Abstract
The influences of implantation impurities, such as BF 2 , B, F, As and P, as well as silicon substrate crystallinity on the formation of NiSi 2 at 200-280°C in nickel thin films on ion-implanted silicon, have been investigated by transmission electron microscopy. In implantation-amorphous samples no NiSi 2 formation was detected at 200-280°C. The presence of BF 2 , B, and F atoms was found to promote the epitaxial growth of NiSi 2 in nickel thin films on crystalline silicon at low temperatures. Little or no effect on the formation of NiSi 2 was found for As + - and P + -implanted samples. The results indicated that the influences of the implantation impurities are not likely to be chemical in origin. The presence of electrically active impurities in crystalline silicon alone was not sufficient to induce the formation of epitaxial NiSi 2 at low temperatures. On the other hand, good correlation was found between the atomic size factor and resulting stress and NiSi 2 epitaxy at low temperatures.