External pressure responsive device based on tunable organic inverter using soft contact lamination

A voltage tunable device which operates by external pressure based on a diode-connected load inverter is successfully fabricated by connecting two transistors adopting bridge-structured polymeric stamps with gold electrodes. When pressure is applied to the polymeric stamp in the drive transistor, the effective channel length between the source–drain electrodes decreases such that the source–drain current is increased and the voltage transfer curves of the inverter are shifted in the positive direction. Thus, a voltage tunable device (or a pressure sensitive inverter) is achieved, because the output voltage of the load inverter comes to have a corresponding relation with the applied pressure. In addition, the sensitivity of this pressure responsive device can be improved by changing the thickness of the polymeric stamp.