Thermal Resistance of Semiconductor Thin Films Predicted From Lattice Dynamics Calculations and Molecular Dynamics Simulations

Semiconductor thin films are pervasive in advanced technological devices. For example, the active region in a quantum cascade laser contains films of direct bandgap semiconductors with thicknesses of 1–10 nm [1]. Superlattices, periodic materials that contain films of alternating species with thicknesses as small as 1 nm, are being studied for their potential to increase the efficiency of thermoelectric energy conversion devices [2]. Because these film thicknesses are less than the mean free paths of the phonons in the corresponding bulk material, the thermal transport properties of semiconductor thin films are different than their corresponding bulk values [3]. To aid in the design of devices employing thin films, accurate models for the thermal transport properties of the film are required.