US6090710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making copper alloys for chip and package interconnections
Assignee: GlobalFoundries Inc
•
Filing: 1997-08-15
•
Granted: 2000-07-18
•
Expires: 2017-08-15
Abstract
Abstract A method of making Copper alloys containing between 0.01 and 10 weight percent of at least one alloying element selected from carbon, indium and tin is disclosed for improved electromigration resistance, low resistivity and good corrosion resistance that can be used in chip and package interconnections and conductors by first forming the copper alloy and then annealing it to cause the diffusion of the alloying element toward the grain boundaries between the grains in the alloy are disclosed.
Inventors
- 👤 Panayotis Constantinou Andricacos
- 👤 Hariklia Deligianni
- 👤 James Mckell Edwin Harper
- 👤 Chao-Kun Hu
- 👤 Dale Jonathan Pearson
- 👤 Scott Kevin Reynolds
- 👤 King-Ning Tu
- 👤 Cyprian Emeka Uzoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:23
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/60; H10W70/62; H10W70/66; H10P; H10P14/00; H10P14/40; H10P14/42; H10W20/00; H10W20/01; H10W20/031; H10W20/056; H10W20/063; H10W20/0633; H10W20/064; H10W20/071; H10W20/074; H10W20/077; H10W20/40; H10W20/41; H10W20/425; H10W20/44; H10W20/4403; H10W20/4421; H10W20/4424; H10W20/45; H10W20/48; H10W70/67; H10W70/68; H10W70/685; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
134 words
A method of forming a conductor comprising the steps of: forming a conductor by copper and at least one alloying element selected from the group consisting of between about 0.01 and about 10 wt % carbon, between about 0.6 and about 1.8 wt % tin and between about 0.6 and about 10 wt % indium of the total weight of the conductor and is substantially uniformly distributed in the grains and within the grain boundaries of the copper alloy, and heating said conductor to a temperature and for a length of time that is sufficient to cause a thermally induced diffusion process of said at least one alloying element to move toward said grain boundaries such that there is a saturation of said at least one alloying element at or near said grain boundaries.
Claim 2
Independent Claim
134 words
A method of forming a conductor comprising the steps of: forming a conductor by copper and at least one alloying element selected from the group consisting of between about 0.01 and about 10 wt % carbon, between about 0.6 and about 1.8 wt % tin and between about 0.6 and about 10 wt % indium of the total weight of the conductor and is substantially uniformly distributed in the grains and within the grain boundaries of the copper alloy, and heating said conductor to a temperature and for a length of time that is sufficient to cause a thermally induced diffusion process of said at least one alloying element to move toward said grain boundaries such that there is a saturation of said at least one alloying element at or near said grain boundaries.
Claim 3
Dependent Claim
45 words
A method according to claim 1, wherein said conductor after heating is formed of a copper alloy having at its grain boundaries a concentration of said at least one alloying element that is at least 120% at areas not substantially adjacent to said grain boundaries.
Claim 4
Dependent Claim
26 words
A method according to claim 1, wherein said at least one element is carbon at a concentration of between about 0.01 and about 10 weight percent.
Claim 5
Dependent Claim
27 words
A method according to claim 1, wherein said at least one alloying element is tin at a concentration of between about 0.55 and about 1.8 weight percent.
Claim 6
Dependent Claim
27 words
A method according to claim 1, wherein said at least one alloying element is indium at a concentration of between about 0.06 and about 10 weight percent.
Claim 7
Dependent Claim
26 words
A method according to claim 1, wherein said conductor further comprises a liner of an adhesion/diffusion barrier layer made of a refractory metal or its nitride.
Claim 8
Dependent Claim
48 words
A method according to claim 1, wherein said copper alloy is formed by a process selected from the group consisting of collimated sputtering, evaporation, ion cluster beam deposition, electron cyclotron resonance deposition, ionized sputter deposition, chemical vapor deposition, electroless plating, electrolytic plating, co-evaporation, co-chemical vapor deposition and co-sputtering.
Claim 9
Dependent Claim
19 words
A method according to claim 1, wherein said conductor is built on a previously deposited layer of metal silicide.
Claim 10
Dependent Claim
15 words
A method according to claim 1, wherein said conductor is built on a semiconductor device.
Claim 11
Independent Claim
135 words
A method of forming a conductor for providing electrical connections comprising the steps of: forming a conductor of copper alloy containing one alloying element selected from the group consisting of between about 0.01 and about 10 wt % carbon, between about 0.6 and about 1.8 wt % tin and between about 0.6 and about 10 wt % indium of the total weight of the conductor and is substantially uniformly distributed in the grains and within the grain boundaries of said copper alloy, and heating said conductor at a temperature of no less than 150° C. to cause a diffusion process of said alloying element toward said grain boundaries such that the concentration of said alloying element at or near said grain boundaries is at least 120% at areas not substantially adjacent to said grain boundaries.
Claim 12
Independent Claim
135 words
A method of forming a conductor for providing electrical connections comprising the steps of: forming a conductor of copper alloy containing one alloying element selected from the group consisting of between about 0.01 and about 10 wt % carbon, between about 0.6 and about 1.8 wt % tin and between about 0.6 and about 10 wt % indium of the total weight of the conductor and is substantially uniformly distributed in the grains and within the grain boundaries of said copper alloy, and heating said conductor at a temperature of no less than 150° C. to cause a diffusion process of said alloying element toward said grain boundaries such that the concentration of said alloying element at or near said grain boundaries is at least 120% at areas not substantially adjacent to said grain boundaries.
Claim 13
Dependent Claim
39 words
A method according to claim 10, wherein said one alloying element is carbon at a concentration of between about 0.01 and about 10 weight percent, and preferably at a concentration of between about 0.01 and about 2 weight percent.
Claim 14
Dependent Claim
27 words
A method according to claim 10, wherein said at least one alloying element is tin at a concentration of between about 0.55 and about 1.8 weight percent.
Claim 15
Dependent Claim
27 words
A method according to claim 10, wherein said at least one alloying element is indium at a concentration of between about 0.6 and about 10 weight percent.
Claim 16
Dependent Claim
47 words
A method according to claim 10, wherein said conductor is formed by a process selected from the group consisting of collimated sputtering, evaporation, ion cluster beam deposition, electron cyclotron resonance deposition, ionized sputter deposition, chemical vapor deposition, electroless plating, electrolytic plating, co-evaporation, co-chemical vapor deposition and co-sputtering.
Claim 17
Independent Claim
67 words
A method for reducing electromigration in copper comprising the steps of: depositing a first layer of copper, depositing a second layer of a material selected from the group consisting of carbon, tin and indium over at least a portion of said first layer, and annealing said layers at a temperature sufficient to form a solid solution of said two layers containing at least 90 weight percent copper.
Claim 18
Independent Claim
67 words
A method for reducing electromigration in copper comprising the steps of: depositing a first layer of copper, depositing a second layer of a material selected from the group consisting of carbon, tin and indium over at least a portion of said first layer, and annealing said layers at a temperature sufficient to form a solid solution of said two layers containing at least 90 weight percent copper.
Claim 19
Dependent Claim
16 words
A method according to claim 15, wherein said temperature for annealing is at least 150° C.
References Cited (Backward Citations)
US4120758A
Cited
US4400351A
Cited
US4388346A
Cited
US4443274A
Cited
US4511410A
Cited
US4586967A
Cited
US4612411A
Cited
US4798660A
Cited
US4749548A
Cited
US4830933A
Cited
US5021105A
Cited
US5004520A
Cited
JPS63266052A
Cited
JPS6456842A
Cited
EP0335383A2
Cited
US5023698A
Cited
US4915745A
Cited
US4915745B1
Cited
US5077005A
Cited
EP0460454A1
Cited
US5221411A
Cited
US5821627A
Cited
US5391517A
Cited
US5656860A
Cited
US5780172A
Cited
US5916695A
Cited
US6010960A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-07-18 | 2004-01-17 | 2004-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-18 | 2008-01-17 | 2008-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-18 | 2012-01-17 | 2012-07-18 | $7700.00 | Window Closed / Lapsed |