Solar-Blind UV Detectors Based on β-Ga 2 O 3 Films

Resistive-type structures based on gallium-oxide films are studied. The Ga 2 O 3 films are produced by radio-frequency magnetron-assisted sputtering of a β-Ga 2 O 3 (99.9999%) target onto unheated sapphire substrates with preliminarily deposited platinum electrodes. The data on the structure and phase composition of the films are obtained immediately after sputtering and after annealing in argon at 900°C for 30 min. The current–voltage characteristics are recorded in the dark and upon exposure to radiation at the wavelength λ = 254 nm. It is shown that, after annealing, the photocurrent increases by an order of magnitude. The lack of sensitivity of the structures to radiation in the visible wavelength region (λ = 400 nm) is verified experimentally.