A study on the fabrication and electrical characteristics of barometric sensors for USN

In this paper, we fabricated ceramic body and sapphire wafer in order to develop a barometric sensor with high sensitivity and high temperature stability for ubiquitous sensor network. The sapphire wafer was adopted with a membrane of capacitance ceramic pressure sensor. The capacitance value of the sensor for the finite element analysis(FEM) showed a linear pressure characteristics. Membrane was processed with a diameter of 32.4mm and a thickness of 1mm by using alumina powders. Ceramic body was processed with a diameter 32.4mm and a thickness 5mm. The capacitance pressure sensor was made with high heat treatment of the ceramic body and the sapphire wafer. Initially capacitance of the pressure sensor was 50 pF and a capacitance of 110 pF was measured from 5 bar pressure. Output voltage of 5 V was appeared at 5 bar pressure. Respectively-suitable for application as the electric power source of a ubiquitous sensor network (USN) sensor node.