Fabrication and initial characterisation results of a micromachined biomimetic strain sensor inspired from the Campaniform sensillum of insects

In this report, we present our initial fabrication and characterisation results of a new micromachined biomimetic strain sensor. The new strain sensor is structurally inspired from the natural strain sensor found in insects, commonly called Campaniform sensillum. The high-sensitivity strain sensing capability of Campaniform sensillum is among other things due to its hole-structure, as well as its membrane-in-recess structural features. From previous works in continuum macromechanics, it is widely known that hole-structure amplifies stress and mostly becomes a crack starting point. We fabricated for the first time micromachined Si-based strain-sensing structures inspired from these structural features of Campaniform sensillum. In our initial optical characterisation results of these biomimetic Si-based microstructures, it is confirmed that the hole structural feature amplifies and concentrates strain. Thus, further application for a strain-sensing device is feasible.