Atom movements occurring at solid metal-semiconductor interfaces

Solid metal-semiconductor interfaces often undergo chemical reaction at rather low temperatures, in some cases not much above room temperature. After some general discussion of these reactions, more detailed consideration is given to simple noncompound-forming systems, and, in particular, to the Si-Al, Ge-Al, and Si-Au systems. Diffusive transport of Si or Ge in these solid metallizations is very rapid, though the converse process, diffusion of metal in solid Si or Ge, is usually so slow as to be negligible. The interface reaction itself is less well understood but is becoming controllable in intrinsically favorable cases like Ge-Al and in other cases by more sophisticated means.