High performance gate tunable solar blind ultraviolet phototransistors based on amorphous Ga 2 O 3 films grown by mist chemical vapor deposition

Abstract

Gallium Oxide (Ga 2 O 3 ) for solar‐blind photodetectors (PDs) has drawing increasing research interest in recent years because of its natural wide bandgap. However, the traditional material growth methods are always complicated and the corresponding PD performance is also not good enough. In this work, amorphous Ga 2 O 3 (a‐Ga 2 O 3 ) thin film grown by mist chemical deposition applied as solar blind deep ultraviolet phototransistors (PTs) is investigated for the first time, to solve the problem of high cost and time‐consuming by traditional methods. Bottom‐gate a‐Ga 2 O 3 three terminal thin film transistors (TFTs) are fabricated to boost their ultraviolet (UV) photodetection properties. Under the 254 nm UV illumination, the a‐Ga 2 O 3 PTs demonstrates a very high responsivity of 2300 AW −1 , external quantum efficiency of 1.12 × 10 6 % and detectivity of 1.87 × 10 14 Jones. Such field‐effect PTs with the ultrahigh performance address a significant step toward the feasibility and practicability of Ga 2 O 3 PDs in the future applications.