Phonon-Limited Mobility in n-Type Few-Layer InSe Devices From First Principles

A theoretical investigation on the phonon-limited mobility in intrinsic n-type few-layer indium selenide (InSe) double-gate devices for temperature T > 100 K is presented. The temperature-dependent mobility curves measured by quantum Hall effect are reproduced successfully by invoking the scatterings by acoustic phonon, homopolar optical phonon, longitudinal optical phonon via the deformation potential coupling, and the Fröhlich interaction. In InSe, the Fröhlich interaction plays the dominant role in determining the mobility. Additionally, simulated thickness-dependent mobility provides physical insight into the mobility degradation below 30 nm.