CMOS device structure with reduced risk of salicide bridging and reduced resistance via use of a ultra shallow, junction extension, ion implantation
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsChaochieh Tsai, Shun-Liang Hsu
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Abstract
A method for forming a CMOS device, with improved yield, performance and reliability characteristics, has been developed. Yield improvements have been addressed by the use of a dual insulator spacer, used to reduce the risk of salicide bridging, as well as the use of pocket implantation regions, used to reduce punchthrough leakage. An ultra shallow junction extension region has been created in a peripheral channel region, reducing the resistance of this region, thus enhancing the performance of the CMOS device. In addition, ultra lightly doped source and drain regions are used to relax reliability concerns, regarding hot electron injection.
Claims7
A complimentary metal oxide semiconductor,(CMOS) device structure, on a semiconductor substrate, comprising:
- field oxide regions in said semiconductor substrate;
- a device region between said field oxide regions;
- a polysilicon gate structure on said semiconductor substrate, in the center of said device region, with metal silicide on the top surface of said polysilicon gate structure;
- an insulator spacer, between about 100 to 400 Angstroms in thickness, comprised of a vertical spacer component, located on the sides of said polysilicon gate structure, and a horizontal spacer component, located on the top surface of said semiconductor substrate, extending between about 1000 to 3000 Angstroms, in length, from the side of said polysilicon gate structure;
- a heavily doped source and drain region, located in the surface of said semiconductor substrate, between a field oxide region and said polysilicon gate structure, and underlying said overlying horizontal spacer component, at a point where said horizontal spacer component is between about 500 to 1500 Angstroms from the edge of said polysilicon gate structure;
- a metal silicide layer on the region of said heavily source and drain region not covered by said horizontal spacer component;
- a space in said semiconductor substrate, between region of said heavily doped source and drain region, located under said horizontal spacer component, and the edge of said polysilicon gate structure, used for a peripheral channel region;
- a pocket ion implanted region, opposite in conductivity type to said heavily doped source and drain region, in said peripheral channel region, to a depth between the top surface of said semiconductor substrate, and the bottom of said heavily doped source and drain region;
- an ultra lightly doped source and drain region, the same conductivity type as said heavily doped source and drain region, in said peripheral channel region, to a depth of about one half the depth of said pocket ion implanted region;
- an ultra shallow junction extension region, in said peripheral channel region, to a depth of about one half the depth of said ultra lightly doped source and drain region, with same conductivity type as said ultra lightly doped source and drain region;
- an insulator layer on the top surface of said semiconductor substrate, including said insulator layer on said polysilicon gate structure, on said metal silicide on said heavily doped source and drain region;
- contact holes, in said insulator layer, to said metal silicide on said heavily doped source and drain regions, and to said metal silicide on said polysilicon gate structure;
- and
- an metal interconnect structure, contacting said heavily doped source and drain region, and said polysilicon gate structure, in said contact hole.
Dependencies are inferred from the claim text.