Effect of preliminary oxidation annealing on properties of porous silicon impregnated with a tungsten-tellurite glass activated by Er and Yb

The effect of preliminary oxidation annealing of porous silicon (PS) on photoluminescence (PL) under laser pumping at wavelengths of 532 and 980 nm, EPR, and transverse current transport in structures based on PS with a fused tungsten-tellurium glass (TTG) doped with Er and Yb has been studied. It has been shown that such annealing and the presence of silicon nanocrystals ($nc$-Si) in PS promote multiple PL enhancement for both Er ions in TTG and $nc$-Si in PS at wavelengths of 750 and 1540 nm, respectively. As TTG is fused into PS, Pb-centers of nonradiative recombination are suppressed, while retaining discrete electron tunneling through $nc$-Si grains in PS.