Plasmonic enhanced CMOS non-dispersive infrared gas sensor for acetone and ammonia detection

Abstract

This work presents novel silicon-based plasmonic infrared emitters that can be used in non-dispersive infrared (NDIR) gas sensors for acetone and ammonia detection. Acetone is of interest for its increasing importance in air quality monitoring and diagnosing diabetes through breath analysis. Detection of ammonia is important due to its broad and diverse range of roles in various environmental processes and industrial technologies. The devices are designed to emit narrowband infrared radiation at the desired wavelengths of 8.26 μm and 10.6 μm for acetone and ammonia detection, respectively, and are relatively inactive at others wavelengths. They have the advantages of high selectivity, low power, low cost and are CMOS compatible. The silicon emitters were simulated using COMSOL, fabricated in a commercial foundry, and then tested on a gas bench rig in both dry and humid conditions. Our simulated and experimental results correspond well with each other and both sensors can detect acetone and ammonia in the concentration range from 50 ppm to 200 ppm and from 10 ppm to 20 ppm, respectively. The designed plasmonic NDIR is also integrated into a portable gas sensing unit.