Constant Force (Contact) Mode

In contact AFM, the tip is in perpetual contact with the sample.  The tip is attached to the end of a cantilever with a low spring constant, lower than the effective spring constant holding the atoms of most solid samples together.  As the scanner gently traces the tip across the sample (or the sample under the tip), the contact force causes the cantilever to bend and the Z-feedback loop works to maintain a constant cantilever deflection.
Contact Mode


Room 1043, Haworth Hall

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