Characterization of inkjet-printed dielectric on different substrates

Abstract

Inkjet-printed capacitive circuits on different substrates will be investigated. This work will contribute towards rapidly prototyping electronic systems for smart ubiquitous biosensors. These biosensors require sensitive and robust signal readout with low power consumption and wireless connectivity while also being inexpensive. Capacitors were printed on different substrates, including glass and overhead projector film, to characterize an inkjet-printed dielectric. A Fujifilm Dimatix DMP2831 was used to print different functional inks, including Harima silver nanoparticle ink and InkEpo-XP ink. The silver nanoparticle ink was used to print the conductive features of the capacitors while the InkEpo-XP was used as the dielectric material. Different test patterns were printed with silver ink on the dielectric material; these patterns were used to establish a printing protocol for successful printing of silver on the dielectric material. Different test patterns were also printed with dielectric ink on silver to create a printing protocol for successfully printing dielectric on silver. Metal-insulator-metal capacitors were successfully inkjet printed on glass and overhead projector film with silver and dielectric inks. The metal-insulator-metal capacitors were used to characterize the dielectric material at different frequencies. The circuit modelling of the capacitors is discussed, and validated against experimental results. A design procedure is presented for reliably printing capacitive networks with feature dimensions between 1 mm and 2 mm on glass and overhead projector film.