Adsorptive graphene doping: Effect of a polymer contaminant

Abstract

Transfer-induced contamination of graphene and the limited stability of adsorptive dopants are two of the main issues faced in the practical realization of graphene-based electronics. Herein, we assess the stability of HNO3, MoO3, and AuCl3 dopants upon transferred graphene with different extents of polymer contamination. Sheet resistivity measurements prove that polymer residues induce a significantly degenerative effect in terms of doping stability for HNO3 and MoO3 and a highly stabilizing effect for AuCl3. Further characterization by Raman spectroscopy and atomic force microscopy (AFM) provides insight into the stability mechanism. Together, these findings demonstrate the relevance of contamination in the field of adsorptive doping for the realization of graphene-based functional devices.

Charge transfer doping of graphene without degrading carrier mobility

“…This will cause no reduction in mobility. 34 We next consider FeCl 3 , which is also a Lewis acid like AuCl 3 . It has been used extensively as an intercalant of graphite, [35][36][37][38][39][40][41] as discussed by Li and Yue.…”

Bioelectronics and Interfaces Using Monolayer Graphene

“…[148][149][150][151] For removal of organic residues (PMMA in most cases), electron beams, gas phase cleaning, organic solvents and metal-induced catalytic decomposition have been experimented. [146,[152][153][154][155][156][157] Song and co-workers [158] reported a general method for transferring CVD-grown graphene by using a self-release polymer covered by an elastomer stamp(PDMS). The self-release polymers polystyrene (PS), poly(isobutylene) (PIB), and Teflon AF (poly[4, 5-difluoro-2,2-bis(trifluoromethyl)-1,3-dioxole-co-tetrafluoroethylene]) are inserted between the PDMS and the CVDgrown graphene transferred in such a way that the adhesion of graphene to the substrate is higher than to the self-release polymer and the elastomer.…”

“…For fundamental investigations concerning the graphene‐liquid interface, it is necessary to ensure that the graphene surface is free of any kind of residues or impurities. This is important not only to ensure the persistence of favorable electronic properties, but also to provide for an ideal sp 2 ‐carbon surface to ensure a suitable chemical interaction with functional precursors and analyte molecules . In this context, two classes of residues should be eliminated – organic residues due to the transfer process and trace metal impurities incorporated in graphene during the etching of underlying metal .…”

“…In this context, two classes of residues should be eliminated – organic residues due to the transfer process and trace metal impurities incorporated in graphene during the etching of underlying metal . For removal of organic residues (PMMA in most cases), electron beams, gas phase cleaning, organic solvents and metal‐induced catalytic decomposition have been experimented ,. Song and co‐workers reported a general method for transferring CVD‐grown graphene by using a self‐release polymer covered by an elastomer stamp(PDMS).…”