Diverse Responses in Lattice Thermal Conductivity of n-Type/p-Type Wurtzite Semiconductors Driven by Asymmetric Electron-Phonon Interactions.

Abstract

Accurately assessing the impact of electron-phonon interaction (EPI) on the lattice thermal conductivity of wurtzite semiconductors is crucial for the thermal management of electronic devices, and a unified physical understanding of this issue is highly desired. In this work, the lattice thermal conductivities of typical direct and indirect bandgap wurtzite semiconductors are predicted, accounting for EPI based on mode-level first-principles calculations. It is found that there exist diverse responses in the lattice thermal conductivity of n-type/p-type wurtzite semiconductors concerning charge carrier concentrations due to asymmetric EPIs. The EPI has a larger effect on the lattice thermal conductivity of p-type doping compared to n-type doping in the same wurtzite semiconductor. The stronger EPI in p-type doping is attributed to the relatively higher electron density of states caused by the p-orbital component. Furthermore, EPI has a stronger influence on the lattice thermal conductivity of n-type indirect bandgap wurtzite semiconductors than n-type direct bandgap wurtzite semiconductors. This is attributed to the relatively lower electron density of states in direct bandgap wurtzite semiconductors stemming from the s-orbital component.