# US 12,603,254 B2 · Etching method and plasma processing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,603,254 B2 - Document ID: US12603254B2 - Status: Granted - Kind: B2 - Application number: 18/380,066 - Filed: 2023-10-13 - Published: 2024-02-01 - Granted: 2026-04-14 - Earliest claimed: 2021-04-14 - Assignees: Tokyo Electron Limited - Applicants: Tokyo Electron Limited - Inventors: Akira Nakagawa; Kenji Komatsu; Kazuma Kamimura; Tsukasa Hirayama - Web page: https://patentgrep.com/patent/US12603254B2 ## CPC - H01J 37/32449: {Gas control, e.g. control of the gas flow} - H01J 37/32357: {Generation remote from the workpiece, e.g. down-stream} - H10P 50/242: {of Group IV materials} - H10P 50/268: {of silicon-containing layers} - H10P 50/283: {by chemical means} - H10P 72/0421: {for drying etching} - H10P 72/72: using electrostatic chucks - H01J 2237/334: Etching - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract A substrate etching method performed by using a plasma processing apparatus includes: providing a substrate including a silicon-containing film to a substrate support; periodically supplying, to the substrate support, bias RF power of 20 KW to 50 kW at a duty ratio of 5% to 50%; and etching the silicon-containing film by plasma generated from a processing gas containing a fluorocarbon gas and an oxygen-containing gas. ## Claims ### Claim 1 An etching method comprising: (A) providing a substrate including a silicon-containing film on a substrate support; (B) periodically supplying, to the substrate support, bias RF power of 20 kW to 50 kW at a duty ratio of 5% to 50%; and (C) etching the silicon-containing film by plasma generated from a processing gas containing a fluorocarbon gas and an oxygen-containing gas. ### Claim 2 (depends on 1) The etching method according to claim 1, wherein the bias RF power is 23 kW to 40 KW. ### Claim 3 (depends on 1) The etching method according to claim 1, wherein the duty ratio of the bias RF power is 10% to 40%. ### Claim 4 (depends on 1) The etching method according to claim 1, wherein the silicon-containing film includes a first region having a multilayer film in which at least two of films selected from the group consisting of a silicon oxide film, a silicon nitride film, and a polysilicon film are stacked, and a second region having a single-layer film of a silicon oxide film. ### Claim 5 (depends on 4) The etching method according to claim 4, wherein (C) includes: (C1) etching the silicon-containing film by plasma generated from a first processing gas containing a fluorocarbon gas, a hydrofluorocarbon gas, and an oxygen-containing gas, in which a flow rate ratio of the fluorocarbon gas to the oxygen-containing gas is larger than 1.0; and (C2) etching the silicon-containing film by plasma generated from a second processing gas containing a fluorocarbon gas, a hydrofluorocarbon gas, and an oxygen-containing gas, in which a flow rate ratio of the fluorocarbon gas to the oxygen-containing gas is 1.0 or less. ### Claim 6 (depends on 5) The etching method according to claim 5, wherein a flow rate ratio of the fluorocarbon gas to the hydrofluorocarbon gas in the first processing gas is larger than a flow rate ratio of the fluorocarbon gas to the hydrofluorocarbon gas in the second processing gas. ### Claim 7 (depends on 5) The etching method according to claim 5, wherein a cycle including (C1) and (C2) is performed once or more. ### Claim 8 (depends on 5) The etching method according to claim 5, wherein a ratio of a processing time in (C2) to a processing time in (C1) is 2 to 3. ### Claim 9 (depends on 1) The etching method according to claim 1, wherein the silicon-containing film includes a first region having a multilayer film in which a silicon oxide film and a silicon nitride film are alternately stacked, and a second region having a single-layer film of a silicon oxide film. ### Claim 10 (depends on 1) The etching method according to claim 1, further comprising (D) applying a negative DC voltage to an upper electrode facing the substrate support. ### Claim 11 (depends on 10) The etching method according to claim 10, wherein (D) includes: (D1) applying a first voltage to the substrate support during a first period when the bias RF power or the electrical bias is supplied; and (D2) applying a second voltage having a different absolute value from the first voltage to the substrate support during a second period when the bias RF power or the electrical bias is not supplied. ### Claim 12 (depends on 11) The etching method according to claim 11, wherein the absolute value of the second voltage is larger than the absolute value of the first voltage. ### Claim 13 (depends on 12) The etching method according to claim 12, wherein the absolute value of the first voltage is 250 V to 500 V, and the absolute value of the second voltage is 1,000 V or more. ### Claim 14 (depends on 1) The etching method according to claim 1, wherein a patterned mask layer containing carbon or boron is provided on the silicon-containing film. ### Claim 15 An etching method comprising: (A) providing a substrate including a silicon-containing film on a substrate support; (B) supplying, to the substrate support, electrical bias of 7 kV to 20 kV at a duty ratio of 5% to 50%; and (C) etching the silicon-containing film by plasma generated from a processing gas containing a fluorocarbon gas and an oxygen-containing gas. ### Claim 16 (depends on 15) The etching method according to claim 15, wherein the duty ratio of the electrical bias is 10% to 40%.