Growth of high-quality GaAs by MBE

This paper reviews the requirements and current practices in the molecular beam epitaxial (MBE) growth of high-quality GaAs. Experimental data are presented which show an excellent control on the growth rate and its lateral uniformity (± 0.75 per cent), the presence of very low-level of background impurities (approx. low 1013 cm-3) and high electron mobilities (μpeak approx. 3 × 105 cm2 V-1s-1 at 42 K for n approx. 3 × 1013 cm-3). In addition, we show that MBE-GaAs is intrinsically free from electron and hole deep traps. Chemical impurities in the impure arsenic source are shown to be the main limiting factors in determining the transport and optical properties and formation of deep centers in MBE-GaAs. Such chemical impurities may, however, originate from other sources as well.