Patent ID: 6815367
Filing Date: 2004-11-09
Classification: G03F,H01L

Abstract:
A process of eliminating resist footing on a hardmask when preparing a semiconductor wafer stack, comprising:a) depositing a layer of BARC hardmask material on a substrate; b) subjecting the BARC hardmask to oxygen under conditions sufficient to produce an oxide cap layer and provide a hardmask/oxide cap layer with a substrate reflectivity below 0.8%; c) depositing a layer of SiO2 directly onto the hardmask/oxide cap layer, said layer of SiO2 having a thickness of between 20 nm and about 32 nm; d) forming a layer of photoresist on the layer of SiO2; e) patterning and developing the layer of photoresist by exposing photoresist; and f) etching exposed portions of the layer of hardmask/oxide cap layer/SiO2 layer to obtain a semiconductor wafer stack with no standing waves and free from resist footing.