Unframed contacts using refractory metals

Unframed contacts are extremely useful for high density integrated circuits because they decrease the metal interconnection line pitch in contrast to framed vias where the metal frames around the vias or contact openings require a minimum design rule spacing between the frame edges and adjacent lines. A method is described for making unframed or nonoverlapping metal contacts to silicon junction regions using selective CVD tungsten films for contacts and molybdenum for interconnections.