We are investigating a new technique of injecting faults into VLSI chips using an Atomic Force Microscope (AFM). The project is funded by the National Science Foundation and is under the direction of Dr. Jien-Chung Lo. The AFM is capable of manipulating and scanning particles at the atomic level. The purpose of this aspect of the project is to develop a technique to cut a certain amount of a wire with surgical precision.

1. The sample is moved under the tip on the end of the cantilever in a raster-like pattern.
2. A laser is constantly defelecting off the cantilever into the photodiodes to detect z direction changes.
3. As the sample encounters a z-direction surface feature, the Van der Waals forces force the cantilever to deflect upwards.
4. The laser now deflects to a different part of the photo-diode which is detected bythe software.
5. The neccesary adjustments are made to the scanner (ie. it is compensated in the z-direction). 

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