부산대학교 도서관

An eight terminal silicon piezotransducer (8TSP) was designed to be used as stress sensor, however, sensors based in the piezoresistivity effect have a large thermal drift of their characteristics due the dependence of the piezocoefficients with temperature. In this work, the temperature effect over the piezotransducer is observed and characterized, important information for an accurate measurement of the strain and to propose design strategies to compensate the piezotransducer output. The 8TSP is tested under controlled uniaxial stress at temperatures within the range [268K 353K], the output voltage is recorded and it is observed that sensitivity decrease with the temperature. Kanda's model is used to describe the relationship between piezoresistivity, temperature and doping concentration, introducing a correction factor P (N, T) for the piezocoefficients which decrease with temperature. The experimental sensitivity for each temperature is normalized and compared with the analytical value for the correction factor P(N, T) for low doping concentration, and seems to fit the proposed model.