Hydrocarbon Gas Sensors Based on Wide Band-Gap Semiconductors

19 Hydrocarbon Gas Sensors Based on Wide Band-Gap Semiconductors--SVT Associates, Inc., 7620 Executive Drive, Eden Prairie, MN 55344-3677; (612) 934-2100 Dr. Jody J. Klaassen, Principal Investigator Dr. Peter Chow, Business Official DOE Grant No. DE-FG02-97ER82491 Amount: $74,195 In order to reduce environmental pollution from automobiles, cleaner burning engines are necessary. The successful operation of clean burning engines requires simple, accurate sensors to monitor the combustion process. This project is to develop a solid sate chemical sensor based on new, wide band gap semiconductors which are sensitive to hydrocarbons found in gasoline and capable of operating at the high temperatures found in automobile exhaust systems. Such sensors would be able to provide feedback data for each cylinder stroke with respect to the efficiency of the cylinder¿s combustion. This data could then be used to regulate the air-to-fuel mixture to an optimum value resulting in minimum emissions during all stages of the engines operations. In Phase I simple capacitator sensors will be fabricated using aluminum gallium nitride (AlGaN) and silicon carbide (SiC) as the semiconductor material, aluminum nitride (AIN) as the insulator, and palladium and platinum as the catalytic metal. The devices will be tested for their sensitivity to hydrocarbons, ability to operate at elevated temperatures, speed of response, and long term reproducibility. The simplicity of fabricating capacitators will allow the numerous material parameters of the semiconductor, insulator, and catalytic metal to be investigated. More complex devices such as catalytic metal-insulator-semiconductor field effect transistors (CMISFETs) will be investigated in the Phase II portion of this project after more basic design parameters have been determined. Commercial Applications and Other Benefits as described by the awardee: Solid state chemical gas sensors based on these wide bandgap materials will have wide applicability for combustion diagnostics in the automotive, aeronautics, and aerospace industries as well as numerous applications for gas leak detection and air quality assurance.