Progress in atomic layer deposited [alpha]-Ga2O3 materials and solar-blind detectors

Atomic layer deposition (ALD) offers a low thermal budget method for producing α-Ga₂O₃ films on sapphire substrate. In this paper we review the recent progress on plasma-enhanced ALD growth of α-Ga₂O₃ and present the optical and photoconductive properties of the deposited films. We show that the deposited material exhibits an epitaxial relationship with the sapphire substrate, and with an atomically sharp film-substrate interface. The α-Ga₂O₃ films had an optical bandgap energy measured at 5.11 eV, and exhibited a broad luminescence spectrum dominated by ultraviolet, blue and green bands, in line with current literature. We finally demonstrate the suitability of the material for solar-blind photodetection.