Design of strain gauge structure

Abstract

The paper describes the design of a strain gauge on a cantilever with implanted layers. In the paper, the physical model of implanted strain gauges is characterized and basic technological steps are described. Simulation using CoventorWare (MEMCAD) program is used to verify the mechanical properties and temperature distribution in cantilever structures. A suitable electric bridge connection of the structure for evaluation of electric parameters of strain gauges at mechanic deformation and different temperatures has been designed. On realized structures, basic parameters have been measured such as the dependence of electric parameters of strain gauges on mechanical deformation, temperature dependence at different mechanical load, temperature stability of output parameters, and temperature dependence of pn junctions in the structure. From the measured data, piezoresistive coefficients of deformation sensitivity, linearity, hysteresis, temperature coefficients of resistance, etc. have been calculated. The measured characteristics show very good linearity, small hysteresis and very good sensitivity.