  The contact resistance limits the down-scaling and operating range of OFETs.
With the monolayer (1L) organic crystals and non-destructive
metal/semiconductor interfaces, intrinsic mobility of 12.5 cm2V-1s-1 and Ohmic
contact resistance of 40 ohm-cm were achieved. The on/off ratio maintained at
10^3 even at a small VDS of -0.1 mV. High current density of 4.2 uA/um was
achieved with the 1L-crystal as the active layer. At such high current density,
the velocity saturation and channel self-heating effects are observed in OFETs
for the first time. In addition to the low contact resistance and
high-resolution lithography, we suggest the thermal management of the high
mobility OFETs will be the next major challenge to achieve high-speed densely
integrated flexible electronics.
