National Research Council of Canada. Information and Communication Technologies
Doping; X-ray diffraction; Metalorganic chemical vapour deposition; Semiconducting quaternary alloys
We report on the effects of Zn-doping using diethylzinc (DEZn) on the growth of In₁₋xGaxAsyP₁₋y quaternary layers (x=0.18–0.41 and y=0.34–0.76) by metalorganic chemical vapour deposition. Independent of the quaternary layer compositions, a systematic reduction (increase) in Indium (Gallium) was observed. This was accompanied by a reduction in the overall growth rate, and increased tensile strain, with increasing DEZn flow. In contrast, the dependence of arsenic/phosphorus incorporation on DEZn flow was found to depend on the surface stoichiometry. We show quantitatively that the observed tensile strain can be explained by compositional variations caused by the Zn-doping process. These results suggest that DEZn affects both homogeneous and heterogeneous processes during the growth of InGaAsP layers.