The Application of Silicon-Based Schottky Infrared Photodetectors in Gas Detection

Non-dispersive infrared (NDIR) technology is a gas sensing method that utilizes mid-infrared spectroscopy for gas analysis and environmental monitoring, relying on characteristic absorption wavelengths caused by molecular vibrations. Due to bandgap limitations, developing silicon-based infrared detectors capable of detecting acetone at ppm levels with high sensitivity remains a significant challenge. In this study, we employed an inverted pyramid structure (IPS) to induce localized surface plasmon resonance (LSPR) in silicon-based Schottky devices, enabling the measurement of mid-infrared light. We then used the silicon-based Schottky infrared detector to detect acetone molecules (with a light source wavelength of 2.05 mu m), achieving measurement sensitivity below 50 ppm. The results confirm the high sensitivity of the device to infrared light signals and highlight its potential for future applications.