Nanoelectronics
Chapter 1 Introduction to
Nanoelectronics
Q.Li@Physics.WHU@2015.3
1
• COURSE DESCRIPTION
• This course focuses on the fundamental concepts and
principles of nanoelectronic materials and devices.
Nanoelectronics is concerned with electronic devices
with one or more dimensions at nanoscale. The lecture
will cover the electronic properties of solids including
semiconductors in samples of physical dimension of
~100 nm or less, and the corresponding basic device
building blocks such as quantum dot (QD), single
electron transistor (SET), nanowire, carbon nanotube
(CNT), graphene, etc. The course will consider the
design, simulation and analysis of a variety of
nanoscale devices ("quantum" or "mesoscopic"
devices) and examine the most notable, novel
applications.
Q.Li@Physics.WHU@2015.3
2
Course Outline
•
•
•
•
•
•
•
•
•
•
•
•
Course and Syllabus Overview
Classical particles, classical waves, and quantum particles
Quantum Mechanics of Electrons
Confined Electrons / Electrons Subject to a Periodic Potential
Tunnel Junctions and Applications of Tunneling
Coulomb Blockade and the Single-Electron Transistor
Carbon Nanotubes and Nanowire Transistors
Many Electron Phenomena-Particle Statistics
Models of Quantum Wells, Quantum Wires and Quantum Dots
Nanowires, Ballistic Transport, and Spin Transport
NanoCMOS / Silicon-on-Insulator (SOI) CMOS
Fundamental Limits to Scaling
Q.Li@Physics.WHU@2015.3
3
Depiction of a CNT FET
Q.Li@Physics.WHU@2015.3
4
Q.Li@Physics.WHU@2015.3
5
1.1 The “Top-Down” Approach
• Microelectronics Industry (from William
Shockley to Chenming Hu)
• Cost of manufacturing processes: a new
integrated circuit manufacturing plant costs
more than several billion US dollars
Q.Li@Physics.WHU@2015.3
6
The First Transistor (BJT)
(Bardeen, Shockley and Brattain @ 1948 in Brattain’s lab)
Q.Li@Physics.WHU@2015.3
7
Story behind the First BJT
Bardeen was a quantum physicist, Brattain a gifted
experimenter in materials science, and Shockley,
the leader of their team, was an expert in solidstate physics.
1947: W. Brattain and J. Bardeen (Bell Labs)
experimentally demonstrated the device
J. Pierce (Bell Labs) name the device: transfer +
resistor = transistor
1949: W. Shockley theoretically described bipolar
junction transistor
1956: Nobel Prize
Q.Li@Physics.WHU@2015.3
8
Story behind the First BJT
Walter H. Brattain was born on Feb.
10, 1902 in Xiamen, China, grew up
in Washington state. He had double
majors: physics and mathematics.
He and his three classmates: known
as “the four horsemen of physics”.
He worked in National Bureau of
Standards (later called NIST) from
1927 to 1929, then joined Bell Labs.
Q.Li@Physics.WHU@2015.3
9
Story behind the First BJT
John Bardeen was born in
Madison, Wisconsin on May 23,
1908. He had a major in
Electrical Engineering. He joined
Shockley’s group of solid state
physics. The group met almost
daily to discuss field effect and
surface states.
Bardeen was the only person to have won the Nobel
Prize in physics twice. (also, BCS theory in 1972)
Q.Li@Physics.WHU@2015.3
10
Story behind the First BJT
William B. Shockley was born in
London, England. His Ph.D. thesis was
Electronic Bands in Sodium Chloride
(NaCl).
Shockley tried to commercialize a new
transistor design from 1950s to
1960s, leading to California’s “silicon
valley” located in San Jose.
Shockley Semiconductor Laboratory built the basis of
modern electronics: transistors and circuits.
The “traitorous eight” are eight men who left Shockley
Semiconductor Laboratory in 1957.
Q.Li@Physics.WHU@2015.3
11
Story behind the First BJT
From left to right: Gordon Moore, C. Sheldon Roberts, Eugene
Kleiner, Robert Noyce, Victor Grinich, Julius Blank, Jean Hoerni
and Jay Last. (1960) They found
“Fairchild Semiconductor”.
Q.Li@Physics.WHU@2015.3
12
Fin field effect transistors
Prof. Chenming Hu
(FinFET, courtesy from Intel)
Q.Li@Physics.WHU@2015.3
13
1.1.1 Lithography
Q.Li@Physics.WHU@2015.3
14
1.1.1 Lithography
• Resolution of an optical lithography process
𝜆
𝑅 = 𝑘1
𝑁𝐴
K1 is a constant. λ is the wavelength of the source. NA is called
the numerical aperture (0.5-0.9).
• Immersion lithography
𝜆
𝑅 = 𝑘1
(𝑁𝐴)𝑛
• Extreme ultraviolet (EUV) and X-ray lithography
• Electron Beam Lithography (EBL)
• (in research) Negative index of refraction materials
Q.Li@Physics.WHU@2015.3
15
1.2 The “Bottom-Up” Approach
• Richard Feynman in a speech, “There’s Plenty
of Room at the Bottom.”
• SEM, STM, TEM and AFM push the resolution
limit to 0.1 nm.
• In contrast to “top-down” approach, emphasis
on atom-by-atom manipulation / movement
• Include chemical, biological self-assembly,
mechanical assembly of devices,
electrophoretic / dielectrophoretic assembly.
Q.Li@Physics.WHU@2015.3
16
1.3 Why Nanoelectronics
• Benefits of smaller transistors: faster and
higher integration density
• Device fabrication: it is difficult to extend
optical lithography into nanoelectronics
• Device operation: must include the law of
quantum physics
• Heat dissipation: the biggest problem
Q.Li@Physics.WHU@2015.3
17
1.4 Nanotechnology Potential
•
•
•
•
•
•
•
Nanoparticles
Nanomaterials
Nanoelectronics
Nano-optics
Nanomagnetics
Nanofluidics
Nanobioelectronics, including
chemical/bioweapons detection
Q.Li@Physics.WHU@2015.3
18
1.5 Main Points
•
•
•
•
•
•
Understand the various size units
History of microelectronics
The limit of optical lithography
What is called bottom-up approach
Problems in downscaling current electronics
General sense of nanotechnology-related
products
Q.Li@Physics.WHU@2015.3
19
1.6 Problems
• The definition of “Quantum Dot”?
• Briefly describe lithography techniques?
• How to prepare yourself as a scientist or
engineer?
Q.Li@Physics.WHU@2015.3
20