| 摘要 |
PURPOSE:To obtain a capacitive microsensor without sacrifice of sensitivity or accuracy. CONSTITUTION:The capacitive sensor comprises a lower fixed electrode layer 2 of P<+> type impurity ion implantation layer formed shallowly on the major surface of an N type silicon substrate 1, a silicon oxide 3 deposited on the major surface of the substrate through thermal oxidation, a movable polysilicon electrode plate part 4 comprising a cantilever movable electrode part 4a having rear surface facing the silicon oxide 3 through a lower electrode plate gap G1, and an upper fixed electrode part 5 comprising an electrode plate part 5a having the rear surface facing the surface of the movable electrode part 4 through an upper electrode plate gap G2. Since the structure can be realized through a semiconductor fabrication process using a silicon substrate 1, the electrode plate gaps G1, G2 can be set at about 1mum and the planar area can be decreased. Since a process for assembling an independent component is not required, fluctuation in the electrode plate gap G1, G2 can be suppressed and the detection accuracy is enhanced. |
