The present work is concerned with Er-doped oxidized porous silicon (PS). The characteristic feature of the work is that PS doping has been realized by an electrochemical procedure followed by a high temperature treatment. 5-#mu#m thick PS layers were formed on p-types Si of 0.3-Ohm.cm resistivity. Er incorporation was performed by a cathodic polarization of PS in a 0.1M Er(NO_3)_3 aqueous solution. A high temperature treatment in an oxidizing ambient at 500-1000deg C was utilized to provide either partial or total oxidation of PS:Er layers. X-ray microanalysis was used to study chemical composition of the samples. Photoluminescence (PL) and photoluminescence excitation (PLE) spectra were investigated. After the partial oxidation (in the temperature range of 600-800deg C), weak Er~(3+) -related PL at 1.53 #mu#m was observed. A high temperature anneal in Ar atmosphere at the temperature of 1100 deg C caused a significant increase in the Er~(3+)-related PL intensity. Resonant features were observed in PLE spectra of fully oxidized PS. Five peaks at 381, 492, 523, 654, and 980 nm were revealed. The strongest excitation occurred at 381 and 523 nm. The excitation of different Er~(3+) energy levels, cross-relaxation interactions and emission due to the ~4I_(13/2)->~4I_(15/2) transitions were considered. Application of the Er-doped oxidized PS for integrated optical waveguides is presented.
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