High-temperature ceramic pressure sensor

A pressure microsensor for working at high temperature has been developed. The device consists of a tantalum nitride thin film, patterned on a Wheatstone bridge configuration, sputter-deposited onto thermally oxidized silicon wafers with an aluminium interconnection layer and a silicon dioxide passivation. The microsensors present a low temperature coefficient of resistance and good long-term stability. The sensitivity is 0.15 mV (V bar)^?1 with low sensitivity drift and low combined non-linearity and hysteresis in the pressure range 0–10 bar.