Multi-Trigger Resists: Modeling and Simulation Results

Abstract

The Multi-Trigger Resist (MTR), a novel negative tone photoresist, shows significant potential for extreme ultraviolet (EUV) lithography, offering lower dose to size (DtS) requirements compared to chemically amplified resists (CARs) and metal oxide resists (MORs). This research develops and validates a stochastic model of the Multi-Trigger Resist process. The model accounts for statistical variations in photon distribution, secondary electron generation, and molecular distribution within the photoresist. First simulation results show a good reproduction of experimental data. Current studies refine the existing MTR model with updated calibration data and expands the analysis to better understand roughness effects. Simulation results closely reproduce experimental trends, capturing critical dimension (CD) and line-edge roughness (LER) behaviors. An exploratory study of PAG loading reveals that increasing PAG concentration improves sensitivity and reduces roughness up to an intermediate optimum, while under-loading raises dose requirements and produces a LER upturn, most pronounced at 28-nm pitch. These results define a practical PAG loading window that balances DtS and LER performance, providing guidance for future MTR formulation and process optimization.