Evaluation of EUV resists for 5nm technology node and beyond

Abstract

For more than a decade, the semiconductor manufacturing industry has anticipated the introduction of Extreme Ultraviolet Lithography (EUVL) into high-volume manufacturing (HVM). The readiness of the supporting EUV resists is one of the requirements for HVM. While the industry is planning to introduce EUVL into HVM at 7 nm node, it is important to address the availability of the resists for future generations and in particular for the high-NA EUVL which will have the patterning capability down to 8 nm half-pitch. In this study we report on the performance of promising EUV resists evaluated by EUV interference lithography (EUV-IL) at the Swiss Light Source (SLS) at the Paul Scherrer Institut (PSI). We evaluated EUV resists that are being developed as candidate materials for future technology nodes and we assessed their potential for high-NA EUV lithography. Several new chemically-amplified resists (CARs) and non-CAR resists have been investigated with the aim to resolve patterns down to 10 nm hp. While, up to now, CARs performance reached down to 13 nm half pitch (hp) only, we report about a recent CAR that can partially resolve lines down to 11 nm hp. Moreover, some other non-CAR resists have achieved resolutions down to 10 nm. We evaluated essential parameters, such as critical dimension (CD) and line edge roughness as a function of dose and we estimated the exposure latitude (EL). Furthermore, we report on the ultimate extendibility of CAR platform materials in manufacturing, and on novel resist platforms developed to address the challenges in the patterning at hp ≤ 10 nm.