A high-sensitivity 3-D tactile sensor for minimally invasive surgery

This paper reports the development of a tactile sensor that is able to detect 3-D forces for minimally invasive surgery (MIS) applications. The sensor consists of a central silicon post and a polyimide bottom diaphragm integrated with symmetric polysilicon piezoresistors. A straightforward fabrication process using Deep Reactive Ion etching (DRIE) was employed. A simple but effective packaging scheme was developed, isolating the bonding pads and bonding wires from the sensing surface. The tactile sensor was experimentally characterized by monitoring the resistance change of the piezoresistors when the central post was pushed.