Piezoelectric polymer oxide semiconductor field effect transistor (POSFET) devices for touch sensing

This work presents the POSFET based touch sensing devices and their experimental evaluation. POSFET touch sensing devices presented here are primarily developed for the robotic applications. The design of these devices is inspired from human sense of touch. These devices are implemented by spin coating thin (~2.5 μm) piezoelectric polymer (PVDF-TrFE) film, directly on to the gate area of MOS transistor. The polymer film is processed in situ. The POSFET device represents an integral “sensotronic” unit comprising of transducer and the transistor and are thus capable of ‘sensing and processing at same site’. The POSFET touch sensing devices are tested in a wide range (0.15-5N) of dynamic normal forces and at different frequencies.