POSFET touch sensor with CMOS integrated signal conditioning electronics

This paper presents the design, fabrication and evaluation of the new version of POSFET (Piezoelectric Oxide Semiconductor Field Effect Transistor) touch sensing device based tactile sensing chip. Implemented using CMOS (Complementary Metal Oxide Semiconductor) technology, the chip consists of POSFET device and the integrated bias and signal conditioning circuitry. In particular, a high compliance current sink and an output buffer have been integrated to respectively bias the POSFET device and to decouple the sensor from chip output. The performance of tactile sensing chip has been evaluated in the dynamic contact forces range of 0.01–3 N and the sensitivity of POSFET devices (without amplification) is 102.4 mV/N.