# US 12,000,041 B2 · Processing chamber condition and process state monitoring using optical reflector attached to processing chamber liner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,041 B2 - Document ID: US12000041B2 - Status: Granted - Kind: B2 - Application number: 18/203,853 - Filed: 2023-05-31 - Published: 2023-09-28 - Granted: 2024-06-04 - Earliest claimed: 2020-06-12 - Assignees: Applied Materials, Inc. - Applicants: Applied Materials, Inc. - Inventors: Patrick Tae - Web page: https://patentgrep.com/patent/US12000041B2 ## CPC - C23C 16/4405: {Cleaning of reactor or parts inside the reactor by using reactive gases} - C23C 16/45536: {Use of plasma, radiation or electromagnetic fields} - G01N 21/211: {Ellipsometry (optical thickness measurement G01B11/06)} - G01N 21/31: Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} - G01N 21/55: Specular reflectivity - G01N 21/8422: {Investigating thin films, e.g. matrix isolation method} - H01J 37/32862: {In situ cleaning of vessels and/or internal parts} - H01J 37/32972: {Spectral analysis} - H10P 72/0402: {Apparatus for fluid treatment (H10P72/0441, H10P72/0448 take precedence)} - H10P 72/0604: {Process monitoring, e.g. flow or thickness monitoring} - H10P 72/53: {using optical controlling means} - G01N 2021/213: {Spectrometric ellipsometry} - G01N 2021/8416: {and process controlling, not otherwise provided for} - G01N 2021/8427: {Coatings} - 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) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - 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 method includes receiving light, by a light coupling device and along an optical path, reflected back from a reflector mounted on a liner of a processing chamber. The method further includes detecting, by a spectrometer within the received light, a first spectrum representative of a deposited film layer on the reflector. The method further includes aligning, using an alignment device, the light coupling device in two dimensions with reference to the reflector along the optical path until maximization of the light received by the light coupling device. ## Claims ### Claim 1 A method comprising: transmitting, by a light coupling device, light emitted from a light source through a window of a processing chamber directed at a reflector mounted on a liner of the processing chamber across from the window; focusing, by the light coupling device into a fiber optic cable, light received reflected back from the reflector along an optical path through the processing chamber and the window; receiving, by a spectrometer, the focused light from the fiber optic cable; detecting, by the spectrometer within the focused light, a first spectrum representative of a deposited film layer on the reflector; and aligning, by a first alignment device, the light coupling device in two dimensions with reference to the reflector along the optical path until maximization of the light received by the light coupling device. ### Claim 2 (depends on 1) The method of claim 1, further comprising: calibrating, by a controller, the alignment device in order to increase a signal-to-noise ratio (SNR) of the focused light above a threshold SNR; and wherein the aligning further comprises aligning, by a second alignment device, the reflector in the two dimensions in concert with aligning the light coupling device. ### Claim 3 (depends on 1) The method of claim 1, further comprising: receiving, by a processing device, the first spectrum from the spectrometer; receiving, by the processing device, from the spectrometer, a second spectrum when the light source is off; calculating, by the processing device, a reflectometry data by subtracting the second spectrum from the first spectrum; calculating, by the processing device, a reflectometry signal by dividing the reflectometry data by a reference spectrum; and fitting, by the processing device, the reflectometry signal to a thin film optical model to determine information comprising one or more optical film property of the deposited film layer. ### Claim 4 (depends on 3) The method of claim 3, wherein the one or more optical film property comprises thickness, the method further comprising, after processing a substrate within the processing chamber: detecting, by the processing device, that the thickness of the deposited film layer on the reflector has reached an accumulation limit; and in response to the detection, triggering the processing chamber to initiate a cleaning process in the processing chamber. ### Claim 5 (depends on 3) The method of claim 3, wherein the one or more optical film property comprises thickness, the method further comprising, while processing substrates within the processing chamber: detecting a moment in time when the deposited film layer has reached a threshold level of thickness; and triggering an end of a deposition process that is depositing the deposited film layer. ### Claim 6 A method comprising: receiving light, by a light coupling device and along an optical path, reflected from a reflector mounted on a liner of a processing chamber; detecting, by a spectrometer within the received light, a first spectrum representative of a deposited film layer on the reflector; and aligning, using an alignment device, the light coupling device in two dimensions with reference to the reflector along the optical path until maximization of the light received by the light coupling device. ### Claim 7 (depends on 6) The method of claim 6, further comprising: transmitting, by the light coupling device, light emitted from a light source through a window of the processing chamber directed at the reflector mounted on the liner of the processing chamber across from the window; and focusing, by the light coupling device into a fiber optic cable, the received light reflected from the reflector along the optical path through the processing chamber and the window; and receiving, by the spectrometer, the focused received light from the fiber optic cable. ### Claim 8 (depends on 6) The method of claim 6, further comprising: calibrating, by a controller, the alignment device in order to increase a signal-to-noise ratio (SNR) of the received light above a threshold SNR; and wherein the aligning further comprises aligning, using a second alignment device, the reflector in concert with aligning the light coupling device. ### Claim 9 (depends on 6) The method of claim 6, further comprising: receiving, by a processing device, the first spectrum from the spectrometer; receiving, from the spectrometer, a second spectrum when a light source for the received light is off; calculating a reflectometry data by subtracting the second spectrum from the first spectrum; calculating a reflectometry signal by dividing the reflectometry data by a reference spectrum; and fitting, by the processing device, the reflectometry signal to a thin film optical model to determine information comprising one or more optical film property of the deposited film layer. ### Claim 10 (depends on 9) The method of claim 9, wherein the one or more optical film property comprises thickness, the method further comprising, after processing a substrate within the processing chamber: detecting, by the processing device, that the thickness of the deposited film layer on the reflector has reached an accumulation limit; and in response to the detection, triggering the processing chamber to initiate a cleaning process in the processing chamber. ### Claim 11 (depends on 9) The method of claim 9, wherein the one or more optical film property comprises thickness, the method further comprising, while processing substrates within the processing chamber: detecting a moment in time when the deposited film layer has reached a threshold level of thickness; and triggering an end of a deposition process that is depositing the deposited film layer. ### Claim 12 A method comprising: collimating and directing, using a first collimator, light from a first light source onto a reflector attached to a liner of a processing chamber; collimating and directing, using a second collimator, light received reflected from the reflector into a spectrometer; detecting, within the received light, a first spectrum representative of a deposited film layer on the reflector; and aligning, in two dimensions, the first collimator with the reflector until maximization of the light received by the second collimator. ### Claim 13 (depends on 12) The method of claim 12, wherein the collimating and directing of the light from the first collimator is through a first window of the processing chamber and at an oblique angle onto the reflector, and wherein the collimating and directing of the received light is through a second window of the processing chamber, the method further comprising positioning the reflector within the processing chamber at a location partway between the first window and the second window. ### Claim 14 (depends on 12) The method of claim 12, further comprising focusing the received light, using the second collimator, into a fiber optic cable coupled to the spectrometer, the method further comprising receiving, by the spectrometer, the focused received light from the fiber optic cable. ### Claim 15 (depends on 12) The method of claim 12, further comprising: aligning, in two dimensions, the second collimator with reference to the reflector until maximization of the light received by the second collimator; and aligning the reflector in concert with aligning the first collimator with the reflector and aligning the second collimator with the reflector. ### Claim 16 (depends on 12) The method of claim 12, further comprising: receiving, by a processing device, the first spectrum from the spectrometer; receiving, from the spectrometer, a second spectrum when a light source is off; calculating a ellipsometry data via subtraction of the second spectrum from the first spectrum; calculating an ellipsometry signal via division of the ellipsometry data by a reference spectrum; and fitting, by the processing device, the ellipsometry signal to a thin film optical model to determine information comprising one or more optical film property of the deposited film layer. ### Claim 17 (depends on 16) The method of claim 16, wherein the one or more optical film property comprises thickness, and wherein, during processing substrates within the processing chamber, the method further comprising: comparing the thickness with a baseline measurement for the deposited film layer; determining, using the comparison, a variation in a rate of deposition of the deposited film layer that is beyond a threshold variation; and triggering a process within the processing chamber that is to correct the rate of deposition of the deposited film layer. ### Claim 18 (depends on 16) The method of claim 16, wherein the one or more optical film property comprises thickness, and wherein, during processing substrates within the processing chamber, the method further comprising: detecting a moment in time when the deposited film layer has reached a threshold level of thickness on the reflector; and triggering an end of a deposition process that is depositing the deposited film layer. ### Claim 19 (depends on 16) The method of claim 16, wherein the one or more optical film property comprises thickness, and wherein, after processing a substrate within the processing chamber, the method further comprising: detecting that the thickness of the deposited film layer on the reflector has reached an accumulation limit; and in response to the detection, triggering the processing chamber to initiate a cleaning process in the processing chamber. ### Claim 20 (depends on 16) The method of claim 16, wherein the one or more optical film property comprises thickness, and wherein, after processing a substrate within the processing chamber and during a cleaning process, the method further comprising: detecting a moment in time at which the deposited film layer on the reflector has been removed within a predetermined threshold thickness; and in response to the detection, triggering the processing chamber to end the cleaning process within the processing chamber.