Patent ID: 6376885
Filing Date: 2002-04-23
Classification: H01L

Abstract:
A method for forming a semiconductor device, the method comprising:providing a substrate, on which there is a field oxide (FOX) layer to define out an active region; forming a metal-oxide semiconductor (MOS) device on the substrate at the active region, wherein the MOS transistor includes a gate structure with a spacer on its sidewall, and a source/drain region in the substrate at each side of the gate structure, the gate structure has a gate oxide layer on the substrate, a gate layer on the gate oxide layer, and a cap layer on the gate layer, wherein the cap layer and the FOX layer have about the same height; removing the cap layer to form a trench space on the gate layer between the spacer; forming a blanket silicon layer over the substrate; forming a refractory metal layer on the silicon layer; performing a first thermal treatment to trigger a reaction between the silicon layer and the refractory metal layer, whereby a silicide layer is formed thereon; and polishing the silicide layer, using the FOX layer as a polishing stop, so that a remaining portion of the silicide layer includes a first silicide layer on the gate layer filling the trench space, and a second silicide layer on the source/drain region filling a space between the spacer and the FOX layer.