Energy transfer mechanism between terbium and europium ions in zinc oxide and zinc silicates thin films
Résumé
The aim of this study is to enhance europium ions emission by energy transfer mechanism from terbium to europiumions
in codoped ZnO thin films. The samples were annealedwith classical and rapid thermal anneal treatments
for different temperatures (973 K, 1173 K and 1373 K). Codoped ZnO thin films were characterized for
their chemical, structural and photoluminescence properties. Two different terbium concentrations have been
studied with roughly constant europium content. Terbium and europium codoping allows an energy transfer
from trivalent terbium to europium ions leading to the europium emission hardly observed for ZnO thin films
doped by europium only. With thermal annealing above 1173 K, diffusion processes occurred with silicon substrate
to form zinc silicate and rare earth oxide with a concomitant photoluminescence signal from trivalent europium
ions at 615 nm (5D0 → 7F2 transition).