Theoretical design of uncooled mid-infrared PbSe P⁺pBn⁺ barrier detectors

Abstract

A novel uncooled Mid-wavelength infrared (MWIR) P+pBn+ barrier detector based on epitaxial PbSe absorber layer on Ge substrate is theoretically investigated by finite element analysis in order to achieve optimal detection performance. The simulated results show that the P+pBn+ barrier architecture can further effectively reduce the room-temperature dark current to 4.45 mA/cm2 under -0.1 V bias, which is lower 12 times than PbSe pBn+ unipolar barrier device in previous work. Moreover, the P+pBn+ barrier architecture exhibits excellent responsivity and detectivity of 1.83 A/W and 3.23×1010 cm Hz1/2 W-1 at 3.8 μm, respectively. These results suggest that this P+pBn+ barrier detector based on matural MBE epitaxy technologies could be potential in the emerging high-sensitivity and high-detectivity uncooled MWIR applications.