# US 12,112,939 B2 · Cleaning process and semiconductor processing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,112,939 B2 - Document ID: US12112939B2 - Status: Granted - Kind: B2 - Application number: 17/489,996 - Filed: 2021-09-30 - Published: 2022-08-04 - Granted: 2024-10-08 - Earliest claimed: 2021-02-03 - Assignees: Changxin Memory Technologies, Inc. - Applicants: Changxin Memory Technologies, Inc. - Inventors: Zhaopei Cui; Bingyu Zhu - Web page: https://patentgrep.com/patent/US12112939B2 ## CPC - H10P 70/20: {Cleaning during device manufacture} - H10P 70/27: {during, before or after processing of conductive materials, e.g. polysilicon or amorphous silicon layers} - B08B 7/00: Cleaning by methods not provided for in a single other subclass or a single group in this subclass - H10P 30/204: {into Group IV semiconductors} - H10P 30/21: {of electrically active species} - H10P 50/283: {by chemical means} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL ## Abstract A cleaning process for cleaning a surface of a semiconductor structure is provided, in which residue layer is formed on the surface of the semiconductor structure. The cleaning process includes providing a first reaction gas and a second reaction gas to the surface of the semiconductor structure, in which the first reaction gas reacts with the second reaction gas to remove the residue layer while forming a protection layer on the surface of the semiconductor structure. ## Claims ### Claim 1 A cleaning process, for cleaning a surface of a semiconductor structure, on which a residue layer is formed, wherein the cleaning process comprises: providing a first reaction gas and a second reaction gas to the surface of the semiconductor structure, wherein the first reaction gas reacts with the second reaction gas to remove the residue layer while forming a protection layer on the surface of the semiconductor structure; wherein the semiconductor structure comprises a doped polysilicon substrate or comprises a doped polysilicon layer, and the residue layer is located on a surface of the doped polysilicon substrate or a surface of the doped polysilicon layer; and wherein the residue layer comprises oxide particles, the first reaction gas reacts with the second reaction gas to generate ammonia gas and hydrogen fluoride, and the ammonia gas and hydrogen fluoride react with the residue layer to remove the residue layer. ### Claim 2 (depends on 1) The cleaning process of claim 1, wherein the first reaction gas comprises nitrogen trifluoride gas, the second reaction gas comprises a gas containing ammonium fluosilicate peroxide or a derivative formed of ammonium fluosilicate peroxide and an alkane, wherein a compound of the second reaction gas is represented by the general formula below: wherein X is —(CH2)n—, n is an integer greater than or equal to 1. ### Claim 3 (depends on 2) The cleaning process of claim 2, wherein the alkane is represented by CnH2n+2, wherein n is an integer greater than or equal to 1. ### Claim 4 (depends on 2) The cleaning process of claim 2, wherein a reaction temperature for the reaction of the first reaction gas and the second reaction gas is 300° C. to 400° C. ### Claim 5 (depends on 2) The cleaning process of claim 2, wherein a chemical reaction equation of the nitrogen trifluoride gas and the ammonium fluosilicate peroxide gas is: SiO2+6HF+2NH3→(NH4)2SiF6+2H2O; wherein NH3, HF and F2O are gaseous, and Si is solid polysilicon. ### Claim 6 (depends on 5) The cleaning process of claim 5, wherein the oxide particles comprise silicon dioxide particles; a reaction chemical formula of the ammonia gas, the hydrogen fluoride and the silicon dioxide particles is: SiO2+6HF+2NH3→(NH4)2SiF6+2H2O (NH4)2SiF6→(NH4)2SiF6↑ wherein (NH4)2SiF6 generated by the reaction of the ammonia gas, hydrogen fluoride and the silicon dioxide particles is solid, and solid (NH4)2SiF6 is sublimated into gaseous (NH4)2SiF6. ### Claim 7 (depends on 1) The cleaning process of claim 1, wherein the first reaction gas reacts with the second reaction gas under a non-plasma condition. ### Claim 8 (depends on 1) A semiconductor processing method, comprising cleaning the semiconductor structure with the cleaning process of claim 1. ### Claim 9 (depends on 8) The semiconductor processing method of claim 8, further comprising performing ion implantation on a polysilicon substrate or a polysilicon layer to form the semiconductor structure before cleaning the semiconductor structure. ### Claim 10 (depends on 9) The semiconductor processing method of claim 9, further comprising forming a deposition material layer on the surface of the semiconductor structure after cleaning the semiconductor structure. ### Claim 11 (depends on 8) The semiconductor processing method of claim 8, wherein the semiconductor processing method is used for preparation of a memory device. ### Claim 12 (depends on 11) The semiconductor processing method of claim 11, wherein the memory device comprises a flash memory or a dynamic random access memory. ### Claim 13 A cleaning process, for cleaning a surface of a semiconductor structure, on which a residue layer is formed, wherein the cleaning process comprises: providing a first reaction gas and a second reaction gas to the surface of the semiconductor structure, wherein the first reaction gas reacts with the second reaction gas to remove the residue layer while forming a protection layer on the surface of the semiconductor structure; wherein the protection layer comprises a polysilicon layer.