Advanced Room-Temperature NIR Plasmonic Photodetection and Reconstructive Spectroscopy

Abstract

While Au is commonly utilized in semiconductor fabrication, its interaction with Si yields unstable contacts, posing potential reliability concerns. In this work, Cr interlayers were integrated to improve interface properties, enhance charge carrier transport within a plasmonic photodetector, and ensure long-term stability, demonstrated by consistent responses under zero bias and room-temperature conditions over the span of a year. The induced Fermi level shifts and Schottky barrier lowering to 0.59 eV, improving responsivity and extending the operation range beyond 1850 nm with increased sensitivity, allowing for precise reconstructive spectroscopy (RS). This is promising for reliable compound identification based on specific bond absorbance properties while scaling down IR spectroscopy to chip level, promoting applications like environmental monitoring and gas detection.