A study of surface exchange at semiconducting Ga{sub 2}O{sub 3} thin film sensors for better sensitivity and higher selectivity

Conference · Mon Dec 30 23:00:00 EST 1996

OSTI ID:441283

Seth, M; Fleischer, M; Meixner, H ^[1]

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1. Siemens AG Corporate Research and Development, Munich (Germany)

After the deposition of the surface layer, an annealing at least at 100{degrees}C above the desired operation temperature of the sensor for about 12h has been applied to ensure stability of the characteristics. The specimens have been characterised with respect to the surface morphology (SEM, AFM), atomic depth profile (SIMS, RBS) and crystalline phases (XRD) to identify the status of the applied material on the tempered sensor elements. The tested gases have been CH{sub 4}, CO, H{sub 2}, Iso-Butene, Acetone, Ethanol, NO, NH{sub 3} and a change of the oxygen concentration in wet air with concentrations typical for air monitoring. The temperatures tested range between 600-950{degrees}C. Long-term tests have been performed for some interesting modification. Especially with the oxides of the transition metaloxids, fundamental changes in the gas sensitivities of the sensors have been found due to their catalytic activity. Another important aspect was the change of the base resistance which showed whether the electrical conductivity occurs via the Ga{sub 2}O{sub 3} layer (as intender) or via the additional metal oxide layer.

• OSTI ID: 441283
• Report Number(s): CONF-960782--
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
33 ADVANCED PROPULSION SYSTEMS
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
54 ENVIRONMENTAL SCIENCES
ACETONE
AMMONIA
ANNEALING
BUTENES
CARBON MONOXIDE
DESIGN
ELECTRIC CONDUCTIVITY
ETHANOL
GALLIUM OXIDES
HYDROGEN
ION SCATTERING ANALYSIS
MEASURING INSTRUMENTS
METHANE
MONITORING
NITRIC OXIDE
OXYGEN
PERFORMANCE
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
THIN FILMS
X-RAY DIFFRACTION