Numerical simulations are used to guide the development of a simple analytical theory for ballistic field-effect transistors. When two-dimensional (2-D) electrostatic effects small (and when insulator capacitance is much less than semiconductor (quantum) capacitance), model reduces Natori's MOSFET. The also treats 2-D electrostatics and quantum limit where capacitance. This new provides insights into performance MOSFETs near scaling unified framework assessing comparing variety novel

Although carbon nanotube (CNT) transistors have been promoted for years as a replacement silicon technology, there is limited theoretical work and no experimental reports on how nanotubes will perform at sub-10 nm channel lengths. In this manuscript, we demonstrate the first CNT transistor, which shown to outperform best competing devices with more than four times diameter-normalized current density (2.41 mA/μm) low operating voltage of 0.5 V. The transistor exhibits an impressively small...

Single walled carbon nanotubes with Pd Ohmic contacts and lengths ranging from several microns down to 10 nm are investigated by electron transport experiments theory. The mean-free path (MFP) for acoustic phonon scattering is estimated be ${l}_{\mathrm{ap}}\ensuremath{\sim}300\text{ }\text{ }\mathrm{nm}$, that optical ${l}_{\mathrm{op}}\ensuremath{\sim}15\text{ }\mathrm{nm}$. Transport through very short ($\ensuremath{\sim}10\text{ }\mathrm{nm}$) free of significant thus ballistic...

A simple one-flux scattering theory of the silicon MOSFET is introduced. Current-voltage (I-V) characteristics are expressed in terms parameters rather than a mobility. For long-channel transistors, results reduce to conventional drift-diffusion theory, but they also apply devices which channel length comparable or even shorter mean-free-path. The indicate that for very short channels transconductance limited by carrier injection from source. indicates evaluation drain current short-channel...

Black phosphorus has been revisited recently as a new two-dimensional material showing potential applications in electronics and optoelectronics. Here we report the anisotropic in-plane thermal conductivity of suspended few-layer black measured by micro-Raman spectroscopy. The armchair zigzag conductivities are ~20 ~40 W m$^{-1}$ K$^{-1}$ for films thicker than 15 nm, respectively, decrease to ~10 film thickness is reduced, exhibiting significant anisotropy. ratio found be ~2 thick drops...

The device physics of nanoscale MOSFETs is explored by numerical simulations a model transistor. charge control, source velocity saturation due to thermal injection, and scattering in ultrasmall devices are examined. results show that the essential can be understood terms conceptually simple model.

High-performance enhancement-mode semiconducting carbon nanotube field-effect transistors (CNTFETs) are obtained by combining ohmic metal−tube contacts, high-dielectric-constant HfO2 films as gate insulators, and electrostatically doped segments source/drain electrodes. The combination of these elements affords high ON currents subthreshold swings ∼70−80 mV/decade allows for low OFF suppressed ambipolar conduction. source drain approach resembles that MOSFETs can impart excellent states to...

According to Moore9s law, the number of transistors on a chip should double in each technology generation. For more than 30 years, compliance with this law has been driven by shrinking transistor dimensions. But as Lundstrom explains his Perspective, device physics and limitations existing materials pose restrictions how far dimensions can be reduced. may nevertheless survive as engineers build layers devices chips or use new approaches such molecular electronics.

In this article, we present a computationally efficient, two-dimensional quantum mechanical simulation scheme for modeling electron transport in thin body, fully depleted, n-channel, silicon-on-insulator transistors the ballistic limit. The proposed scheme, which solves nonequilibrium Green’s function equations self-consistently with Poisson’s equation, is based on an expansion of active device Hamiltonian decoupled mode space. Simulation results from method are benchmarked against solutions...

Carbon nanotube field-effect transistors with structures and properties near the scaling limit short (down to 50 nm) channels, self aligned geometries, palladium electrodes low contact resistance high-k dielectric gate insulators are realized. Electrical transport in these miniature is ballistic up high biases at both room temperatures. Atomic layer deposited (ALD) films interact sidewalls via van der Waals interactions without causing weak localization 4 K. New fundamental understanding of...

The silicon nanowire transistor (SNWT) is a promising device structure for future integrated circuits, and simulations will be important understanding its physics assessing ultimate performance limits. In this work, we present three-dimensional quantum mechanical simulation approach to treat various SNWTs within the effective-mass approximation. We begin by assuming ballistic transport, which gives upper limit of devices. use mode space (either coupled or uncoupled) produces high...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> We aim to provide engineers with an introduction the nonequilibrium Green's function (NEGF) approach, which is a powerful conceptual tool and practical analysis method treat nanoscale electronic devices quantum mechanical atomistic effects. first review basis for traditional, semiclassical description of carriers that has served device more than 50 years. then describe why this traditional...

In this paper, we present a detailed performance comparison between conventional n-i-n MOSFET transistors and tunneling field-effect (TFETs) based on the p-i-n geometry, using semiconducting carbon nanotubes as model channel material. Quantum-transport simulations are performed nonequilibrium Green's function formalism considering realistic phonon-scattering band-to-band mechanisms. Simulations show that TFETs have smaller quantum capacitance at most gate biases. Despite lower on-current,...

We performed a comprehensive scaling study of Schottky barrier carbon nanotube transistors using self-consistent, atomistic scale simulations. restrict our attention to FETs whose metal source/drain is attached an intrinsic channel. Ambipolar conduction found be important factor that must carefully considered in device design, especially when the gate oxide thin. The channel length limit imposed by source-drain tunneling between 5nm and 10nm, depending on off-current specification. Using...

A program to numerically simulate quantum transport in double gate metal oxide semiconductor field effect transistors (MOSFETs) is described. The uses a Green's function approach and simple treatment of scattering based on the idea so-called Buttiker probes. device geometry permits an efficient mode space that dramatically lowers computational burden use as design tool. Also implemented for comparison are ballistic solution Boltzmann equation drift-diffusion approaches. described some...

The upper limit performance potential of ballistic carbon nanoribbon MOSFETs (CNR MOSFETs) is examined. Calculation the bandstructure nanoribbons using a single p <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">z</sub> -orbital tight-binding method and evaluation current-voltage characteristics MOSFET were used in semiclassical model. authors find that semiconducting ribbons few nanometers width behave electronically manner similar to nanotubes,...

Multiscale simulation approaches are needed in order to address scientific and technological questions the rapidly developing field of carbon nanotube electronics. In this paper, we describe an effort underway develop a comprehensive capability for multiscale We focus paper on one element that hierarchy, ballistic CNTFETs by self-consistently solving Poisson Schrödinger equations using nonequilibrium Green's function (NEGF) formalism. The NEGF transport equation is solved at two levels: i)...

Performance limits of silicon MOSFETs are examined by a simple analytical theory augmented self-consistent Schrodinger-Poisson simulations. The on-current, transconductance, and drain-to-source resistance in the ballistic limit (which corresponds to channel length approaching zero) examined. transconductance that oxide thickness approaches zero is also results show as limit), on-current approach finite limiting values minimum value. source velocity can be high about 1.5/spl times/10/sup 7/...

The dependence of the linear and saturated drain current a nanoscale MOSFET on near-equilibrium, inversion layer mobility long-channel device from same technology is examined. Simple expressions developed scattering theory provide quantitative relation between short-channel current. explains commonly observed mobility-dependence currents in present-day deep submicron MOSFETs, results can be extrapolated all way to ballistic limit.

A numerical method for analyzing heterostructure semiconductor devices is described. The macroscopic equations materials with position-dependent dielectric constant, bandgap, and densities-of-states are first cast into a form identical to that commonly used model heavily doped semiconductors. Fermi-Dirac statistics also included within this simple, Boltzmann-like formulation. Because of the similarity in formulation employed semiconductors, well-developed techniques can be directly applied...