METHOD FOR FORMING SELF-ALIGNED SILICIDE LAYER USING AMMONIA PLASMA TO IMPROVE RELIABILITY OF PROCESS FOR FORMING SELF-ALIGNED METAL SILICIDE LAYER

摘要

PURPOSE: A method for forming a self-aligned silicide layer using ammonia plasma is provided to improve reliability of a process for forming a self-aligned metal silicide layer by eliminating a metal compound layer formed on an insulation layer pattern by a plasma treatment process. CONSTITUTION: A metal layer is formed on a semiconductor substrate(21) to which a conductive layer made of silicon and a spacer(27) are exposed. The metal layer and the conductive layer are annealed to selectively form a metal silicide layer on the conductive layer. The resultant structure having the metal silicide layer is dipped into a strong acid to eliminate an unreacted metal layer remaining on the surface of the insulation layer pattern. A plasma treatment process using ammonia gas is performed on the resultant structure to transform the metal compound layer remaining on the spacer into a metal nitride layer. The resultant structure is dipped into a strong acid again to remove the metal nitride layer.