• Scanning probe: As the probe is moved over the gold sample, current flows between the probe tip and the sample. The processor holds the tip at a constant distance from the sample by keeping the electric current constant. Thus, changes in the vertical position of the probe will follow the contours of the sample’s surface. *Inset photo: Scanning Device: This device raises and lowers the probe. *Inset photo: Probe Tip: The tip of the probe is only one or two atoms in width. *Inset photo: Electron Flow -Electrons flow across a gap of about one nanometer (0.000001 mm) between the probe tip and the sample, producing an electric current.
• Processor: The processor sends, receives, and records information about the movement of the probe.
• Computer: A computer assembles a map of the sample’s surface, using data received from the processor. Color was added to the image shown on the computer screen.