Granted Patent B2

US 7,358,574 · App. 11/320,303 · Granted Apr 15, 2008

Abstract

Claims (18)

1. A semiconductor device comprising:

a silicon substrate having a field oxide layer formed therein to define an active region;

source/drain regions formed in the active region of the substrate;

a gate oxide layer and a gate electrode formed on the substrate between the source/drain regions;

dielectric spacers formed on sidewalls of the gate electrode;

a silicide layer formed on both the gate electrode and the source/drain regions; and

a silicide-blocking layer formed over the borders between the field oxide layer and the source/drain regions, covering edges of the source/drain regions, and obstructing the extension of the silicide layer.

2. The device of claim 1 , wherein the edges of the source/drain regions are higher than edges of the field oxide layer, and the silicide-blocking layer covers the higher edges of the source/drain regions.

3. A method of fabricating a semiconductor device, the method comprising:

forming a field oxide layer in a silicon substrate to define an active region;

forming a gate oxide layer and an overlying gate electrode on the active region of the substrate;

forming dielectric spacers on sidewalls of the gate electrode;

forming source/drain regions in the active region of the substrate;

forming a silicide-blocking layer over the borders between the field oxide layer and the source/drain regions; and

forming a silicide layer on both the gate electrode and the source/drain regions except the blocking layer.

4. The method of claim 3 , wherein the forming of the silicide-blocking layer includes depositing an insulating layer over the substrate and selectively etching the insulating layer.

5. The method of claim 3 , wherein the silicide-blocking layer is formed of silicon oxide or silicon nitride.

6. The method of claim 3 , wherein the silicide-blocking layer is formed of the same material as the dielectric spacers.

Assignments (8)