Incorporation of thallium in InTlAs and GaTlAs grown by molecular beam epitaxy

Thallium incorporation in GaTlAs and InTlAs was systematically studied in solid source MBE by RHEED, Auger Electron Spectroscopy and X-ray diffraction as function of thallium concentration, substrate temperature and III/V flux ratio. Low temperature growth exhibits a (2/spl times/2) thallium-induced structure and also shows surface thallium accumulation. No evidence of binary TlAs formation was found. Auger electron spectroscopy measurements show limited thallium solubility in GaTlAs and InTlAs. X-ray diffraction measurements show the successful growth of epitaxial layers of TlGaAs with a molar fraction of Tl-0.5 and a second metal phase on the surface.