Strain-insensitive soft pressure sensor and method of measuring pressure

Abstract

A soft pressure sensor comprises a stretchable top electrode, a stretchable bottom electrode, and an array of peaked structures between the stretchable top and bottom electrodes. The peaked structures comprise protruding regions of a continuous film conformally overlying an array of stiffening electrodes on the stretchable bottom electrode, where a tip of each protruding region is in contact with the stretchable top electrode and a base of each stiffening electrode is in contact with the stretchable bottom electrode. The soft pressure sensor includes one or more spacers extending between and bonded to the stretchable top electrode and the continuous film on the stretchable bottom electrode, where each of the one or more spacers is positioned outside the array of peaked structures. A capacitance measured by the soft pressure sensor is substantially invariant under in-plane stretching and/or bending.