LINEAR AND NONLINEAR PIEZORESISTANCE COEFFICIENTS IN CUBIC SEMICONDUCTORS .1. THEORETICAL FORMULATIONS

This paper constitutes the first part of a work devoted to application s of piezoresistance effects in germanium and silicon semiconductors. In this part, emphasis is placed on a formal explanation of non-linear effects. We propose a brief phenomenological description based on the multi-valleys model of semiconductors before to adopt a macroscopic t ensorial model from which general analytical expressions for primed no n-linear piezoresistance coefficients are derived. Graphical represent ations of linear and non-linear piezoresistance coefficients allow us to characterize the influence of the two angles of cut and of directio ns of alignment. The second part will primarily deal with specific app lications for piezoresistive sensors.