Inkjet printing of microsensors

In the past few years, inkjet printing of microelectronics has been emerging as a cost effective and an environment friendly microfabrication technique. In this paper, inkjet printing of microsensors is investigated, using both resistive and capacitive strain-sensing operating devices. An inexpensive conductive polymer, poly(3,4-ethylenedioxythiophene) oxidized with poly(styrenesulfonate) (PEDOT:PSS) is used as base material for inkjet printing. The experimental characterization shows that the PEDOT:PSS preserves its piezoresistive properties after being printed in thin film patterns, leading to large gauge factors. Stress sensitive interdigitated capacitors fabricated through inkjet printing have as well a high sensitivity and are reported, to our knowledge, for the first time.