1. Final Project
Robbie Lee
Scanning Tunneling Microsopy

2. What is STM?
3. STM is a microscope that can image at the atomic level.STM uses an atomically sharp tip to scan the surface of a sample. It scans across the sample using a constant current between the tip and the surface to map out the topography of the sample at an atomic level.STM is being used to develop nanotechnology.
4. How Does It Work?
5. What Kind of Tip Do I Use?
6. What Kind of Sample Do I Use?
7. What I Have Done(1)
8. What I Have Done(2)-Dibenzo[a,l]pentacene
9. Structure of Dibenzo[a,l]pentancene
10. Why Failure?
Too Much Current; I used 1nA of current which was too much for the Dibenzo[a,l]pentacene. Too much current made bumps on the surface, which I thought of molecules
Silence; noisy sound occurs vibration
Vacuum; less interference of air and sound
Cool temperature; it helps surface settle down
11. How Can We Do To Change That?
Use similar conditions to scan Dibenzo[a,l]pentacene
Less Vibration
Less Noisome
Cool Temperature
12. What I Have Learned
Large Tunneling Current vs. Small Tunneling Current
What To Do If The Scope Does Not Work Properly/Not Approacing
Vapor Deposit
Annealing
13. Reflections on Experiencing in Research Class