We present a new model of the piezo-tunnel effect in a heavily doped silicon p-n junction. Our approach is based on the coupling of a strain-dependent description of the energy exterma in the valence and conduction bands with the theory of indicrect tunneling developed by Kane. For any direction of stress and current flow, our model allows the calcuation of the current density as a function of the stress level, the bias voltage, the temperature and the doping concentrations at both sides of the junction. ALl silicon constants used in the numerical simulations are taken from literature, so that no fitting parameters have been used. The simulated tunneling current I, gauge factor K and temperature coefficients of carrent alpha and of gauge factor Beta are in fair agreeement with the experimental data measured on our integrated piezo-tunneling strain sensors.
Journal: TechConnect Briefs
Volume: Technical Proceedings of the 1999 International Conference on Modeling and Simulation of Microsystems
Published: April 19, 1999
Pages: 419 - 422
Industry sector: Sensors, MEMS, Electronics
Topics: Modeling & Simulation of Microsystems