Scintillation Response Comparison Among Ce-Doped Aluminum Garnets, Perovskites and Orthosilicates

This paper deals with some aspects of scintillation response of Ce-doped Y-Lu aluminum garnets or perovskites in comparison with Ce-doped orthosilicates. An essential difference between the Ce-doped aluminum garnets/perovskites and orthosilicates consists in larger fluctuations of photoelectron yield of the latter scintillators where differences can reach up to 50% and measured values critically depend on the recent history of the sample (illumination by day light, thermal annealing, etc.). This behavior of Ce-doped silicates seems to be due to the vicinity of the 5d₁ level of Ce³⁺ from the conduction band, which makes the material more sensitive to the presence of deep electron traps monitored by thermo-luminescence above room temperature. The presence of such electron trapping sites thus appears more critical than in aluminum garnets/perovskites.