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We have recently reported the growth of ZnTe and CdTe thin films from the novel volatile single-source precursors Zn(sitel)2 and Cd(sitel)2 [sitel = TeSi(TeSi(siMe3)3]. In an effort to understand the role played by the bulky substituents, we have prepared a number of related compounds and have investigated their potential for the growth of II-VI materials. We now describe the synthesis and characterization of M[EX(SiMe3)3]2 (M = Zn, Cd, Hg for E = Te, X = C; M = Zn for E = Se, X = C, Si) and their use as precursors molecules for the growth of ZnSe, ZnTe, CdTe and HgTe. The thin films were characterized by Rutherford Back scattering spectrometry (RBS) and X-ray diffraction. Pyrolysis reaction conditions for the alkyl and silyl chalcogenolates are also compared.

Isotopically pure 74 Ge nanocrystals were formed in a sapphire matrix by the ion beam synthesis method. In contrast to those embedded in amorphous silica, sapphire-embedded nanocrystals are clearly faceted and are preferentially oriented with respect to the crystalline matrix. In situ transmission electron microscopy of heated samples reveals that the nanocrystals melt at 955 °C ± 15 °C, very near to the bulk Ge melting point. Raman spectra indicate that the sapphireembedded Ge nanocrystals are under compressive stress in the range of 3 -4 GPa. The 2 magnitude of the stress is consistent with that expected for hydrostatic pressure arising from solidification. Stress relaxation was not observed for sapphire-embedded Ge nanocrystals; this is attributed to the slow self-diffusion rate of the alumina matrix atoms at temperatures below the nanocrystal melting point.