Patent ID: 6586142
Filing Date: 2003-07-01
Classification: G03F

Abstract:
A method for forming a photoresist mask, on a wafer, for generating, through etching, a line pattern having specific dimensions, including lines having ends, comprising:providing a primary reticle that bears an enlarged image of said line pattern; directing light through an optical reduction system, that includes said primary reticle, whereby an image of said line pattern is focused onto a layer of photoresist, with light impinging on the photoresist for a first time period that is sufficient to exceed the activation threshold of any previously unexposed resist; providing a correction reticle that bears a pattern of rectangles and replacing the primary reticle with the correction reticle in the optical reduction system; then directing light through the optical reduction system, whereby an image of said rectangles is focused onto the layer of photoresist, said rectangles being aligned so as to overlap said line ends by an amount, with light impinging on the photoresist for a second time period that is insufficient to exceed the activation threshold of any previously unexposed resist; and then developing the photoresist, thereby forming an etch mask that defines a pattern of lines having said specific dimensions as well as undistorted ends.