# US 8,273,258 B2 · Fine pattern forming method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,273,258 B2 - Document ID: US8273258B2 - Status: Granted - Kind: B2 - Application number: 12/651,519 - Filed: 2010-01-04 - Published: 2010-07-08 - Granted: 2012-09-25 - Earliest claimed: 2009-01-07 - Assignees: Tokyo Electron Limited - Inventors: Takashi Sone; Eiichi Nishimura - Web page: https://patentgrep.com/patent/US8273258B2 ## CPC - H10P 76/204: {of organic photoresist masks} - G03F 7/0035: {Multiple processes, e.g. applying a further resist layer on an already in a previously step, processed pattern or textured surface} - G03F 7/40: Treatment after imagewise removal, e.g. baking - H10P 50/287: {by chemical means} - H10P 50/71: {using masks for conductive or resistive materials} - H10P 50/73: {using masks for insulating materials} - H10P 76/4088: {Processes for improving the resolution of the masks} - G03F 7/427: {using plasma means only} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract A disclosed fine pattern forming method includes steps of: forming patterns made of a first photoresist film, arranged at a first pitch on a film; trimming the patterns made of the first photoresist film; depositing a protection film on the patterns made of the first photoresist film on the trimmed patterns made of the first photoresist film, the protection film being made of reaction products of an etching gas, thereby obtaining first patterns; forming other patterns made of a second photoresist film, arranged at a second pitch, on the protection film, the other patterns made of the second photoresist film being shifted by half of the first pitch from the corresponding patterns made of the first photoresist film; trimming the other patterns made of the second photoresist film into second patterns; and etching the film using the first patterns and the second patterns. ## Claims ### Claim 1 A fine pattern forming method for patterning a film formed on a substrate, the fine pattern forming method comprising steps of: forming patterns made of a first photoresist film, arranged at a first pitch on the film; trimming the patterns made of the first photoresist film; depositing a protection film on trimmed patterns made of the first photoresist film, the protection film being made of reaction products of an etching gas, thereby obtaining first patterns; forming other patterns made of a second photoresist film, arranged at a second pitch, on the protection film, the other patterns made of the second photoresist film being shifted by half of the first pitch from the corresponding patterns made of the first photoresist film; trimming the other patterns made of the second photoresist film into second patterns; and etching the film using the first patterns and the second patterns, wherein the step of trimming the patterns made of the first photoresist film and the step of trimming the other patterns made of the second photoresist film are carried out using at least one of oxygen radicals and ozone gas, and wherein the protection film made of the reaction products of the etching gas is tolerant of the oxygen radicals and the ozone gas. ### Claim 2 (depends on 1) The fine pattern forming method of claim 1, wherein the patterns made of the first photoresist film are formed on a hard mask film that covers the substrate in the step of forming the patterns made of the first photoresist film; and wherein the hard mask film is etched using the first patterns and the second patterns, and the film is etched using the etched hard mask film in the step of etching the film. ### Claim 3 (depends on 1) The fine pattern forming method of claim 1, wherein the protection film is deposited in an etching apparatus by supplying an etching gas in the step of depositing the protection RIM. ### Claim 4 (depends on 3) The fine pattern forming method of claim 3, wherein the step of trimming the patterns made of the first photoresist film is carried out in the etching apparatus, and wherein the protection film is consecutively deposited in the etching apparatus in the step of depositing the protection film. ### Claim 5 (depends on 1) The fine pattern forming method of claim 1, wherein the patterns made of the first photoresist film are formed via an anti-reflection coating film in the step of forming the patterns made of the first photoresist film. ### Claim 6 (depends on 1) The fine pattern forming method of claim 1, wherein the first patterns having a predetermined line width are obtained by adjusting a trimming time in the step of trimming the patterns made of the first photoresist film and/or a deposition time in the step of depositing the protection film. ### Claim 7 (depends on 1) The fine pattern forming method of claim 1, wherein the film is at least one of silicon nitride, silicon oxide, amorphous silicon, and poly silicon. ### Claim 8 (depends on 5) The fine pattern forming method of claim 5, wherein the anti-reflection coating film is at least one of amorphous carbon, poly phenol, and photoresist. ### Claim 9 (depends on 1) The fine pattern forming method of claim 1, wherein the etching gas includes fluorocarbon. ### Claim 10 (depends on 1) The fine pattern forming method of claim 1, wherein the etching gas includes a halogen-containing gas. ### Claim 11 (depends on 9) The fine pattern forming method of claim 9, wherein the fluorocarbon is at least one of CH3F, CHF3, and CF4. ### Claim 12 (depends on 10) The fine pattern forming method of claim 10, wherein the halogen-containing gas is at least one of HBr and SF6. ### Claim 13 (depends on 1) The fine pattern forming method of claim 1, wherein the step of trimming the patterns made of the first photoresist film is carried out using at least one of an oxygen-containing gas plasma and ozone gas. ### Claim 14 (depends on 13) The fine pattern forming method of claim 13, wherein the oxygen-containing gas plasma is obtained by activating at least one of O2 gas, NO gas, N2O gas, H2O gas and O3 gas into plasma.