Fabrication process dependency of dosimetric and scintillation properties of sapphire crystals

Dosimetric, and scintillation properties of undoped sapphire (Al₂O₃) single crystal fabricated by different methods of the Czochralski (Cz) and the Bridgman were investigated. In X-ray induced radioluminescence spectra, they showed emission peaks at 240 and 300 nm due to exciton and F⁺ centers, respectively. Scintillation decay times of F⁺ center was fast around few ns. As a dosimetric property, from 0.01 to 2 Gy X-ray was exposed to them and they exhibited a thermally stimulated luminescence (TSL) with a good linearity. The glow peaks of them were similar, 150, 250, and 325 °C. In TSL, the Bridgeman sample represented only F-center emission while the Cz sample showed F at 400 nm and F⁺ at 300 nm centers emission.