Analysis of Line-edge Roughness in Resist Patterns and Its Transferability as Origins of Device Performance Degradation and Variation

Abstract

General property of line-edge roughness (LER) in resist pattern and its transferability to under-lying layer were investigated. Longer-period components were found to have larger amplitudes in a resist pattern and to remain after dry etching. In addition, long-period LER strongly affects a transistor performance. Long-period LER in resist patterns, therefore, is as important as short-period LER. Metrology of LER was reconsidered to evaluate the both LER properly, and a guideline for choosing measurement parameters was proposed from a viewpoint of device performance estimation.