Method of forming self-aligned silicide in semiconductor device

Abstract

There is provided a semiconductor device fabrication method. In the method, a gate layer is formed on a semiconductor substrate and patterned to form a first resultant structure, a metal layer is formed on the first resultant structure, a capping layer is formed on the metal layer, a metal silicide is formed on the gate layer by heating the substrate at a first temperature, unreacted metal layer and first capping layer are removed to form a second resultant structure, a second capping layer is formed on the second resultant structure, and the substrate is heated at a second temperature higher than the first temperature. The second capping layer suppresses a silicidation rate in the secondary heat treatment, thereby allowing a silicide of a good morphology to be achieved.