A new planar-type micro gas sensor in which a gas-sensing layer was surroun
ded by a platinum heater horizontally on the same plane of a diaphragm was
proposed to fit well to forming the gas-sensing layer by wet processes like
spin-coating. The planar-type sensor simply fabricated by using only three
masks for the photolithography processes shows very uniform temperature di
stribution over sensing layer and the device attached with a spin-coated th
in layer of metal oxide of SnO2, In2O3 or WO3 showed a reasonable sensing p
erformance to gases at 300 degrees C. (C) 2000 Elsevier Science S.A. All ri
ghts reserved.