Method of making a self-aligned silicide contact using polysilicon electrode as an etch mask

摘要

In fabricating the contact, the electrode layer of polycrystalline silicon whose rim portion is bonded via a layer portion of insulating material to the substrate, is used at least throughout the length of a part of its rim portion for the lateral delimitation of a etching process, as an etch mask, in the course of which a frame-shaped layer portion is formed underneath the rim portion of the electrode layer, and the contact area of the substrate as bordering on the layer portion is exposed. Following the deposition of a metal layer of a metal forming a silicide in a thickness smaller than the thickness of the layer portion, and the heating for forming the silicide, the metal which has so far not reacted with the silicon, is removed by using an etching agent selectively dissolving the metal.