Optimization of the thermal drift caused by Joule heating in piezoresistive pressure sensor

The thermal drift provoked by the Joule heating in piezoresistive pressure sensors is a major source of imprecision for their applications requiring high accuracies measurements. This thermal drift affects greatly the performance of the such sensors. This work derives an accurate numerical model for optimization and predicting the temperature in piezoresistive pressure sensors due to the electric heater in its piezoresistors. In this case, by using the solution of 2-D heat transfer equation considering Joule heating in Cartesian coordinates for the transient regime, we determine how the temperature affects the sensor during the applying a supply voltage. In addition, the present study puts emphasis on the geometric effect of parameters on these characteristics to optimize the sensors performance. Finally, this study allows us to predict the sensor behaviour against temperature rise due to the Joule heating and to minimize this effect by optimizing the geometrical parameters and by reducing the applied voltage.