19 May 2006 | Tools | Contributor(s): Zhibin Ren, Sebastien Goasguen, Akira Matsudaira, Shaikh S. Ahmed, Kurtis Cantley, Yang Liu, Yunfei Gao, Xufeng Wang, Mark Lundstrom
2-D simulator for thin body (less than 5 nm), fully depleted, double-gated n-MOSFETs
Band Structure Lab
19 May 2006 | Tools | Contributor(s): Samik Mukherjee, Kai Miao, Abhijeet Paul, Neophytos Neophytou, Raseong Kim, Junzhe Geng, Michael Povolotskyi, Tillmann Christoph Kubis, Arvind Ajoy, Bozidar Novakovic, James Fonseca, Hesameddin Ilatikhameneh, Sebastian Steiger, Michael McLennan, Mark Lundstrom, Gerhard Klimeck
Computes the electronic and phonon structure of various materials in the spatial configuration of bulk , quantum wells, and wires
Nanoscale Transistors: Advanced VLSI Devices (Introductory Lecture)
20 Apr 2006 | Online Presentations | Contributor(s): Mark Lundstrom
Welcome to the ECE 612 Introductory/Overview lecture. This course examines the device physics of advanced transistors and the process, device, circuit, and systems considerations that enter into the development of new integrated circuit technologies.
30 Mar 2006 | Tools | Contributor(s): Dragica Vasileska, Shaikh S. Ahmed, Gokula Kannan, Matteo Mannino, Gerhard Klimeck, Mark Lundstrom, Akira Matsudaira, Junzhe Geng
SCHRED simulation software calculates the envelope wavefunctions and the corresponding bound-state energies in a typical MOS, SOS and a typical SOI structure.
A Primer on Semiconductor Device Simulation
23 Jan 2006 | Online Presentations | Contributor(s): Mark Lundstrom
Computer simulation is now an essential tool for the research and development of semiconductor processes and devices, but to use a simulation
tool intelligently, one must know what's "under the hood." This talk
is a tutorial introduction designed for someone using semiconductor
device simulation for the first time. After reviewing the
semiconductor equations, I will briefly describe how one solves them
"exactly" on a computer. I'll then discuss an example device
simulation program and conclude with some thoughts about how to
effectively use simulation in practice.
A Top-Down Introduction to the NEGF Approach
14 Jun 2004 | Online Presentations | Contributor(s): Mark Lundstrom
A Top-Down Introduction to the NEGF Approach
Homework for PN Junctions: Depletion Approximation (ECE 305)
06 Jan 2006 | Teaching Materials | Contributor(s): Mark Lundstrom, David Janes
This homework assignment is part of ECE 305 "Semiconductor Device Fundamentals" (Purdue University). It contains 7 problems which lead students through a comparison of the depletion approximation and the exact analysis of a PN junction diode.
Exercises for FETToy
11 Oct 2005 | Teaching Materials | Contributor(s): Mark Lundstrom
This series of exercises uses the FETToy program to illustrate some of the key physical concepts for nanotransistors.
Ballistic Nanotransistors - Learning Module
07 Dec 2005 | Learning Modules | Contributor(s): Mark Lundstrom
This resource is an introduction to the theory ballistic nanotransistors. No transistor is fully ballistic, but analyzing nanotransistors by neglecting scattering processes provides new insights into the performance and limits of nanoscale MOSFETs. The materials presented below introduces the basic theory and shows how it can be applied to current problems in device research. The concepts are illustrated by exercises that make use of live simulations with the program, FETToy.
Notes on the Ballistic MOSFET
08 Oct 2005 | Papers | Contributor(s): Mark Lundstrom
When analyzing semiconductor devices, the traditional approach is to assume that carriers scatter
frequently from ionized impurities, phonons, surface roughness, etc. so that the average distance
between scattering events (the so-called mean-free-path, λ) is much shorter than the device.
When these conditions hold, we can describe carrier transport with drift-diffusion equations.
The traditional derivation of the MOSFET I-V characteristic above threshold assumes that the
drift current dominates . For the subthreshold current, we usually assume that diffusion
dominates . Numerical simulation programs include both drift and diffusion under all bias
conditions (e.g. MINIMOS ). As devices
shrink, however, we should consider the possibility that the device dimensions become
comparable to the mean-free-path for scattering. In the limit, L << λ, where the channel length is
much shorter than the mean-free-path, we can ignore scattering completely. In this case, the
operation of a MOSFET would be more like a vacuum tube than like a conventional
semiconductor device. In practice, scattering always occurs, but it is common now for the
critical, current-limiting part of the device to be comparable in size to a mean-free-path. Modern
devices, therefore, operate between the drift-diffusion and ballistic regimes. Drift-diffusion
theory continues to provide insights into the operation of small semiconductor devices, but a
ballistic treatment provides new insights that may prove useful as MOSFETs are scaled to their
limits and as new devices are explored. The modern device engineer should be familiar with
both approaches. In these notes, we develop a simple theory for the ballistic MOSFET.
An Electrical Engineering Perspective on Molecular Electronics
26 Oct 2005 | Online Presentations | Contributor(s): Mark Lundstrom
After forty years of advances in integrated circuit technology, microelectronics is undergoing a transformation to nanoelectronics. Modern day MOSFETs now have channel lengths that are less than 50 nm long, and billion transistor logic chips have arrived. Moore's Law continues, but the end of MOSFET scaling is in sight. At the same time, there are exciting new advances in molecular electronics and related fields. How long will the evolutionary approaches that have been so successful for 40 years continue to fuel progress?
Simple Theory of the Ballistic MOSFET
11 Oct 2005 | Online Presentations | Contributor(s): Mark Lundstrom
Silicon nanoelectronics has become silicon nanoelectronics, but we
still analyze, design, and think about MOSFETs in more or less in the
same way that we did 30 years ago. In this talk, I will describe a
simple analysis of the ballistic MOSFET. No MOSFET is truly ballistic,
but approaching this familiar device from a different perspective can
be useful. The talk will introduce a very simple, general model, then
apply it to the planar MOSFET. My objective is to describe the theory
in enough detail so that you can intelligently use the program,
FETToy, or write a more general program yourself.
Moore's Law Forever?
13 Jul 2005 | Online Presentations | Contributor(s): Mark Lundstrom
This talk covers the big technological changes in the 20th and 21st century that were correctly predicted by Gordon Moore in 1965. Moore's Law states that the number of transistors on a silicon chip doubles every technology generation. In 1960s terms that meant every 12 months and currently this means every 18-24 months. This talk explores the challenges of doubling transistors on chips and some new technologies examined by researchers.
Nanoelectronics: The New Frontier?
18 Apr 2005 | Online Presentations | Contributor(s): Mark Lundstrom
After forty years of advances in integrated circuit technology, microelectronics is undergoing a transformation to nanoelectronics. Modern day MOSFETs now have channel lengths of only 50 nm, and billion transistor logic chips have arrived. Moore’s Law continues, but the end of MOSFET scaling is in sight.
07 Jul 2004 | Online Presentations | Contributor(s): Mark Lundstrom
In non-specialist language, this talk introduces CMOS technology used for modern electronics. Beginning with an explanation of "CMOS," the speaker relates basic system considerations of transistor design and identifies future challenges for CMOS electronics. Anyone with an elementary understanding of transistors will benefit from this presentation.
04 Aug 2004 | Online Presentations | Contributor(s): Mark Lundstrom
The transistor is the basic element of electronic systems. The integrated circuits inside today's personal computers, cell phones, PDA's, etc., contain hundreds of millions of transistors on a chip of silicon about 2 cm on a side. Each technology generation, engineers shrink the size of transistors by a factor of two, which doubles the number of transistors on a chip. This "device scaling" lowers the cost of the electronic system and increases its performance. This talk focuses on how transistors function, and any listener with a basic understanding of physics will learn about transistors, device scaling, and future challenges in this field from this presentation.
06 Apr 2005 | Online Presentations | Contributor(s): Mark Lundstrom
This presentation is an overview of the Network for Computational Nanotechnology (NCN) presented at the first NCN Student Conference in April 2005. It is intended to give students an understanding of the NCN's vision and mission.
Nanotechnology 501 Lecture Series
22 Feb 2005 | Series | Contributor(s): Gerhard Klimeck (editor), Mark Lundstrom (editor), Joseph M. Cychosz (editor)
Welcome to Nanotechnology 501, a series of lectures designed to provide an introduction to nanotechnology. This series is similar to our popular lecture series Nanotechnology 101, but it is directed at the graduate students and professionals.
Electronic Transport in Semiconductors (Introductory Lecture)
25 Aug 2004 | Online Presentations | Contributor(s): Mark Lundstrom
Welcome to the ECE 656 Introductory lecture. The objective of the course is to develop a clear, physical understanding of charge carrier transport in bulk semiconductors and in small semiconductor devices.The emphasis is on transport physics and its consequences in a device context. The course does not focus on theory or computer simulation; it is a practical course for those interested in devices.
NSF NCN Overview
26 Jul 2004 | Online Presentations | Contributor(s): Mark Lundstrom
NSF NCN Overview
Nanoelectronics and the Future of Microelectronics
22 Aug 2002 | Online Presentations | Contributor(s): Mark Lundstrom
Progress in silicon technology continues to outpace the historic pace of Moore's Law, but the end of device scaling now seems to be only 10-15 years away. As a result, there is intense interest in new, molecular-scale devices that might complement a basic silicon platform by providing it with new capabilities - or that might even replace Silicon technology and allow device scaling to continue to the atomic scale. As the science of nanoelectronics continues to advance rapidly; it's time to begin thinking seriously about how to turn the promise of nanoscience into practical nanotechnologies.
Theory of Ballistic Nanotransistors
27 Nov 2002 | Papers | Contributor(s): Anisur Rahman, Jing Guo, Supriyo Datta, Mark Lundstrom
Numerical simulations are used to guide the development of a simple analytical theory for ballistic field-effect transistors. When two-dimensional electrostatic effects are small, (and when the insulator capacitance is much less than the semiconductor (quantum) capacitance), the model reduces to Natori's theory of the ballistic MOSFET. The model also treats twodimensional electrostatics and the quantum capacitance limit where the semiconductor quantum capacitance is much less than the insulator capacitance. This new model provides insights into the performance of MOSFETs near the scaling limit, and a unified framework for assessing and comparing a variety of novel transistors.