Environmental Influences on SMO Sensors' Performance

Micromachined semiconductor metal oxide (SMO) gas sensors have good prospect of being solution as future gas sensor technology in terms of sensitivity, robustness, simple signal processing, low production cost and small size. However, there are some challenges for the commercialization of SMO sensor to meet both performance-related and reliability-related requirements, especially false alarm problems caused by environmental induced drifts and shifts. Several environmental influence factors that affect SMO sensor's performance, in terms of temperature variation, relative humidity and possibly others like light and oxygen partial pressure, are discussed in this paper. Principles behinds these influences are presented and schemes of eliminating these influences are reviewed and proposed. Copyright © 2003 IFSA.