HIGH-RELIABILITY GAAS ALGAAS MULTIQUANTUM-WELL LASERS GROWN AT A LOW-TEMPERATURE (375-DEGREES-C)/

We report on high-reliability GaAs/AlGaAs multiquantum well (MQW) lase rs grown at a low temperature (375-degrees-C) by molecular beam epitax y (MBE). Typically, a threshold current (I(th)) of 26 mA and a differe ntial quantum efficiency of 62% were obtained during a continuous wave (cw) operation at room temperature. During the life test, a stable op eration was observed beyond 5000 h under a 20-mW cw operation at 70-de grees-C. We also observed an improvement of laser characteristics in l ow-temperature-grown MQW lasers during a cw operation at room temperat ure. The threshold current of our MQW lasers was reduced from 26 to 18 mA, and this suggests that the point defects in the low-temperature-g rown MQW laser were decreased.