BORON OUTDIFFUSION FROM POLYCRYSTALLINE AND MONOCRYSTALLINE COSI2

The aim of this work was to investigate the outdiffusion of implanted boron from polycrystalline CoSi2 overlayers into silicon. A special effort was made to assess the influence of interface roughness on the quantification of the dopant profiles. A comparison with outdiffusion from epitaxial CoSi2 made by ion beam synthesis was undertaken which showed that the second one suffered much less from interface roughness. A comparison of the outdiffused profiles with doping from other sources such as poly-silicon showed that boron outdiffuses in a very similar way from both types of overlayers. Further, technological variations, such as the type of capping layer, used to prevent dopant evaporation from the surface of the silicide, were studied.