The MOVPE growth and characterization of Hg1-xMnxTe
The authors report the influence of growth conditions and substrate type on the quality of Hg1-xMnxTe (MMT) epitaxial layers. MMT epitaxial layers were grown using di-isopropyl telluride (DIPTe) tricarbonyl methylcyclopentadienyl manganese (TCMn) and elemental Hg in a horizontal atmospheric-pressure MOVPE reactor. Mn concentration depends strongly on both growth temperature and position of the substrate on the susceptor. This is primarily due to the large difference in pyrolysis characteristics between the DIPTe and TCMn precursors. Epitaxial growth was possible up to x approximately 0.8 but high growth temperature led to polycrystalline deposition. Investigation of the morphology and crystallinity of the epitaxial layers on GaAs (100), (Cd, Zn)Te (100) 2 degrees off to nearest (110), (211)B and (111)B substrates revealed that (Cd, Zn)Te (100) 2 degrees off to nearest (110) substrate was the most suitable of all tested substrates. The room-temperature reflectance and transmission spectra over the wavelength range 0.3-30 mu m were taken. Thicknesses of the films have been estimated from the interference fringe peaks near 20 mu m. The optical transition Lambda 4.5v- Lambda 6c (the E1 peak) and its doublet (the E1+ Delta 1 peak), the absorption edge in transmission, and the behaviour of the interference extrema with Mn composition have been examined.