Related papers: Observation of Negative Contact Resistances in Gra…
Contact Resistance (RC) is a major limiting factor in the performance of graphene devices. RC is sensitive to the quality of the interface and the composition of the contact, which are affected by the graphene transfer process and contact…
We study the contact resistance and the transfer characteristics of back-gated field effect transistors of mono- and bi-layer graphene. We measure specific contact resistivity of ~7kohm*um2 and ~30kohm*um2 for Ni and Ti, respectively. We…
We study the ballistic transmission and the contact resistance ($R_c$) of a graphite-graphene contact in a top contact geometry from first principles. We find that the calculated $R_c$'s depend on the amount of graphene-graphite overlap,…
Graphene field-effect transistors with source/drain contacts made of metals that can be easily oxidized such as ferromagnetic metals often display a double dip structure in the transfer characteristics because of charge density depinning at…
Metal contacts have been identified to be a key technological bottleneck for the realization of viable graphene electronics. Recently, it was observed that for structures that possess both a top and a bottom gate, the electron-hole…
The extremely high carrier mobility and the unique band structure, make graphene very useful for field-effect transistor applications. According to several works, the primary limitation to graphene based transistor performance is not…
In this work, we clarify the physical mechanism for the phenomenon of negative output differential resistance (NDR) in short-channel graphene FETs (GFETs) through non-equilibrium Green's function (NEGF) simulations and a simpler…
The contact properties between metal and graphene were examined. The electrical measurement on a multiprobe device with different contact areas revealed that the current flow preferentially entered graphene at the edge of the contact metal.…
In this work, we present an investigation regarding how and why molecular hydrogen changes the electronic properties of graphene field effect transistors. We demonstrate that interaction with H2 leads to local doping of graphene near of the…
Negative differential resistance (NDR) with room temperature peak-valley-ratio of 8 has been observed in a ballistic field-effect-transistor (FET) based on graphene, having an oblique top gate. Graphene FETs with a top gate inclination…
An anomalous distortion is often observed in the transfer characteristics of graphene field-effect transistors. We fabricate graphene transistors with ferromagnetic metal electrodes, which reproducibly display distorted transfer…
We report a systematic study of the bias-dependent contact resistance in rubrene single-crystal field-effect transistors with Ni, Co, Cu, Au, and Pt electrodes. We show that the reproducibility in the values of contact resistance strongly…
Graphene has attracted much attention as one of promising candidates of future high-speed transistor materials because of its high carrier mobility of more than 10,000 cm2 V-1 s-1. Up to this point, we have focused on the contact properties…
The metal-graphene contact resistance is one of the major limiting factors toward the technological exploitation of graphene in electronic devices and sensors. A high contact resistance can be detrimental to device performance and spoil the…
Graphene field-effect transistors exhibit negligible transconductance under two scenarios: for any gate-to-source voltage when the drain-to-source voltage is set to zero, and for an arbitrary drain-to-source voltage provided that the…
The Dirac voltage of a graphene field-effect transistor (GFET) stands for the gate bias that sets the charge neutrality condition in the channel, thus resulting in a minimum conductivity. Controlling its dependence on the terminal biases is…
We have performed scanning gate microscopy (SGM) on graphene field effect transistors (GFET), using a biased metallic nanowire coated with a dielectric layer as a contact mode tip and local top gate. Electrical transport through graphene at…
Graphene field-effect transistors with Co contacts as source and drain electrodes show anomalous distorted transfer characteristics. The anomaly appears only in short-channel devices (shorter than approximately 3 micrometers) and originates…
Edge contact geometries are thought to yield ultralow contact resistances in most non-ferromagnetic metal-graphene interfaces owing to their large metal-graphene coupling strengths. Here, we examine the contact resistance of edge- versus…
The performance of graphene-based transistors is often limited by the large electrical resistance across the metal-graphene contact. We report an approach to achieve ultra-low resistance metal contacts to graphene transistors. Through a…