ε-Ga2O3 epilayers as a material for solar-blind UV photodetectors

Electrical and optical properties of undoped single-phase ε-Ga2O3 epitaxial films prepared by MOCVD are reported. It is shown that this still unexplored polymorph of gallium oxide possesses wide bandgap and very high dark resistivity, thus allowing the design and fabrication of solar-blind UV photodetectors. Simple cost-effective photoresistors, fabricated by direct deposition of the epilayers on c-oriented sapphire substrates, exhibited good performance. The physical properties and the photoresponse of ε-Ga2O3 make this material very interesting in view of novel applications.