Optical characterization of porous silicon embedded with CdSe nanoparticles

Arrays of a few nanometer-size clusters have been realized using a porous silicon (PS) matrix by filling its pores with CdSe. The photoluminescence (PS) peak from the embedded area of the PS samples with different luminescence stabilizes at 1.79 eV. This has been interpreted as due to emission from the CdSe clusters with an average size of about 3-5 nm. Likewise, the PL and Raman scattering spectra of the pure PS area of the samples have been compared with those obtained from the embedded areas. PL spectra were examined as a function of laser irradiation. Finally, to analyze the possibility of the formation of metal/porous semiconductor contacts, cross-section structures have been observed by scanning electron microscopy in the electron-beam-induced current mode. (C) 1998 American Institute of Physics. [S0003-6951(98)00445-8].