US5639316A
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Thin film multi-layer oxygen diffusion barrier consisting of aluminum on refractory metal
Assignee: International Business Machines Corp
•
Filing: 1995-06-06
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Granted: 1997-06-17
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Expires: 2015-06-06
Abstract
Abstract The use of a bi-layer thin film structure consisting of aluminum or aluminide on a refractory metal layer as a diffusion barrier to oxygen penetration at high temperatures for preventing the electrical and mechanical degradation of the refractory metal for use in applications such as a capacitor electrode for high dielectric constant materials.
Inventors
- 👤 Cyril Cabral, Jr.
- 👤 Evan George Colgan
- 👤 Alfred Grill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:35
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/011; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/047; H10W20/049; H10D1/00; H10D1/60; H10D1/68; H10D1/692; H10D1/696; H10W20/40; H10W20/41; H10W20/425; H10D1/682
Claims Analysis
Total Claims: 48
Claim 1
Independent Claim
80 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 2
Independent Claim
80 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 3
Dependent Claim
29 words
A method according to claim 1, wherein the refractory metal is a metal selected from the group consisting of Ta, Ti, Nb, V, Zr, Hf, Cr, Mo and W.
Claim 4
Independent Claim
84 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate of either SiO 2 or Si 3 N 4 , depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 5
Independent Claim
84 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate of either SiO 2 or Si 3 N 4 , depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 6
Dependent Claim
30 words
A method according to claim 3, wherein the refractory metal and the aluminum are deposited by a physical vapor deposition technique, a chemical vapor deposition technique or an electroplating technique.
Claim 7
Independent Claim
92 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 8
Independent Claim
92 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 9
Dependent Claim
30 words
A method according to claim 5, wherein the refractory metal and the aluminum are deposited by a physical vapor deposition technique, a chemical vapor deposition technique or an electroplating technique.
Claim 10
Independent Claim
98 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate of either SiO 2 or Si 3 N 4 , depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory/aluminum bi-layer in He, Ar, N 2 , forming gas O 2 at temperatures above 250° C. such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 11
Independent Claim
98 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate of either SiO 2 or Si 3 N 4 , depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory/aluminum bi-layer in He, Ar, N 2 , forming gas O 2 at temperatures above 250° C. such that a top layer of Al 2 O 3 is formed on a refractory metal aluminide which is in contact with the refractory metal layer.
Claim 12
Independent Claim
100 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer between Si and a high dielectric constant material, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 13
Independent Claim
100 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer between Si and a high dielectric constant material, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 14
Dependent Claim
33 words
A method according to claim 8, wherein the high dielectric constant material and the refractory metal/aluminum bi-layer deposited on a Si substrate are annealed in oxygen at temperatures between 400° and 800° C.
Claim 15
Independent Claim
146 words
A method of using a self-aligned process to form gate lines or metal contacts and to protect a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal and patterning the layer into refractory metal lines or contact paths, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, annealing above 400° C. such that the Al in contact with the refractory metal forms an aluminide, annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide, and selectively etching the unreacted Al in areas where no refractory metal is present.
Claim 16
Independent Claim
146 words
A method of using a self-aligned process to form gate lines or metal contacts and to protect a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal and patterning the layer into refractory metal lines or contact paths, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, annealing above 400° C. such that the Al in contact with the refractory metal forms an aluminide, annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide, and selectively etching the unreacted Al in areas where no refractory metal is present.
Claim 17
Independent Claim
102 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer for use as a diffusion barrier between Si and Cu, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 18
Independent Claim
102 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer for use as a diffusion barrier between Si and Cu, and annealing the refractory metal/aluminum bi-layer such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide.
Claim 19
Independent Claim
81 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum such that a layer of Al 2 O 3 is formed on top of said aluminum layer to prevent oxygen diffusion through said refractory metal layer.
Claim 20
Independent Claim
81 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum such that a layer of Al 2 O 3 is formed on top of said aluminum layer to prevent oxygen diffusion through said refractory metal layer.
Claim 21
Dependent Claim
29 words
A method according to claim 12, wherein the refractory metal is a metal selected from the group consisting of Ta, Ti, Nb, V, Zr, Hf, Cr, Mo and W.
Claim 22
Independent Claim
77 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 23
Independent Claim
77 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 24
Dependent Claim
38 words
A method according to claim 14, wherein said refractory metal and said aluminum are deposited by a technique selected from the group consisting of a physical vapor deposition technique, a chemical vapor deposition technique and an electroplating technique.
Claim 25
Independent Claim
102 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 26
Independent Claim
102 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 27
Dependent Claim
38 words
A method according to claim 16, wherein said refractory metal and said aluminum are deposited by a technique selected from the group consisting of a physical vapor deposition technique, a chemical vapor deposition technique and an electroplating technique.
Claim 28
Independent Claim
92 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film, and annealing the layers of the refractory metal film and the aluminum film in He, Ar, N 2 , FG or O 2 at temperatures above 250° C. such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 29
Independent Claim
92 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film, and annealing the layers of the refractory metal film and the aluminum film in He, Ar, N 2 , FG or O 2 at temperatures above 250° C. such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 30
Independent Claim
97 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film forming a refractory metal/aluminum bi-layer wherein the refractory metal/aluminum bi-layer is deposited between Si and a high dielectric constant material, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 31
Independent Claim
97 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film forming a refractory metal/aluminum bi-layer wherein the refractory metal/aluminum bi-layer is deposited between Si and a high dielectric constant material, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 32
Dependent Claim
32 words
A method according to claim 19, wherein said high dielectric constant material is a Perovskite compound selected from the group consisting of PZT, PLZT and Ba x Sr 1-x TiO 3 .
Claim 33
Independent Claim
90 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum in oxygen at temperatures between 400° and 800° C. such that a layer of Al 2 O 3 is formed on top of said aluminum layer to prevent oxygen diffusion through said refractory metal layer.
Claim 34
Independent Claim
90 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate that is not a refractory metal, depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum in oxygen at temperatures between 400° and 800° C. such that a layer of Al 2 O 3 is formed on top of said aluminum layer to prevent oxygen diffusion through said refractory metal layer.
Claim 35
Independent Claim
97 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film forming a refractory metal/aluminum bi-layer wherein the refractory metal/aluminum bi-layer is used as a diffusion barrier between Si and Cu, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 36
Independent Claim
97 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film forming a refractory metal/aluminum bi-layer wherein the refractory metal/aluminum bi-layer is used as a diffusion barrier between Si and Cu, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 37
Independent Claim
104 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film wherein the refractory metal layer and the aluminum layer are deposited between Si and a metal seed layer on which a high dielectric constant material is deposited, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 38
Independent Claim
104 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate of a semiconducting material, depositing a refractory metal film overlying said substrate, depositing an aluminum film overlying said refractory metal film wherein the refractory metal layer and the aluminum layer are deposited between Si and a metal seed layer on which a high dielectric constant material is deposited, and annealing the layers of the refractory metal film and the aluminum film such that a layer of Al 2 O 3 is formed on top of said aluminum film to prevent oxygen diffusion through said refractory metal film.
Claim 39
Independent Claim
107 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer in He, Ar, N 2 , forming gas or O 2 at temperatures above 250° C. such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on refractory metal silicide.
Claim 40
Independent Claim
107 words
A method of protecting a refractory metal from oxidation during high temperature annealing comprising the steps of: providing a substrate made of a material selected from the group consisting of single crystal silicon, polycrystalline silicon, amorphous silicon and other semiconductor materials, depositing a layer of a refractory metal, depositing a layer of aluminum on the refractory metal layer forming a refractory metal/aluminum bi-layer, and annealing the refractory metal/aluminum bi-layer in He, Ar, N 2 , forming gas or O 2 at temperatures above 250° C. such that a final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on refractory metal silicide.
Claim 41
Independent Claim
118 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum in He, Ar, N 2 , forming gas or O 2 at temperatures above 250° C. such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 42
Independent Claim
118 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate, depositing a layer of aluminum on said layer of refractory metal, and annealing the layers of the refractory metal and the aluminum in He, Ar, N 2 , forming gas or O 2 at temperatures above 250° C. such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 43
Independent Claim
122 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate. depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum metal layer are deposited between Si and a high dielectric constant material, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 44
Independent Claim
122 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of a refractory metal on said substrate. depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum metal layer are deposited between Si and a high dielectric constant material, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 45
Independent Claim
111 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum layer are used as a diffusion barrier between Si and Cu, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 46
Independent Claim
111 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon. depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum layer are used as a diffusion barrier between Si and Cu, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 47
Independent Claim
119 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon, depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum layer are deposited between Si and a metal seed layer on which a high dielectric constant material is deposited, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
Claim 48
Independent Claim
119 words
A method of preventing oxygen diffusion in a semiconductor device comprising the steps of: providing a substrate made of a material selected from the group consisting of a single crystal silicon, a polycrystalline silicon and an amorphous silicon, depositing a layer of aluminum on said layer of refractory metal wherein the refractory metal layer and the aluminum layer are deposited between Si and a metal seed layer on which a high dielectric constant material is deposited, and annealing the layers of the refractory metal and the aluminum such that the final structure after annealing consists of Al 2 O 3 on a refractory metal aluminide on a refractory metal silicide to prevent oxygen diffusion through said refractory metal layer.
References Cited (Backward Citations)
US3420689A
Cited
US3939047A
Cited
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