# US 2014/0190529 A1 · Apparatus and method for edge bevel removal of copper from silicon wafers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190529 A1 - Document ID: US20140190529A1 - Status: Published application - Kind: A1 - Application number: 13/857,883 - Filed: 2013-04-05 - Published: 2014-07-10 - Earliest claimed: 2008-08-27 - Assignees: Novellus Systems, Inc. - Inventors: Kousik Ganesan; Shanthinath Ghongadi; Tariq Majid; Aaron Labrie; Steven T. Mayer - Web page: https://patentgrep.com/patent/US20140190529A1 ## CPC - H10P 72/0424: {using mainly spraying means, e.g. nozzles} - H10P 50/667: {by liquid etching only} - H10P 70/27: {during, before or after processing of conductive materials, e.g. polysilicon or amorphous silicon layers} - H10P 70/54: {Cleaning of wafer edges} - H10P 70/56: {Cleaning of wafer backside} - H10P 72/3304: {characterised by movements or sequence of movements of transfer devices} - H10P 72/7611: {characterised by edge profile or support profile} - H10P 72/7624: {characterised by the mechanical construction of the susceptor, stage or support} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract Chemical etching methods and associated modules for performing the removal of metal from the edge bevel region of a semiconductor wafer are described. The methods and systems provide the thin layer of pre-rinsing liquid before applying etchant at the edge bevel region of the wafer. The etchant is less diluted and diffuses faster through a thinned layer of rinsing liquid. An edge bevel removal embodiment involving that is particularly effective at reducing process time, narrowing the metal taper and allowing for subsequent chemical mechanical polishing, is disclosed. ## Claims ### Claim 1 An apparatus for removing unwanted metal deposited on an edge bevel area of a semiconductor wafer, the apparatus comprising: a process chamber; a wafer chuck for supporting and rotating the wafer during removal of the edge bevel area; and a controller comprising: program instructions for rotating the wafer; program instructions for prerinsing the wafer using a prerinse liquid; program instructions for increasing the rotational speed of the wafer thereby thinning a layer of the prerinse liquid; and program instructions for delivering a stream of liquid etchant into the thinned layer of prerinse liquid near the edge bevel area of the rotating wafer. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising a deflector shield positioned around the wafer chuck and configured to deflect the prerinse liquid away from the surface of the wafer. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the prerinse liquid is deflected downward toward the bottom of process chamber. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the deflector shield is attached to the bottom of the process chamber. ### Claim 5 (depends on 3) The apparatus of claim 3, wherein the deflector shield is attached to the wafer chuck and rotates together with the wafer chuck. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the program instructions for increasing the rotational speed of the wafer include instructions for rotating the wafer at a rotational speed of at least about 600 rpm. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the program instructions for increasing the rotational speed of the wafer comprise instructions for rotating the wafer at a rotational speed of at least about 900 rpm. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the program instructions for prerinsing the wafer specify prerinsing for less than about 10 seconds. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the program instructions for prerinsing the wafer specify prerinsing for less than about 5 seconds. ### Claim 10 (depends on 1) The apparatus of claim 1, wherein the program instructions for delivering a stream of liquid etchant specify delivering the stream for less than about 30 seconds. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein the program instructions for delivering a stream of liquid etchant specify delivering the stream for less than about 25 seconds. ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the controller further comprises program instructions for rinsing at least some of the liquid etchant from the wafer. ### Claim 13 (depends on 12) The apparatus of claim 12, wherein the program instructions for rinsing include instructions for rotating the wafer at a rotational speed of at least about 600 rpm. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the program instructions for rinsing include instructions for rotating the wafer at a rotational speed of at least about 900 rpm. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein the program instructions for delivering a stream of liquid etchant include: instructions for delivering a first stream of liquid etchant at a first flow rate and for a first duration; and instructions for delivering a second stream of liquid etchant, after the first stream, at a second flow rate and for a second duration, the second flow rate substantially less than the first flow rate, the second duration substantially longer than the first duration. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein: the first flow rate is between about 0.25 and 0.35 ml/sec; and the second flow rate is between about 0.10 and 0.20 ml/sec. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein: the first duration is between about 1 and 5 seconds; and the second duration is between about 10 and 30 seconds. ### Claim 18 An apparatus for removing unwanted metal deposited on an edge bevel area of a semiconductor wafer, the apparatus comprising: a process chamber; a wafer chuck for supporting and rotating the wafer during removal of the edge bevel area; and a controller comprising: program instructions for rotating the wafer; program instructions for prerinsing the wafer using a prerinse liquid; program instructions for delivering a stream of a thinning liquid into a layer of the prerinse liquid near the edge bevel area of the rotating wafer thereby thinning the layer of the prerinse liquid; and program instructions for delivering a stream of liquid etchant into the thinned layer of prerinse liquid near the edge bevel area of the rotating wafer. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the thinning liquid comprises isopropyl alcohol, acetone, and/or a solution of water with a surfactant. ### Claim 20 An apparatus for removing unwanted metal deposited on an edge bevel area of a semiconductor wafer, the apparatus comprising: a process chamber; a wafer chuck for supporting and rotating the wafer during removal of the edge bevel area; and a controller comprising: program instructions for rotating the wafer; program instructions for prerinsing the wafer using a prerinse liquid; program instructions for delivering a stream of a thinning liquid into a layer of the prerinse liquid near the edge bevel area of the rotating wafer thereby thinning a layer of the prerinse liquid; program instructions for delivering a vapor or aerosol of a thinning agent over a layer of the prerinse liquid near the edge bevel area of the rotating wafer thereby thinning the layer of the prerinse liquid; and program instructions for delivering a stream of liquid etchant into the thinned layer of prerinse liquid near the edge bevel area of the rotating wafer. ### Claim 21 An apparatus for removing unwanted metal deposited on an edge bevel area of a semiconductor wafer, the apparatus comprising: a process chamber; a wafer chuck for supporting and rotating the wafer during removal of the edge bevel area; and a controller comprising: program instructions for rotating the wafer; program instructions for prerinsing the wafer using a prerinse liquid; program instructions for delivering a stream of a thinning liquid into a layer of the prerinse liquid near the edge bevel area of the rotating wafer thereby thinning a layer of the prerinse liquid; program instructions for heating a layer of the prerinse liquid thereby thinning the layer of the prerinse liquid; and program instructions for delivering a stream of liquid etchant into the thinned layer of prerinse liquid near the edge bevel area of the rotating wafer.