Chemical beam epitaxy of GaAs films using single-source precursors

Abstract

Two types of single-source precursors were studied that contained different Ga : As stoichiometry, [Me 2Ga(μ-AS- t-Bu 2)] 2 with a 1 : 1 stoichoimetry and Ga(As>- t-Bu 2) 3 with a 1 : 3 stoichiometry. Epitaxial films were grown from Ga(As- t-Bu 2) 3 on (100) GaAs in a chemical beam epitaxy system at 750 K and 6 × 10 −5 Torr. Temperature programmed desorption (TPD) studies for [Me 2Ga(μ- As- t-Bu 2)] 2 and Ga(As- t-Bu 2) 3 have been undertaken in a surface analysis chamber to develop an understanding of how precursor structure and reaction chemistry influence film properties. tert-Butyl ligands appear to react by β-hydride elimination process to isobutene and AsH. The methyl ligands appear to desorb rather than react with surface hydride to methane.