Insulator-to-semiconductor conversion of solution-processed ultra-wide bandgap amorphous gallium oxide via hydrogen annealing

Abstract

Abstract Developing semiconducting solution-processed ultra-wide bandgap amorphous oxide semiconductor is an emerging area of research interest. However, obtaining electrical conduction on it is quite challenging. Here, we demonstrate the insulator-to-semiconductor conversion of solution-processed a-Ga2O x (E g ∼ 4.8 eV) through hydrogen annealing. The successful conversion was reflected by the switching thin-film transistor with saturation mobility of 10−2 cm2 V−1s−1. We showed that H incorporated after hydrogen annealing acts as a shallow donor which increased the carrier concentration and shifted the Fermi level (E F) closer to the conduction band minimum.