PREPARATION OF CDS-DOPED GLASSES FROM GELS CONTAINING DIETHYLDITHIOCARBAMATOCADMIUM

CdS-doped SiO2 glasses were prepared via silica gels containing diethy ldithiocarbamatocadmium Cd(S2CN(C2H5)(2))(2). Heat treatment of the ge ls gave transparent yellow SiO2 glasses doped with hexagonal CdS cryst als. In optical absorption and fluorescence spectra, the optical absor ption edge and the emission peak clearly exhibited a blue shift, which was attributed to the quantum size effect of the carrier confinement, as the CdS content was decreased. In the fluorescence spectra of the CdS-doped silica glasses, the emission peak was observed only near 500 nm and not observed at longer wavelengths which were known to be pres ent if there were sulfur vacancies.