MOVPE GROWTH OF STRAINED INASP/INGAASP QUANTUM-WELL STRUCTURES FOR LOW-THRESHOLD 1.3-MU-M LASERS

Device-quality strained InAsP/InGaAsP multiple-quantum-well (MQW) structures are successfully grown using low-pressure metalorganic vapor phase epitaxy method. The grown MQW structures are characterized using X-ray, photoluminescence, and photocurrent measurements that confirm that their structural and optical qualities are high enough for practical device applications, as well as that the InAsP/InGaAsP heterostructures have a large conduction-band offset. The grown wafers are processed into 40-mum-wide stripe-ridge waveguide lasers. Threshold current densities as low as 88 A/cm2 are achieved for a graded-index separate-confinement-heterostructure (GRIN-SCH) single-quantum-well laser diode. Buried heterostructure laser diodes fabricated from GRIN-SCH 4-well strained MQW wafers have threshold current as low as 1.05 mA at 26-degrees-C and 7.2 mA at 106-degrees-C.