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Heteroepitaxial InP layers were grown on Si(111) by metalorganic vapor phase epitaxy using thermal cycle growth. The best crystallographic and optical quality was obtained when thermal cycle growth was begun after only a thin InP layer had been deposited. High resolution x-ray diffraction rocking curves of 4.8 μm thick InP layers yield full widths at half-maximum as low as 76 arc s and show that epilayers have a positive tilt with respect to the substrate. Cross-section transmission electron microscopy observations and Rutherford backscattering measurements show that thermal cycling induces a net reduction of defect density in the interfacial region. Photoluminescence (PL) measurements performed on the best quality thermal cycle grown sample show a thermal strain induced energy splitting of 3.8 meV between the free exciton emissions associated with heavy and light holes. Two other peaks in the PL spectra correspond to acceptor-bound (A0,X)mj=±3/2 and (A0,X)mj=±1/2 excitonic transitions, as confirmed by photoluminescence excitation measurements. Their full width at half-maxima are 1.4 and 0.9 meV, respectively, for the optimized samples. They may be associated with Si acting as an acceptor.

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The decay of 120Sbg and 120Sbm was studied with a 33 cm3 Ge(Li) detector and a multichannel analyzer. Through the use of coincidence techniques, excited states of 120Sn were established at 1171.0, 1874.2, 2159.2, 2193.8, 2282.9, and 2479.6 keV. The results are compared to existing decay schemes for 120Sbg,m and the theoretical predictions of contemporary nuclear models.