THE FORMATION OF CU3SI - MARKER EXPERIMENTS

Implanted rare gas markers, as well as a thin tungsten marker, show that the silicide Cu3Si, which is the first phase to form on the reaction of a copper film with a silicon substrate, grows by the motion of copper atoms. The same process seems to be at work in the formation of the silicide by ion mixing, but the one result obtained in that case is not unambiguous since the observed disappearance at the surface of the implanted marker might be due as well to interface drag effects as to the specificity of the mobile atoms. The low temperature of formation of the silicide, about 200°C, is discussed in terms of what is known about point defects and diffusion in the very similar compound Cu3Sn. © 1990.