We show how Raman optic-mode peak positions and relative intensities can be used in a straightforward way to determine crystallite composition in CdSxSe1−x nanocrystals embedded in glass. These Raman techniques are particularly useful for low-concentration or small-crystallite-size composites where x-ray diffraction is not a viable technique for structural characterization of crystallites.

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We review structural and optical properties of CdSxSe1−x semiconductor nanoparticles embedded in an insulating glass matrix. Vibrational Raman scattering and x-ray diffraction can be used to determine the composition of the crystallites for all X and sizes. Debye-Scherrer broadening of x-ray diffraction peaks from the crystallites yields an average grain size in the semiconductor crystallites of 60Å for the series studied here. Small angle x-ray scattering reveals that the average particle diameter is close to 120Å. Optical absorption, photoluminescence, and photomodulated absorption spectra are interpreted within a spherical quantum well model. Electron-phonon coupling and size distribution effects on the spectra are also discussed.

Ga doped ZnO (GZO) films were prepared by radio frequency (rf) magnetron sputtering on glass or silicon substrates. Electrical, optical, and structural properties of these films were analyzed in order to investigate their dependence on thermal annealing temperature. GZO films with a minimum resistivity of 5.2×10-3 Ω-cm annealed at 400°C and a transparency above 80% in visible region were observed. The temperature-dependent conductivity affected the carrier transport and was related to the localization of carriers. The results of transmission spectra were consistent with the results of atomic force microscopy (AFM) scan. X-ray diffraction analysis and electron spectroscopy for chemical analysis were also used to investigate the properties of GZO films.

We shall report the results of structural and optical studies of semiconductor microparticle composites consisting of small (<20nm) CdS x Se1− x crystallites embedded in a glassy matrix1. Recent studies2–4 have shown this class of materials to have large third-order optical susceptibility with fast response time (< 20ps), therefore it is of great interest for nonlinear optical applications. Before we can assess the fundamental limitations and ultimate promise for these materials it is necessary to increase the base of information relating optical and electronic properties to structural properties such as crystal size, strain, defects, and composition. Surprisingly little work has been published in this area5,6.