Polarization-modulation diagnostics of thermal stresses in an integrated pressure transducer

Abstract

A semiconductor pressure transducer consisting of a sensing resistor implanted into a silicon membrane as an elastic mechanical element is studied by the modulation polarimetry technique. Internal mechanical stresses are detected. The coordinate distributions of uniaxial stresses are measured in two cases: stresses remaining from local crystal doping inhomogeneities and stresses caused by heating by flowing current. The coordinate distribution of the temperature caused by the heat flux released by the resistor current is determined by double integration of the stress function, taking into account corresponding boundary conditions.