Ce3+:CaHfO3 thick film scintillators epitaxially grown on SrTiO3, YAlO3, and MgO substrates using chemical vapor deposition

Abstract

Alkaline earth hafnate perovskite is a promising inorganic scintillator due to its high density and high stopping power; however, its high melting point and phase transitions at elevated temperatures make its crystal growth difficult. We apply chemical vapor deposition method to prepare Ce³⁺-doped CaHfO₃ (Ce³⁺:CaHfO₃) thick films on the SrTiO₃, YAlO₃, and MgO substrates. Ce³⁺:CaHfO₃ thick films were epitaxially grown on each substrate with deposition rates of 44–77 μm h⁻¹. The luminescence spectra of the films at the excitation wavelength of 340 nm showed peaks at 423 nm and 463 nm, which were attributed to the Ce³⁺ 5d → ²F_5/2 and 5d → ²F_7/2 transitions, respectively. The scintillation light yield of the Ce³⁺:CaHfO₃ thick film grown on the MgO substrate was 2900 photons per 5.5 MeV with fast decay constant of 32.1 ns.