Spice compatible cnt interconnect and cntfet models in veriloga hardware description language are presented in this paper. Carbon nano tube cnt and carbon nano tube field effect transistor cntfet carbon nano tube cnt has been considered as one of the most important building blocks in nano devices. 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. This deterministic approach has at its core the law of mass action, an empirical law giving a simple relation between. In order to effectively simplify the simulation of cntfet, an accurate numerical model for charge density in cntfets is proposed in this paper based on ballistic transport theory dang, 2006. Comparing stochastic simulation and odes modelling challenges background the modelling of chemical reactions using deterministic rate laws has proven extremely successful in both chemistry and biochemistry for many years. Dynamic simulation of cntfetbased digital circuits international. The basic assumption here is mosfet like cntfet, where the schottky. Section ii describes the carbon nanotube structure and its physical properties. In this paper, a veriloga formulation of the stanford compact model is used for the simulation of different logic gates in. For simulating the mosfet circuits we used tsmc spice modelbsim3 v3.
Pass transistor logic often uses fewer transistors, runs faster, and requires less power than the same function implemented with the same transistors in fully complementary cmos logic. Design and simulate ternary multiplier based cntfet a. This paper enumerates the efficient design and analysis of ntype cntfet based 2x1 multiplexer. Cntfet basics and simulation, in design and test of integrated systems in na noscale technology, ieee. 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. A conclusion is that the tube diameter influences not only the current level, but also the threshold voltage of the cntfet, while. Modelling and characterization of cntfet using hspice. Cntfet basics and simulation ieee conference publication. Leveugle, cntfet basics and simulation, ieee trans.
Nanotube field effect transistor cntfet is the most promising technology to extent due to three reasons. Lecture notes on simulation and modeling course content. A fast, numerical circuitlevel model of carbon nanotube. The behavior of a system that evolves over time is studied by developing a simulation model. This model has a minimum possible channel length of 10nm and a width of 4nm. Msc in electronic, faculty of technical engineering, fasa branch, islamic azad university, fars, iran 2. This has led to problems such as an inability to calculate systems that require a large model or a loss of accuracy due to use. Introduction to rf simulation and its application characteristics of rf circuits 4 of 47 the designers guide community 2. We also discuss the electrical and vi char acteristics of cntfet. If you are just starting out, you might want to copy a demo file to your own directory and edit the netlist to create your own circuit.
Design and simulate ternary multiplier based cntfet. Cntfet and types of cntfet are discussed in section 2. In this paper we present an exhaustive description of the basic types of cntfets. Simulations of carbon nanotube field effect transistors. The cntfet is a field effect transistor in which carbon nano tubecnt is used in the. The performance of cntfet inverters, bscmig inverters and conventional mosfet inverters. Design and analysis of ntype cntfet based 2 x 1 multiplexer. This introduction to simulation tutorial is designed to teach the basics of simulation, including structure, function, data generated, and its proper use. Simulation resultsand comparative analysis cntfets can be used as inverter by connecting p type and n type cntfets in series as shown in figure1 9. Implementation of mod16 counter using veriloga model of.
Simulation results we used hspice to obtain the operational characteristics of the cntfet at different device parameters. So, to obtain predictive circuit simulation results, it is mandatory to precisely understand transport phenomena in cntfet at the molecular scale. Request pdf cntfet basics and simulation this paper provides an overview of current types of cntfets and of some compact models. Hence, considering a single walled, semiconducting carbon nanotube as the channel of a cntfet including source, drain, gate electrodes, the. The simulation approach because the twosample ttest is simple, well rst explore simulation for power for that scenario to compare the simulation approach to the analytic approach. Accurate spice compatible cnt interconnect and cntfet. Simulation and synthesis techniques for asynchronous fifo. For this simulation we have kept all other parameters fixed and changed the channel length as well as the top gate length proportionally. Modeling and simulation of ntype carbon nanotube field effect transistors using. This paper provides an overview of current types of cntfets and of some compact models. Design methodology based on carbon nanotube field e. It is a 2d fast monte carlo simulator which can take into account all the relevant quantum effects, thank to the implementation of the bohm effective potential method. Secondly we have changed the diameter, by changing the chirality, and kept the channel length constant. The tspc d flip flop and shift registers are designed using stanford university cntfet model and proposed 10nm cntfet model with sleepy keeper low power technique.
First we simulated a cntfet where a 10,0 cnt is used as channel. We have then studied the effect of channel length and chirality on the drain current for planer cntfet. Highperformance carbon nanotube field effect transistors with. Box 700747, 151 engineers way 601 university drive 6. A tunneling carbon nanotube field effect transistor with asymmetric graded double halo asymgdht cntfet is investigated in order to enhance band to band tunneling and evaluate the device characteristics by nonequilibrium greens function negf method.
Also, the simulation results, conclude that the cntfetbased proposed dmfps can perform in a wide range of frequency with minimum chip area in compare to the other stateofthe art dmfps and the presented structures have a better fom 2 criterion than the other dmfps for the similar frequency ranges under the same conditions in 32 nm technology. Hspice basics an input netlist file must be created to begin the design entry and simulation process. Computer simulation as a tool for analyzing and optimizing reallife processes management information systems vol. A simplied introduction to circuit simulation using spice opus.
Pdf implementation of mod16 counter using veriloga. In section 4, we summarize all the challenges from the designers perspective. The conclusion is that the tube diameter influences not only the current level, but also the. A model construct a conceptual framework that describes a system. Archimedes is the gnu package for the design and simulation of submicron semiconductor devices. The possibility of creating a simulation model in a general programming language is not popular. Modeling and simulation fundamentals encompasses a comprehensive study of the discipline and is an excellent book for modeling and simulation courses at the upperundergraduate and graduate levels. Mosfets with cntfets to overcome all the limitations of silicon mosfets. Cntfet basics and simulation request pdf researchgate. Analysis of the operational characteristics of cntfet. Cntfet and cmos are similar, therefore the cntfet can use the fundaments of cmos design. Vhdlams implementation of a numerical ballistic cnt model. Section iii presents the cnt fet model and its equivalent circuit and section iv presents the simula tion results of cntfet model using hspice as well as matlab.
Cntfet is defined as gate to source voltage, which is. Since most simulation results are essentially random variables, it may be hard to determine whether an observation is a result of system interrelationships or just randomness. Recently proposed circuitlevel models of carbon nanotube transistor cnt for spicelike simulators suffer from numerical complexities as they rely on numerical evaluation of integrals or internal newtonraphson iterations to find solutions of. The cntfet simulation will be carried out by cntfet lab tool of 4, which is an. In times to come, greater volumes of data be collected and analyzed than ever before, and the. Cntfets roberto marani and anna gina perri electronic devices laboratory, electrical and information engineering department, polytechnic university of bari, via e.
It is an ascii text le created using any text editor. Carbon nanotube field effect transistor cntfet has a wide scope in the field of nanotechnology. Faculty of technical engineering, fasa branch, islamic azad university, fars, iran. Ijiima in 1991 while performing some experiments on molecular structure composed of carbonium 1. Design of low threshold full adder cell using cntfet. Cntfet is found to be one of the most promising alternatives for mosfet. Simulation is a powerful tool if understood and used properly. Muniraj 1research scholar, department of ece, karpagam university, coimbatore 2principal, tejaa shakthi institute of technology for women, coimbatore. Simulation and synthesis techniques for asynchronous fifo design clifford e. Generation of artificial history and observation of that observation history.
Data analysis and simulation the widespread availability of inexpensive computing power is having a major impact on data analysis. Design of universal logic gates based on cntfet for binary and ternary logic 1radha tapiawala, 2rahul kashyap 1,2department of electronics and communication engineering vlsi and embedded system design gujarat technological university, ahmedabad, india and. These devices show the ballistic transport in the current conduction. Monte carlo simulation, discreteevent simulation, continuous system simulation, mixed continuousdiscreteevent simulation. We present a physical compact model of a dual gate carbon nanotube field effect transistor dg cntfet. Using the available models, the influence of the parameters on the device characteristics was simulated and analyzed. The selfconsistent potential of cntfet is an important element in determining device current. Simulation and analysis of cntfets based logic gates in hspice. This paper enumerates the efficient design and analysis of low power cntfet true single phase clock logic d flip flop based shift registers. Simulation and analysis of cntfets based logic gates in. The value of the simulation approach is that it scales better with analytic complexity, so starting simple may seem like a waste of time. A simplied introduction to circuit simulation using spice opus 7 figure 2. The cntfet is emerging as a viable replacement to the mosfet.
Design of universal logic gates based on cntfet for binary. 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. Cntfets carbon nanotube field effect transistors are novel devices that are expected to sustain. Tunneling carbon nanotube field effect transistor with. Cntfets and mosfets is that the channel of the devices is formed by carbon nanotubes cnts instead of silicon, which enables a higher drive current density, due to the larger current carrier. Xor has the worstcase karnaugh mapif implemented from simple gates, it requires more transistors than any other function. In this paper we propose a simulation study to carry out dynamic analysis of cntfetbased digital circuit, introducing in the semiempirical compact model for cntfets. In this paper we implement a simple dc model for cntfets already proposed by us in order to carry out static analysis of basic digital circuits. This paper is an introduction to rf simulation methods and how they are applied to make common rf measurements.
Design methodology based on carbon nanotube field effect. Carbon nanotubes field effect transistors cntfets are one of the most promising. Simulation and analysis of cntfet based inverter gaurav sapra university institute of engineering and technology u. Design and analysis of low power cntfet tspc d flip flop. Simulation and analysis of cntfets based logic gates in hspice 1neetu sardana, 2l. The multiplexer is designed using ballistic cntfet vhdlams model with the dcnt of 1nm in resistive load inverter logic. Metallic cnts are shown to have current saturation characteristics above a threshold voltage and then modelled with piecewise linear functions.
We used stanford university cntfet model package v221. We address the changes and challenges finfets have introduced for circuit design in section 3. Using the available models, we simulated and analyzed the influence of the parameters on the device characteristics. A simulation is the imitation of the operation of realworld process or system over time. A conclusion is that the tube diameter influences not only the current level, but also the threshold voltage of the cntfet, while the contact resistance influences only the current level. It is also a valuable reference for researchers and practitioners in the fields of computational statistics, engineering, and computer science who. Generation of artificial history and observation of that observation history a model construct a conceptual framework that describes a system the behavior of a system that evolves over time is studied by developing a simulation model.
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