Basic Principles
The history
Types of STM measurements
Problems and Solutions
P1: Draw an energy-position diagram for a metal surface interfacing the vacuum. Draw in the work function. How is dependent on Eo and EBarr?
P2: How big is the factor of change in the tunneling current if you scan over an atom on the surface? Use c2 ~1010/(ev)1/2m.
P3: If you can scan the same sample with 2 different tips, do you get identical tunneling images? How do you explain this? A condition for a suitable a tip material?
P4: For every operation mode think of some advantages or disdavantahge.
P5: Try to explain why the sample holder can follow the slower but not the faster movement. Remember that the accelerating force to the cylinder has to be gained from the adhesive friction. Try to elucidate this fact with a small object (e.g. pen) that you move along a piece of paper – like the sample holder on its supporting surface.
P6: Is it possible to reach a presision of displacement of one single atomic layer with the above mentioned conversion of the piezocrystals? How would you allocate the minimal and maximal voltage of the control electornics if you want to examine a square sample with a sidelength of 350 nm?
P7: The scanning force microscope is a development of the scanning tunneling microscope. Some advange and disadvantage of the scanning force microscope with respect to the scanning tunneling microscope.
P8:
QING SHI 
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