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NANO Week
District 205
What is Nanotechnology?
Understanding and using objects that are less than 100 nm in size
Nanotechnology can be used in (let’s talk about applications and implications)
Medicine Electronics Environment Anything!
Our Goals…
To increase your awareness about the field of nanotechnology.
To share with you our excitement about research.
To encourage you to consider careers in science and engineering.
Let’s get on the same page!
How many nanometers can fit inside one meter?
Name the smallest thing you can see with your eyes?
What is the thickness of one strand of hair?
What is the size of the wavelength of light?
We will talk about the questions and give the answers after the movie clip!
The size of objects and the EM spectrum
\“Arrange the objects from largest to smallest, left to right.”
Eiffel Tower Atomic NucleiHumanMoleculesPinpointProtozoansHoney BeeAtoms
Understanding size - Where do they fit on the wavelength scale?
Object and Source Matching
Eiffel Tower Atomic NucleiHumanMoleculesPinpointProtozoansHoney BeeAtoms
Why should you care about
nanoscience in our world?
target
source
detector
…sometimes you’ll need a lens
How do we see an object?Can we see nano objects?
Requirements of Vision
The light that reaches the eye must have a color(wavelength) between red (760nm) and blue (400nm) – or a mixture of these colors.
The light that reaches the eye must be sufficiently bright – usually requires a sufficiently bright source
wavelength in nm
400 760 3000760290 320
Seeing Atomic Structure
Light must be about 0.1nm in wavelength to see atomic structure: x-rays
Our eyes can’t detect x-rays - 0.1nm light - (5000 times smaller wavelength than we can see)
Options• Use x-rays and detector (to replace the eye)• Use particles (e.g. electrons) and detector
Electrons of the appropriate wavelength are easier to produce and better focusing compared to light
• Scanning Electron Microscope (SEM)
Imaging techniques• Atomic Force Microscope (AFM)• Scanning Tunneling Microscope (STM)
Our Suite of Instruments to “see” surfaces
SEM Scanning Electron Microscope
AFM Atomic Force Microscope
STM Scanning Tunneling Microscope
Scanning Electron Microscope (SEM)
(1)Focus a beam of electrons on the surface,
(2)Collect the backscattered electrons from the surface of the sample,
(3) Observe a visual map of a computer
generated image
Atomic Force Microscope (AFM)
(1)Focus a beam of light on the back of a lever,
(2)Collect the height deflections based on force interactions between the tip and the sample surface,
(3) Observe a visual map of a computer
generated image
Scanning Electron Microscope (STM)
(1)Apply a voltage to the tip of a wire,
(2)Observe and measure the tunneling current between the tip and the sample surface,
(3) Observe a visual map of a computer generated
image
Thank you!
