Surfactant effects on doping of GaAs grown by organometallic vapor phase epitaxy

Recently, the addition of the isoelectronic surfactant Sb during organometallic vapor phase epitaxy (OMVPE) of GaInP was shown to eliminate ordering, resulting in a significant change in the band gap energy. These results suggest that surfactants added during growth could have profound affects on other important properties of semiconductors, such as doping. This letter presents the results of a recent study on the effects of the isoelectronic surfactant Sb on doping in GaAs. The addition of a small amount of triethylantimony during OMVPE of GaAs is found, using secondary ion mass spectroscopy analysis, to increase the Zn doping concentration from <6×1018 atoms/cm3 to 9×1018 atoms/cm3, a factor of 1.6. The amount of antimony introduced into the solid is only 2–3×1017 atoms/cm3. The addition of Sb also increases the impurity concentration of In in GaAs, but does not affect the concentration of Te or P.