OPTICAL AND X-RAY-ANALYSIS OF ZNSXSE1-X ZNSE SUPERLATTICES GROWN ON GAAS BY METALORGANIC VAPOR-PHASE EPITAXY/

X-ray diffractometry, Raman backscattering and photoluminescence were applied to characterize ZnSxSe1-x/ZnSe superlattices, grown on GaAs(10 0) by metalorganic vapour phase epitaxy (MOVPE). As sulphur precursor materials diethylsulphide (DES) and H2S were compared. Furthermore, we investigated the influence of different kind of buffer layers, the ef fect of increasing the number of periods and the consequences of stabi lization during growth interruptions. Superlattices with a high crysta l quality and very regular periodicity were obtained for 120-period st ructures, grown with DES as precursor, without intentional buffer laye r. They show very narrow folded acoustical phonons in the Raman spectr um and their X-ray diffraction pattern contains not only sharp satelli te peaks, whose fine structure reveals monolayer fluctuations, but als o fringes which are due to interference from the entire stack.