| Summary: | 碩士 === 中原大學 === 應用物理研究所 === 90 === Zn1-xMnxSe epilayers were grown on the GaAs (001) substrates by the molecular beam epitaxy (MBE). Optical properties were studied by the reflectance (R) and photoluminescence (PL) spectroscopy. The temperature dependence of the energy gap, measured by the PL spectra, was fitted by the Varshni’s and O’Donnell’s model. The phonon energy related fitting parameters β (113K to 306K) and <hν> (7meV to 10meV) were obtained from the Varshni’s and O’Donnell’s fits, respectively. Activation energies calculated from the Arrhenius’ plot of the integrated PL show a decrease with the Mn composition. The PL line-width broadening with the temperature was fitted by Γ(T)= Γ0+ΓaT+ΓLO1/[exp( LO1/kT)-1]+
ΓLO2/[exp( LO2/kT)-1]+Γiexp(-<Eb>/kT).
In addition to the study of Zn1-xMnxSe epilayers, the ZnTe quantum dots (QDs) were grown in the diluted magnetic semiconductor, Zn0.96Mn0.04Se, matrix on the GaAs substrate by molecular beam epitaxy. The averaged coverage of ZnTe was 1.7 ML, 2.0 ML, 2.3 ML, 2.7 ML, 3.0 ML, and 3.3 ML. The PL peak appears at energy between 2.15 eV and 2.41 eV is attributed to the radiation from ZnTe QDs. While, the peak at energy between 1.9 eV and 2.0 eV is due to emission from the intra-Mn2+ of Zn0.96Mn0.04Se.
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