Patent ID: 7032448

Claim:
A capacitive humidity sensor, comprising: a semiconductor substrate; a detection portion including: a pair of detection electrodes disposed to oppose each other on the semiconductor substrate; and a moisture sensitive film disposed on the pair of detection electrodes, so that the moisture sensitive film changes a capacitance thereof according to humidity; a reference portion including a pair of reference electrodes disposed to oppose each other on the semiconductor substrate; a converting means for converting a difference between a capacitance of the pair of reference electrodes and a capacitance of the pair of detection electrodes to an electric signal; and a capacitance adjusting gel film disposed on the pair of reference electrodes in order to reduce a difference between the capacitance of the pair of reference electrodes and the capacitance of the pair of detection electrodes in a reference humidity condition, wherein the detection electrodes and the reference electrodes are substantially equal in pattern and size; and wherein the moisture sensitive film and the capacitance adjusting gel film have substantially equal permittivity in the reference humidity condition.