Differential capacitive pressure sensor based on ion pump effect and preparation method thereof

Abstract

The present invention discloses a differential capacitive pressure sensor based on ion pump effect and a preparation method thereof. The pressure sensor comprises a packaging frame, a differential pressure sensitive unit is arranged in the cavity of the packaging frame, and a pressure sensing unit is arranged on the top of the packaging frame; the differential pressure sensitive unit comprises an upper electrode, an upper dielectric layer, a middle electrode, a lower dielectric layer and a lower electrode stacked in sequence from top to bottom, each dielectric layer is composed of an ion transport layer close to the middle electrode and an ion adsorption layer far from the middle electrode, and a surface protrusion microstructure is arranged on the side of the ion transport layer facing the middle electrode, and the surface protrusion microstructure comprises a plurality of concentric annular protrusions; the pressure sensing unit comprises a pressing plate and at least two contacts, each contact is respectively inserted into each jack of the packaging frame and contacts with the surface of the middle electrode. The differential capacitive pressure sensor of the present invention has the characteristics of wide linearity, high sensitivity and weak temperature sensitivity.

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