Growth and Evaluation of High-Quality ZnTe/GaAs by Hot Wall Epitaxy

Abstract

In order to grow high-quality ZnTe epilayers on (100) GaAs substrates by improved hot wall epitaxy (HWE), the optimum growth condition including the reservoir temperature has been determined by the full-width at half-maximum (FWHM) of the four-crystal rocking curve and the low temperature photoluminescence (PL). Under the determined optimum growth condition, ZnTe epilayers with thickness of 0.7-24.8 mm were grown for studying the effect of the thickness on the crystalline quality. The PL and FWHM values indicated that the quality of ZnTe epilayers was significantly improved when increasing their thickness up to 6 mm. The narrowest FWHM value of 66 arcsec was obtained on an epilayer with 13 mm thickness. Meanwhile, the typical PL spectrum showed the strongly split free exciton emissions and very weak deep band emissions. These results show that the ZnTe epilayers are of high quality.

Characterization of extended defects of ZnTe/GaAs(100) hetero-interface by advanced transmission electron microscopy

“…It is considered that the quality of the epilayer in ZnTe (12 µm)/GaAs is much better than that of ZnTe (0.7 µm)/GaAs. Furthermore, it is noted that the value (66 arc s) of the FWHM in (b) is the best value so far reported to our knowledge, and the high quality of the ZnTe epilayer was confirmed by photoluminescence and reflection spectra in our co-workers' paper [9].…”

“…ZnTe films were grown on (100) GaAs substrates by hot wall epitaxy (HWE), which could be carried out under near thermal-equilibrium condition at all the steps by installing a hot wall between the source and the substrate. The detailed setup and epitaxial conditions of the HWE have been described elsewhere [9].…”