Nanotechnology

Presented by Mr. Lundberg

Test your knowledge of scale... What is the thickness of a dollar bill.. in nanometers? (the answer will be revealed on a later slide)

Nanotechnology An introduction to a new world of great things that come in small packages …. a billionth of a meter! Quantum Dot (5 nm) (Semiconductor Nanocrystals) 1 nanometer is to an inch what 1 inch is to 400 miles.

Powers of Ten: Life on the Logarithmic Scale 1900: Cardboard Punch Cards 1935: Computing Machines (electromagnetic relays) 1940: Radio Vacuum Tubes 1947: Transistors 1972: Intel Integrated Circuit (Microprocessors)

Richard Feynman 1960 “When we get to the very, very small world – say circuits of seven atoms– we have a lot of new things that would happen that represent completely new opportunities for design. Atoms on a small scale behave like nothing on a large scale, for they satisfy the laws of quantum mechanics.”

What does this mean? When particles go nano they get a bit crazy! When particles are studied at the nano scale everything we understand about particles at the macroscale gets thrown out the window. Nano particles have new or exotic properties.

Some Nano Info. From the Greek word “nano,” meaning “dwarf.” (Nanometer is abbreviated as “nm”) Richard Feynman (1960) “There’s Plenty of Room at the Bottom” Term coined in 1974 by Nario Taniguchi (to describe machining tolerances < 1 um). The First Transistor (1947) A dollar bill is 100,000 nanometers thick.

Some “Nano-Ground Rules” 1.Structures where at least 1 item (usually 2 to 3) is 1 – 100 nm in size. 2.Substances behave differently at the nanoscale! 3.Nanotechnology builds on the ability to control or manipulate at the atomic scale.

How small are we talking about?

Another Look: How small are Nanostructures? Single Hair Width = 0.1 mm = 100 micrometers = 100,000 nanometers ! 1 nanometer = one billionth (10 -9 ) meter

and looking smaller still… Hair. Red blood cell 6,000 nanometers DNA 3 nanometers

All that glitters just might be gold! Gold???

Behaving Differently “Nanoprisms” – note the different colors vs. sizes

Size-Dependent Properties Bulk properties (1 gram – 1 lb.) Atomic properties What happens to properties? Electrical (resist and conduct) Thermal (conduct, insulate) Optical (color, reflectance) Mechanical (strength, elasticity) Today’s transistor

Another example of materials behaving “differently” Calcium carbonate in bulk— you get common chalk … put calcium carbonate in a stacked arrangement – you get the shiny shell of an abalone!

Nanotechnology Implications One of the top ten future technologies (Businessweek) Interdisciplinary topic involving physics, chemistry, math, biology and engineering… Potential impact in electronics, medicine, materials, and a wide variety of application areas. Too Small to See Nanotech Exhibit (opened at Disney Epcot Center on November 18, 2006)

Areas of Nanotechnology Biological Advanced materials Computer Applications C-60 “Buckyball” – 1nm (Buckminsterfullerene) R. Smalley, 1985 A nm is 1/10 the thickness of the tinted coating on sunglasses.

A Biological Example Gene Chips (DNA = 3 nm) “Spots” of DNA Sequences on a chip (500,000 locations) Used to measure gene expression

A Materials Example Carbon Nanotubes 2 nm –have 100 x tensile strength of steel Conduct electricity better than copper Are excellent conductors of heat Can be either conductors or semiconductors, depending on the arrangement of atoms. EM Photo of Carbon Nanotubes

An Optical Example: Micromirrors! Optical Semiconductors DLP “Micromirrors”

A Last Example: Ferrofluids! Fluids with magnetic particles at nanoscale (NASA, 1960 – to confine liquids in space)

So how do we get down to size? How do we see nanostructures? How do we make nanostructures? A human hair is about 100,000 nanometers wide.

How do we see nanostructures? AFM: Atomic Force Microscope! STM: Scanning Tunneling Microscope! 1950’s Era Electron Microscope

The AFM and STM: ( can measure differences as small as 1/10 of a nm) AFM STM

The AFM Microscope (think back to your record player!) Surface Vibrating Cantilever

The AFM The AFM uses a Laser light beam – not a stream of electrons. Images are seen by how the detector picks up the movement of the cantilever. AFM Animation

AFM Image of a Music CD You can see digital data on a music CD – (~ nm) the raised areas are “1’s” and the depressions are “0’s”

Nano Activity Measuring the Spacing Between Concentric Loops on CD’s, DVD’s, and Blue Ray DVD’s with LASERS!

A Nano-Summation: Small (very!) Different “New” Properties Future applications in all areas of life How well do we (and our students) understand this new technology?

Now that we see, how do we make nanostructures? Pattern them (Lithography) Use self-assembly Pick them up and move ‘em

Making a Microscopic Mask Silicon crystal Polymer film Electron Beam Lithography (“Top-down”)

Computer Chips are Made with Lithography IBM Copper Wiring On a Computer Chip Now – Nano chips! (each pore is 14 nm)

Self-assembly (“Bottom-up”) How do molecules arrange themselves in patterns? (snowflakes, soap bubbles..) The old “lock and key” mechanisms of enzymes in biological systems

Pick Them up and Move Them Use of AFM – Atomic force microscope And a “Nano- manipulator”

Pushing Nickel Atoms Around

Measuring and Moving