STRUCTURAL AND OPTICAL CHARACTERIZATION OF INP GROWN ON SI(111) BY METALORGANIC VAPOR-PHASE EPITAXY USING THERMAL CYCLE GROWTH

Heteroepitaxial InP layers were grown on Si(111) by metalorganic vapor phase epitaxy using thermal cycle growth. The best crystallographic a nd optical quality was obtained when thermal cycle growth was begun af ter only a thin InP layer had been deposited. High resolution x-ray di ffraction rocking curves of 4.8 mu thick InP layers yield full widths at half-maximum as low as 76 arc s and show that epilayers have a posi tive tilt with respect to the substrate. Cross-section transmission el ectron microscopy observations and Rutherford backscattering measureme nts show that thermal cycling induces a net reduction of defect densit y in the interfacial region. Photoluminescence (PL) measurements perfo rmed on the best quality thermal cycle grown sample show a thermal str ain induced energy splitting of 3.8 meV between the free exciton emiss ions associated with heavy and light holes. Two other peaks in the PL spectra correspond to acceptor-bound (A(0),X)(mj=+/-3/2) and (A(0),X)( mj=+/-1/2) excitonic transitions, as confirmed by photoluminescence ex citation 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. (C) 1996 American Institute of Physics.