Dependence of carbon incorporation on crystallographic orientation during metalorganic vapor phase epitaxy of GaAs and AlGaAs

Abstract

We studied the dependence of carbon (C) incorporation on the crystallographic orientation during metalorganic vapor phase epitaxy (MOVPE) of GaAs and AlGaAs. We performed C doping to GaAs grown with trimethylgallium (TMGa) and AsH 3 and Al 0.35Ga 0.65As grown with trimethylaluminum (TMAl), TMGa or triethylgallium (TEGa), and AsH 3 on the surface lying between (100) and (111) A/B. C and hole concentrations nearly coincided over the entire orientation range, showing that C is preferentially incorporated at As sites, irrespective of orientation. We found that the dependence of C incorporation on the orientation is more complex than previously thought. The dependence of carrier concentration on the AsH 3 partial pressure reflected the degree of C incorporation very well. Using simultaneous doping with C acceptors and Si donors, we fabricated lateral p-n junctions on patterned substrates composed of the (100) principal surface and (411)A/B sidewalls.