A Facile Route for Patterned Growth of Metal–Insulator Carbon Lateral Junction through One-Pot Synthesis

Abstract

Precise graphene patterning is of critical importance for tailor-made and sophisticated two-dimensional nanoelectronic and optical devices. However, graphene-based heterostructures have been grown by delicate multistep chemical vapor deposition methods, limiting preparation of versatile heterostructures. Here, we report one-pot synthesis of graphene/amorphous carbon (a-C) heterostructures from a solid source of polystyrene via selective photo-cross-linking process. Graphene is successfully grown from neat polystyrene regions, while patterned cross-linked polystyrene regions turn into a-C because of a large difference in their thermal stability. Since the electrical resistance of a-C is at least 2 orders of magnitude higher than that for graphene, the charge transport in graphene/a-C heterostructure occurs through the graphene region. Measurement of the quantum Hall effect in graphene/a-C lateral heterostructures clearly confirms the reliable quality of graphene and well-defined graphene/a-C interface. The direct synthesis of patterned graphene from polymer pattern could be further exploited to prepare versatile heterostructures.

Rapid Stencil Mask Fabrication Enabled One-Step Polymer-Free Graphene Patterning and Direct Transfer for Flexible Graphene Devices

“…, patterning and transfer) for creating interconnects, transistor channels, or device terminals have slowed the implementation of graphene in a wider range of applications 14 15 . Existing methods to pattern graphene can be categorized into conventional photolithography 16 , soft lithography or transfer printing 17 18 , direct patterning using ion beam 19 , laser scribing 20 , ablation 21 , or hydrogen desorption 22 after transfer to an appropriate substrate, and direct growth of patterned graphene 14 23 24 25 26 27 . However, despite the plethora of these aforementioned methods, they have limitations that have prevented low-cost, manufacturing of flexible graphene devices.…”

“…While nanometer-scale patterning of single layer graphene through laser ablation has been reported 21 , the process requires an expensive femtosecond laser. Finally, direct growth of patterned graphene requires the catalyst to be patterned before the growth step by the same extensive processing infrastructure as mask photolithography and/or is limited to high temperature resistance surfaces 14 23 24 25 26 27 . Furthermore, attempts to achieve one-step catalyst-free direct growth of patterned graphene on a target substrate reportedly yield subpar quality graphene 23 .…”

Large‐Area Uniform 1‐nm‐Level Amorphous Carbon Layers from 3D Conformal Polymer Brushes. A “Next‐Generation” Cu Diffusion Barrier?

“…Under the UV irradiation free radicals are generated in the backbones of the polymer chains, and adjacent chains crosslink with each other. [ 53,54 ] Thus, the thermal stability of the PS thin film was improved and the following high‐temperature treatment produced an uniform a‐C layer. [ 54–57 ] We prepared area‐selected UV irradiated samples with a shadow mask (Figure S9, Supporting Information).…”

“…[ 53,54 ] Thus, the thermal stability of the PS thin film was improved and the following high‐temperature treatment produced an uniform a‐C layer. [ 54–57 ] We prepared area‐selected UV irradiated samples with a shadow mask (Figure S9, Supporting Information). While the unexposed regions showed no Raman signal for a‐C, the UV‐exposed regions showed typical signals for a‐C, including the G (1594 cm −1 ) and D bands (1365 cm −1 ) with an I D / I G ratio of 0.60.…”

Graphene and Graphene Analogs toward Optical, Electronic, Spintronic, Green-Chemical, Energy-Material, Sensing, and Medical Applications

“…Thus, a new technique for one-pot synthesis of Gr/amorphous-carbon (a-C) heterostructures has been developed from a solid source of polystyrene via selective photo-cross-linking process (Figure b). Gr was grown from neat polystyrene regions, while the patterned cross-linked polystyrene regions turn into a-C because of a large difference in their thermal stability . CVD growth of the Gr/a-C heterostructure using cross-linking-driven chemical patterning of a solid carbon source of polystyrene has been achieved.…”