Monte Carlo Simulations of Thermal Conductivity in Nanoporous Si Membranes

We present a Monte Carlo study of heat transport in Si nanomeshes. Phonons are treated semiclassically as particles of specific energy and velocity that undergo phonon-phonon scattering and boundary scattering on the surfaces of the nanomesh pores. We investigate the influence of: (1) geometric parameters such as the pore arrangement/randomness and porosity, and (2) the roughness amplitude of the pore surfaces on the thermal conductivity of the nanomeshes. We show that the nanomesh porosity has a strong detrimental influence on the thermal conductivity. Boundary roughness still degrades the thermal conductivity, but its influence is smaller