Preparation and broadband white emission of Eu-doped thin films based on SiAlON

Abstract The optical performance of europium (Eu) doped SiAlON thin films and its preparation by pulsed laser deposition are studied. The undoped SiAlON films show a high refractive index (2.34) close to that of silicon nitride. After doping with Eu the oxygen content increases in the films and leads to the formation of an oxynitride with a refractive index of 1.87 and excellent transparency in the visible-near infrared. Upon excitation at 355 nm the films show a broad band (FWHM of 200 nm) emission in the visible range (400–750 nm) that is associated to the emission of the Eu in the 2+ oxidation state. Enhancement of the emission together with a blue spectral shift has been found when the films are annealed at low temperature (600 °C). These films show promising properties for the development of Si compatible thin films integrated emitters.