Mesoscale simulation of the line-edge structure during positive and negative tone resist development process

Abstract

Recent studies have shown that the semiconductor industry is seeking the possibility of utilizing both positive tone photoresist development (PTD) and negative tone photoresist development (NTD) to pursue ultimate pattern resolution. In particular, a minimal line edge roughness (LER) is one of the key performance indicators. Our current work is aimed at studying mechanisms of LER generation by simulating dynamics of polymer molecules in NTD using a meso-scale simulation technique called Dissipative Particle Dynamics (DPD). In DPD method, several neighboring monomers in a polymer chain are represented by one DPD particle with soft interaction potentials to accelerate calculation of polymer dynamics. In our previous studies, we performed virtual lithography experiments to study the molecular level polymer configuration, and investigated the polymer dissolution rate and the resulting LER generation. In the current work, in order to make this simulation method more practical for resist polymer design, we develop a method to tune the model parameters by calibrating to the experimental data obtained by development of actual resist polymers.