Low-threshold pulsed operation of long-wavelengthlasers on Sifabricated by direct bonding

Low-threshold room-temperature pulsed operation of InGaAs/InGaAsP multiquantum-well (MQW) lasers (λ ≃ 1.55 µm) on Si substrates is demonstrated. These laser structures were first grown on InP substrates, then bonded at 700°C onto Si substrates with buffer layers. The mesa-stripe broad-area lasers have a threshold current density of 1.7 kA/cm2 (50 µm mesa width, 330 µm cavity length), which is comparable to the value for lasers on InP substrates.