Effect of Alternative Developer Solutions on EUVL Patterning

This work explores the application of alternative developer solutions (“developers”) with aim understanding their potential effectivity in reduction resist-based stochastic pattern defects (or “stochastic defects”) extreme ultraviolet lithography (EUVL). Specifically, a quaternary ammonium hydroxide type aqueous developer; ethyltrimethylammonium (ETMAH) comparison to industry de facto standard alkali tetramethylammonium (TMAH) was investigated. Focusing on EUV exposed contact hole (CH) patterns typical chemically amplified resist (CAR), effect these developers were assessed. As result, patterning investigations showed that lithographic performance CAR developed ETMAH is comparable those obtained TMAH. In situ dissolution analysis using high-speed atomic force microscope (HS-AFM) confirms this as it rate CH formation during both are relatively same. Moreover, also understood compared commonly used concentration 0.26N, lower 0.20N resulted defect margin improvement, while maintaining performance. an obvious slowing down at concentration, suggesting possibility over-dissolution higher condition, translating increase merging defects. The results from study show advantages further pursuing optimal for EUVL. especially significant findings indicate how mitigate