ZnTe Buffer Layer Research Articles

Direct molecular-beam epitaxial growth of ZnTe(100) and CdZnTe(100)/ZnTe(100) on Si(100) substrates

Epitaxial structures of ZnTe(100) and CdZnTe(100)/ZnTe(100) have been deposited by molecular-beam epitaxy onto Si(100) substrates misoriented from 0° to 8° towards the [011] direction. The films were characterized with x-ray diffraction, photoluminescence spectroscopy, optical microscopy, and stylus profilometry. Single-crystal CdZnTe(100) films comparable in structural quality to those obtained with growth on GaAs/Si composite substrates have been demonstrated on both 4° and 8° misoriented Si with the use of ZnTe buffer layers. X-ray rocking curves with FWHM less than 300 arcsec for ZnTe (400) and less than 160 arcsec for CdZnTe(400) have been obtained for as-grown films. Specular surface morphologies, superior to those obtained on GaAs/Si composite substrates, are also observed.

Direct Heteroepitaxial Growth of ZnTe(100) and CdZnTe(100)/ZnTe(100) on Si(100) Substrates by MBE

ABSTRACTEpitaxial films of ZnTe(100) and CdZnTe(100)/ZnTe(100) have been deposited by molecular-beam epitaxy onto Si(100) substrates misoriented from 0-8 degrees towards the [011] direction. The films were characterized with x ray diffraction, photoluminescence spectroscopy, optical microscopy, and stylus profilometry. Through use of ZnTe buffer layers, single crystal CdZnTe(100) films have been demonstrated on both 4° and 8° misoriented Si with structural quality comparable to that obtained with GaAs/Si composite substrates. X ray rocking curves for ZnTe(400) with FWHM less than 300 arcseconds and for CdZnTe(400) with FWHM less than 160 arcseconds have been obtained for as-grown films. The observed surface morphologies are superior to those obtained on GaAs/Si composite substrates. HgCdTe(100) films with x ray FWHM as low as 55 arcseconds and average etch pit densities of 5 x 106 cm−2 have been deposited by liquid phase epitaxy on these MBE CdZnTe/ZnTe/Si substrates.

Molecular beam epitaxy of a low strain II-VI heterostructure: ZnTe/CdSe

We report the growth of a new closely lattice-matched II-VI heterostructure: ZnTe/CdSe (Δa/a∼0.3%). Epilayers of zinc blende CdSe grown on ZnTe buffer layers are shown to have much better quality than those grown earlier (with a 7% mismatch) on GaAs substrates. This permitted the first successful growth of high quality superlattices of ZnTe/CdSe. The superlattices were studied by x-ray diffraction, transmission electron microscopy, and optical techniques. Results of photoluminescence and optical transmission measurements show that ZnTe/CdSe superlattices have a very small valence-band offset.

MOCVD growth of CdTe-ZnTe superlattices

We report for the first time the MOCVD growth of CdTe-ZnTe superlattices. The superlattices were grown on (001) GaAs substrates using a CdTe or ZnTe buffer layer. A typical cross-hatch pattern which can be related to strain relief was found in all superlattices which were not matched to their buffer layer. X-ray diffraction patterns indicated that the superlattices were free standing irrespective of the buffer layer used. The periodicity of the superlattice was deduced from the satellite peak sequence.

Here's why solar heating lags : Jordan, R. C., Heat. Pip. Air Cond. 29(7): 111–14, July 1957

Single quantum wells (SQW) and superlattices of mercury-iron selenide (HgSe:Fe) have been grown by molecular beam epitaxy (MBE) and characterized by in-situ high-energy electron diffraction (RHEED) and magneto spectroscopy investigations. The influence of the structural parameters of the ZnTe buffer layer on the properties of the HgSe:Fe microstructures has been investigated by RHEED-mosaic structure analysis. The onset of strain relaxation at the critical thickness has been determined by intensity-profile analysis of different reflexes in the RHEED pattern. These results are compared with high resolution X-ray measurements (HRXRD) of the lattice relaxation of the HgSe layer. Different types of HgSe:FeHgSe quantum well structures and superlattices have been characterized by magneto transport investigations. The clear resolved plateau structure of the Hall voltage (Quantum Hall Effect) indicates the existence of a Q2D electron gas in the layers which is also corroborated by the cosine dependence of the peak shift of the Shubnikov de Haas (SdH)-oscillations in tilted magnetic fields.