1. Notre Dame extended Research Community NANOWeek: The Power of Microscopes Optics Visible light Optical microscopes and telescopes Scanning electron microscope

2. The Metric Scale is relevant to LIFE  1m = 2 nd grade child  2.1m = Shaquille O’Neill  1/100m = 1 cm =~ width of pinky finger  1/1000m = 1 mm =~width of a dime  1/1,000,000 = 1 um (micron)  1/1,000,000,000 = 1nm 2 50-100 um thick 30-50 nm wide

3. The Nanometer Scale:  One inch equals 25.4 million nanometers.  A sheet of paper is about 100,000 nanometers thick.  A human hair measures roughly 50,000 to 100,000 nanometers in diameter.  Your fingernails grow one nanometer every second. 3

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5. A prism can separate white light into all the colors of the rainbow Image taken from www.opticalres.com

6. 6 How do we see? target source detector …and often you’ll need a lens

7. Magnifying Glass Magnification: 2-10x (Loupes 30x) One lens (Many Lenses and Prisms) Usually a biconvex lens - both sides are convex

8. Focal Length Magnified Right Side Up Shrunk Upside Side Up Focal Length

9. Activity: Assemble the Telescope! Arrrrgh!

10. Microscope Light Source Stage and Sample Objective Lens Ocular Lens (Eyepiece)

11. Magnification Objective Lenses 4x Magnification 10x Magnification 40x Magnification 100x Magnification 10x Magnification Total Magnification: 40x, 100x, 400x, 1000x Other techniques: Feature Size

12. Digital Microscope

13. 13 Example Image

14. 14 Scale

15. 15 What Comes Next?  How do we view things smaller than the wavelength of light?  What do we actually “see” when we use such techniques? http://www.mrs.org/s_mrs/doc.asp?CID=1803&DID=171434

16. 16 Basic SEM Idea e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- e-e- Some are absorbed Some are “reflected” Some is absorbed Some light is “reflected”

17. 17 Water Hose and Splash

18. 18 The “Splash” http://www4.nau.edu/microanalysis/Microprobe-SEM/Signals.html Primary electrons come from the beam Some electrons scatter back (BSE), and they move very fast Other secondary electrons (SE) are dislodged and move more slowly

19. 19 The Electron Beam Column http://bioweb.usu.edu/emlab/TEM-SEM%20Teaching/How%20SEM%20works.html Beam created from heated filament Beam travels through a vacuum Electro-magnetic fields act as lenses Scattered and “secondary” electrons are detected Electron beam hits the sample in a precise location Beam scans back and forth

20. Scanning Electron Microscope (SEM)