US6350667B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of improving pad metal adhesion
Assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
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Filing: 1999-11-01
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Granted: 2002-02-26
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Expires: 2019-11-01
Abstract
Abstract The present invention is a new and improved method for fabricating aluminum metal pad structures wherein a thin adhesion layer of aluminum is placed in between the underlying copper metal and the top tantalum nitride pad barrier layer providing improved adhesion to the pad metal stack structure. In summary, present invention teaches a method comprising of forming a copper underlayer, forming the key aluminum adhesion layer, forming the tantalum nitride barrier layer, and finally forming the aluminum pad. The problem of adhesion of metal pad to underlying layers, dielectrics, and polymers in is not unique to the manufacture of multi-layer electronic circuit chips and modules, but is encountered in other technologies involved in other types of electronic elements, e.g., the formation of capacitors or even other technologies entirely unrelated to the fabrication of electrical devices. However, since the problems of loss of adhesion are of substantial economic importance at present in the fabrication of multi-layer chips and modules, the present invention is directed to silicon chip technology and IC modules, but can be easily applied to other technologies using these metal pad materials, special (stack) structures.
Inventors
- 👤 Sheng-Hsiung Chen
- 👤 Fan Keng Yang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:53
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; H10W20/037; H10W20/047; H10W20/049; H10W72/00; H10W72/01; H10W72/012; H10W72/019; H10W72/20; H10W72/251; H10W72/29; H10W72/50; H10W72/531; H10W72/5363; H10W72/551; H10W72/552; H10W72/5522; H10W72/5524; H10W72/5525; H10W72/59; H10W72/90; H10W72/921; H10W72/923; H10W72/951; H10W72/952
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
206 words
A method of fabricating multi-level interconnects in an integrated circuit and other devices on a substrate, the method comprising the steps of: (a) providing a substrate or a module; (b) providing said substrate with a layer of an interlevel dielectric over the substrate; (c) providing a first level metal wiring layer being defined and embedded in a first layer of insulator over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level metal wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level metal wiring layer; (f) depositing an adhesion layer over said first level metal wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing a metal layer for metal pad formation over said metal barrier layer; (k) patterning and defining said metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and interconnects and form metal pad contact structures for chips and IC's; wherein said adhesion layer is aluminum from about 50 to 80 Angstroms thick.
Claim 2
Independent Claim
206 words
A method of fabricating multi-level interconnects in an integrated circuit and other devices on a substrate, the method comprising the steps of: (a) providing a substrate or a module; (b) providing said substrate with a layer of an interlevel dielectric over the substrate; (c) providing a first level metal wiring layer being defined and embedded in a first layer of insulator over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level metal wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level metal wiring layer; (f) depositing an adhesion layer over said first level metal wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing a metal layer for metal pad formation over said metal barrier layer; (k) patterning and defining said metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and interconnects and form metal pad contact structures for chips and IC's; wherein said adhesion layer is aluminum from about 50 to 80 Angstroms thick.
Claim 3
Dependent Claim
23 words
The method of claim 1 , wherein said substrate is a semiconductor consisting of a single crystal of silicon or an IC module.
Claim 4
Dependent Claim
28 words
The method of claim 1 , wherein said layers of dielectric are selected from the group consisting of insulating, refractory materials, silicon oxide, silicon nitride and silicon oxynitride.
Claim 5
Dependent Claim
20 words
The method of claim 1 , wherein said layer of first level metal wiring is composed of conducting metal copper.
Claim 6
Dependent Claim
23 words
The method of claim 1 , wherein the metal barrier layer is composed of tantalum nitride, with a thickness of approximately 150 Angstroms.
Claim 7
Dependent Claim
21 words
The method of claim 1 , wherein said metal layer for metal pad formation over the metal barrier layer is aluminum.
Claim 8
Dependent Claim
46 words
The method of claim 1 , wherein the metal pad contact structure formation comprises: forming a copper layer, forming an aluminum adhesion layer over the copper layer, forming a tantalum nitride barrier layer over the adhesion layer, and forming an aluminum pad over the barrier layer.
Claim 9
Dependent Claim
35 words
The method of claim 1 , wherein the metal pads are made by a process that yields improved adhesion and conductivity, as proven by stress tests that confirmed adhesion properties by wire bond pull tests.
Claim 10
Dependent Claim
37 words
The method of claim 1 , wherein the metal pads formed for contact in applications selected from the group consisting of chip technology, IC module technology, and solid state devices where an integrated electrical contact is necessary.
Claim 11
Dependent Claim
24 words
The method of claim 1 further comprising: repeating the steps from (a) to (l) to form additional levels of multilevel metal pads and interconnects.
Claim 12
Independent Claim
225 words
A method of fabricating an integrated circuit on a substrate, using aluminum metal pad structures wherein an adhesion layer of aluminum is produced, the method comprising the following steps: (a) providing a silicon substrate or an IC substrate module; (b) providing said substrate with a layer of interlevel dielectric over the substrate; (c) providing a first level copper conducting wiring layer being defined and embedded in a first layer of insulator, comprised of silicon oxide, over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level copper wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level copper wiring layer; (f) depositing an adhesion layer, comprised of aluminum, over said first level copper wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer, comprised of tantalum nitride, over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing an aluminum metal layer for metal pad formation over said barrier layer; (k) patterning and defining said aluminum metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and form metal pad contact structures for chips and IC's; wherein said adhesion layer is from about 50 to 80 Angstroms thick.
Claim 13
Independent Claim
225 words
A method of fabricating an integrated circuit on a substrate, using aluminum metal pad structures wherein an adhesion layer of aluminum is produced, the method comprising the following steps: (a) providing a silicon substrate or an IC substrate module; (b) providing said substrate with a layer of interlevel dielectric over the substrate; (c) providing a first level copper conducting wiring layer being defined and embedded in a first layer of insulator, comprised of silicon oxide, over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level copper wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level copper wiring layer; (f) depositing an adhesion layer, comprised of aluminum, over said first level copper wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer, comprised of tantalum nitride, over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing an aluminum metal layer for metal pad formation over said barrier layer; (k) patterning and defining said aluminum metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and form metal pad contact structures for chips and IC's; wherein said adhesion layer is from about 50 to 80 Angstroms thick.
Claim 14
Dependent Claim
23 words
The method of claim 11 , wherein said substrate is a semiconductor consisting of a single crystal of silicon or an IC module.
Claim 15
Dependent Claim
28 words
The method of claim 11 , wherein said layers of dielectric are selected from the group consisting of insulating, refractory materials, silicon oxide, silicon nitride and silicon oxynitride.
Claim 16
Dependent Claim
31 words
The method of claim 11 , wherein said layer of first level copper wiring is composed of conducting metal copper which reacts with the adhesion layer to form CuAl 2 .
Claim 17
Dependent Claim
18 words
The method of claim 11 , wherein the metal barrier layer has a thickness of approximately 150 Angstroms.
Claim 18
Dependent Claim
39 words
The method of claim 11 , wherein said aluminum metal layer for metal pad formation over the metal barrier layer has improved adhesion properties due to the adhesion layer which bonds both the copper wiring and barrier layers together.
Claim 19
Dependent Claim
52 words
The method of claim 11 , wherein the metal pad contact structure formation comprises: forming a copper layer, forming an aluminum adhesion layer over the copper layer, forming a tantalum nitride barrier layer of a thickness approximately 150 Angstroms over the adhesion layer, and forming an aluminum pad over the barrier layer.
Claim 20
Dependent Claim
35 words
The method of claim 11 , wherein the metal pads are made by a process that yields improved adhesion and conductivity, as proven by stress tests that confirmed adhesion properties by wire bond pull tests.
Claim 21
Dependent Claim
38 words
The method of claim 11 , wherein the metal pads are formed for contact in applications selected from the group consisting of chip technology, IC module technology, and solid state devices where an integrated electrical contact is necessary.
Claim 22
Dependent Claim
24 words
The method of claim 11 further comprising: repeating the steps from (a) to (l) to form additional levels of multilevel metal pads and interconnects.
Claim 23
Independent Claim
239 words
A method of fabricating an integrated circuit on a substrate, using a method for fabricating aluminum metallurgy pad structure layer and lines, vias and interconnect wiring for MOSFET CMOS, memory and logic devices, the method comprising the following steps: (a) providing a silicon substrate or an IC substrate module; (b) providing said substrate with a layer of an interlevel dielectric over the substrate; (c) providing a first level copper conducting wiring layer being defined and embedded in a first layer of insulator, comprised of silicon oxide, over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level copper wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level copper wiring layer; (f) depositing an adhesion layer, comprised of aluminum, over said first level copper wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer, comprised of tantalum nitride, over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing an aluminum metal layer for metal pad formation over said barrier layer; (k) patterning and defining said aluminum metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and form metal pad contact, lines and interconnect wiring for chips and IC's; wherein said adhesion layer is from about 50 to 80 Angstroms thick.
Claim 24
Independent Claim
239 words
A method of fabricating an integrated circuit on a substrate, using a method for fabricating aluminum metallurgy pad structure layer and lines, vias and interconnect wiring for MOSFET CMOS, memory and logic devices, the method comprising the following steps: (a) providing a silicon substrate or an IC substrate module; (b) providing said substrate with a layer of an interlevel dielectric over the substrate; (c) providing a first level copper conducting wiring layer being defined and embedded in a first layer of insulator, comprised of silicon oxide, over the layer of interlevel dielectric; (d) depositing a dielectric layer over the defined said first level copper wiring layer; (e) patterning and etching said dielectric layer to form an open contact region to the first level copper wiring layer; (f) depositing an adhesion layer, comprised of aluminum, over said first level copper wiring layer; (g) patterning and defining said adhesion layer, then without an intervening step; (h) depositing a metal barrier layer, comprised of tantalum nitride, over said adhesion layer; (i) patterning and defining said metal barrier layer; (j) depositing an aluminum metal layer for metal pad formation over said barrier layer; (k) patterning and defining said aluminum metal layer to form metal pads; (l) repeating the above steps from (a) to (k) to construct multilevel pads and form metal pad contact, lines and interconnect wiring for chips and IC's; wherein said adhesion layer is from about 50 to 80 Angstroms thick.
Claim 25
Dependent Claim
23 words
The method of claim 21 , wherein said substrate is a semiconductor consisting of a single crystal of silicon or an IC module.
Claim 26
Dependent Claim
28 words
The method of claim 21 , wherein said layers of dielectric are selected from the group consisting of insulating, refractory materials, silicon oxide, silicon nitride and silicon oxynitride.
Claim 27
Dependent Claim
32 words
The method of claim 21 , wherein said layer of first level copper wiring is composed of conducting metal copper which reacts with the aluminum adhesion layer to form CuAl 2 .
Claim 28
Dependent Claim
18 words
The method of claim 21 , wherein the metal barrier layer has a thickness of approximately 150 Angstroms.
Claim 29
Dependent Claim
39 words
The method of claim 21 , wherein said aluminum metal layer for metal pad formation over the metal barrier layer has improved adhesion properties due to the adhesion layer which bonds both the copper wiring and barrier layers together.
Claim 30
Dependent Claim
52 words
The method of claim 21 , wherein the metal pad contact formation comprises : forming a copper layer, forming an aluminum adhesion layer over the copper layer, forming a tantalum nitride barrier layer of a thickness approximately 150 Angstroms over the adhesion layer, and forming an aluminum pad over the barrier layer.
Claim 31
Dependent Claim
35 words
The method of claim 21 , wherein the metal pads are made by a process that yields improved adhesion and conductivity, as proven by stress tests that confirmed adhesion properties by wire bond pull tests.
Claim 32
Dependent Claim
38 words
The method of claim 21 , wherein the metal pads are formed for contact in applications selected from the group consisting of chip technology, IC module technology, and solid state devices where an integrated electrical contact is necessary.
Claim 33
Dependent Claim
26 words
The method of claim 21 further comprising: repeating the steps from (a) to (l) to form additional levels of multilevel metal pads, lines and interconnect wiring.
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