Nitride capped MOSFET for integrated circuits
First Claim
1. A lightly doped drain MOS FET integrated circuit device comprising:
- a pattern of gate electrode structures upon a semiconductor substrate which structures each have vertical sidewalls and includes a gate oxide, a polysilicon layer and a refractory metal silicide;
a first thin silicon nitride layer with a thickness in the range of 80 to 300 Angstroms over said each of said gate electrode structures, including said vertical sidewalls, and over the surface of said substrate;
a pattern of lightly doped regions in said substrate adjacent to said structures;
a dielectric spacer structure upon the sidewalls of each of said structures and over the adjacent portions of said substrate;
a pattern of heavily doped regions in said substrate adjacent to said dielectric spacer structure on the vertical sidewalls of said gate electrode structures, which form lightly doped drain source/drain structures of an MOS FET device;
a passivation layer over the said structures and appropriate electrical connecting structures thereover to electrically connect the said structure gate electrode structures and source/drain elements to form said integrated circuit device; and
wherein a second thin silicon nitride layer is formed over said spacer structures and over said substrate, and said passivation layer is formed over said second thin silicon nitride layer.
1 Assignment
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Accused Products
Abstract
A method is described for fabricating a lightly doped drain MOSFET integrated circuit device. The method begins by forming a pattern of gate electrode structures upon a semiconductor substrate which structures each includes a gate oxide, a polysilicon layer and a refractory metal silicide. A thin silicon nitride layer is formed over each of the structures and the exposed surfaces therebetween of the substrate. A pattern of lightly doped regions in the substrate is formed by ion implantation using the polycide gate structures as the mask. A dielectric spacer structure is formed upon the sidewalls of each of the polycide gate structures and over the adjacent portions of the substrate. A pattern of heavily doped regions in the substrate is formed by ion implantation using the polycide structures with spacer structures as the mask to produce the lightly doped drain source/drain structures of an MOSFET device. The integrated circuit device is completed by forming a passivation layer over the structures described and appropriate electrical connecting structures thereover to electrically connect the gate electrode structures and source/drain elements.
104 Citations
5 Claims
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1. A lightly doped drain MOS FET integrated circuit device comprising:
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a pattern of gate electrode structures upon a semiconductor substrate which structures each have vertical sidewalls and includes a gate oxide, a polysilicon layer and a refractory metal silicide; a first thin silicon nitride layer with a thickness in the range of 80 to 300 Angstroms over said each of said gate electrode structures, including said vertical sidewalls, and over the surface of said substrate;
a pattern of lightly doped regions in said substrate adjacent to said structures;a dielectric spacer structure upon the sidewalls of each of said structures and over the adjacent portions of said substrate; a pattern of heavily doped regions in said substrate adjacent to said dielectric spacer structure on the vertical sidewalls of said gate electrode structures, which form lightly doped drain source/drain structures of an MOS FET device; a passivation layer over the said structures and appropriate electrical connecting structures thereover to electrically connect the said structure gate electrode structures and source/drain elements to form said integrated circuit device; and wherein a second thin silicon nitride layer is formed over said spacer structures and over said substrate, and said passivation layer is formed over said second thin silicon nitride layer. - View Dependent Claims (2, 3, 4, 5)
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Specification