Characterization of AlGaAs/GaAs vertical-cavity surface-emitting laser diode grown on Si substrate by MOCVD

An AlGaAs/GaAs multi-quantum well vertical-cavity surface-emitting laser diode (VCSELD) has been grown on a Si substrate using metalorganic chemical vapor deposition. The VCSELD structure grown on a Si substrate consists of ten quantum well active layers and a 23-pairs of AIAs/Al,,Gac, As distributed Bragg reflector (DBR). The VCSELD on a Si substrate exhibited a threshold current of 82 mA and a threshold current density of 4.2 kA/cm* under continuous-wave (cw) condition at 1.50 K. Cross-sectional scanning electron microscopy observation showed quasi-periodic zigzag roughness and nonuniformity in the DBR structure. Auger-electron spectroscopy also showed compositional transitions at the heterointerfaces of DBR. A low reflectivity of the DBR on Si substrate is caused by the degraded heterointerfaces, which prevent 300 K cw operation for the VCSELD grown on Si.