Templated growth of textured and luminescent CaS : Eu thin films by a low-temperature solvothermal process

Abstract

The direct growth of luminescent sulfide thin films onto templated substrates was realized with a solvothermal synthesis method. The as-grown layers of SrS : Eu and CaS : Eu emit a bright and homogeneous photoluminescence, peaking at 610 nm and 650 nm, respectively. X-ray diffraction measurements showed that the layers grown at a temperature of only 200 °C are strongly crystalline, with (2 0 0) out-of-plane orientation. Using silicon substrates, almost epitaxial growth could be obtained. Electron microscopy was used to study the growth, morphology and texture of the thin films. The main advantages of this innovative approach for the production of sulfide layers are the low-temperature process and scalability.