HOW ACCURATE ARE MEASUREMENTS WITH PIEZOR ESISTIVE SENSORS

Piezoresistive sensors have found widespread applications (e.g. in car industry, chemical engineering, industrial measurement techniques, et c.). Besides the highly developed technology of piezoresistive sensors the attainable accuracy and resolution, respectively, cannot satisfy up to date. Beginning with the state-of-the-art the paper gives a deta iled description of the metrological model used. On the behalf of this model the transfer and error characteristics of piezoresistive sensor s can be given in terms of specified parameters. In the model the tran sfer and error functions of the measuring quantity as well as disturbi ng influences caused by ambient temperature and/or humidity changes ar e taken into consideration. Especially, the introduced error of reprod ucibility allows us to determine the accuracy in real practical applic ation. On the basis of these parameters we investigated differently pr oduced pressure sensors. We found that the accuracy of piezoresistive sensors can be improved significantly by using highly performed passiv ation systems.