Comparison of photoresist sensitivity between KrF, EB, and EUV exposure

EUV lithography technology has started to be used for the fabrication of 7 nm logic devices, and has been used for mass production technology since 2020. As EUV lithography plays a more important role in semiconductor manufacturing, photoresists for EUV exposure also become more important. However, there are few places in Japan where we can use EUV exposure tool. To solve this problem, it is effective to evaluate photoresists by other wavelengths such as 248 nm to screen samples in the initial stage. In our former report, we have evaluated the correlation between KrF, EB and EUV exposure, and we showed that there are good correlations among them. In this report, we synthesized acrylic polymers by changing the ratio of protection group or molecular weight. Acrylic monomers using this report are commercially available, for example a protection group type and a lactone polarity type. Using these samples, the evaluations by KrF, ArF and EUV exposure were performed, respectively.