Gallium Oxide Schottky Barrier Diodes

Abstract

The new wide-bandgap oxide semiconductor, gallium oxide (Ga₂O₃), has gained attraction as a promising candidate for power device applications because of its excellent material properties and suitability for mass production. Fundamental halide vapor phase epitaxy (HVPE) technology for Ga₂O₃ thin film growth has been developed for development of vertical Ga₂O₃ devices. Unintentionally-doped Ga₂O₃ layers grown by HVPE were high purity and high crystalline quality, and an electron density in the Ga₂O₃ film can be precisely controlled by Si doping in the wide range of n=10¹⁵-10¹⁸ cm^-3. We fabricated vertical Ga₂O₃ Schottky barrier diodes (SBDs) with HVPE-grown n^--Ga₂O₃ drift layers on single-crystal β-Ga₂O₃ (001) substrates. The SBDs demonstrated promising device performance as next-generation power devices, such as the specific on-resistances of about 3.0 mΩ·cm², the ideality factors of almost equal to unity, and the off-state breakdown voltage of about -500 V.