Give+a+brief+description+about+preparing+samples

Since the SEM uses electrons to produce an image, most conventional SEM's require that the samples be electrically conductive!!! Specially designed SEM's called [|environmental SEM's] are now available which can be used to view non-conductive or even wet samples. “The regular SEM, which we have in the Iowa State Materials Science Department, requires a conductive sample. All metals are conductive and require no preparation to be viewed using an SEM. In order to view non-conductive samples such as ceramics or plastics, we must cover the sample with a thin layer of a conductive material.” http://mse.iastate.edu/microscopy/prep2.html