Evidence for energy transfer between Eu3+ and Tb3+ in porous silicon matrix

Europium or terbium and europium have been incorporated into luminescent porous silicon (Eu3+/PS and (Eu3++Tb3+)/PS) by simple impregnation of PS layers with chloride solution of rare earth. This impregnation has been followed by Rutherford back-scattering spectrometry (RBS). The concentration dependency of photoluminescence (PL) intensity has been investigated. The excitation mechanisms of Eu3+ and Tb3+ ions in the PS matrix are discussed through the effect of excitation ray and the results of concentration dependencies of PL measurements. It was found that there is an efficient energy transfer from Tb3+ to Eu3+ and to Si nanocrystallites.