Investigations on the application of aqueous ethyltrimethylammonium hydroxide (ETMAH) as an alternative developer solution for extreme ultraviolet lithography (EUVL) were carried out. Utilizing a widely-used chemically amplified resist, it was found that the ETMAH developer solution has no negative impact on lithographic performance; resolution, line width / line edge roughness, and sensitivity (compared to the de facto standard aqueous tetramethylammonium hydroxide or TMAH). Stochastic defectivity analysis was performed by considering the effect of line-break (in the overdose region) and line-bridge defects (in the underdose region), on exposure latitude (ELX) and critical dimension or CD margin (CDMX). Results show that the ETMAH improves ELX and CDMX by around 10% and 5%, respectively at a lower developer solution concentration of 0.20N. These results confirmed the capability of the ETMAH in reducing resist-based stochastic defects, demonstrating its potential as an alternative developer solution for EUVL.
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