Exposure correction based on reflective index for photolithographic process control
Critical dimension variation of photolithographically formed features on a semiconductor substrate is reduced by measuring the reflectivity of a photoresist layer and an underlying layer, such as a polysilicon layer, and adjusting the exposure level of the photoresist in accordance with the measured reflectivity. This allows precise control of feature width on the photoresist, which in turn allows precision etching of the underlying layer to accurately form a feature, such as a gate electrode.
Advanced Micro Devices, Inc.
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Y10S G03F
additional inventional
Warren T. Eric Zicheng Gary Jayendra D. Weizhong
Yu Kent Ling Bhakta Wang