# US 2012/0074099 A1 · Methods for Controlling Bevel Edge Etching in a Plasma Chamber > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2012/0074099 A1 - Document ID: US20120074099A1 - Status: Published application - Kind: A1 - Application number: 13/300,483 - Filed: 2011-11-18 - Published: 2012-03-29 - Earliest claimed: 2005-09-27 - Assignees: Lam Research Corporation - Inventors: Tong Fang; Yunsang Kim; Andrew D. Bailey, III; Olivier Rigoutat; George Stojakovic - Web page: https://patentgrep.com/patent/US20120074099A1 ## CPC - H01J 37/32449: {Gas control, e.g. control of the gas flow} - H01J 37/32091: {the radio frequency energy being capacitively coupled to the plasma} - H10P 70/54: {Cleaning of wafer edges} - H01J 2237/3341: Reactive 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 Methods for bevel edge etching are provided. One example method is for etching a film on a bevel edge of a substrate in a plasma etching chamber. The method includes providing the substrate on a substrate support in the plasma etching chamber. The plasma etching chamber has a top edge electrode and a bottom edge electrode disposed to surround the substrate support. Then flowing an etching process gas through a plurality of edge gas feeds disposed along a periphery of the gas delivery plate. The periphery of the gas deliver plate is oriented above the substrate support and the bevel edge of the substrate, and the flowing is further directed to a space between the top edge electrode and bottom edge electrode. And, flowing a tuning gas through a center gas feed of the gas delivery plate. ## Claims ### Claim 1 A method of etching a thin film on a bevel edge of a substrate in a plasma etching chamber, comprising: placing the substrate on a substrate support in the plasma etching chamber; flowing an etching process gas through a center gas feed or an edge gas feed, wherein the center gas feed and the edge gas feed are disposed above the substrate support; flowing a tuning process gas through the center gas feed or the edge gas feed, wherein the tuning gas is used to change the etching plasma characteristics at the bevel edge; generating an etching plasma near the bevel edge of the substrate to etch the thin film on the bevel edge by powering a bottom edge electrode or a top edge electrode with a RF power source and grounding the edge electrode that is not powered by the RF power source, wherein the bottom edge electrode surrounds the substrate support and the top edge electrode surrounds the gas distribution plate, wherein the distance between the top edge electrode and the bottom edge electrode is less than about 1.5 cm to confine the treatment plasma; and etching the thin film by the generated etching plasma. ### Claim 2 (depends on 1) The plasma method of claim 1, wherein the thin film on the bevel edge being etched is selected from a group consisting of a dielectric film, a metal film, a photoresist film, a semiconductor film, or a combination of the these films. ### Claim 3 (depends on 1) The etching of claim 1, wherein the thin film is a dielectric film, and the etching process gas includes an oxygen-containing gas and a fluorine-containing gas. ### Claim 4 (depends on 1) The method of claim 1, wherein the tuning gas includes nitrogen or an inert gas. ### Claim 5 (depends on 1) The method of claim 1, wherein the distance between a gas delivery plate having the center gas feed and the surface of the substrate facing the gas delivery plate is less than about 0.6 mm to prevent plasma being formed between the gas delivery plate and the substrate. ### Claim 6 (depends on 1) The method of claim 1, wherein the etching plasma near the bevel edge has zero etching at greater than about 2 mm from an edge of the substrate. ### Claim 7 (depends on 1) The method of claim 1, wherein the etching process gas is fed from the edge gas feed and the tuning gas is fed from the center gas feed. ### Claim 8 A method of etching a film on a bevel edge of a substrate in a plasma etching chamber, comprising: providing the substrate on a substrate support in the plasma etching chamber, the plasma etching chamber having a top edge electrode and a bottom edge electrode disposed to surround the substrate support; positioning a gas delivery plate in the plasma processing chamber at a distance of less than about 0.6 mm from the substrate support; flowing an etching process gas through a plurality of edge gas feeds disposed along a periphery of the gas delivery plate, the periphery of the gas deliver plate being oriented above the substrate support and the bevel edge of the substrate, the flowing further directed to a space between the top edge electrode and bottom edge electrode; flowing a tuning gas through a center gas feed of the gas delivery plate, the tuning gas directed over a center region of the substrate so as to flow way from the center region and toward the bevel edge of the substrate and mix with the etching process gas; and applying RF power to one of the top or bottom edge electrodes, the applied power acting to strike a plasma to etch the film of the bevel edge of the substrate. ### Claim 9 (depends on 8) The method of claim 8, further comprising, arranging the a distance between the top and bottom edge electrodes to be less than about 1.5 cm. ### Claim 10 (depends on 8) The method of claim 8, wherein the film is a dielectric material and the etching process gas includes NF3 and CO2, and the tuning gas includes at least one of nitrogen (N2), argon (Ar), and helium (He). ### Claim 11 (depends on 8) The method of claim 8, wherein, the tuning gas provided from the center feed includes NF3 and CO2, and adjusting a flow rate of CO2. ### Claim 12 (depends on 11) The method of claim 11, wherein adjusting the flow rate of CO2 up increases etch rate in the bevel edge closer to an edge of the substrate. ### Claim 13 (depends on 12) The method of claim 12, wherein the flow rate of CO2 is adjusted between 200 sccm to 500 sccm. ### Claim 14 (depends on 11) The method of claim 11, further including N2 as an additional non-reactive gas supplied from the center feed. ### Claim 15 (depends on 8) The method of claim 8, wherein the flown etching process gas through the plurality of edge gas feeds is defined from an NF3 gas and a CO2 gas, and the tuning gas is N2 flown from the center gas feed. ### Claim 16 (depends on 15) The method of claim 15, wherein the tuning gas is provided with flow rate of between about 300 sccm and about 750 sccm. ### Claim 17 (depends on 15) The method of claim 15, wherein the tuning gas is provided as a mixture of two or more of N2, Ar, and He, setting the mixture provides for tuning an etching profile at the bevel edge of substrate.