An Accurate and Transferable ReaxFF Parameter Set toward the Simulation of a Plasma Etching Process in Semiconductor Manufacturing

The plasma etching mechanisms of silicon- and carbon-based materials using fluorine atoms are significant for guiding the semiconductor manufacturing processes; however, the fundamental studies are hindered by the difficulty of experimentally measuring what happens in the etching process at the atomic scale. Although reactive molecular dynamics simulation is a strong tool to study the reaction dynamics of a plasma etching process, there are still no available reactive potentials to study the fluorine-etching process. In this work, we developed a suite of accurate and transferable reactive force field (ReaxFF) parameter set for the C/H/O/Si/F systems, by using a multiobjective global optimization strategy combining the simulated annealing algorithm (SA) and particle swarm optimization (PSO) algorithms. Besides, we demonstrated that the developed ReaxFF parameter set is very precise and valid for describing various properties, including the reaction dynamics of F-containing small molecules, gas–liquid transition, and the F-etching process of various silicon/carbon-containing solids. The above findings indicate that the developed ReaxFF parameters can accurately describe the reactions and phenomena involving C/H/O/Si/F elements, which is expected to contribute greatly to future research endeavors on the etching process.