上海科技大学知识管理系统

In this paper, we report an InP-based extended-short wave infrared (e-SWIR) phototransistor with InGaAs/GaAsSb type-II superlattices (T2SLs) as the absorber. Monolithic growth of the phototransistor on InP substrate enjoys several benefits such as the lattice matching property and convenient bandgap engineering of the InP/InGaAs/GaAsSb material system. At room temperature, the device exhibits a dark current density of 4.57 A/cm(2) under -0.8 V bias, and the responsivity at 2 mu m saturates at around 86 A/W. The corresponding thermal and shot noise limited specific detectivity is 6.59 x 10(10) cm center dot Hz(1/2)/W. The frequency response of the device is also measured by illuminating the device with a 2 mu m modulated laser. The device shows a 10% to 90% rise time of 44.2 ns. These characterization results suggest the high gain phototransistor with InGaAs/GaAsSb T2SLs on InP substrate is a promising candidate for e-SWIR applications.