Strain Engineering of GaN for Hole Mobility Optimization: A comprehensive approach*

Gallium nitride (GaN) is a versatile wide-band gap semiconductor vital for applications in power electronics, radio-frequency devices, and rapid switching transistors. However, its p-channel devices face a challenge due to low hole mobility, obstructing its integration into next-generation technologies. Various strain states have been explored individually to enhance hole mobility, but a comprehensive assessment of their collective impact is lacking. In this study, we establish a linear tensor equation that correlates hole mobility and applied strain in GaN. Our approach leverages ab initio Boltzmann transport equations, accounting for electron-phonon scattering and quasiparticle energy corrections to derive hole mobilities. We use this knowledge to identify a set of optimal strain conditions, maximizing GaN hole mobility. Moreover, our methodology offers a general framework for first-principles-based material property engineering through strain manipulation.