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Various fundamental characteristics of Y2O3 ceramics, such as optical transmittance, reflectivity, absorption coefficient, refractive index, and dielectric constant, were investigated. Furthermore, in order to evaluate the possible application of this material as γ-ray scintillator, other radiation responses, like the α-ray excited emission spectrum, the γ-ray excited pulse height spectrum, the light yield, the nonproportionality, the energy resolution, and the γ-ray excited scintillation decay curves were obtained. The light yield of Y2O3 ceramics was evaluated in about 1.13 times higher than that of Bi4Ge3O12(BGO):Ce single crystals and was estimated in 9300 photon/MeV. The nonproportionality measurements showed a good proportionality. The scintillation decay curve could be fitted by an exponential function characterized by a fast component of about 34 ns.

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Using the liquid phase epitaxy (LPE) method we prepared the high crystalline quality In 3+ doped ZnO thin film scintillators with different Indium concentration of 26, 53, and 141 ppm. We evaluated their optical properties and radiation response, because there are few reports of radiation response of In-doped ZnO scintillator. In order to imitate the scintillator application, we measured the alpha-ray excited luminescence spectra. The emission bands peaking around 375 and 500 nm were observed, and with an increment of In 3+ , the intensity of both bands decreases. In the measurement of light yield, we optically coupled the sample with PMT R7600 by a silicone grease, and excitation was provided by 241 Am 5.5 MeV -rays. The samples showed of about 10% of the light yield of BGO scintillator which was used as a reference. Under the same excitation the scintillation decay was measured in all the samples as well.

Present work describes the first detailed γ-ray light yield of Ce3+ perturbed emission in CaF2 host. (1-, 3-, 5-, 10-, and 20-mol %-) Ce3+-doped single crystalline CaF2 scintillator crystals were grown by the micro-pulling-down method. Their transmittances were measured to be approximately 80% at UV to visible wavelengths. All the crystals exhibited emission peaks at approximately 330 nm, which were identified as the Ce3+ perturbed emission, when they were irradiated by 1 GBq 137Cs. The photoluminescence decay kinetics was measured to be about 40 ns for all the crystals. Scintillation light yield in unit of photons/MeV (ph/MeV) was measured, and the 5% sample showed the highest light yield of around 900 ph/MeV with 2 µs shaping time.