Effect of the Channel Length on the Transport Characteristics of Transistors Based on Boron-Doped Graphene Ribbons

Abstract

Substitutional boron doping of devices based on graphene ribbons gives rise to a unipolar behavior, a mobility gap, and an increase of the ION/IOFF ratio of the transistor. Here we study how this effect depends on the length of the doped channel. By means of self-consistent simulations based on a tight-binding description and a non-equilibrium Green’s function approach, we demonstrate a promising increase of the ION/IOFF ratio with the length of the channel, as a consequence of the different transport regimes in the ON and OFF states. Therefore, the adoption of doped ribbons with longer aspect ratios could represent a significant step toward graphene-based transistors with an improved switching behavior.

A Library of Doped-Graphene Images via Transmission Electron Microscopy

“…These include (I) gas sensor by B dopant [25], transistor by B dopant [94], N dopant [40,41], NO 2 dopant [69]; (II) biosensor by N dopant [86]; (III) solar cell by HNO 3 dopant [51,52], SoCl 2 dopant [50,51], B dopant [26], HCl dopant [51], H 2 O 2 dopant [51]; (IV) fuel cell by B dopant [27], N dopant [38,96]; (V) Li-ion battery by SnO 2 /N co-dopant [35], MoS 2 /N co-dopant [36], O 2 dopant [84]; (VI) supercapacitor by N dopant [39]; (VII) FET by N dopant [44,88], diazonium salt and PEI dopants [74], NH 3 dopant [73], N 2 H 4 dopant [61,62], o-MeO-DMBI dopant [63]; (VIII) photovoltaic cells by AuCl 3 dopant [29]; electrocatalyst for ORR by S/N co-dopant [34], FeN 4 dopant [32], N dopant [37,89], P dopant [79,80], N 2 /P co-dopant [76]; (IX) PLED by TFSA dopant [48]; (X) Free-radical scavenging by P dopant [77]; and (XI) energy storage and conversion by S dopant [33]. In general, the doped-graphene exhibited the diverse potentials with physical and chemical characteristics in further improvement the unexploited and unexplored potential in graphene.…”

“…In general, the doped-graphene exhibited the diverse potentials with physical and chemical characteristics in further improvement the unexploited and unexplored potential in graphene. Plasma doping Ultracapacitor Capacitance (280 F/g), novel cycle life (>200,000), and high-power capability [39] Pyrolysis Catalyst High O-reduction reaction [43] Thermal annealing in APCVD Organic molecular sensing Novel probing of Rhodamine (RhB) molecules [40] Thermal annealing in APCVD Ultrasensitive molecular sensor Novel sensing of RhB, crystal violet (CRV), and methylene blue (MB) molecules [41] Pyrolysis Catalyst High O-reduction reaction [37] Thermal annealing in CVD Fuel cells High O-reduction reactions, long-term stability, tolerance to crossover and poison [38] Plasma doping NA NA [42] Annealing at 1100 • C Back-gate FET Mobility (6000 cm 2 /Vs) [44] Plasma doping Biosensor High electrocatalytic activity, Novel glucose biosensing with low concentration (0.01 mM) [86] Electrothermal annealing FET Highly edge functionalization of GNRs by N 2 species [87] Wet chemical doping Catalyst Good electrocatalytic activity, long term stability, and tolerance to crossover effect [88] Soft thermal doping NA NA [92,94] Solvothermal doping Fuel cell Enhanced catalytic activity in O-reduction reaction [96] Thermal annealing in APCVD NA NA [95] Obviously, the TEM is an important technique to reveal the morphology, crystalline and chemical structures of nanomaterials. The information that TEM techniques can provide and their implications on applications is based on the assistances of low-magnification TEM, HR-TEM, spherical aberration-corrected HR-TEM, BF-TEM, DP-TEM, DF-TEM, STEM, DF-STEM, STEM_EELS, HAADF-STEM, and micro EDS-TEM.…”

Contrast Transfer Function-Based Exit-Wave Reconstruction and Denoising of Atomic-Resolution Transmission Electron Microscopy Images of Graphene and Cu Single Atom Substitutions by Deep Learning Framework

“…The CDDAE framework achieved an accurate identification of substitutional atoms in graphene. The incorporation of substitutional atoms (Cr, Ti, Pd, Ni, Al, Cu, Si, B, or N) in the graphene lattice results in the etching and doping of graphene [ 27 , 28 , 29 , 30 ]. Such doping and etching by impurity atoms is useful in building novel nanostructures.…”

Theoretical Comparison between the Flicker Noise Behavior of Graphene and of Ordinary Semiconductors

“…Monolayer graphene is a recently isolated material [13] made up by a planar hexagonal lattice of carbon atoms. It is a semiconductor with a zero energy gap [14][15][16][17][18][19], even though an energy gap can be introduced, for example, by lateral confinement [20][21][22], strain [23,24], doping [25][26][27], functionalization [28,29], or introducing a lattice of antidots in the material layer [30,31]. Its dispersion relations around the degeneration points between conduction and valence bands (the so-called Dirac points, i.e., the charge neutrality points) are linear and thus in graphene charge carriers present a zero effective mass.…”