70rev/min, grinding The head rotation speed is 150 rpm, and the polishing droplet acceleration is 100 ml/min.
- Polishing machine is Logitech (UK) 1PM52 type, polytex polishing pad, 4cm X 4cm square wafer (Wafer), grinding pressure 4psi, grinding table speed 70rev/min, grinding The head rotation speed is 150 rpm, and the polishing droplet acceleration is 100 ml/min.
- Table 5 Chemical mechanical polishing solution of Comparative Example 19 ⁇ 23
- the effect of the present invention (achieving a high tungsten polishing rate) can be achieved without a combination of any two transition metals and hydrogen peroxide. Therefore, the present invention is "not obvious”. Moreover, the combination of two metal ions, Ag and Mn, and hydrogen peroxide, produces unexpected beneficial technical effects.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- Mechanical Treatment Of Semiconductor (AREA)
Description
-种用于钨化学机械抛光方法
技术领域
本发明涉及一种用于钨化学机械抛光方法,具体涉及用一种含有激发剂 的化学; ί光液对钨进行化学机械抛光的方法。 技术背景
随着半导体技术的不断发展, 以及大规模集成电路互连层的不断增加, 导电层和绝缘介质层的平坦化技术变得尤为关键。二十世纪 80年代,由 IBM 公司首创的化学机 tt^抛光(CMP)技术被认为是目前全局平坦化的最有效的 方法。
化学机械抛光(CMP)由化学作用、机械作用以及这两种作用结合而成。 它通常由一个带有抛光垫的研磨台, 及一个用于承载芯片的研磨头组成。其 中研磨头固定住芯片, 然后将芯片的正面压在抛光垫上。 当进行化学机械抛 光时, 研磨头在抛光垫上线性移动或是沿着与研磨台一样的运动方向旋转。 与此同时, 含有研磨剂的浆液被滴到抛光垫上, 并因离心作用平铺在抛光垫 上。 芯片表面在机械和化学的双重作用下实现全局平坦化。
对金属层化学机械抛光(CMP)的主要机制被认为是: 氧化剂先将金属 表面氧化成膜, 以二氧化硅和氧化铝为代表的研磨剂将该层氧化膜机械去 除, 产生新的金属表面继续被氧化, 这两种作用协同进行。
作为化学机 抛光(CMP)对象之一的金属钨, 在高电流密度下, 抗电 子迁移能力强, 并且能够与硅形成很好的欧姆接触, 所以可作为接触窗及介 层洞的填充金属及扩散阻挡层。
针对钨化学机械抛光 (CMP), 迄今为止, 主要利用两种方法: 氧化剂
直接氧化法 (例如: US5340370 , US5527423 , US6008119 , US6284151 , US5225034 , US5354490 ) , 催化法 (例如 US5958288 , US5980775 , 和 US6068787)。
氧化剂直接氧化法:
1991年, F. B. Kaufman等报道了铁氰化钾用于钨化学机械抛光的方法 ( "Chemical Mechanical Polishing for Fabricating Patterned W Metal Features as Chip Interconnects" , Journal of the Electro chemical Society, Vol.138, No.11 , 1991年 11月)。
美国专利 5340370公开了一种用于钨化学机械抛光(CMP)的配方, 其 中含有 0.1M铁氰化钾, 5%氧化硅, 同时含有作为 pH缓冲剂的醋酸盐。 由 于铁氰化钾在紫外光或日光照射下, 以及在酸性介质中, 会分解出剧毒的氢 氰酸, 因而限制了其广泛使用。
美国专利 5527423, 美国专利 6008119, 美国专利 6284151等公开了将 Fe (N03 ) 3, 氧化铝体系用于钨机械抛光(CMP)的方法。 该抛光体系在静 态腐蚀速率 (static etch rate) 方面具有优势, 但是由于采用氧化铝作为研磨 剂, 产品缺陷 (defect) 方面存在显著不足。 同时高浓度的硝酸铁使得抛光 液的 pH值呈强酸性, 严重腐蚀设备, 同时, 生成铁锈, 污染抛光垫。 除此 之外, 高浓度的铁离子作为可移动的金属离子, 严重降低了半导体元器件的 可靠性。
美国专利 5225034, 美国专利 5354490公开了将过氧化氢和硝酸银共同 使用, 用做氧化剂进行金属的抛光方法。但是在该类型方法中, 硝酸银用量 很大(大于 2%), 造成抛光液成本过高, 研磨剂不稳定、 容易沉淀, 双氧水
快速分解等问题。
催化法:
美国专利 5958288公开了将硝酸铁用做催化剂, 过氧化氢用做氧化剂, 进行钨化学机械抛光的方法。 需要注意的是: 在该专利中, 提到了多种过渡 金属元素, 被实验证实显著有效的只有铁元素。 因此该发明的实际实施效果 和范围很有限。 该方法虽然大幅度降低了硝酸铁的用量, 但是由于铁离子仍 然存在, 和双氧水之间发生 Fenton反应, 双氧水会迅速、并且剧烈地分解失 效, 因此该抛光液存在稳定性差的问题。
美国专利 5980775和美国专利 6068787在美国专利 5958288基础上,加 入有机酸做稳定剂, 改善了过氧化氢的分解速率。 但是由于有机酸的引入, 使得抛光液 pH值较低 (通常低于 2.7左右), 造成设备腐蚀。 此外, 含有硝 酸铁的抛光液, pH值调节范围很窄。 因为当 pH值高于 2.7时, 硝酸铁会水 解, 生成氢氧化铁沉淀, 造成抛光液失效, 限制了其 pH值调节能力。 在环 保上, 由于有机酸的加入, 提高了抛光废液中有机物含量 (COD), 不利于 环保。 此外, 氧化剂 ¾ (氧水的稳定性问题仍然存在。 虽然加入有机酸做为稳 定剂, 改善了双氧水的分解速率, 但是其分解速率仍然较高, 通常两周内双 氧水浓度会降低 10%以上, 造成抛光速度下降, 抛光液逐渐分解失效。
中国专利 CN1966594A公开了一种在上述催化体系中加入 etch抑制剂的 方法, 但是由于其所用催化剂仍然是铁元素, 双氧水易分解、 稳定性差等问 题仍然存在。
以上文献和专利主要利用两种方法进行钨的化学机械抛光:氧化剂直接 氧化法和催化法。
本发明提供的钨的化学机械抛光方法是一种利用 "激发态" 的方法。 本发明和直接氧化法以及催化法的主要区别在于:
本发明至少涉及两步反应: 第一步, 激发剂开始激发氧化剂前体
(precursor); 第二步 , 被激发的氧化剂去氧化钨。 而直接氧化法以及催化 法只是一步反应。本发明至少涉及 3种化学组分: 过氧化物(A)、 强氧化剂 的前体(金属 B), 以及激发剂中的金属 C, 3种化学组分自身, 以及它们之 间的任意两两组合: A+B, A+C, B+C都不会对钨的抛光速度有显著的提升 效果, 只有三者同时存在时 (A+B+C), 才会产生意想不到的效果。
这一抛光过程和 US5958288, US5980775和 US6068787公开的 Fe-H202 抛光体系 (图 3 ) 存在显著不同:
在 Fe-H202抛光体系中,只存在一种金属,三价铁离子氧化钨的表面后, 自身被还原成二价铁离子, 二价铁离子被过氧化氢氧化成三价铁, 形成一催 化循环过程。 而在本专利所述的激发体系中, 必须存在两种金属, 任何单一 的金属 (无论是 Ag还是 Mn) 和过氧化氢单独作用, 都不会产生提升钨抛 光速度的效果。 只有当 Ag和 Mn两种金属结合在一起时,:才会产生意想不 到的效果。
在 Fe-H202抛光体系中, 铁会和过氧化氢之间产生 Fenton反应, 产生强 氧化性的羟自由基,有利于提高钨的抛光速度。而在本文所述的激发体系中, 没有 Fenton反应。
在 Fe-H202抛光体系中, 由于铁会和过氧化氢之间产生 Fenton反应, 过 氧化氢会迅速分解, 因此必须加入有机络合剂络合铁离子, 抑制这一分解过 程。而在本文所述的激发体系中, 由于没有 Fenton反应, 不加稳定剂, 过氧
化氢也保持非常稳定 发明概要
本发明解决的技术问题是用激发剂将强氧化剂的前体(precursor)激发, 从而显著提高了钨的化学机械抛光速度。
本发明的用于钨化学机械抛光方法为用一种含有激发剂的化学机械抛 光液对钨进行化学机械抛光, 所述化学机械抛光液还含有强氧化剂前体 ( precursor ) o
本发明中, 所述化学机械抛光液还含有水和研磨剂。所述的研磨剂选自 气相二氧化硅、硅溶胶、氧化铝和 /或氧化铈中的一种或多种。所述的研磨剂 的质量百分含量为 0.1〜20%。
本发明中, 所述的强氧化剂前体 (precursor) 为过渡金属化合物。 所述 的过渡金属化合物为二价锰化合物。所述的二价锰化合物为有机和 /或无机锰 盐。所述的无机锰盐为硝酸锰和 /或硫酸锰。所述的强氧化剂前体(precursor) 的质量百分含量为 0.05〜1 %。
本发明中,所述的激发剂为由非铁过渡元素金属盐和过氧化物组成的组 合物。所述的过氧化物为过硫酸铵、单过硫酸钾和 /或过氧化氢中的一种或多 种。 述的过氧化物的质量百分含量为 0.1〜10%。 所述的非铁过渡元素金属 盐为银盐。 所述的银盐为硝酸银。 所述的银盐的质量百分含量为 0.05〜2%。
本发明中, 所述化学机械抛光液还含有 pH调节剂, 所述的 pH调节剂 为无机或有机酸、 无机或有机碱。 所述化学机械抛光液的 pH值为 0.5~4.5。
所述化学机械抛光液还含有含有静态腐蚀速度(static etch rate)抑制剂。
所述的静态腐蚀速度 (static etch rate) 抑制剂为有机膦化合物。 所述的有机 膦化合物为乙二胺四甲叉膦酸 (EDTMP) 。 本发明中的激发是指: 该氧化剂在 "被激发"之前, 不具有强氧化性, 但是在 "被激发"之后, 能够表现出非常强的氧化能力 (抛光速度); 该氧 化剂在 "被激发"前后, 化学价态并没有改变。 本发明所用的配方从功能上划分, 至少含有以下两部分: 强氧化剂的前 体 (precursor) 以及激发剂。 强氧化剂的前体是一种可溶性的低价态的金属离子, 该低价态的金属离 子自身氧化性较弱, 但是其在高价态时, 可以表现出非常强的氧化性。 例如 二价锰离子, 其标准电极电位为 -1.029 (V) , 氧化能力非常弱,
Mn2+ + 2 ^ = Mn (s) , E。= - 1.029 (V)
而 7价的锰, 例如高锰酸钾则是一强氧化剂。 激发剂可以由两种或两种及以上的组分共同组成。其共同作用的结果是 将 "强氧化剂的前体"激发。 发剂的具体组成, 包括: 氧化剂 +过渡金属。 本发明中典型的激发剂为 "过氧化氢 +银离子"。过氧化氢在银离子的作 用下可以将 "强氧化剂的前体"(例如: 二价锰离子) "激发", 达到 "激发 态"。 但是, 在没有接触到被抛光的物质 (诸如钨)之前, 过氧化氢、 银离 子、 "强氧化剂的前体"三者之间, 并没 真正发生化学反应, 化学价态保 持不变, 抛光液各组分之间都保持在非常稳定的状态。
"过氧化氢 +银离子" 的特殊激发性能, 需要结合 "不同的过氧化物和 银离子相互作用"而产生的不同机理来解释。 以下结构式是常见的三种过氧 化物。 它们的共同特点是: 都含有过氧键 -0-0-。
过氧化氢 过氧键上取代基的不同, 会导致和银离子作用的效果不同。 例如: 在测 定二价锰离子含量时, 过硫酸铵在银离子的存在下, 可以将二价锰迅速氧化 成 7价高锰酸根, 显紫色, 然后采用分光光度法测定含量。
在室温、银离子存在下,单过硫酸钾将二价锰氧化成 7价锰的反应过程, 和前面介绍的过硫酸铵相比, 反应非常缓慢, 但是反应仍然可以进行。
作为对比, 过氧化氢在银离子存在下, 不能将二价锰氧化成 7价猛, 只 能将锰离子 "激发"至激发态。
同是过氧化物, 它们之间表现不同。这一渐变的过程可以进一步地通过 "能垒"来说明, 如图 1所示, 若将二价锰氧化成 7价锰, 需要经过一能垒 (曲线 1), 过硫酸铵在银离子的存在下 ¾1以轻易越过这一能垒 (曲线 111), 单过硫酸钾的反应速度较慢 (曲线 11), 但是反应^ 5然可以进行。 过氧化氢 在银离子的作用下, 不足以越过这一能垒, 反应不能进行, 但是二价锰离子 被激发, 处于激发状态 (Mn"。
本发明中激发态的锰离子接触到被抛光材料(钨)时, 表现出非常强的 氧化能力 (抛光速度)。 这一抛光过程如图 2所示; 传统的 Fe-H202抛光体 系的抛光过程如图 3所示。 在过氧化氢的作用下, 一价银离子被氧化成 "过 渡态"的 Ag*, 该 "过渡态 "的 Ag*将二价锰氧化成激发态的 Mn*, 该激发 态的 Mn*接触到钨表面时, 表现出强氧化性, 将钨氧化成二氧化钨和三氧化
钨,在研磨剂的机械作用下,钨的氧化物被去除。从而实现连续不断的抛光。 这一抛光过程和 (图 3 ) 的 Fe-H202抛光体系存在显著不同:
在 Fe-H202抛光体系中, 依赖铁离子一种金属实现催化循环过程。 而在 本发明所述的激发体系中, 必须存在两种金属, 任何单一的金属 (无论是 Ag还是 Mn)和过氧化氢单独作用, 都不会产生提升钨抛光速度的效果。 只 有当 Ag和 Mn两种金属结合在一起时, 才会产生意想不到的效果。 并且这 种抛光成分的组合并非显而易见的。 我们在研究中发现, 只有极少量的单一 金属对双氧水存在催化作用, 效果最显著的是铁离子。 同时, 我们还进一步 研究了两种及两种以上不同的过渡金属和双氧水的组合,发现大多数过渡金 属的两两组合, 以及多个组合, 对双氧水都没有催化作用, 只有当 Ag 和 Mn两种金属离子结合在一起时, 才会产生意想不到的效果。
本发明的积极进步效果在于:
.1、 将强氧化剂的前体 (precursor) 进行激发, 然后用于化学机械抛光, 显著提高了钨的抛光速度, 提高了生产效率 降低制造成本。
2、 在不加入过氧化氢稳定剂的情况下, 所述的方法中, 过氧化氢仍能 非常稳定地存在于抛光液中。解决了过氧化氢快速分解的问题, 延长了抛光 液的使用时限, 保证了抛光速度的稳定, 从而进一步节约成本。
3、 本发明的的化学机械抛光方法, 可以不含^ "机物 (稳定剂, 诸如有 机酸等) 。 因此, 降低了抛光废液中有机物的含量 (COD排放量) , 有利 于环保。
4、 本发明的的化学机械抛光方法中, 使用的化学机械抛光液具有更宽 的 pH调节范围, 可以通过升高 pH值来降低对设备的腐蚀, 应用于更广的
CMP领域。
附图说明 图 1 ¾:硫酸铵, 单过硫酸钾和过氧化氢的 "能垒"示意图。 图 2 本发明化学机械抛光液的抛光示意图。 图 3传统的 Fe-H202抛光体系的抛光示意图。 图 4 实施例 6和传统 Fe-H202的化学机械抛光液中过氧化氢的分解速度 示意图。
发明内容
制备实施例
表 1给出了本发明的化学机械抛光液实施例 1~16及对比例 1~4的配方, 按表 1中所列组分及其含量, 在去离子水中混合均匀, 用 pH调节剂调到所 需 pH值,:即可制得化学机械抛光液。 : 表 1本发明的化学机械抛光液实施例 1~16及对比例 1~4
研磨剂 氧化剂 过渡金属 :
pH调节 含 含 ■ ^属 *卜 含 抑制剂 PH 名称 含量 金属盐 1 量 剂
wt% 名称 量 2 量
wt% wt% wt%
对比例 1 气相二氧 1.3 过氧化 5 . 稀硝酸 2.5
化硅 氢
对比例 2 气相二氧 1.3 过氧化 , 5 ί肖酸银 0,2 稀硝酸 2.5
化硅 氢.
对比例 3 气相二氧 1.3 过氧化 5 硝酸锰 0.5 稀硝酸 2.5
化硅 氢 .
对比例 4 气相二氧 1.3 硝酸银 0.2 硝酸锰 0.5 稀硝酸 2.5
化硅
气相二氧
实施例 1 1.3 过氧化 5 硝酸银 0.2 硫 猛 0.5 稀硝酸 2.5
化硅 氢
实施例 2 气相二氧 1.3 过氧化 5 硝酸银 0.2 硝酸锰 0.25 稀硝酸 2.5
化硅 氢
气相二氧 化
实施例 3 1.3 过氧 5 硝酸银 0.05 硫酸锰 0.5
化硅 稀硝酸 2.5
氢
气相二氧 过氧化
实施例 4 1.3 5 硝酸银 0.1 硝酸锰 0.5 稀硝酸 2.5
化硅 氢
实施例 5 气相二氧 1.3 氧化 1 硝酸银 0.2 硫酸锰 0.5 稀硝酸 2.5 化硅 氢
实施例 6 气相二氧 1.3 过氧化 2 硝酸银 0.2 硫酸锰 0.5 稀硝酸 2.5 化硅 氢
气相二氧
实施例 Ί 1.3 过氧化 5 硝酸银 0.1 硫酸锰 1 稀硝酸 2.5 化硅 氢
气相二氧
实施例 8 1.3 过氧化 5 硝酸银 0.5 硝酸锰 0.05 稀硝酸 2.5 化硅 . 氢
气相二氧 20 过氧化
实施例 9 1 硝酸银 0.2 硫酸锰 0.5
化硅 稀硝酸 3.5 氢
实施例 7 硅溶胶 0.5 过氧化 10 硝酸银 1 硫酸锰 0.25 稀硝酸 0.5 氢
实施例 10 硅溶胶 10 过氧化 1 硝酸银 2 硝酸锰 0.25 氢氧化钾 4.5 氢
实施例 1 1 硅溶胶 0.1 0.1 柠檬酸 0.1 硫酸锰 0.25
氢 银 稀硝酸 1 实施例 12 氧化铝 2 过氧化 5 硝酸银 0.1 硫酸锰 2 稀硝酸 3 氢
实施例 13 氧化铈 2 过氧化 8 硝酸银 0.1 硫酸锰 0.5 稀硝酸 3.5 氢
实施例 14 气相二氧 1.3 过氧化 2 硝酸银 0.2 硫酸锰 0.5 EDTMP
2.5 化硅 氢 50 ppm 稀硝酸
二氧 EDTMP 实施例 15 气相 1.3 过氧化 2 : 硝酸银 0.2 硫酸锰 0.5 100 稀硝酸 2.5 化硅 氢 PPm
EDTMP
。实施例 16 气相二氧 1.3 过氧化 2 硝酸银 0.2 硫酸锰 0.5 500 2.5 化硅 稀硝酸
氢 ppm 效果实施例 1
抛光条件:抛光机台为 Logitech (英国) 1PM52型, polytex抛光垫, 4cm X 4cm正方形晶圆 (Wafer), 研磨庄力 4psi, 研磨台转速 70转 /分钟, 研磨 头自转转速 150转 /分钟, 抛光液滴加速度 100 ml/分钟。 表 2用于钨抛光的实施例 〜 4及对比例 1〜4 钨抛光速率 (A/min) 对比例 1 121
对比例 2 178
对比例 3 52
对比例 4 136
实施例 1 3100
实施例 2 2980
实施例 3 2010
实施例 4 2230
对比例 1表明: 只有过氧化氢(过氧化氢)存在时, 钨的抛光速度很低。 对比例 2表明: 过氧化氢(过氧化氢)和银离子组合, 钨的抛光速度很 低。
对比例 3表明: 过氧化氢 (过氧化氢)和锰离子组合, 钨的抛光速度很 低。 . . 对比例 4表明: 银离子和锰离子组合, 钨的抛光速度很低。 实施例 1〜4表明: 过氧化氢 (过氧化氢)、 银离子和锰离子三者同时存 在时., 钨抛光速度显著升高。 效果实施例 2
,抛光条件: 8 inch wafer, IC1000抛光垫, 压力 4psi。
表 2用于钨抛光的实施例 5~6及对比例 1~4
静态腐蚀速率测试: 将 wafer在室温下, 浸泡于抛光液中 30分钟测得。 表 3用于钨抛光的实施例 6及 14~16
静态腐蚀是造成钨栓塞 (Tungsten Plug)被腐蚀(etch), 以及造成穿孔 (key hole) 的主要原因。 从表 3中的结果可以看出, 在本发明中进一步加 入抑制剂可以显著改善静态腐蚀速率, 提升抛光产品的良率。 效果实施例 4
纷别对实施例 6的化学机械抛光液以及传统 Fe-H202化学机械抛光液 Φ 过氧化氢的分解速度进行测试,结果如图 4所示。 从图 4中可以看出, 在本 发明的体¾中, 过氧化氢会非常稳定。 过氧化氢浓度在 29天内不降低。 而 作为对比, 美国专利 5958288用硝酸铁做催化剂, 过氧化氢会迅速剧烈分解 失效。美国专利 5980775 , 6068787C传统 Fe-H202化学机械抛光液)在 5958288 基础上, 加入有机酸做稳定剂, 降低了过氧化氢的分解速率。 但是 14天内 仍会降低 10%。 本发明的配方在稳定性上有显著进歩。 对比实施例 1
表 4给出了对比例 5~18的配方, 按表 4中所列组分及其含量, 在去离 子水中混合均勾, 即可制得化学机械抛光液。
抛光条件:抛光机台为 Logitech (英国) 1PM52型, polytex抛光垫, 4cm X 4cm正方形晶圆 (Wafer), 研磨压力 4psi, 研磨台转速 70转 /分钟, 研磨 头自转转速 150转 /分钟, 抛光液滴加速度 100 ml/分钟。 表 4对比例 5〜18的化学机械抛光液
表 4列出了 "除了银和铁之外"的代表性的过渡金属元素。 从表 4中的 结果^ "以看出, 不是任意单一的^:渡金属和双氧水的组令, 就能够实现本发 明的效果 (实现钨很高的 έ光速率), 这些单一的过渡金属元素和过氧化氢 的组合不能显著提高钨的抛光速度。
对比实施例 2
表 5给出了对比例 19~23的配方, 按表 5中所列组分及其含量, 在去离 子水中混合均匀, 即可制得化学机械抛光液。 抛光条件:抛光机台为 Logitech (英国) 1PM52型, polytex抛光垫, 4cm X 4cm正方形晶圆 (Wafer) , 研磨压力 4psi, 研磨台转速 70转 /分钟, 研磨
头自转转速 150转 /分钟, 抛光液滴加速度 100 ml/分钟。 表 5对比例 19~23的化学机械抛光液
Claims
权利要求 、 一种用于钨化学机械抛光方法, 其特征在于: 用一种含有激发剂的化学 机械抛光液对钨进行化学机械抛光, 所述化学机械抛光液还含有强氧化 剂前体 ( precursor )o
、 根据权利要求 1 所述的化学机械抛光方法, 所述化学机械抛光液还含有 水和研磨剂。
、 根据权利要求 2所述的化学机械抛光方法, 所述的研磨剂选自气相二氧 化硅、 硅溶胶、 氧化铝和 /或氧化铈中的一种或多种。
、 根据权利要求 2所述的化学机械抛光方法, 所述的研磨剂的质量百分含 量为 0.:!〜 20%。
、 根据权利要求 1 或 2 所述的化学机械抛光方法, 所述的强氧化剂前体
(precursor) 为过渡金属化合物。
、 根据权利要求 5所述的化学机械抛光方法, 所述的过渡金属化^ ·物为二 价锰化合物。
、 根据权利要求 6所述的化学机械抛光方法, 所述的二价猛化合物为有机 和 /或无机锰盐。
、 根据权利要求 7所述的化学机械抛光方法, 所述的无机锰盐为硝酸锰和 / 或硫酸猛。
、 根据权利要求 1 或 2 所述的化学机械抛光方法, 所述的强氧化剂前体
(precursor) 的质量百分含量为 0.05~1 %。
0、 根据权利要求 1或 2所述的化学机械抛光方法, 所述的激发剂为由非铁 过渡元素金属盐和过氧化物组成的组合物。
、 根据权利要求 10所述的化学机械抛光方法, 所述的过氧化物为过硫酸 铵、 单过硫酸钾和 /或过氧化氢中的一种或多种。
、 根据权利要求 10所述的化学机械抛光方法, 所述的过氧化物的质量百 分含量为 0.卜 10%。
、 根据权利要求 10所述的化学机械抛光方法, 所述的非铁过渡元素金属 盐为银盐。
、 根据权利要求 13所述的化学机械抛光方法, 所述的银盐为硝酸银。 、 根据权利要求 13所述的化学机械抛光方法, 所述的银盐的质量百分含 量为 0.05〜2%。
、 根据权利要求 1或 2所述的化学机械抛光方法, 所述^ ^学机械抛光液还 含有 pH调节剂, 所述的 pH调节剂为无机或有机酸、 无机或有机碱。 、 根据权利要求 16所述的化学机械抛光方法, pH值为 0.5〜4.5。
、根据权利要求 1或 2所述的化学机械抛光方法, 所述化学机械抛光液还 含有含有静态腐蚀速度 (static etch rate) 抑制剂。
、根据权利要求 18所述的化学机械抛光方法,所述的静态腐蚀速度(static etch rate) 抑制剂为有机膦化合物。
、 根据权利要求 19所述的化学机械抛光方法, 所述的有机膦化合物为乙 二胺四甲叉膦酸 (EDTMP)。
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201010109918.1 | 2010-02-11 | ||
CN201010109918 | 2010-02-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2011097954A1 true WO2011097954A1 (zh) | 2011-08-18 |
Family
ID=44367238
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/CN2011/000205 WO2011097954A1 (zh) | 2010-02-11 | 2011-02-09 | 一种用于钨化学机械抛光方法 |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2011097954A1 (zh) |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5354490A (en) * | 1992-06-04 | 1994-10-11 | Micron Technology, Inc. | Slurries for chemical mechanically polishing copper containing metal layers |
CN1622985A (zh) * | 2002-01-24 | 2005-06-01 | Cmp罗姆和哈斯电子材料控股公司 | 钨抛光溶液 |
CN1854234A (zh) * | 2005-04-21 | 2006-11-01 | 安集微电子(上海)有限公司 | 抛光浆料及其用途和使用方法 |
CN101313042A (zh) * | 2005-09-26 | 2008-11-26 | 卡伯特微电子公司 | 用于钽的化学机械抛光的组合物及方法 |
WO2008142093A1 (en) * | 2007-05-24 | 2008-11-27 | Basf Se | Chemical-mechanical polishing composition comprising metal-organic framework materials |
CN101316950A (zh) * | 2005-09-29 | 2008-12-03 | 卡伯特微电子公司 | 增加含过氧化氢的化学机械抛光浆料使用寿命的组合物及方法 |
-
2011
- 2011-02-09 WO PCT/CN2011/000205 patent/WO2011097954A1/zh active Application Filing
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5354490A (en) * | 1992-06-04 | 1994-10-11 | Micron Technology, Inc. | Slurries for chemical mechanically polishing copper containing metal layers |
CN1622985A (zh) * | 2002-01-24 | 2005-06-01 | Cmp罗姆和哈斯电子材料控股公司 | 钨抛光溶液 |
CN1854234A (zh) * | 2005-04-21 | 2006-11-01 | 安集微电子(上海)有限公司 | 抛光浆料及其用途和使用方法 |
CN101313042A (zh) * | 2005-09-26 | 2008-11-26 | 卡伯特微电子公司 | 用于钽的化学机械抛光的组合物及方法 |
CN101316950A (zh) * | 2005-09-29 | 2008-12-03 | 卡伯特微电子公司 | 增加含过氧化氢的化学机械抛光浆料使用寿命的组合物及方法 |
WO2008142093A1 (en) * | 2007-05-24 | 2008-11-27 | Basf Se | Chemical-mechanical polishing composition comprising metal-organic framework materials |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
TWI577788B (zh) | 用於降低腐蝕的化學機械拋光漿料及其使用方法 | |
KR102320653B1 (ko) | 감소된 산화물 침식을 위한 텅스텐 화학적 기계적 연마 슬러리 | |
US7014669B2 (en) | Catalytic composition for chemical-mechanical polishing, method of using same, and substrate treated with same | |
JP5571649B2 (ja) | タングステンの蝕刻抑制剤を含むポリシング組成物 | |
EP3604468B1 (en) | Tungsten chemical mechanical planarization (cmp) with low dishing and low erosion topography | |
WO2007050409A1 (en) | Polishing fluids and methods for cmp | |
JPH10265766A (ja) | 金属のcmpに有用な組成物及びスラリー | |
JP2004532509A (ja) | 固体触媒を含むcmp研磨パッド | |
CN102051129B (zh) | 一种化学机械抛光液 | |
WO2012088756A1 (zh) | 一种抛光钨的化学机械抛光液 | |
WO2012068775A1 (zh) | 一种化学机械抛光液 | |
WO2012019425A1 (zh) | 一种化学机械抛光液 | |
WO2011097954A1 (zh) | 一种用于钨化学机械抛光方法 | |
WO2012009959A1 (zh) | 一种化学机械抛光液 | |
TWI838447B (zh) | 用於拋光鎢的化學機械拋光液 | |
TWI431082B (zh) | Chemical mechanical polishing solution | |
WO2012055153A1 (zh) | 一种钨化学机械抛光方法 | |
TWI431083B (zh) | Chemical mechanical polishing solution | |
WO2011054193A1 (zh) | 一种化学机械抛光液 | |
WO2012016424A1 (zh) | 一种化学机械抛光液 | |
CN116285696A (zh) | 一种用于钨及其合金高效抛光的化学机械抛光液 | |
CN117403233A (zh) | 一种高速率的钨插塞化学机械抛光液及其应用 | |
TW201226493A (en) | Chemical mechanical polishing slurry for polishing tungsten |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11741825 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 11741825 Country of ref document: EP Kind code of ref document: A1 |