Gas Sensing Based on Inelastic Electron Tunneling Spectroscopy

Odor detection with high reliability and selectivity is increasingly in demand in several fields, including defense, homeland security, clinical diagnosis, and air monitoring. Poor selectivity and reliability of existing gas sensor technology has been a major impediment in the development of a versatile odor detector. This work describes a new gas sensor technology based on inelastic electron tunneling spectroscopy (IETS) that may be able to identify gas molecules based on chemical bonds. The IETS responses of metal-insulator-metal tunnel junctions were measured at 77 and 300 K and the results suggest the potential of gas detection with ppm sensitivity. Despite thermal broadening, IETS peaks can be analyzed for room temperature gas identification.