Other Sources
Surface Contamination
Substantial contamination at the surface of a sample such as a fingerprint or oil film can cause AFM image artifacts. Such artifacts appear as streaks on the image especially in locations where there are “sharp” features and edges on the sample’s surface. Often the streaking can be reduced or even eliminated by cleaning the sample with a high purity solvent.   Figures 26A-B: (A) SEM image of a test pattern that is contaminated. (B) AFM image of the same test pattern that is covered with contamination. The contamination is identified by the streak marks at the top of the scan. Electronics
Image artifacts can appear in AFM scans because of faulty electronics. Artifacts from electronics most often appear as oscillations or unexplainable repeating patterns in an image. Electronic ground loops and broken components are usually the source of electronic noise.  Figure 27: Image of a test pattern that has electronic noise at the top and bottom of the scan. The electronic noise in this case was a result of not having a ground wire attached to the stage. The artifact is identified by the oscillations. Vacuum Leaks
Atomic force microscopes that are designed for imaging wafers and discs often use a vacuum chuck to hold the wafer/disc while scanning images. A leak in the vacuum between the specimen holder and the specimen can cause image artifacts. The artifact causes a loss of resolution in the image. Cleaning the vacuum chuck and sample often eliminates this problem.
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