High-sensitivity epitaxial Ge/PbSe/CdSe/Bi2Se3 p+pBn+ barrier heterojunction for uncooled middle infrared detection

Abstract

The inherent physical properties of common materials and fabrication techniques pose significant challenges for realizing low dark current and high sensitivity uncooled mid-wave infrared (MWIR) detectors. In this article, we propose and demonstrate a novel p+pBn+ barrier structure based on epitaxial Ge/PbSe/CdSe/Bi2Se3 single crystal heterojunction to suppress dark current at room temperature. The experimental results indicate that the lower dark current of the p+pBn+ barrier photodetector with 8.49 mA/cm2 is achieved. Moreover, this barrier device exhibits superior performance with a detectivity of 1.43×1010 cm·Hz1/2·W-1 and a responsivity of 1.41 A/W at room temperature. This work highlights the potential of PbSe-based p+pBn+ barrier structures for room temperature IR detection, providing both an industrialized technical solution and theoretical support for next-generation high performance uncooled MWIR detectors.