FREQUENTLY ASKED QUESTIONS ABOUT ATOMIC FORCE MICROSCOPY (AFM FAQ)

AFM Artifacts

by Peter Eaton

The page linked below describe some common artifats that occur in Atomic Force Microscopy(AFM), some of these might also occur in STM and other types of Scanning Probe Microscopy.
Many different artifacts that can appear in AFM images, on these pages, I will give examples to help you spot them and describe, where possible, how to avoid the artefact.


1. Tip Effects - The various artifacts that can occur due to the interaction of the tip with the sample.
General tip -sample convolution
Dirty / contaminated tips - caused by material stuck to the AFM tip, introduces strange shapes in to your image,
Blunt tips - blunt tips reduce image quality
Double/multiple tips - double tips can lead to images with "twinned" features.

2. Scanner Artifacts - Effects due to the peculiarities of the piezoelectric scanner
Piezo Creep - the way the piezo works can lead to distortions in the image.
Edge Overshoot - another piezo artifact, leading to increased step heights.

3. Other Artifacts
Sample Drift - sample movement distorts the image.
Laser interference patterns - laser interference leads to stripes in your image.
Flying Tip - when feedback is not adequate.

AFM FAQs


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This document was written by, and is maintained by Peter Eaton (peter.eaton@fc.up.pt)
Reproduction or distribution not allowed without my permission.
Please feel free to email me comments / questions / answers.
Document updated on 12th October 2007.