Reducing resist residue defects in open area on patterned wafer using trim mask

摘要

One aspect of the present invention relates to a method for reducing resist residue defects on a wafer structure. The method involves providing a semiconductor structure having a photoresist, the photoresist comprising open areas and circuit areas thereon; irradiating the open areas and circuit areas through a first photomask with a first energy dose to effect an image-wise pattern in the photoresist; irradiating the open areas of the photoresist through a second photomask with a second energy dose; and developing the photoresist.