New metal-organic precursors for growth of GaAs and AlxGa1−xAs by chemical beam epitaxy

✍ Scribed by A.C. Jones; P.A. Lane; T. Martin; C.R. Whitehouse

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 699 KB
• Volume: 17
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/0921-5107(93)90072-u

✦ Synopsis

The growth of GaAs and AI~Ga~ _wAs by chemical beam epitaxy (CBE) has traditionally utilized triethylgallium (Et3Ga) and either triethylaluminium (Et3A1) or triisobutylaluminium (i-Bu3AI). However, these precursors frequently give rise to layers which are significantly contaminated with carbon and oxygen impurities. Although the use of the hydride-based aluminium precursor trimethylamine alane (AIHa(NMe3)) has shown great promise in lowering oxygen contamination, the continued presence of carbon in GaAs and Al~Ga~_xAs layers grown using Et3Ga indicates that an alternative gallium precursor is required. We have therefore investigated triisopropylgallium (/-Pr3Ga), triisobutylgallium (/-Bu3Ga) and tri-tert-butylgallium (/-Bu 3 Ga) as precursors for GaAs and AI~Ga~ _ xAs grown by CBE. However, the use of t-Bu 3 Ga led to unacceptably low GaAs growth rates. In contrast, both i-Bu 3 Ga and/-Pr 3 Ga demonstrated improved performance over Et3Ga, allowing significant reductions in carbon contamination in CBE-grown GaAs and AlxGal _ xAs.