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Metalorganic molecular beam epitaxial (MOMBE) growth of ZnSe and ZnS has been demonstrated and characterized. Diethylzinc and diethylselenide were used for the ZnSe growth, whereas both hydrogen sulphide and diethylsulphide were tested as sulphur sources for the ZnS growth. When group VI alkyls were used as sources, pyrolysis in a cracking cell was required. Quadrupole mass analysis of the DEZ, DESe, and DES was performed to clarify the growth mechanism. Smooth, monocrystalline ZnSe layers could be grown on GaAs(100) at substrate temperatures above 200°C. Photoluminescence spectra of ZnSe layers measured at 4.2K showed resolved exciton emissions. However, donor-acceptor pair emission lines attributed to a Li acceptor (Liza) were also observed. Smooth, monocrystalline ZnS layers could be grown on GaAs(100) at substrate temperatures above 250°C by using cracked H2S and DES, and above 150°c by using uncracked H2S. Photoluminescence spectra of ZnS layers at 74K were dominated by the blue emissions. Every ZnS layer grown on a GaAs(100), GaAs(111), or GaP(111) substrate exhibited a specular surface, streaky RHEED pattern, and blue luminescence. These good results reflect the complete absence of a premature reaction. Growth of a ZnSe-ZnS strained-layer superlattice on a GaAs(100) substrate was also demonstrated. Blue luminescence from the quantized levels in the ZnSe well layer was detected.
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