SIMULATIONS OF HYDROGEN DEPOSITION PROCESSES IN A-SIH FILM GROWTH

Molecular dynamics simulations of the deposition of atomic H on both c-Si and a-Si:H substrates are performed to understand the physical processes occurring in the presence of an atomic H flux during growth. The absorption probability, and dynamical behavior of the H are studied as a function of the incident H energy. Both hydrogen absorption and backscattering events are observed. The hydrogen reflection probability has a maximum around 50 eV and decreases at higher incident kinetic energies. In the hydrogen backscattering events a substantial subsurface penetration and energy transfer through collisions are observed. Hydrogen absorption events have been closely analyzed and a surface hydrogen release event was observed during an absorption event.