Auger electron spectroscopy studies of boron carbide

Abstract

Auger electron spectroscopy has been used to probe the electronic structure of ion bombardment (IB) cleaned surfaces of B9C and B4C samples. The shapes of the B‐KVV and C‐KVV Auger lines were found to be relatively insensitive to the bulk stoichiometry of the samples. This indicates that the local chemical environments surrounding B and C atoms, respectively, on the surfaces of the IB cleaned samples do not change appreciably in going from B9C to B4C. Fracturing the sample in situ is a way of producing a clean representative internal surface to compare with the IB surfaces. Microbeam techniques have been used to study a fracture surface of the B9C material with greater spatial resolution than in our studies of IB surfaces. The B9C fracture surface was not homogeneous and contained both C‐rich and B‐rich regions. The C‐KVV line for the C‐rich regions was graphitic in shape. Much of the C‐rich regions was found by IB to be less than 100 nm in thickness. The C‐KVV line from the B‐rich regions was carbidic and did not differ appreciably in shape from those recorded for the IB cleaned surfaces.