STTR Phase I: Self-Calibrating, High Sensitivity, Harsh Environment Gas Sensors

The broader impact/commercial potential of this project will be to address the gap between the low-end gas sensor market, dominated by semiconductor and electrochemical gas sensors, and the high-end gas sensor market, dominated by infrared gas sensors. Augmenting the capabilities of semiconductor gas sensors will close this gap, which will expand their use in existing applications and disruptively open up new applications, especially in cost-sensitive industrial applications. This will help satisfy the progressive demand for gas sensors driven by increasing government regulations for workplace safety and emission control. The technology can be universally applied for the detection of gases that constitute a majority of the global market?carbon dioxide, oxygen, hydrogen, methane, and carbon monoxide, among others?which will be further explored during Phase II. The technology can also be applied for the detection of biological agents, such as proteins, cancer cells, or DNA. This STTR project will advance existing electronic materials and device technology, whose results will be disseminated through archival journal articles and conference presentations. In addition, a Hispanic graduate student will be participating in the project and will have the opportunity to spend time at the small business concern and conduct research in a small business environment. This Small Business Technology Transfer Research (STTR) Phase I project will develop high sensitivity gas sensors based on enhancement-mode AlInN/GaN high electron mobility transistors (HEMTs) with functionalized gate electrodes to provide for self-calibration and operation in harsh environments. The use of lattice-matched AlInN eliminates the piezoelectric polarization typically found in III-nitride materials, especially at elevated temperatures, while the use of enhancement-mode (normally-off) operation enables self-calibration of the gas sensor by having a zero background signal. While sensitivity to a particular gas is determined by the choice of functional coating, the Phase I effort will focus on hydrogen gas sensors with the goal of achieving sub-ppm sensitivity. The first half of the effort is devoted to optimizing the material and device properties of the enhancement-mode AlInN/GaN HEMTs with respect to hydrogen sensitivity. The second half of the effort is devoted to the integration and packaging of the HEMTs into a hydrogen gas sensor and testing under adverse conditions. If successful, this research will enable new capabilities in low-cost semiconductor gas sensors, especially for harsh environment applications.