Ab initio study on phonon-limited electron mobility of strained ZnO with self-consistent Hubbard interactions

Electron mobility and optical absorption are key functional properties of semiconducting materials. Recent advances in computational methods have extended density-functional perturbation theory (DFPT) by incorporating the Hubbard interaction U, thereby enhancing the accuracy of calculations involving electron–phonon interactions. In this talk, we employ a DFPT+U approach with a self-consistent Hubbard interaction to evaluate the phonon-related properties of strained zinc oxide (ZnO). ZnO is a wide-band-gap oxide semiconductor broadly utilized in electronic and optoelectronic devices, such as transparent and flexible displays, where mechanical strain often plays a crucial role. We compute phonon-limited electron mobility and optical absorption of strained ZnO, both of which influence display performance. With increasing strain up to 5% along the [\bar{1}10] direction, the electron mobility at room temperature is found to increase up to 19% while the optical absorption for visible range is almost intact. These results demonstrate the potential of computation-driven strain-engineering strategies for optimizing carrier mobility and optical properties in oxide semiconductors without relying on empirical parameters.