Title :
Discriminating gas concentrations in extreme temperature environments
Author :
Furnival, B.J.D. ; Wright, N.G. ; Horsfall, A.B.
Author_Institution :
Sch. of Electr., Electron. & Comput. Eng., Newcastle Univ., Newcastle upon Tyne, UK
Abstract :
In this paper a Pt/HfO2/SiO2/SiC MIS capacitor is reported, which unlike previously documented Pt/SiO2/SiC and Pd/TiO2/SiO2/SiC devices shows no response to O2 ambients. As a result, if the capacitor is used within a sensor array it could significantly improve selectivity between H2 and O2. The use of SiC as the substrate material also enables this device and the potential array to operate in extreme conditions, where standard electronics fail. Examination of the devices sensing mechanisms reveal that in contrast to previous reports, a positively charged dipole layer is not formed during exposure to O2. Whilst the passivation of trapping states at the SiO2/SiC interface have little influence on the response to either H2 or O2.
Keywords :
MIS capacitors; gas sensors; hafnium compounds; platinum; silicon compounds; MIS capacitor; Pt-HfO2-SiO2-SiC; device sensing mechanisms; extreme temperature environments; gas concentrations; Capacitance-voltage characteristics; Capacitors; Hafnium compounds; Sensitivity; Silicon; Silicon carbide;
Conference_Titel :
Sensors, 2011 IEEE
Conference_Location :
Limerick
Print_ISBN :
978-1-4244-9290-9
DOI :
10.1109/ICSENS.2011.6127132
