Er rare-earth ion incorporation in sol-gel SnO2

Abstract

Er-doped SnO2 thin films and xerogels are obtained by sol-gel technique. In order to understand the Er³+ rare-earth ion activity in SnO2 matrix, a characterization of Er incorporation is done through emission and excitation spectra of xerogels, besides thin film electrical characterization. Effects to grain dimensions are also analyzed based on X-ray diffraction data showing the particle growth with annealing temperature and inhibition of this growth by Er doping. Electrical characterization results suggest that Er³+ has an acceptor-like character in SnO2, and that codoping with Yb³+ allows an energy transfer process Yb³+ -> Er³+

Visible emission from Er-doped SnO2 thin films deposited by sol-gel

“…2, where a typical result for undoped film is shown in wavelength (nm) luminescence the inset. The grain size evaluated from these data, based on Scherrer equation [18] is 3.5 nm for the doped film and 6.0 nm for the undoped film, showing that the doping procedure also inhibits the grain growth [19]. At this point it must be mentioned that the crystallite size in the Er-doped SnO 2 thin film may play a very important role concerning the quantum confinement effects by nanocrystals.…”