Ce-doped Ga2O3 single crystalline semiconductor showing scintillation features

We synthesized Ga2O3 crystals doped with 0.04, 0.61, 0.87 and 1.9% of Ce by the Floating Zone (FZ) method and measured the optical and scintillation properties systematically. All the Ce-doped Ga2O3 samples showed emission peaking around 420 nm in the X-ray induced scintillation as well as photoluminescence spectra under 280 nm excitation, and the origin of this emission was attributed to the 5d-4f transitions of Ce3+. The scintillation decay curves were approximated by a sum of three exponential decay functions, and the decay time constants ranged tens of nanoseconds, corresponding to the emission by Ce3+, and a few or hundreds nanoseconds, corresponding to the Ga2O3 host. The Ce-doped Ga2O3 samples also showed thermally-stimulated luminescence (TSL) after 10 Gy X-ray irradiation with the glow peak around 140 °C, and the TSL intensity increased with increasing the doping concentration of Ce.