Time-dependent characterization of total electron yield and outgassing in model EUV resist materials

As technology nodes shrink, EUV photoresists are critical for high-resolution nanopatterning. However, slow electrons (below 20 eV) generated during EUV exposure can cause electron blur and defect formation through unintended chemical reactions. Understanding the behavior of these electrons is crucial for improving resist performance. This work aims to study how different resist materials, particularly photoacid generators (PAGs) and quenchers, influence electron-induced chemistry under EUV exposure. Additionally, the goal is to develop high-throughput methods to screen hundreds of samples efficiently. Simultaneous total electron yield (TEY) and residual gas analysis (RGA) were used to investigate electron behavior in various polymers and model resists during EUV exposure. TEY measured electron generation and capture, while outgassing experiments explored molecular bond scission. The methods are designed for high-throughput analysis, allowing rapid sample evaluation. TEY measurements showed that PAGs and quenchers significantly affect electron generation and capture. Combined TEY and outgassing results revealed insights into EUV-induced molecular bond scission and the correlation to the resist sensitivity. This study highlights the importance of optimizing resist composition to control slow-electron behavior and outgassing. The developed high-throughput screening methods can accelerate the evaluation and development of next-generation EUV photoresists.