ATTENUATED PSM WITH ASSIST FEATURES AND MANUFACTURING METHOD FOR THE SAME

摘要

An attenuated PSM with assist patterns and a manufacturing method for the same are provided to implement the depth of a focus in exposure processes by increasing remaining margin to apply assist pattern introduction effectively. An attenuated PSM(Phase Shift Mask) comprises a transparent mask substrate(100), mask patterns(201) of a halftone layer and assist patterns(301). The mask patterns of a first halftone layer are formed for a target pattern to be transcribed on a wafer. The assist patterns have smaller light transmittance than that of the mask pattern. And the assist patterns comprise a complex layer of a second halftone layer with higher light transmittance than those of the first halftone layer and the first halftone layer.