Abstract
A theoretical model for piezoresistance in both n- and p-type polycrystalline silicon is described. This model considers the contribution to piezoresistance from the grain and the Schottky-type barrier regions around the grain boundaries. Comparison between theory and experiment shows reasonable agreement for both longitudinal and transverse strain measurements. The difference in magnitude between longitudinal and transverse gauge factors depends on texture and is found to be explained by the anisotropy of piezoresistance in silicon. Experimental results for the temperature coefficients of resistance and gauge factor in conjunction with the model for piezoresistance may be used to optimise sensor characteristics within the confines of available processes.