Organic Thin Film Transistors Incorporating Recessed Electrodes on Polymer Gate Dielectric

The solution-processed inverted co-planar organic thin film transistor (OTFT) incorporating recessed source-drain-gate and polymer gate dielectric is demonstrated to realize a fully recessed device. The impact of recessed electrodes on the contact resistance ( R-{c} ) and the mobility ( \mu ) is thoroughly investigated by comparing the performance of fully recessed devices, partially recessed (source-drain) devices and standard non-recessed devices. A reduction in R-{c} by two orders of magnitude and 3-fold increase in \mu to attain the values of 60 k\Omega -cm (without any surface treatment) and 1.5\times 10^{-2}cm^{2}/Vs respectively are achieved in a fully recessed device as compared to the standard non-recessed device.