Patent ID: 6187486
Filing Date: 2001-02-13
Classification: G03F

Abstract:
A method of multi-exposure for improving photolithography resolution that comprises the step of:providing a wafer having a photoresist formed thereon;providing a photomask aligned above with the wafer;performing a first exposure to simultaneously form a first exposed region and an unexposed region in the photoresist;performing a first shift of the wafer parallel to the photomask resulting in a first relative and parallel shift movement, wherein the first relative and parallel shift movement has a first direction and a first relative shift distance;performing a second exposure to convert a portion of the unexposed region adjacent to the first exposed region into a second exposed region in the photoresist;performing a second shift of the wafer parallel to the photomask resulting in a second relative and parallel shift movement, wherein the second relative and parallel shift movement has a second direction and a second relative shift distance;performing a third exposure to convert a portion of the remaining unexposed region adjacent to the first exposure into a third exposed region in the photoresist; andperforming a development of the photoresist.