Charging Effect on Soil Particles in Scanning Electron Microscopy (SEM)

Abstract

Scanning Electron Microscope (SEM), a tool for material characterization reveals information about surface and subsurface, composition, and defects in bulk materials. The objective of the article is to understand the parameters of soil particles on charging effect in scanning electron microscopy (SEM). The SEM images were obtained on colluvium soil particles by varying particle size (A=2-1mm, B=0.6-0.425mm, C=0.3-0.212mm, and D= <0.075mm), and number of conductive coatings (uncoated, single, and double). The article proposes a method for the preparation of soil particles for SEM imaging and is applicable for all types of soil particles. The study revealed that the soil particles of size greater than 212μm require double conductive coating and less than 75μm requires single coating to avoid charging effect. The sharpness of the image is questionable of soil particles greater than 212μm at 10000× magnification and above after double conductive coatings.