1.5µm light emission of Er3+ions doped in SiO2films including Si nanocrystallites and in SiOxfilms

We have investigated the fabrication of two types of Er-doped silicon oxide films. The films were prepared by ablating a Si target covered with a thin Er metal layer, by Nd:YAG laser light at 50 mJ/pulse in 40 Torr O2 gas. After depositing the Er-dispersed SiOx (x ~ 1.4) films, the films were annealed in Ar gas. We found that Er-doped films deposited at (a) 4 J/cm2 and (b) 100 J/cm2 have the optimum annealing temperatures of 600°C and 900°C, respectively. Furthermore, we found that Er-doped films deposited at 4 J/cm2 exhibit much more intense light emission at 1.5 µm than those deposited at 100 J/cm2. For the Er-doped films deposited at 100 J/cm2, it is evident that electron-hole pairs are generated in Si nanocrystallites precipitated in a SiO2 film and that recombination energy is transfered to Er3+ ions that emit 1.5 µm light, via the lowest luminescent state in Si nanocrystallites.