Inkjet Printing of Silver on Flexible Substrates for Sensing Applications

We report on the fabrication of a low cost sensing platform which includes printed / electroplated resistive thermometers and capacitive-based humidity sensors working at ultra low power consumption. Both types of devices were integrated on the same polymeric foil substrate. The electrodeposition of metal on the inkjetprinted lines was found to bring several advantages to the devices. For the resistors, we found a linear response of the resistance with a varying temperature range, which included environmental temperatures. This yielded a high temperature coefficient of resistance of (4.27 ± 0.02) 10-3 °C-1. The printed capacitors were coated with a Cellulose Acetate Butyrate layer and humidity sensing has been demonstrated. These results advance the concept of fabrication using only additive processes as well as the idea of, lowcost and flexible sensors for environment monitoring applications.