High-quality InGaAsP lattice matched to InP was grown by low-pressure metalorganic vapor phase epitaxy using ethyldimethylindium (EDMIn), tertiarybutylphosphine (TBP), and tertiarybutylarsine (TBA). The background carrier concentrations of undoped InP and InGaAs were as low as 1.5×1015 and 2.2×1015 cm−3, respectively. Good compositional control of In-GaAsP was also possible. The performance of the double heterostructure wafers employed as lasers as characterized by threshold current density, internal loss, and internal quantum efficiency. The threshold current density for a 300-μm cavity was as low as 2.0 kA/cm2. In addition, ridge-waveguide distributed feedback lasers were successfully fabricated. These results show that EDMIn, TBP, and TBA might be used to replace conventional sources for growing InGaAsP/InP lasers.