Optical detection of nanotweezers´ actuation

Silicon tweezers consisting of free-standing nanometer-sized prongs are investigated. These nanotweezers are fabricated using electron beam lithography as well as dry and wet etching processes. Due to electrostatic forces, they are deflected under a bias voltage applied to the prongs. An optical method to demonstrate the functionality under quasi-static conditions is presented. We discuss the demodulated signals measured at the 1st to 3rd harmonics, analyzing the amplitudes and phases. Comparison with a simple optical model leads to a quite good understanding of our experimental results. This technique should be easy to transfer to other NEMS.