Modelling and Simulation of Mechanical, Thermal and Electrical Behaviour of Si Cantilever with Implanted Strain Gauge
M.Husak, J.Jakovenko, P. Kulha, Z. Výborný
Czech Technical University in Prague, Faculty of Electrical Engineering, Department of Microelectronics, CZ
Keywords: Microsystems, strain gauge, cantilever, simulation, modelling
The paper describes methodology of design of cantilever with implanted layers in Si monocrystal. In the paper there is characterized physical model of implanted strain gauges; various girder topologies are designed and basic technological steps during realization of cantilever are described. Simulation using ConvertorWare program is used for verification of mechanical properties and temperature distribution in cantilever structures. Suitable electric bridge connection of structure for evaluation of electric parameters of strain gauges at mechanic deformation and different temperatures has been designed. At realized structures of cantilever with strain gauges, there have been measured basic parameters, as dependence of electric parameters of strain gauges on mechanic deformation, temperature dependence at different mechanical load, temperature stability of output parameters, temperature dependence of pn junctions in the structure. From measured data there have been calculated piezoresistive coefficients, coefficients of deformation sensitivity, linearity, hysteresis, temperature coefficients of resistance, etc.
Measured characteristics shows very good linearity, small hysteresis and very good sensitivity. Based on the measured data, there has been designed connection of a simple electric equivalent model of the structure. The model describes resistance change in dependence on temperature and deformation and influence of reverse voltage value on pn junction.
NSTI Nanotech 2003 Conference Technical Program Abstract