Simultaneously high electron and hole mobilities in cubic boron-V compounds: BP, BAs and BSb

TL;DR

This study uses first-principles calculations to reveal that cubic boron-V compounds like BAs exhibit high electron and hole mobilities due to suppressed phonon scattering, making them promising for electronic applications.

Contribution

It demonstrates that BAs has both high electron and hole mobilities at room temperature, a rare combination in semiconductors, due to its high optical phonon frequency.

Findings

BAs has high hole mobility (2110 cm2/V-s)

BAs has high electron mobility (1400 cm2/V-s)

High optical phonon frequency suppresses polar scattering

Abstract

Through first-principles calculations, the phonon-limited transport properties of cubic boron-V compounds (BP, BAs and BSb) are studied. We find that the high optical phonon frequency in these compounds leads to the substantial suppression of polar scattering and the reduction of inter-valley transition mediated by large-wavevector optical phonons, both of which significantly facilitate charge transport. We also discover that BAs simultaneously has a high hole mobility (2110 cm2/V-s) and electron mobility (1400 cm2/V-s) at room temperature, which is rare in semiconductors. Our findings present a new insight in searching high mobility polar semiconductors, and point to BAs as a promising material for electronic and photovoltaic devices in addition to its predicted high thermal conductivity.