Effects of charge collectors in ferroelectric E-field sensors

A nonlinear dynamical system based on ferroelectric capacitors coupled into a unidirectional ring circuit, which under particular conditions exhibits an oscillating regime of behavior, is considered with particular interest for developing novel electric field sensors. For such a device a weak, external, target electric field interacts with the system thus inducing perturbation of the polarization of the ferroelectric material; the target signal can be indirectly detected and quantified via its effect on the system response. The conceived devices exploit the synergetic use of bi-stable ferroelectric materials, micromachining technologies that allow us to address charge density amplification, and implement novel sensing strategies based on coupling non-linear elemental cells. The “charge collector” strategy, already discussed in [1], has been employed to detect the target field. An experimental characterization of the whole circuit, including three cells coupled in a ring configuration, has been carried out. The effect of the dimensions of the charge collectors has also been investigated.