When analyzing samples for analytical work in the SEM or for surface analysis the stubs used are nearly all made from aluminum and sometimes brass. This can present a problem for the electron microscopist when doing x-ray analysis. Vitreous carbon discs are ideal substrates for backscattered electron imaging and x-ray analysis. Our vitreous carbon discs are highly conductive and are free of any characteristic x-rays with the exception of carbon.
Carbon (graphite) or vitreous carbon discs to prevent interference.
To prevent interference of the stub surface you can place a carbon (graphite) disc or a vitreous carbon disc between the stub and the specimen and mount the specimen directly on these discs. Both discs varieties (also called planchets) form a protective shield.
Differences between vitreous carbon discs and carbon (graphite) discs.
Vitreous carbon is superior in hardness, surface finish, mechanical and chemical stability but it is more expensive than carbon discs. The table below will give guidance to which material is best for the application at hand. Generally speaking, vitreous carbon is the better choice, but for less demanding applications carbon (graphite) discs will do just fine.
V= Best O= Medium X= Not Recommended