Patent ID: 6849518
Filing Date: 2005-02-01
Classification: H01L

Abstract:
1. A method, comprising: forming a mask layer on a substrate having a first area and a second area; forming a first photoresist layer over said mask layer; patterning the first photoresist layer to form a photoresist-mask layer over the first and second areas with the photoresist-mask layer having a plurality of openings; etching said mask layer and substrate, between the plurality of openings, to a first depth, to form a plurality of trenches in the substrate, said plurality of trenches defining a plurality of substrate structures covered by the mask layer; forming a second photoresist layer over said first area and leaving the trenches and substrate structures in the second area exposed; and etching the exposed trenches in the second area to a second depth, said mask layer protecting the substrate structures in the second area from being etched.