Patent ID: 8124495
Filing Date: 2012-02-28
Classification: H01L

Abstract:
1. A method of manufacturing an alignment structure based on a substrate, the method comprising: forming an alignment feature located over the substrate, the alignment feature configured to align a photolithography process tool with the substrate; forming an anti-reflection layer having a first portion over the alignment feature and a second portion over areas surrounding the alignment feature; removing the first portion of the anti-reflection layer to expose a portion of the alignment feature for alignment with the photolithography process tool the removing causing the anti-reflection layer to have an opening directly above the alignment feature; forming a planarization layer having a first portion over the alignment feature and a second portion over the second portion of the anti-reflection layer, the first portion of the planarization layer substantially filling in the opening in the anti-reflection layer; and forming an optical filtration layer over the planarization layer, the optical filtration layer having a thickness configured to filter a desired range of radiation.