Patent ID: 6686289
Filing Date: 2004-02-03
Classification: H01L,Y02P

Abstract:
A method for minimizing a variation in an etch rate of a semiconductor wafer caused by a variation in a mask pattern density, the method comprising:determining a reference amount of an etch gas according to a reference mask pattern density; obtaining an optimized amount of the etch gas according to a mask pattern density different from the reference mask pattern density, wherein the optimized amount is obtained by the following equation: (the&it;â€ƒ&it;reference&it;â€ƒ&it;amount&it;â€ƒ&it;according&it;â€ƒ&it;to&it;â€ƒ&it;the&it;â€ƒ&it;reference&it;â€ƒ&it;mask&it;â€ƒ&it;patterndensity)Ã—(1-the&it;â€ƒ&it;mask&it;â€ƒ&it;pattern&it;â€ƒ&it;density)(1-the&it;â€ƒ&it;reference&it;â€ƒ&it;mask&it;â€ƒ&it;pattern&it;â€ƒ&it;density),and the mask pattern density is a value of dividing a mask pattern area by an overall semiconductor wafer area; andapplying the optimized amount of the etch gas in an etching process of the semiconductor wafer.