Carrier Control of Graphene Driven by the Proximity Effect of Functionalized Self-assembled Monolayers

Abstract

We demonstrated the carrier control of graphene by employing the electrostatic potential produced by several types of self-assembled monolayer (SAM) formed on SiO(2) substrates. For single layer graphene on perfluoroalkylsilane-SAM, the stiffening of the Raman G-band indicates a large down shift of the Fermi level (∼-0.8 eV) by accumulated hole carriers. Meanwhile, aminoarylsilane-SAM accumulated electron carriers, which compensate the hole carriers doped by adsorbed molecules under the ambient atmosphere, in graphene. The present results and their theoretical analysis reveal that the use of the dipole moments of SAM molecules can systematically modulate the electrostatic potential affecting graphene without destroying its intrinsic electronic structure and let us know that the proximity effect of the SAMs is a promising way in developing graphene-based solid state electronics.

Effects of Tailored Surface Chemistry on Desorption Electrospray Ionization Mass Spectrometry: a Surface-Analytical Study by XPS and AFM

“…The maximum density of silane coverage could be readily achieved with each silane, according to previously published results [36,37,44,45,53,54]. Further confirmations concerning films structures and homogeneity of the coverage were obtained by XPS.…”

“…For g-OTES, similarly to what was observed for g-MTES, C 1 s showed three major contributions at 285, 286.5, and 288 eV ( Figure 4b) and two components for the Si 2p signal at 103.0 and 103.8 eV, ascribed to Si-C and glass (Figure 4e). In the case of g-FOTES, the C 1 s signal was a convolution of five components at 285.2 eV, originating from C-C and C-Si [44][45][46], and at 286.5, 291.5, 294.0, and 288.0 eV attributable to C-O [39], -CF 2 and -CF 3 groups [39,44,45], as well as a contamination component, respectively (Figure 4c). Two components for the Si 2p signal at 102.9 and 103.7 eV were ascribed to Si-C [47,48] and glass [49], as shown in Figure 4f.…”

Formation of Air Stable Graphene p–n–p Junctions Using an Amine‐Containing Polymer Coating

“…[33][34][35][36][37][38][39][40][41][42][43][44] A critical observation is that no increase on the D band was observed after PEIE deposition; hence successful doping of the graphene monolayer without signifi cant damage to the lattice structure was achieved. [ 45,46 ] The G and 2D peaks' positions before and after PEIE deposition were monitored. Full width at half maximum of G peak, FWHM (G), and intensity ratio of 2D over G peak (I 2D /I G ) reveal the changes in electronic state of various spots on graphene FET devices.…”

Understanding and controlling the substrate effect on graphene electron-transfer chemistry via reactivity imprint lithography

“…Recently, single-crystal hexagonal boron nitride (hBN) 24,25 and self-assembled monolayers (SAMs) of hydrophobic molecules grafted on SiO 2 substrates [26][27][28][29] have been explored as alternate substrates for graphene electronics. Graphene on hBN, which is atomically smooth, chemically inert, and electrically insulating, has significantly lower electron-hole puddles and higher mobilities.…”