Ultralow-Power All-Inkjet-Printed Organic Thin-Film Transistors for Wearables

Wearable electronics requires devices to have low power consumption at the same time high signal amplification capability. However, traditional device technologies do not fulfill all of these requirements. This work presents novel organic thin-film transistors (OTFT) fabricated all by an inkjet printing technology, greatly reducing fabrication cost. Devices with a Schottky barrier at the source-semiconductor contact and subthreshold operation exhibit ultralow-power
$(< \mathbf{1}\ \mathbf{nW})$
consumption with high intrinsic gain
$(> 1000\ \mathrm{V}/\mathrm{V})$
, along with good uniformity as compared to other transistor technologies. In addition, we show that by reducing device interface trap density, the subthreshold slope of the fabricated OTFTs can almost reach the thermionic limit of 60 mV/decade, with a shelf life as long as 6 months. To demonstrate its potential deployment in wearables, we present device fabrication on plastic strips so that the OTFTs can be weaved in a smart fabric and/or embedded into a stretchable fiber.