Temperature compensation of amorphous silicon strain gauges

Abstract

The applied potential of amorphous silicon as a strain gauge material has been investigated. Measurements of the gauge factor, K, were carried out on a-Si/a-SiN_x thin-film structures deposited from a glow discharge plasma on polished stainless steel substrates. The conductance changes of phosphorus-doped a-Si under uniaxial strain lead to room temperature K values between −20 and −40, depending on the potential applied to the substrate. The control of K by the field effect makes it possible in principle to compensate for the temperature coefficients of the gauge factor.