Growth of silicon- and carbon-doped GaAs by chemical beam epitaxy using H2-diluted DTBSi and CBr4 precursors

A wide range of n- and p-type doping levels in GaAs layers grown by chemical beam epitaxy is achieved by using H-2-diluted DTBSi and CBr4 as gas precursors for Si and C, respectively. We show that the doping level can be varied by modifying either the concentration or the flux of the diluted precursor. Specifically, we demonstrate carrier concentrations of 7.8 x 10(17)-1.4 x 10(19) cm(-3) for Si, and 1 x 10(17)-3.8 x 10(20) cm(-3) for C, as determined by Hall effect measurements. The dependence of Si incorporation on the diluted-precursor flux is found to be linear. In contrast, we observe a superlinear behavior for C doping. The dependence of the electron and hole mobility values on the carrier concentration as well as the analysis of the layers by low-temperature (12 K) photoluminescence spectroscopy indicate that the use of H-2 for diluting DTBSi or CBr4 has no effect on the electrical and optical properties of GaAs.

Automated summary

A wide range of n- and p-type doping levels in GaAs layers grown by chemical beam epitaxy can be achieved by adjusting the concentration or flux of diluted precursors. The incorporation of Si shows a linear dependence on the diluted-precursor flux, while C doping exhibits a superlinear behavior. Analysis by low-temperature photoluminescence spectroscopy suggests that diluting DTBSi or CBr4 with H-2 does not affect the electrical and optical properties of GaAs.