Luminescent Er-doped films were prepared at room temperature by using a technique which involved magnetron deposition of an Er-doped Al film onto a Si substrate, and its subsequent electrochemical anodization. The films exhibited strong Er-related photoluminescence at about 1.53μm, for temperatures ranging from 4.2 to 300K. The effect was not altered by annealing at up to 200C. Upon annealing at 300 to 500C, the luminescence intensity decreased. Upon annealing at temperatures above 600C, it began to recover. Annealing at 1000C restored the photoluminescence spectra to their initial level. These annealing effects were explained in terms of H out-diffusion at 300 to 500C, to the rearrangement of point defects at 600 to 800C and to recrystallization above 850C. the activation energies of these processes were estimated to be 0.76eV (parabolic rate), 0.58eV (linear rate) and 0.46eV (linear rate), respectively.

Room-Temperature Formation of Erbium-Related Luminescent Centers in Anodic Alumina. S.K.Lazarouk, A.V.Mudryi, V.E.Borisenko: Applied Physics Letters, 1998, 73[16], 2272-4