Kim b, jong won lee d, ramanand gollapudi a, srinivas subramaniam c, suhasini narasimhadevara a, douglas hurd a, goutham r. Possibilities for using of the nanotubes as highcapacity hydrogen storage media were also considered. Carbon nanotube fet fabrication using ice lithography. Nanoelectronics researchers are trying to design devices that hit the sweet. The properties of cnt are important to understand for designing smart composite materials and are discussed in 2. Introduction to carbon nanotube and nanofiber smart.
Kohlenstoffnanorohrenfeldeffekttransistor wikipedia. We propose a simple fabrication technique for cntfet arrays using asgrown singlewalled cnts swnts as the gate channel. First, we focus on building a nanotube by wrapping the corresponding 2d flat structure. A common feature of the singlewalled carbonnanotube fieldeffect transistors fabricated to date has been the presence of a schottky barrier at the nanotubemetal junctions1,2,3. This paper discusses the device physics of carbon nanotube fieldeffect transistors cntfets. When maximum electric field is reduced, the gate of a fieldeffect transistor fet is able to gain control of the channel at varying drain bias. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. The basic functions of a fet are to control the device resistance or drainsource current i ds in the channel, mainly via the gate voltage v g, and to amplify signals. Kohlenstoffnanorohrenfeldeffekttransistor englisch carbon nanotube field effect transistor, cntfet ist eine weiterentwicklung des feldeffekttransistors.
However, the exact nature of the biomolecule interactions with nanotubes in these devices remains unknown, creating one of the major obstacles to their practical use. Modeling carbon nanotube fet physics in comsol multiphysics aditya. High performance ntype carbon nanotube fieldeffect. Thelower plane is the surface plot of the ir emission imagetakenunderconditions of simultaneous e and h injection into the carbon nanotube. Department of electronics and communication engineering national institute of technology, rourkela odisha, india769008 certificate this is to certify that the thesis report entitled some studies on sinanotube based fets submitted by mukesh kumar, bearing roll no. The basic computational procedure selfconsistent loop of the used quantum simulation. A carbon nanotube fieldeffect transistor cntfet refers to a fieldeffect transistor that utilizes a single carbon nanotube or an array of carbon nanotubes as the. Abstract carbon nanotubes cnts are allotropes of carbon with a nanostructure that can have a length to diameter ratio greater than 1,000,000. We assembled alternating layers of oppositely charged polyelectrolytes on the carbon nanotube. Electrically induced optical emission from a carbon. Carbon nanotube transistors for biosensing applications. The other end is doped and then contacted to the metal.
Carbon nanotube transistors are a promising platform for the next generation of nonoptical biosensors. A carbon nanotube fieldeffect transistor cntfet is a promising candidate for future electronic devices, however, the fabrication process is still challenging. An effective forwardbiased pn junction, without chemical dopants, was created in the nanotube by appropriately biasing the. If the transmission coefficient wants to be computed in the energy interval 1, 2 ev. The theoretical minimum diameter of a carbon nanotube is around 0. The carbon nanotube field effect transistor is a three terminal device similar to the mosfet. Carbon nanotubes have a range of electric, thermal, and structural properties that can change based on the physical design of the nanotube.
First demonstrated in 1998, there have been major developments in cntfets since. Carbon nanotube fets needs to include quantum effects such as tunneling. These cylindrical carbon molecules have novel properties that make them potentially useful in many applications in nanotechnology. There are n carbon atoms in each ring and a total of n. A new structure for carbon nanotube field effect transistors cntfets has been proposed recently and its currentvoltage characteristic has been simulated by zoheir kordrostami et. Tunneling phenomena in carbon nanotube fieldeffect. Pdf comparative analysis of performance characteristic of. Scientific advances in the nanotube growth process translate into commercial technical advantage 18. Carbon nanotubes are remarkable objects that look set to revolutionize the technological landscape in the near future.
The upper and the lower limit for the energy, can be specified by the user, changing the attributes eupper and elower of the instance cnt. Analysis of near ballistic carbon nanotube fieldeffect transistors. Singlewalled carbon nanotube structure singlewalled carbon nanotubes can be formed in three different designs. Electrically induced optical emission from a carbon nanotube fet. This tutorial describes how nanotube systems 1d periodicity can be simulated with the crystal code. Carbon nanotube, sheet, yarn, hybrid material, commercialization. The semiconducting channel between the two contacts called drain and source consists of the nanotube. Cgc can be calculated for n carbon nanotubes under. John hart4,5 worldwide commercialinterest in carbon nanotubes cnts is reflectedin aproduction capacity that presently. Simulations of carbon nanotube field effect transistors. Cntfets carbon nanotube field effect transistors are novel devices that.
The channel is turned onoff electrostatically via the third contact. Figure 1a shows an sem of a typical research device with metallic sourcedrain contacts and a large area backgate. Applied voltage to the gate can be control the electrical conductance of the cnt by changing electron density in the channel. In this section we will take a closer look at one particular nanostructure. Singlewalled carbon nanotubes 207 iv data recorded along the two tubes discussed earlier exhibit very different features fig. High performance ntype carbon nanotube field effect transistors. Impact of oxide thickness on gate capacitancea comprehensive analysis on mosfet, nanowire fet, and cntfet devices. Ballistic carbon nanotube fieldeffect transistors nature. A carbon nanotube fieldeffect transistor cntfet refers to a fieldeffect transistor that utilizes a single carbon nanotube or an array of carbon nanotubes as the channel material instead of bulk silicon in the traditional mosfet structure. Present and future commercial applications michael f. This report is intended to summarize some of the major achievements in the. The flake is 50 nm long, the reservoirs are 15 nm long and the channel length is 20 nm. In this study, a hydrophobic selfassembled monolayer sam.
Long channel carbon nanotube transistor cnt can be used to overcome the high electric field effects in nanoscale length silicon channel. This video illustrates the fabrication of a carbon nanotube fet using ice lithography. Schulz a, donglu shi c, jim boerio c, shankar mall e, marina ruggleswren e a smart structures. Controlled electrostatic gating of carbon nanotube fet.
One end of the carbon nanotube which forms the source is put in contact with the metal intrinsically and the other end of the cnt which forms the. The diameter of carbon nanotube can be expressed as equation 1 11. In this part we introduce the main features of nanotubes for the simple case of graphite graphene swcnt single walled carbon nanotube. In 1950, lilienfeld 6 patented the basic concept of the field effect transistor fet. Iv characteristics model for carbon nanotube field effect. In this paper, we adjust the basic parameters of cn. Carbon nanotube fet based full adder aman jain1, sukhwinder singh2 1student, 2mentor 12electronics and electrical communication department, pec university of technology, chandigarh, india abstract high speed fulladder fa module is an important element in designing high performance arithmetic circuits. Simple fabrication technique for fieldeffect transistor. A study of carbon nanotubes and their applications in.
Singlewalled carbon nanotubes lieber research group. In this paper we present an exhaustive description of the basic types of cntfets. Operation of a mosfet source and drain are created in a. The simplest case for creating a cntfet is to use the whole nanotube as a channel with a source and drain contact javey, 2003 c1. Tomorrows society will be shaped by nanotube applications, just as siliconbased technologies dominate society today. The upper plane is a colorcodedirimageofthecarbon nanotube fet.
Carbon nanotube fet fabrication using ice lithography iemediasolutions. In a conventional cntfet, the contacts between the metal electrode and the carbon nanotube channel are ohmic. One is transconductance which reflects the magnifying ability of the fet, and the other is subthreshold swing ss. The contact pads and thin wires leading to the carbonnanotubechannelare showninyellow.
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