Photosensitive junctions based on UV-modified graphene and inkjetprinted organic molecules

In this work, we report a novel method of mask-less doping of graphene channel in field-effect transistor configuration

by local inkjet printing of organic semiconducting molecules. Graphene-based transistor was fabricated via large-scale

technology, allowing for upscaling electronic device fabrication and lowering the device cost. The altering of

functionalization of graphene was performed through local inkjet printing of semiconducting molecules: N,N′-Dihexyl-

3,4,9,10-perylenedicarboximide (PDI-C6), 5,5′′′-Dihexyl-2,2′:5′,2′′:5′′,2′′′-quaterthiophene (HEX-4T-HEX) and

polyalanine (PANI). We found the effect of UV treatment on fabrication of graphene/organic junctions because of

change in graphene hydrophobic properties. We demonstrated the high resolution (about 50 μm) and accurate printing of

organic ink on UV treated chemical vapor deposited (CVD) graphene. The PANI/graphene junction demonstrate more

stable photoresponse characteristic for 470 nm diode illumination. The characteristics of PDI/graphene junction

demonstrate the saturation for high diode power because of organic crystals degradation. The photoresponse of 1 mA/W

was demonstrated for PANI/graphene junction at 0.3 V bias voltage. The developed method opens the way for local

functionalization of on-chip array of graphene by inkjet printing of different semiconducting organic molecules for

photonics and electronics application.