Patent ID: 7534533
Filing Date: 2009-05-19
Classification: G03F,G06F,Y02P

Abstract:
1. An exposure method comprising: forming a first resist pattern over a step pattern disposed on a wafer by a first light, the first resist pattern being perpendicular to the step pattern, the first light being polarized parallel to the step pattern; obtaining a first relation between a ratio of a space to a line width of the first resist pattern and a first residual resist on the wafer, the first residual resist remaining at an orthogonal point of the step pattern and the first resist pattern; forming a second resist pattern over the step pattern disposed on the wafer by a second light, the second resist pattern being perpendicular to the step pattern, the second light being polarized perpendicular to the step pattern; obtaining a second relation between a ratio of a space to a line width of the second resist pattern and a second residual resist on the wafer, the second residual resist remaining at an orthogonal point of the step pattern and the second resist pattern formed by the second light; and choosing an optimum polarization direction reducing residual resists by comparing the first and second relations.