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Small Sample Mounting Technique for Scanning Electron Microscopy and X-Ray Analysis

NCJ Number
218832
Journal
Forensic Science Communications Volume: 1 Issue: 2 Dated: July 1999 Pages: 1-2
Author(s)
Dennis C. Ward
Date Published
July 1999
Length
2 pages
Annotation
This paper describes a mounting method for analyzing small samples for scanning electron microscopy (SEM) and X-ray analysis.
Abstract
The mounting method described has several advantages over commonly used double-sided specimen mounting tapes and liquid adhesives. It uses pyrolytic carbon planchets (available from electron microscopy suppliers) as specimen mounts. These disks are nonporous, glass-like, flat, and reusable. The described mounting method has a number of advantages over conventional mounting methods. The elemental contribution of the substrate is only carbon, and the adhesive layer is stable under conditions of high-beam current and high vacuum. Also, the adhesive layer is very thin, such that a particle can easily be removed from the mount after analysis; charging of an uncoated sample during observation is minimized. The background is structurally featureless, which provides optimal photographic presentation of the sample, and the noninvasive, nondestructive characteristic of the adhesive permits additional analytical procedures to be performed. The mounting method is not recommended for handling populations of very small particles such as gunshot primer residue. 2 references