Printed contacts in thin film transistors (Conference Presentation)

Low-cost infrared photo-transistors with improved detectivity (i.e. higher signal-to-noise ratio) could find further use in spectral analysis, which is important for chemical identifications, as well as other applications from environmental monitoring to optical communications. Accordingly, the main goal of this research is to advance printed, flexible photo-transistors by using a family of novel donor-acceptor polymers with narrow bandgap that are responsive in the short wavelength infrared (SWIR) region. In particular, the transistors show optical response extending out to a wavelength of 1.8 micrometer. The external quantum efficiency and the rectification ratio are used to characterize the performance of devices with different polymer layer thickness, in order to optimize detectivity. The individual transistors could further be exploited for the fabrication of integrated arrays for bio-medical and/ or robotic applications. It paves the way to large-area, conformal designs that are currently not achievable with conventional inorganic SWIR materials.