Arrangements for improving bevel etch repeatability among substrates

Abstract

An apparatus for improving bevel etch repeatability among substrates is provided. The apparatus includes an optical arrangement disposed to ascertain at least one bevel edge characteristic of a bevel edge of a substrate. The apparatus also includes a logic module for deriving at least one compensation factor from the at least one bevel edge characteristic. At least one compensation factor pertains to an adjustment in a bevel etch process parameter. The apparatus further includes a plasma processing chamber for performing bevel etching utilizing the at least one compensation factor.

1 - 20 . (canceled) 
     
     
         21 . An apparatus for improving repeatability in bevel etching among substrates, comprising:
 an optical arrangement disposed to ascertain at least one bevel edge characteristic of a bevel edge of a substrate of said substrates;   a logic module for deriving at least one compensation factor from said at least one bevel edge characteristic, said at least one compensation factor pertaining to an adjustment in a bevel etch process parameter; and   a plasma processing chamber for performing said bevel etching utilizing said at least one compensation factor.   
     
     
         22 . The apparatus of  claim 21  wherein said optical arrangement includes a camera disposed co-planarly with said substrate and directed tangentially at said bevel edge to obtain a side profile image of said substrate. 
     
     
         23 . The apparatus of  claim 22  wherein said at least one bevel edge characteristic is a fill-factor. 
     
     
         24 . The apparatus of  claim 21  wherein said bevel etch process parameter is one of a bevel etch time, bevel etch chemistry, inter-electrode gap, RF power, RF frequency and chamber pressure. 
     
     
         25 . The apparatus of  claim 21  wherein said optical arrangement includes a laser light source and an array of sensors configured to detect a reflected beam from said laser light source that reflects off said bevel edge. 
     
     
         26 . The apparatus of  claim 21  wherein said optical arrangement includes a camera, a light source, and at least one mirror, wherein said camera is disposed at an angle relative to a substrate plane of said substrate. 
     
     
         27 . The apparatus of  claim 21  wherein said optical arrangement is employed for obtaining a bevel edge thickness using said optical arrangement. 
     
     
         28 . The apparatus of  claim 21  wherein said optical arrangement includes an optical fiber to illuminate said bevel edge of said substrate from a remote light source, wherein said optical fiber is configured to capture an image of a side profile of said bevel edge from a remote camera. 
     
     
         29 . The apparatus of  claim 21  wherein said optical arrangement includes at least one light source and a set of sensors configured to ascertain variations in said bevel edge of said substrate. 
     
     
         30 . The apparatus of  claim 21  wherein said optical arrangement includes a mirror disposed such that a camera is employed to capture an image of a side profile of said bevel edge of said substrate. 
     
     
         31 . An arrangement for improving repeatability in bevel etching among substrates, comprising:
 a bevel edge detection arrangement disposed to ascertain at least one side profile of a bevel edge of a substrate of said substrates;   a logic module for deriving at least one feed-forward compensation factor from said at least one side profile, said at least one feed-forward compensation factor pertaining to an adjustment in a bevel etch process parameter; and   a plasma processing chamber for performing said bevel etching utilizing said at least one feed-forward compensation factor.   
     
     
         32 . The arrangement of  claim 31  wherein said bevel edge detection arrangement includes a camera disposed co-planarly with said substrate and is pointed tangentially at said bevel edge of said substrate to obtain an image of said at least one side profile of said substrate. 
     
     
         33 . The arrangement of  claim 32  wherein said bevel edge detection arrangement includes a light source positioned for illuminating said bevel edge of said substrate to enable said camera to capture said at least one side profile of said bevel edge of said substrate. 
     
     
         34 . The arrangement of  claim 33  wherein said optical arrangement includes at least one mirror disposed such that light from said bevel edge reflects off said at least one mirror to be received by said camera, wherein said camera is employed to capture said image of said at least one side profile of said bevel edge of said substrate. 
     
     
         35 . The arrangement of  claim 31  wherein said at least one feed-forward compensation factor includes a fill factor. 
     
     
         36 . The arrangement of  claim 31  wherein said bevel etch process parameter is one of a bevel etch time, bevel etch chemistry, inter-electrode gap, RF power, RF frequency and chamber pressure. 
     
     
         37 . The arrangement of  claim 31  wherein said bevel edge detection arrangement includes a laser light source and an array of sensors configured to detect a reflected beam from said laser light source that reflects off said bevel edge of said substrate. 
     
     
         38 . The arrangement of  claim 31  wherein said bevel edge detection arrangement includes a camera, a light source, and at least one mirror, wherein said camera is disposed at an angle relative to a substrate plane of said substrate. 
     
     
         39 . The arrangement of  claim 31  wherein said bevel edge detection arrangement includes an optical fiber to illuminate said bevel edge of said substrate from a remote light source, wherein said optical fiber is configured to capture an image of said at least one side profile of said bevel edge from a remote camera. 
     
     
         40 . An arrangement for improving repeatability in bevel etching among substrates, comprising:
 means for ascertainining at least one side profile of a bevel edge of a substrate of said substrates;   logic means for deriving at least one compensation factor from said at least one side profile, said at least one compensation factor pertaining to an adjustment in a bevel etch process parameter; and   a plasma processing chamber for performing said bevel etching utilizing said at least one feed-forward compensation factor.