Metalorganic molecular beam epitaxy of 1.3 μm quaternary layers and heterostructure lasers

Metalorganic molecular beam epitaxy of InGaAsP quaternary layers with the composition corresponding to the band gap at 1.3 μm has been investigated for growth temperatures ranging from 485 °C to 530 °C. From the x-ray diffraction and room temperature photoluminescence measurements Ga incorporation was found to be extremely growth temperature dependent. Photoluminescence linewidths increased rapidly for a negative lattice mismatch exceeding the critical value, whereas for positive mismatch no such broadening was observed. For lattice matched layers linewidths were broader for the higher growth temperatures. Threshold current densities ranging from 0.7 to 2.0 kA/cm2 were measured for conventional and multi-quantum-well broad area lasers with the active layers based on the 1.3 μm quaternary.