Transcript Tutorial 1 (PowerPoint)

Tutorial 1
Derek Wright
Wednesday, January 5th, 2005
This Course
• The Good:
– This course could be called: The “How
Everything That’s Cool Works” Course
– Mostly qualitative
• If you get how everything works, you’ll do great
• If you like to memorize how to do a certain type of
problem, you might not do as well
– Hopefully some good demos
– Great way to decide if grad school is right for
you
This Course
• The Bad:
– Relies on some stuff you haven’t been taught
yet (process technology)
– Have to get used to the idea that things don’t
work the same at the nanometer scale
– Textbook is good, but way too expensive
Textbook
• Not recommended
• $156
• Technology is
changing so fast,
most of this book
will be obsolete in a
few years
• However, it’s a really
cool book!
What is Nanotechnology?
• Any technology that has at least one
dimension at the nanometer scale
– Quantum Wells
– Giant Magnetoresistance
– Carbon Nanotubes
– Things that use tunneling
– Atomic Force Microscopes
Why Use Nanotechnology?
• There are two main reasons:
– The small feature size allows miniaturization
and high information/work density
– The small feature size allows the exploitation
of quantum effects
Examples of Information Density
• Hard Drives now
exploit Giant
Magnetoresistance
(GMR) to greatly
increase density
Examples of Information Density
• Display quality is
increasing due to
feature size reduction
• Organic Light Emitting
Diodes are a
promising candidate
for new displays
Examples of Information Density
• Shrinking feature size
means smaller, faster
chips
Examples of Quantum Devices
• Quantum computers exploit quantum spin states
of molecules to enable bit-level parallelism
Examples of Quantum Devices
• Quantum Wells can selectively trap electrons
with quantized energy levels
Examples of Quantum Devices
• Tunnel Diodes make
use of an electron
being a probability
wave (Heisenberg’s
Uncertainty Principle)
and a highly skewed
band diagram.
• Negative Resistance
Examples of Quantum Devices
• “How many electrons does it take to
remember the entire contents of the
Library of Congress? Only one, according
to University of Michigan professor Philip
Bucksbaum. Since electrons, like all
elementary particles, are actually waves,
Bucksbaum has found a way to phaseencode any number of ones and zeros
along a single electron's continuously
oscillating waveform.” – EE Times
Building Devices
Exposure/
Developing
Deposition/
Growth or
Etching
Photoresist
Application
Photoresist
Etching
Deposition vs. Growth
• Deposition:
– New material is stuck on top of the substrate
(e.g. Amorphous Silicon)
• Growth:
– A form of deposition where new material
reacts with the substrate to form a compound
(O2 reacts with Si substrate to form SiO2
insulator)
Deposition vs. Growth
Inert material
Deposited Material
Wafer
Reactive material
Grown Material
Wafer
Some Deposition Techniques
• Sputter
• Molecular Beam Epitaxy
• Chemical Vapour Deposition
– Thermal CVD
– Plasma Enhanced CVD
– Low Pressure CVD
• Spin-on
• Printing
Some Growth Techniques
• Uses CVD to cause reactive species to hit
the surface
• PECVD is great because it strips electrons
off gas-phase molecules and causes many
reactive ions to form
Etching Techniques
•
•
•
•
Wet Chemical Etching
Ion Beam Etching
Reactive Ion Etching
Focused Ion Beam Etching
Example of RIE in DRAMs
• RIE allows very high
aspect ratio trenches
to be created
• Extremely useful for
shrinking capacitor
size in DRAMs
Course Outline
• Process Technology:
– Deposition
– Growth
– Lithogrpahy
– Etching
– Micromachining
– Ashing
– Chemo-Mechanical Polishing
Course Outline
• Scanning Probe Techniques:
– Scanning Tunnelling Microscopy
– Scanning Force Microscopy
– Imaging of Soft Materials
– Manipulating Atoms and Molecules
– Chemical Reactions with STM
Course Outline
• Sensor Arrays and Imaging Systems:
– Physical Principles of Sensors
– Optical Imaging Systems
– IR Imaging Systems
– Electronic Nose
– Tactile Sensors and Arrays
Course Outline
• Displays:
– Liquid Crystal Displays
– Organic Light Emitting Diode Displays
– Field Emission and Plasma Displays
– Electronic Paper
Course Outline
• Logic Devices:
– Silicon MOSFETs
– Ferroelectric Field Effect Transistors
– Resonant Tunneling Quantum Devices
– Single-Electron Devices
– Carbon Nanotubes
Course Outline
• Mass Storage Devices:
– Storage Principles
– Hard Disk Drives
– Magneto-Optical Discs
– Compact and Digital Versatile Discs
– AFM-Based Mass Storage
Course Outline
• Nano-BioSystems:
– Neuro-Electronic Interfacing
– Biomaterials
– DNA Microarrays
Useful Websites
• Google (duh)
• ieeexplore.ieee.org
• www.eetimes.com
Thank You!
• This presentation will be available on the
web.