GRAPHENE NANORIBBONS FET

Maruful AlamLinun nahar tania

ContentWhat is Graphene?HistoryEvaluation of Graphene FET Advantages of GrapheneWhat is GNR FET?Application of GNR FETConclusion

WHAT IS GRAPHENE ?Graphene is the world’s first 2d

crystal.Graphene is a thin layer of pure

carbon and a single tight packed layer of carbon atom

It’s a single layer of hexagonal honeycomb structure

It’s thinnest known material only 1 atom thick.

Graphite itself consist of many graphene sheets stacked together

HISTORY One of the very first patents pertaining to the production

of graphene was filed in October, 2002 entitled, "Nano-scaled Graphene Plates“. 

 Two years later, in 2004 Andre Geim and Kostya Novoselov at University of Manchester extracted single-atom-thick crystallites from bulk graphite 

 Geim and Novoselov received several awards for their pioneering research on graphene, notably the 2010 Nobel Prize in Physics.

EVALOUTION OF GRAPHENE FET

Structure and evaluation of GNR FETA 300-nm SiO2 layer underneath the graphene served as a

back-gated dielectric and a doped silicon substrate acted as the back-gate. Such back-gate device have been very useful for proof-of-concept purpose, but they suffer from unacceptably large parasitic capacitances and can not be integrated with other components. Therefore practical GNR FET need a top-gate.

Schematics of different graphene MOSFET types: back-gated MOSFET (left); top-gated MOSFET with a channel of exfoliated graphene or of graphene grown on metal and transferred to a SiO2-covered Si wafer (middle); top-gated MOSFET with an epitaxial-graphene channel (right). The channel shown in red can consist of either large-area graphene or graphene nanoribbons. b, Progress in graphene MOSFET development compared with the evolution of nanotube FET.

ADVANTAGES OF GRAPHENEHigher electron mobilitySuperb electron & heat conductivity , grater than copperStronger than diamond and steel Can be used to make anti bacterial materials as well as

biodevicesVery less break over voltage , less than 0.3 v

GRAPHENE NANORIBBON FET

nanoribbons (also called nano-graphene ribbons or nano-graphite ribbons), often abbreviated GNRs, are strips of graphene with ultra-thin width (<50 nm). Graphene ribbons were introduced as a theoretical model by Mitsutaka Fujita and coauthors to examine the edge and nanoscale size effect in graphene

GNR FET APPLICATIONSRoom-Temperature High On/Off Ratio in Suspended GNRFET This work shows for the first time that ambipolar field effect characteristics and high on/off ratios at

room temperature can be achieved in relatively wide graphene nanoribbon (15 nm ~50 nm) by controlled current annealing.

we used controlled current annealing to create a narrow constriction in the suspended GNR to open a confinement gap at room temperature.

(AFM) was used to confirm the formation of a narrow constriction in the GNRs

Fig.1. AFM images of typical FET devices consisting of a GNR contacted by Au electrodes before (a) and

after (b) suspending the GNR. (c) Line profile of the top section of the suspendedGNR.

Fig. 2. Electrical transport properties of a representative suspended GNR FET device measured at room temperature, where the suspended GNR is 21±3 nm wide, ~1.4 nm thick and ~600 nm long. (a) Transfer characteristic of the device after current annealing to a predefined bias voltage set-point of 2.9 V. (b) I-V characteristics of the device measured at various gate voltages ranging from -15 to 15 V. (c) Transfer characteristic measured after various degrees of current annealing.(d) Current versus gate voltage (Vg) measured at different bias voltages after the final stage of current annealing (annealed to 3.05 V).

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GNRFET APPLICATION Current-voltage characteristics of a

graphene nanoribbon field-effect transistor

The operation of G-FETs is accompanied by the formation of the lateral n-p-n (or p-n-p) junction under the controlling (top) gate and the pertinent energy barrier.

The model can be used for the GNR-FET optimization.

FIG. 1: Schematic side (a) and top (b) views of a GNR-FET structure.

Other applications:Others application are : #Graphene nanoribbon field-effect

transistors on wafer-scale epitaxial 

#Graphene nano-ribbon field-effect transistors as future low-power devices

#Device Performance of Graphene Nanoribbon Field-Effect Transistors in the Presence of Line-Edge Roughness

#Graphenenanoribbons could be a way to construct ballistic transistors

Conclusion High-power high frequency electronic

devicesImproved conductivity of materialsIncreasing the efficiency of electric batteries

by use of graphene powderImaginary flexible cell phone screens will be thin as wallpaper that it

could roll up and take with you.GNR could easily remove salt from the

water.

Referrence

Room-Temperature High On/Off Ratio in Suspended Graphene Nanoribbon Field EffectTransistors

Ming-Wei Lin1,*, Cheng Ling1,*, Yiyang Zhang1,2, Hyeun Joong Yoon2, Mark Ming-Cheng

Cheng2, Luis A. Agapito3, Nicholas Kioussis3, Noppi Widjaja1, and Zhixian Zhou1, a)

1Department of Physics and Astronomy, Wayne State University,Detroit, MI 482012Department of Electrical and computer engineering, Wayne

State University,Detroit, MI 482023Department of Physics, California State University, Northridge,

CA 91330

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6629286&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6629286

Refference

Tunneling Current-Voltage Characteristics ofGraphene Field-EfectTransistor

Victor Ryzhii1;3, Maxim Ryzhii1;3, and Taiichi Otsuji2;31Computer Solid State Physics Laboratory, University

of Aizu, Aizu-Wakamatsu, 965-8580, Japan2 Research Institute for Electrical Communication,

Tohoku University, Sendai, 980-8577, Japan3Japan Science and Technology Agency, CREST, Tokyo

107-0075, Japanhttp://www.researchgate.net/publication/239005965