Tungsten silicide deposition process
First Claim
Patent Images
1. A method of forming a gate electrode in a semiconductor integrated circuit device, comprising the steps of:
- forming a silicon layer over a gate dielectric layer on a substrate;
forming a tungsten layer by replacing silicon atoms in the silicon layer with tungsten atoms by a displacement reaction prior to patterning the gate electrode; and
annealing said substrate so as to react a substantial portion of said tungsten layer with underlying silicon to form a tungsten silicide layer.
2 Assignments
0 Petitions
Accused Products
Abstract
A method of forming a gate metallization in a semiconductor integrated circuit by forming a polycrystalline silicon layer over a gate dielectric layer and then converting the polycrystalline silicon layer into tungsten or tungsten silicide by exposing the polycrystalline silicon to tungsten hexafluoride gas. The method enables the formation of polycrystalline silicon and tungsten or tungsten silicide in the same process cycle in the same reactor or in two similarly configured reactors or in two similarly configured clustered reactors.
225 Citations
37 Claims
-
1. A method of forming a gate electrode in a semiconductor integrated circuit device, comprising the steps of:
-
forming a silicon layer over a gate dielectric layer on a substrate;
forming a tungsten layer by replacing silicon atoms in the silicon layer with tungsten atoms by a displacement reaction prior to patterning the gate electrode; and
annealing said substrate so as to react a substantial portion of said tungsten layer with underlying silicon to form a tungsten silicide layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A method of forming a gate electrode in a semiconductor integrated circuit device, comprising the steps of:
-
forming a silicon layer over a gate dielectric layer on a substrate;
forming a tungsten silicide layer by replacing silicon atoms in the silicon layer with tungsten and silicon atoms by a displacement reaction prior to patterning the gate electrode, and patterning said silicon and tungsten silicide layers to form the gate electrode. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31)
-
-
32. A process of forming a gate electrode on a semiconductor substrate, comprising:
-
depositing a silicon layer on a substrate in a reactor chamber; and
replacing at least a portion of silicon atoms in the silicon layer with atoms to form a metallic layer comprising tungsten by direct substitution within the same reactor chamber, wherein the metallic layer comprises tungsten silicide. - View Dependent Claims (33)
-
-
34. A method of forming a gate stack over a semiconductor substrate, comprising:
-
forming a gate dielectric layer on the semiconductor substrate;
depositing a silicon layer directly over the gate dielectric layer with the substrate positioned in a chemical vapor deposition chamber;
selectively depositing a tungsten layer on the silicon layer with the substrate positioned in a chamber of substantially the same configuration;
annealing to react the tungsten layer with underlying silicon to form a tungsten silicide layer; and
patterning the gate stack after selectively depositing. - View Dependent Claims (35, 36)
-
-
37. A process of forming a gate electrode on a semiconductor substrate, comprising:
-
depositing a silicon layer on a substrate in a reactor chamber;
replacing at least a substantial portion of the silicon atoms in the silicon layer with tungsten atoms by direct substitution prior to patterning the gate electrode;
annealing the silicon and elemental tungsten layers to form a tungsten silicide layer.
-
Specification