Highly carbon-doped p-type Ga_0.5In_0.5As and Ga _0.5In_0.5P by carbon tetrachloride in gas-source molecular beam epitaxy

Highly carbon-doped, highly p-type Ga0.5In0.5As and Ga0.5In0.5P epilayers were grown by gas-source molecular beam epitaxy (GSMBE) using carbon tetrachloride (CCl4). Growth temperatures slightly below conventional values were used to increase the carbon incorporation, and a short-duration post-growth anneal near the growth temperature was necessary in order to obtain the highest hole concentrations, which were p=3×1019 cm-3 for Ga0.5In 0.5As and p=5×1018 cm-3 for Ga 0.5In0.5P. This is the first report of significant p-type carbon doping for Ga0.5In0.5P and the highest concentration from carbon doping yet reported for both ternary compounds. Reversible acceptor passivation from hydrogen species in the growth environment is a plausible explanation for the annealing behavior.