Controlling different phases of gallium oxide for solar-blind photodetector application

Ultra-wide bandgap semiconductor gallium oxide (Ga2O3) exhibits high resistance to electrical stress, temperature, and radiation, and is now attracting increasing attention for power electronics and optoelectronics applications. So far, different phases of Ga2O3, including amorphous, polycrystal, and single crystal (α, β, γ, δ, ɛ, and κ), have been reported and their bandgaps fall in the range from 4.4 to 5.3 eV which is suitable for deep ultraviolet (DUV) solar-blind photodetection (SBPD). In this chapter, we focus on the recent advances in achieving high quality Ga2O3 materials with different phases for SBPDs application. First of all, the growth of different phases of Ga2O3 films are summarized, including the synthesis of bulk β-phase Ga2O3 and the epitaxy of different Ga2O3 polymorphs by various growth tools. Secondly, we present the-state-of-art SBPDs based on different phases as well as their detailed device characteristics. Lastly, the emerging Ga2O3 SBPDs with various device architectures are also discussed. In short, the development of Ga2O3 materials as well as their implementation for SBPDs have raised great of interest in the semiconductor community for solar-blind detection, imaging, and advanced optical communication technologies of the future.