Photo-Induced Doping in a Graphene Field-Effect Transistor with Inkjet-Printed Organic Semiconducting Molecules.

Nikita Nekrasov,Aleksei Emelianov,Ivan Bobrinetskiy,Dmitry Kireev,Nejra Omerović

doi:10.3390/nano9121753

Abstract

In this work, we report a novel method of maskless doping of a graphene channel in a field-effect transistor configuration by local inkjet printing of organic semiconducting molecules. The graphene-based transistor was fabricated via large-scale technology, allowing for upscaling electronic device fabrication and lowering the device’s cost. The altering of the functionalization of graphene was performed through local inkjet printing of N,N′-Dihexyl-3,4,9,10-perylenedicarboximide (PDI-C6) semiconducting molecules’ ink. We demonstrated the high resolution (about 50 µm) and accurate printing of organic ink on bare chemical vapor deposited (CVD) graphene. PDI-C6 forms nanocrystals onto the graphene’s surface and transfers charges via π–π stacking to graphene. While the doping from organic molecules was compensated by oxygen molecules under normal conditions, we demonstrated the photoinduced current generation at the PDI-C6/graphene junction with ambient light, a 470 nm diode, and 532 nm laser sources. The local (in the scale of 1 µm) photoresponse of 0.5 A/W was demonstrated at a low laser power density. The methods we developed open the way for local functionalization of an on-chip array of graphene by inkjet printing of different semiconducting organic molecules for photonics and electronics.

Highlights

Hybrid organic/inorganic heterostructures have become highly engaging materials, providing novel properties in electrical conduction, optical responsivity, and flexibility, and generating novel technology for their production, paving the way for a new class of hybrid functional materials whose final properties can be selected by careful molecular design [1,2]
Perylene diimide (PDI) chromophore derivatives have been successfully introduced for non-covalent functionalization of graphene in tasks of exfoliation, stabilization of graphene solutions, uniform decoration by other nanoparticles, thin film preparation, increasing the thermal properties of composites, drug delivery, and novel optoelectronic devices [10]
PDI interacts with graphene via π–π stacking with strong chemical doping by charge transfer that can be either p-type [11] or n-type [12] depending on radicals attached to PDI

Summary

Introduction

Hybrid organic/inorganic heterostructures have become highly engaging materials, providing novel properties in electrical conduction, optical responsivity, and flexibility, and generating novel technology for their production, paving the way for a new class of hybrid functional materials whose final properties can be selected by careful molecular design [1,2]. Inkjet printing performs accurate positioning of down to picolitre drops of semiconducting organic materials with resolution in about the tens of micrometres [17] This technique was used to develop printed products by manufacturing large-area organic electronics with comparable performances to the traditional methods [18]. This work reports on the maskless method of hybrid photosensitive junction fabrication in a graphene field-effect transistor (GFET) based on the inkjet printing of semiconducting organic ink. The suggested method of junction formation in GFET is a prospective approach for a non-covalent functionalization of an array of graphene-based transistors by different organic molecules for photonic and electronic device fabrication

Graphene Growth and GFET Fabrication

Organic Semiconductors Ink Preparation

Ink-Jet Printing

Graphene FET Characterization

Photoresponse Measurements

Non-Covalent Functionalization of Graphene by an Array of Organic Molecules