An auger analysis of substrate-layer interactions in the chemical vapor deposition and activated reactive evaporation of TiC

Abstract

A formalism for quantitative Auger analysis is developed to account for “matrix effects” and peak shape changes in WCTiCTa(Nb)CCo materials by including shape factors and a linear term in the inverse sensitivity factors of carbide single crystals and binary carbide alloys. Atomic concentration profiles are then obtained for carbon, titanium, W+Ta(Nb) and cobalt across the interface between WCTiC Ta(Nb)CCo substrates and TiC coatings deposited by chemical vapor deposition (CVD) and activated reactive evaporation (ARE). Phase compositions of the near- surface region of the substrate estimated from the atomic concentrations indicate that the concentration of carbon dissolved in the binder phase drops from approximately 28 at.% prior to deposition to approximately 10 at.% after the deposition by both processes of TiC coatings about 5 μm thick. The amount of binder phase near the CVD substrate surface was found to be approximately twice as great as that near the ARE substrate surface, probably because of significant transport of cobalt at the higher temperatures used for CVD.