Metalorganic vapor phase epitaxy growth and characterization of quaternary (Ga,In)(As,Bi) on GaAs substrates

The incorporation of dilute amounts of Bi into the host lattice of a III/V semiconductor has a strong influence on its electronic properties. The bandgap is strongly redshifted which makes these materials interesting for application in the near- to mid-infrared regime. Furthermore, the spin-orbit splitting is increased resulting in suppression of hot-hole producing Auger recombination, which makes the fabrication of highly efficient optical devices feasible. However, for ternary Ga(As,Bi) grown using metalorganic vapor phase epitaxy (MOVPE), it has proven difficult to achieve the desired composition of the ternary material. Therefore, the additional incorporation of indium (In) into Ga(As,Bi), which should induce a further redshift of the bandgap, is investigated and summarized in this paper. For deposition of quaternary (Ga,In)(As,Bi), two different low temperature growth techniques using MOVPE are conducted. The strain and photoluminescence peak positions of the samples are correlated to estimate the composition of the (Ga,In)(As,Bi) layers. It was found that the trimethylindium and tertiarybutylarsine supplies need to be carefully adjusted to grow high quality bulk materials and that the incorporation of indium is inversely related to the amount of incorporated Bi.