Patent ID: 7332995

Claim:
A capacitive humidity sensor comprising: a humidity sensing element, a capacitance of which is changeable in accordance with humidity so that the humidity sensing element detects the humidity; a substrate, on which the humidity sensing element is disposed; and an insulation film disposed on the substrate, wherein the humidity sensing element includes a pair of comb-shape electrodes and a humidity sensitive film, the comb-shape electrodes are interleaved so that the comb-shape electrodes face together, the comb-shape electrodes are disposed on the substrate, the humidity sensitive film covers the comb-shape electrodes through the insulation film, the humidity sensitive film has dielectric constant, which is changeable in accordance with the humidity, the comb-shape electrodes are surrounded by a dam, which is provided by a part of the insulation film, the insulation film disposed on the comb-shape electrodes has a first height from the substrate, the part of the insulation film disposed on the dam has a second height from the substrate, the second height being higher than the first height, the humidity sensitive film has a height equal to or lower than the second height, the humidity sensitive film is disposed inside of the dam, and the dam further includes a first ring pattern so that the first ring pattern surrounds the comb-shape electrodes and the humidity sensitive film, the first ring pattern which is made of a same material as the comb-shape electrodes.