Characteristics of a hermetic 6H-SiC pressure sensor at 600 C

Abstract

We report the fabrication and characterization of a single crystal hermetically sealed 6H-SiC pressure sensor tested up to 600°C. The pressure sensor was packaged by a novel microelectromechanical systems direct chip attach (MEMS-DCA) technique that eliminated the use of wire bonding, thereby removing the reliability issues associated with wire bonds at high temperature. The room temperature full-scale output (FSO) at 200 psi was 32.5 mV for a bridge input voltage of 5V, which gives a sensitivity of 32.5 |nV/V/psi. Although the full-scale output at 600°C dropped by 64 %, it maintained excellent linearity, with less than 2 mV null shift upon return to room temperature.