Gallium arsenide piezotransistor for dynamic pressure measurements at high temperature

A piezotransistor concept for measuring transient pressures in combustion engines at high temperatures using the transversal piezoelectric effect in (100) GaAs is presented. The sensor was used without cooling to measure the pressure in a combustion chamber for a motored and fired engine. The results which are presented here are in good agreement with the signal from a commercial quartz sensor, which needs an additional preamplifier. Such an active GaAs sensor is therefore a very attractive alternative to the commonly used quartz sensors for dynamic pressure measurements at high temperatures. Compared to quartz sensors the GaAs sensor has the advantage of a possible integration of electronics on the sensor chip.