CO gas detection utilizing Pd-SnO/sub x/ MIS heterostructure

The triangular voltage sweep method was used to study the device characteristics of Pd-SnO/sub x/ MIS heterostructure for detection of CO gas. An increase in area under the current peak in the J/sub p/-V plot and a shift of current peak toward more positive gate bias voltages were found with increasing CO gas concentration in an O/sub 2/ or Ar environment. Results indicate that CO gas reacts with preadsorbed oxygen ions, which interact with positive ions in the SnO/sub 2/ oxide layer, thus increasing the number of positive ions in the oxide of the MIS capacitor. It is concluded that preadsorbed oxygen ions in the SnO/sub 2/ play a more important role than the lattice oxygen for CO gas detection in the Pd-SnO/sub x/ MIS heterostructure.<
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