METHOD FOR PLANARIZING DIOXIDE SILICON LAYER ON NITRIDE SILICON IN SEMICONDUCTOR DIE

摘要

PURPOSE: A method for planarizing a semiconductor die is provided to maintain a pillar-to-gap ratio by planarizing a dioxide silicon layer on a nitride silicon in the semiconductor die. CONSTITUTION: A plurality of semiconductor dies which are substantially isolated from one another by scribe lines on a semiconductor wafer(10) and has a flat surface, respectively, are defined. A second material layer having an upper surface substantially parallel with the flat surface is formed. A first material layer is formed on the upper surface. A mask having a plurality of locations where densities of gap to pillar ratios proportionate to the height of the first material are different from one another is formed while penetrating the wafer. The first material is etched to penetrate the wafer through each gap of the mask. A CMP(Chemical Mechanical Polishing) is used to planarize the first material with respect to the upper surface across the wafer.