# US 12,068,208 B2 · Plasma processing apparatus and control method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,068,208 B2 - Document ID: US12068208B2 - Status: Granted - Kind: B2 - Application number: 17/475,736 - Filed: 2021-09-15 - Published: 2022-01-06 - Granted: 2024-08-20 - Earliest claimed: 2017-04-14 - Assignees: Tokyo Electron Limited - Applicants: Tokyo Electron Limited - Inventors: Taro Ikeda; Yuki Osada - Web page: https://patentgrep.com/patent/US12068208B2 ## CPC - H10P 74/235: {comprising optical enhancement of defects or not-directly-visible states} - C23C 14/54: Controlling or regulating the coating process - C23C 16/45508: {Radial flow} - C23C 16/4558: {Perforated rings} - C23C 16/511: using microwave discharges - C23C 16/52: Controlling or regulating the coating process {(C23C16/45557, C23C16/279 take precedence)} - C23C 16/54: Apparatus specially adapted for continuous coating - H01J 37/32192: {Microwave generated discharge (H01J37/32357, H01J37/32366, H01J37/32394, H01J37/32403 take precedence)} - H01J 37/32935: {Monitoring and controlling tubes by information coming from the object and/or discharge} - H01J 37/32954: {Electron temperature measurement} - H01J 37/3299: {Feedback systems} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - H01J 37/32972: {Spectral analysis} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract A method of controlling plasma includes providing a plasma processing apparatus that includes N microwave introducing radiators disposed in a circumferential direction of a ceiling plate of a processing container so as to introduce microwaves for generating plasma into the processing container, wherein N≥2; and M sensors and configured to monitor at least one of electron density Ne and electron temperature Te of the plasma generated in the processing container, wherein M equals to N or a multiple of N. The method further includes controlling at least one of a power and a phase of the microwaves introduced from the microwave introducing radiators based on at least one of electron density Ne and electron temperature Te of the plasma monitored by the M sensors. ## Claims ### Claim 1 A method of controlling plasma, the method comprising: providing a plasma processing apparatus including: N microwave introducing radiators disposed in a circumferential direction of a ceiling plate of a processing container so as to introduce microwaves for generating plasma into the processing container, wherein N≥2; and M sensors protruding from an inner wall surface of a cylindrical wall of the processing container toward an inside of the processing container and configured to monitor at least one of electron density Ne and electron temperature Te of the plasma generated in the processing container, wherein M equals to N or a multiple of N, wherein the N microwave introducing radiators are disposed at positions symmetrical with respect to a central axis of the processing container, and controlling at least one of a power and a phase of the microwaves introduced from the microwave introducing radiators based on at least one of electron density Ne and electron temperature Te of the plasma monitored by the sensors. ### Claim 2 (depends on 1) The method according to claim 1, wherein the M sensors are provided in correspondence with the N microwave introducing radiators, respectively, the method further comprising: controlling at least one of the power and phase of the microwaves introduced from each of the N microwave introducing radiators based on at least one of the electron density Ne and the electron temperature Te of the plasma monitored by each of the M sensors provided in corresponding to the N microwave introducing radiators, respectively. ### Claim 3 (depends on 2) The method according to claim 2, wherein the controlling is performed in real-time based on at least one of the electron density Ne and the electron temperature Te of the plasma monitored by each of the M sensors provided in corresponding to each of the N microwave introducing radiators. ### Claim 4 (depends on 1) The method according to claim 1, wherein the N microwave introducing radiators includes a central microwave introducing radiator and a peripheral microwave introducing radiator, and the phase of the microwaves from the central microwave introducing radiator and the peripheral microwave introducing radiator is controlled to change distribution of the plasma. ### Claim 5 (depends on 1) The method according to claim 1, wherein the N microwave introducing radiators includes a central microwave introducing radiator and a peripheral microwave introducing radiator, and the power of the microwaves from the central microwave introducing radiator and the peripheral microwave introducing radiator is controlled to change distribution of the plasma. ### Claim 6 (depends on 1) The method according to claim 1, wherein the controlling includes applying voltages with sine wave to the M sensors, measuring electric current flowing through the M sensors, and transforming a waveform of the electric current through Fourier transform, thereby calculating the electron density Ne and the electron temperature Te of the plasma. ### Claim 7 (depends on 1) The method according to claim 1, wherein the plasma processing apparatus further comprising: a plurality of gas supply nozzles protruding toward the inside of the processing container, and disposed at different positions from the N microwave introducing radiators in the circumferential direction of the ceiling plate so as to be symmetrical with respect to the central axis of the processing container, the plurality of gas supply nozzles being configured to supply a processing gas to the processing container. ### Claim 8 (depends on 1) The method according to claim 1, wherein each of the M sensors includes a metallic portion coated with an insulating material. ### Claim 9 A method of controlling plasma, the method comprising: providing a plasma processing apparatus including: a processing container having a ceiling plate and a cylindrical wall, the cylindrical wall including an inner wall surface and an outer wall surface; a plurality of amplifiers each configured to output microwaves to the processing container; a plurality of microwave introducing radiators provided in corresponding to the plurality of amplifiers, respectively, and disposed in a circumferential direction of the ceiling plate of the processing container so as to introduce microwaves from the plurality of amplifiers into the processing container thereby generating plasma in the processing container; and a plurality of sensors embedded in the cylindrical wall of the processing container corresponding to the plurality of microwave introducing radiators and protruding from the inner wall surface of the cylindrical wall of the processing container toward an inside of the processing container, each of the plurality of sensors being configured to monitor at least one of electron density Ne and electron temperature Te of the plasma generated in the processing container, wherein the plurality of microwave introducing radiators are disposed at positions symmetrical with respect to a central axis of the processing container, and controlling at least one of a power and a phase of the microwaves introduced from the microwave introducing radiators based on at least one of electron density Ne and electron temperature Te of the plasma monitored by the plurality of sensors. ### Claim 10 (depends on 9) The method according to claim 9, wherein the plurality of sensors are provided in correspondence with the plurality of microwave introducing radiators, respectively, the method further comprising: controlling at least one of the power and phase of the microwaves introduced from each of the microwave introducing radiators based on at least one of the electron density Ne and the electron temperature Te of the plasma monitored by each of the sensors provided in corresponding to the microwave introducing radiators, respectively. ### Claim 11 (depends on 10) The method according to claim 10, wherein the controlling is performed in real-time based on at least one of the electron density Ne and the electron temperature Te of the plasma monitored by each of the sensors provided in corresponding to each of the microwave introducing radiators. ### Claim 12 (depends on 9) The method according to claim 9, wherein the microwave introducing radiators includes a central microwave introducing radiator and a peripheral microwave introducing radiator, and the phase of the microwaves from the central microwave introducing radiator and the peripheral microwave introducing radiator is controlled to change distribution of the plasma. ### Claim 13 (depends on 9) The method according to claim 9, wherein the microwave introducing radiators includes a central microwave introducing radiator and a peripheral microwave introducing radiator, and the power of the microwaves from the central microwave introducing radiator and the peripheral microwave introducing radiator is controlled to change distribution of the plasma. ### Claim 14 (depends on 9) The method according to claim 9, wherein the controlling includes applying voltages with sine wave to the sensors, measuring electric current flowing through the sensors, and transforming a waveform of the electric current through Fourier transform, thereby calculating the electron density Ne and the electron temperature Te of the plasma. ### Claim 15 (depends on 14) The method according to claim 14, wherein each of the plurality of the amplifiers includes a variable gain amplifier, and the controlling includes adjusting the variable gain amplifier to adjust a plasma intensity of the microwaves to be introduced into the plurality of microwave introducing radiators. ### Claim 16 (depends on 14) The method according to claim 14, wherein each of the plurality of the amplifiers includes a phase shifter, and the controlling includes adjusting the phase shifter to adjust a phase of the microwaves to be introduced into the plurality of microwave introducing radiators. ### Claim 17 (depends on 9) The method according to claim 9, wherein the plasma processing apparatus further comprising: a plurality of gas supply nozzles protruding toward the inside of the processing container and disposed at different positions from the plurality of microwave introducing radiators in the circumferential direction of the ceiling plate so as to be symmetrical with respect to the central axis of the processing container, the plurality of gas supply nozzles being configured to supply a processing gas to the processing container. ### Claim 18 (depends on 9) The method according to claim 9, wherein each of the plurality of sensors includes a metallic portion coated with an insulating material.