InP-Based Broadband Photodetectors With InGaAs/GaAsSb Type-II Superlattice

In this work, an In0.53Ga0.47As/GaAs0.5Sb0.5 type-II superlattice(T2SL) based broadband photodetector with an optical spectrum response ranging from 250 nm to 2400 nm is demonstrated. The photodetector shows a low dark current density of 3.48 x 10(-4) A/cm(2) under the bias of -1 V and a specific detectivity (D*) of 1.59 x 10(10) cm.Hz(1/2)/W at 2 mu m at 293 K. A recessed window on the surface of the top P layer was fabricated to enhance the responsivity of ultraviolet (UV) and visible band. The UV and visible band quantum efficiency (QE) can increase by 40% with the recessed window.

Automated summary

In this work, a broadband photodetector based on In0.53Ga0.47As/GaAs0.5Sb0.5 type-II superlattice (T2SL) is demonstrated, with an optical spectrum response ranging from 250 nm to 2400 nm. The photodetector exhibits low dark current density and high sensitivity, and the responsivity of the UV and visible band is enhanced by fabricating a recessed window.