Metalorganic vapor-phase epitaxy (MOVPE) growth of InGaAsP multiple-quantum-well distributed feedback lasers on InP corrugated substrate

We describe metalorganic vapor-phase epitaxy (MOVPE) growth of InGaAsP mult iple-quantum-well (MQW) distributed feedback (DFB) lasers. The MQWs and opt ical guide layers were grown directly on a corrugated InP substrate, whose corrugation was preserved by a layer pregrown in a mixed arsine and triethy lgallium flow at 350 degrees C. Before the pregrowth. only hydrogen flowed over the corrugated InP substrate. The corrugated InP substrate with the pr egrowth layer was heated to 650 degrees C in an arsine ambient, then an InG aAsP waveguide layer and MQW layers were grown. The pregrowth layer was con firmed to be InGaAsP, enabling us to grow a thin InGaAsP waveguide layer to realize small optical confinement inside the MQW active layers. A fabricat ed laser diode operating at 1.62 mu m showed a threshold current of 10.2 mA and an external quantum efficiency of 0.28 mW/mA at an ambient temperature of 25 degrees C. A side longitudinal mode suppression ratio of 40 dB at an optical output power of 10 mW was obtained, in the range from - 20 to 85 d egrees C. (C) 1999 Elsevier Science B.V. All rights reserved.