Method of blind border pattern layout for attenuated phase shifting masks

摘要

A mask and method of forming a mask which minimizes the light transmission in the border regions of attenuating phase shifting masks. The mask uses square contact holes formed in the attenuating phase shifting material in the border regions. The square contact holes are located at the edge of the mask pattern region beginning at each corner of the mask pattern region and working toward the center of each side of the mask pattern region using a contact hole pitch. At the center of each side of the mask pattern region the pitch is discontinuous and a row of rectangular contact holes are formed.