High compositional uniformity and reproducibility of InGaAsP in multi-wafer metalorganic vapor phase epitaxy

We report the results of compositional uniformity over 2-inch InP wafers and the run-to-run and wafer-to-wafer reproducibility for an InGaAsP quaternary alloy that has a bandgap wavelength of λg=1.3 μm. We used the multi-wafer metalorganic vapor phase epitaxy system that has multiple gas injectors, a wafer rotation system, and a zone-controlled heating system. It is found that the poor reproducibility of the room temperature photoluminescence peak wavelength results from deviations in P/As content, which is sensitive to variations in wafer temperature. By eliminating the effect of variations in wafer temperature, we achieved an extremely high compositional uniformity of less than ±1.5 nm and a run-to-run and wafer-to-wafer reproducibility of σ=1.2 nm for InGaAsP quaternary alloy