Bottom anti-reflective coatings for DUV lithography

Abstract

Bottom anti-reflective coatings (BARC) provide a production proven solution to improve linearity, depth-of-focus, CD control and process latitudes of photoresists. A series of BARCs compatible with chemically amplified deep ultra-violet (DUV) photoresists exhibiting different k values ranging from 0.1 to 0.6 at the DUV wavelength (248 nm) has been developed. The relationship between the k values and the etch rates of the BARC polymers with different dye concentrations in the polymer has been investigated. As a result, BARCs with targeted k values and etch rates can be provided. Formulation aspects of the BARC materials including edge bead remover (EBR) compatibility and evaluation results of these BARCs with different DUV resists are also discussed. ©1997TAPJ.