Modeling of ECR plasma discharges in hydrogen with an electromagnetic PIC code

Hydrogen gas used in EUV lithography machines becomes ionized by the EUV radiation and creates a plasma environment, which can significantly interact with the surrounding walls and optical elements. However, due to high operation costs direct experimental investigations of the hydrogen plasmas in such machines are difficult. Instead, one can create and study plasmas with comparable characteristics in more accessible devices, e.g., using an electron-cyclotron-resonance (ECR) plasma source. The present work reports modeling of the ECR plasmas produced in a low-pressure hydrogen gas.To take into account kinetic and nonlocal effects, an energy- and charge-conserving implicit electromagnetic particle-in-cell (PIC) code ECCOPIC2M-M is used, combined with kinetically described atomic and molecular hydrogen species. The numerical model is enhanced with the adaptive particle management and time-slicing methods. Validation of simulation results with previously obtained experimental data is addressed.