# US 2022/0037162 A1 · Systems and Methods for Improving Planarity using Selective Atomic Layer Etching (ALE) > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0037162 A1 - Document ID: US20220037162A1 - Status: Published application - Kind: A1 - Application number: 16/944,563 - Filed: 2020-07-31 - Published: 2022-02-03 - Earliest claimed: 2020-07-31 - Assignees: Tokyo Electron Limited - Applicants: Tokyo Electron Limited - Inventors: David O'Meara; Anthony Dip; Masanobu Igeta - Web page: https://patentgrep.com/patent/US20220037162A1 ## CPC - H10P 50/283: {by chemical means} - H10P 95/064: {the removal being chemical etching} - C23C 16/04: Coating on selected surface areas, e.g. using masks - C23C 16/45551: {for relative movement of the substrate and the gas injectors or half-reaction reactor compartments} - C23C 16/45553: {characterized by the use of precursors specially adapted for ALD} - C23C 16/4584: {the substrate being rotated} - H01J 37/32513: {Sealing means, e.g. sealing between different parts of the vessel} - H01J 37/32779: {of batches of workpieces} - H01J 37/32899: {Multiple chambers, e.g. cluster tools} - H10P 50/285: {of materials not containing Si, e.g. PZT or Al2O3} - 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 Methods are provided for planarizing a patterned substrate in a spatial atomic layer processing system comprising a rotating platen. The patterned substrate may generally include features having higher regions and lower regions. To planarize the patterned substrate, or reduce a height differential between the higher and lower regions, a selective atomic layer etching (ALE) process is disclosed to preferentially form a modified layer on the higher regions of the features by exposing a surface of the patterned substrate to a precursor gas while the rotating platen spins at a high rotational speed. By preferentially forming the modified layer on the higher regions of the features, and subsequently removing the modified layer, the selective ALE process described herein preferentially etches the higher regions of the features to lessen the height differential between the higher and lower regions until a desired planarization of the features is achieved. ## Claims ### Claim 1 A method for planarizing a patterned substrate in a spatial atomic layer processing system, the method comprising: providing at least a first layer as part of the patterned substrate, wherein the first layer comprises at least a portion of one or more features formed on the patterned substrate, wherein the one or more features have higher regions and lower regions, and wherein a height differential exists between the higher regions and the lower regions; providing the patterned substrate on a rotating platen of the spatial atomic layer processing system; forming a modified layer on the first layer, at least one step of the forming the modified layer on the first layer being exposing a surface of the first layer to a first precursor gas, which adsorbs on and reacts with the surface of the first layer to produce the modified layer, wherein spinning the rotating platen at higher rotational speeds aids in the modified layer being preferentially formed onto the higher regions of the one or more features as compared to the lower regions of the one or more features; removing the modified layer, wherein the forming the modified layer on the first layer and the removing the modified layer preferentially etches the higher regions of the one or more features as compared to the lower regions of the one or more features so as to lessen the height differential between the higher regions of the one or more features and the lower regions of the one or more features; and repeating the steps of forming the modified layer and removing the modified layer so as to planarize the patterned substrate. ### Claim 2 (depends on 1) The method of claim 1, wherein a rotational speed of the rotating platen causes enhanced deposition of a first precursor of the first precursor gas on the higher regions of the one or more features as compared to the lower regions of the one or more features. ### Claim 3 (depends on 1) The method of claim 1, wherein a rotational speed of the rotating platen is selected from a range between 30 RPM and 240 RPM. ### Claim 4 (depends on 1) The method of claim 1, wherein the height differential between the higher regions and the lower regions is reduced by at least 50%. ### Claim 5 (depends on 1) The method of claim 1, wherein a rotational speed of the rotating platen is adjusted during one or more of the steps of forming the modified layer and removing the modified layer. ### Claim 6 (depends on 1) The method of claim 1, wherein a thickness of the modified layer is greater on the higher regions of the one or more features than on the lower regions of the one or more features. ### Claim 7 (depends on 1) The method of claim 1, wherein the first precursor gas comprises trimethylaluminum, BCl3, HF, Cl2, CF4/O2, and/or F2/He. ### Claim 8 (depends on 7) The method of claim 7, wherein the first layer comprises an oxide. ### Claim 9 (depends on 8) The method of claim 8, wherein removing the modified layer comprises a plasma removal step. ### Claim 10 (depends on 1) The method of claim 1, wherein removing the modified layer comprises a plasma removal step. ### Claim 11 (depends on 1) The method of claim 1, wherein the first layer comprises an oxide. ### Claim 12 A method for planarizing a patterned substrate in a spatial atomic layer processing system, the method comprising: providing the patterned substrate on a rotating platen of the spatial atomic layer processing system, wherein one or more features formed on the patterned substrate have higher regions and lower regions; spinning the rotating platen; exposing a surface of the patterned substrate to a precursor gas to form a modified layer on the patterned substrate, wherein a rotational speed of the rotating platen causes the modified layer to be preferentially formed on the higher regions of the one or more features; removing the modified layer so that the higher regions of the one or more features are preferentially etched as compared to the lower regions of the one or more features; and repeating the steps of exposing a surface of the patterned substrate to a precursor gas to form a modified layer and removing the modified layer to gradually reduce a height of the one or more features until a desired planarization of the one or more features is achieved, wherein the desired planarization reduces a height differential between the higher regions and the lower regions by at least 25%. ### Claim 13 (depends on 12) The method of claim 12, wherein the rotational speed of the rotating platen is selected from a range between 30 RPM and 240 RPM. ### Claim 14 (depends on 12) The method of claim 12, wherein the desired planarization reduces the height differential between the higher regions and the lower regions by at least 50%. ### Claim 15 (depends on 12) The method of claim 12, wherein the rotational speed of the rotating platen is adjusted during one or more of the steps of exposing a surface of the patterned substrate to a precursor gas to form a modified layer and removing the modified layer. ### Claim 16 (depends on 12) The method of claim 12, wherein the precursor gas comprises trimethylaluminum, BCl3, HF, Cl2, CF4/O2, and/or F2/He. ### Claim 17 (depends on 16) The method of claim 16, wherein the surface of the patterned substrate comprises an oxide. ### Claim 18 (depends on 12) The method of claim 12, wherein the surface of the patterned substrate comprises an oxide. ### Claim 19 (depends on 18) The method of claim 18, wherein the rotational speed of the rotating platen is above 200 RPM ### Claim 20 (depends on 12) The method of claim 12, wherein the removing the modified layer comprises a plasma removal step. ### Claim 21 A method for operating an atomic layer processing system to planarize a patterned substrate, the method comprising: providing at least a first layer as part of the patterned substrate, wherein the first layer comprises at least a portion of one or more features formed on the patterned substrate, wherein the one or more features have higher regions and lower regions, and wherein a height differential exists between the higher regions and the lower regions; providing the patterned substrate in the atomic layer processing system; forming a modified layer on the first layer, at least one step of the forming the modified layer on the first layer being exposing a surface of the first layer to a first precursor gas to produce the modified layer, wherein the modified layer being preferentially formed onto the higher regions of the one or more features as compared to the lower regions of the one or more features; removing the modified layer, wherein the forming the modified layer on the first layer and the removing the modified layer preferentially etches the higher regions of the one or more features as compared to the lower regions of the one or more features so as to lessen the height differential between the higher regions of the one or more features and the lower regions of the one or more features; and utilizing a controller to control at least one operating parameter of the atomic layer processing system to achieve a desired amount of planarization of the patterned substrate. ### Claim 22 (depends on 21) The method of claim 21, further comprising coupling a sensor to the controller, the sensor monitoring at least one parameter of the patterned substrate or the atomic layer processing system to provide sensor data to the controller, the sensor data being utilized to monitor a condition of the patterned substrate and/or the atomic layer processing system so that the controller controls the at least one operating parameter of the atomic layer processing system based at least in part on the sensor data. ### Claim 23 (depends on 22) The method of claim 22, wherein the sensor data is indicative of a thickness of at least a portion of the first layer. ### Claim 24 (depends on 23) The method of claim 23, wherein the forming the modified layer and the removing the modified layer are cyclically performed, the operating parameter being a number of cycles of the forming the modified layer and the removing the modified layer. ### Claim 25 An atomic layer processing system configured to planarize a patterned substrate, comprising: a spatial atomic layer processing chamber comprising a rotating platen; a sensor that provides sensor data related to a property of the patterned substrate and/or a reaction in the spatial atomic layer processing chamber; and a controller, the controller coupled to the sensor to receive the sensor data, the controller configured to utilize the sensor data to adjust at least one operating parameter of the atomic layer processing system so as to achieve a desired amount of planarization of the patterned substrate ### Claim 26 (depends on 25) The atomic layer processing system of claim 25, wherein the operating parameter is at least one of a rotational speed, a temperature, a gas flow, a gas ratio, a pressure, a vacuum level, or a number of cycles.