The pages below describe some common artifacts that occur in AFM, some of these might also occur in STM and other types of scanning probe microscopy. There are many different artifacts that can appear in AFM images. On these pages, I give some examples of what they look like to help you spot them and describe, where possible, how to avoid the artifact.

Note: This article is a short extract of some material from chapter 6 in my forthcoming book "Atomic Force Microscopy"


1. Tip Effects - The various artifacts that can occur due to the interaction of the tip with the sample.
General tip -sample convolution - convolution between the probe and the sample can change dimensions of features..
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.

 

Many more artifacts are discussed in chapter 6 of Atomic Force Microscopy.There is also a short quiz based on the material in that chapter.

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This article is copyright (2009) Peter Eaton