A New Elaboration Route by Sol-Gel Process for Cerium Doped SrHfO3Films and Powders

Abstract

We present for the first time the elaboration via sol gel route of cerium (1 mol%) doped SrHfO3 powders and films. The sol is elaborated using hafnium and strontium ethoxides as precursors and cerium nitrate as dopant. The structure of powders and films are characterized by convergent methods: Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, Raman spectroscopy and optical measurements conducted by the prism coupling method. The powder crystallises from amorphous to pure SrHfO3 orthorhombic perovskite phase after a 800°C heat treatment. Nevertheless HfO2 monoclinic phase coexists with orthorhombic perovskite phase after a 1000°C heat treatment. The film is amorphous for annealing temperatures lower than 700°C and presents good waveguiding performances. The film heat-treated at 700°C exhibits a refractive index of 1.810 ± 0.001 (λ = 543.5 nm) for a thickness around 375 nm. The attenuation coefficient obtained on the 400°C heat-treated film is α = 4.0 ± 0.5 dB/cm (λ = 632.8 nm). The film starts to crystallize at 750°C into the SrHfO3 orthorhombic phase but HfO2 monoclinic phase is also detected after a heat treatment at 1000°C. The potentiality of sol gel Ce3+:SrHfO3 powders and films for scintillation applications are investigated.