The photoluminescence characterization of rare earths (Tb, Gd) embedded into por ous silicon

Rare earth (Tb,Gd) ions were embedded into porous silicon films by electrochemical method. Fluorescence photospectrometer and scanning electron microscope were employed to characterize the photoluminescence and surface morphology of samples. The distribution of rare earth ions embedded into porous silicon films was observed by Rutherford backscattering spectrometry. The luminescence intensity of porous silicon after doping is greatly increased. Blue shift of luminescence peak was observed also. It is attributed to the transition luminescence of transitions between 4f energy levels of Tb3+, such as 5D4 —7F35D4—7F2 and 5D 4—5F0. Intense blue luminescence was observed after doping with Gd. The luminescence mechanism of porous silicon doped with rare earths was discussed also.