| Summary: | 碩士 === 中原大學 === 電子工程研究所 === 101 === I-II-VI ternary chalcopyrite semiconductors of Cu1-xZn1-ySe2-δ(Cu-Zn-Se) were successfully fabricated by atmospheric pressure metal-organic
chemical vapor deposition method for the first time. Four major peaks of (112),(220)/(204), (312)/(116), and (400), accompanied by three minor peaks of (103),(211) and (301) were observable in the X-ray diffraction spectra. In particular,the presence of those latter low-intensity peaks featured the formation of the
chalcopyrite type Cu-Zn-Se compound. Typical absorption coefficients of the films produced were found to be higher than 3x104 cm-1 over all visible light range and from the same optical absorption spectra the energy gap of the
material was extracted to be 2.02 eV. Moreover, the photoluminescence measurement conducted at room temperature also exhibited a strong
orange-colored emission line at 1.94 eV, which further confirmed that the Cu-Zn-Se ternary compound has been prepared. In addition, the cross-sectional and top-view scanning electron microscopy images characterized the fabricated
Cu-Zn-Se compound as a polycrystalline film of thickness about 1 – 1.3μm and consisting of 1 - 2.5μm sized grains. We were used the transmission electron microscopy (TEM) to recognized the boundary condition of the grain Cu-Zn-Se and combined the Energy Dispersive Spectrometer (EDS) to analysis the stoichiometric of grain Cu-Zn-Se. A focused-ion-beam (FIB) microsampling technique was used for preparing cross-sectional TEM specimens from a TEM specimen. In addition, the cross-sectional of TEM images characterized the fabricated compound as a polycrystalline film of about 70-80nm thick. The chalcopyrite structure of CZSe is set up from TEM. The chemical composition of CZSe is about Cu:Zn:(Se+O)=0.92:1.44:2.
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