Blue photoluminescence in ZnGa2O4 thin-film phosphors

Abstract

The growth and properties of luminescent ZnGa2O4 thin films using pulsed laser ablation has been investigated. As-deposited films on glass and (100) MgO substrates exhibit blue-white photoluminescence with a broad emission band under ultraviolet excitation. In situ epitaxial films obtained on single crystal (100) MgO substrates possess enhanced luminescent intensity as compared to polycrystalline films on glass substrates. The enhanced luminescence in epitaxial films presumably reflects lower defect densities due to growth on low energy surfaces.