ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Metalorganic molecular beam epitaxy (MOMBE) growth characteristics of GaAs using triethylgallium (TEGa) and trisdimethylaminoarsenic (TDMAAs) are studied in detail by using reflection high energy electron diffraction intensity oscillations. It is found that the GaAs growth rate variation with substrate temperature (Tsub) is similar to that in the MOMBE growth of GaAs with TEGa and elemental As (As4) except in the high Tsub region, despite the use of uncracked TDMAAs instead of As4. GaAs growth starts at about 350 °C and shows a maximum growth rate at about 500 °C. However, the absolute growth rate is about 15% lower than that using As4 with the same TEGa flow rate in the mass-transport limited growth region. Above 600 °C the growth rate shows a rapid decrease with increasing Tsub. Further, it is found that etching of GaAs occurs when only TDMAAs is supplied to the GaAs surface at Tsub above 500 °C. Unintentionally doped GaAs films show n-type conduction in the whole Tsub range investigated with the highest 77 K electron mobility of 22 000 cm2/V s and a low carrier concentration of 2×1015 cm−3 for the 650 °C grown samples. 4.2 K photoluminescence spectra show an exciton-bound-to-impurity emission peak at the wavelength of 819.3 nm with a full width at half-maximum of less than 3.5 meV indicating good optical qualities. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.358829
