【International Papers】Effect of Traps on the UV Sensitivity of Gallium Oxide-Based Structures

      Researchers from the National Research Tomsk State University have published a dissertation titled " Effect of Traps on the UV Sensitivity of Gallium Oxide-Based Structures " in Crystals.

Abstract

      Resistive metal/β-Ga₂O₃/metal structures with different interelectrode distances and electrode topologies were investigated. The oxide films were deposited by radio-frequency magnetron sputtering of a Ga₂O₃ (99.999%) target onto an unheated sapphire c-plane substrate (0001) in an Ar/O₂ gas mixture. The films are sensitive to ultraviolet radiation with wavelength λ = 254. Structures with interdigital electrode topology have pronounced persistent conductivity. It is shown that the magnitude of responsivity, response time τ_r, and recovery time τ_d are determined by the concentration of free holes p involved in recombination processes. For the first time, it is proposed to consider hole trapping both by surface states N_ts at the metal/Ga₂O₃ interface and by traps in the bulk of the film.

Figure 1. Schematic representation of detectors with two parallel electrodes (a) and detectors with interdigitated electrodes (b).

Figure 2. XRD pattern of gallium oxide film without annealing and annealed at 900 °C.

Figure 3. Survey PE spectra of the RFMS-deposited β-Ga₂O₃ film, measured before and after 300 s etching with argon ions.

Paper Link：https://doi.org/10.3390/cryst14030268