EP0751567A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Copper alloys for chip and package interconnections and method of making
Assignee: International Business Machines Corp
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Filing: 1996-06-12
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Granted: —
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Expires: 2016-06-12
Abstract
Abstract Copper alloys containing between 0.01 and 10 weight percent of at least one alloying element selected from carbon, indium and tin for improved electromigration resistance, low resistivity and good corrosion resistance that can be used in chip and package interconnections and a method of making such 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 C. 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
EP
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: 25
Claim 1
Independent Claim
34 words
An interconnection structure for providing electrical connections comprising copper and between about 0.01 and about 10 weight percent of at least one alloying element selected from the group consisting of carbon, tin and indium.
Claim 2
Dependent Claim
59 words
An interconnection structure according to claim 1, wherein said structure further comprises a multiplicity of grains separated by grain boundaries wherein each of said grains having a concentration of said at least one alloying element at or near said grain boundaries at least 120% that at locations inside the grains which are situated substantially away from the grain boundaries.
Claim 3
Dependent Claim
16 words
An interconnection structure according to claim 1, wherein said structure is used either on-chip or off-chip.
Claim 4
Dependent Claim
34 words
An interconnection structure according to claim 1, wherein said structure is a member selected from the group consisting of a via, a line, a stud, and a wiring lead for TAB, BGA or PGA.
Claim 5
Dependent Claim
38 words
An interconnection structure according to claim 1, wherein said at least one alloying element is carbon at a concentration of between about 0.01 and about 10 weight percent, preferably of between about 0.01 and about 2 weight percent.
Claim 6
Dependent Claim
42 words
An interconnection structure according to claim 1, wherein said at least one alloying element is tin at a concentration of between about 0.55 and about 10 weight percent, and preferably at a concentration of between about 0.55 and about 2.55 weight percent.
Claim 7
Dependent Claim
42 words
An interconnection structure according to claim 1, wherein said at least one alloying element is indium 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 8
Dependent Claim
32 words
An interconnection structure according to claim 1, wherein said structure is formed of a copper alloy having grain boundaries between the grains that are saturated with said at least one alloying element.
Claim 9
Dependent Claim
20 words
An interconnection structure according to claim 1, wherein said structure has improved electromigration resistance, low resistivity and good corrosion resistance.
Claim 10
Dependent Claim
26 words
An interconnection structure according to claim 1, wherein said structure further comprising a liner of adhesion/diffusion barrier layer made of a refractory metal or its nitride.
Claim 11
Dependent Claim
36 words
An interconnection structure according to claim 1, wherein said structure further comprises insulating layers of a dielectric material selected from the group consisting of silicon dioxide, silicon nitride, spin-on glass, flowable oxides, diamond-like carbon and polymers.
Claim 12
Dependent Claim
49 words
An interconnection structure according to claim 1, wherein said copper alloy is deposited 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 13
Dependent Claim
20 words
An interconnection structure according to claim 1, wherein said structure is a multilevel structure having between 3 and 7 levels.
Claim 14
Dependent Claim
20 words
An interconnection structure according to claim 1, wherein said structure is built on a previously deposited layer of metal silicide.
Claim 15
Dependent Claim
16 words
An interconnection structure according to claim 1, wherein said structure is built on a semiconductor device.
Claim 16
Dependent Claim
23 words
An interconnection structure according to claim 1, wherein said structure is connected to metal silicide through contact holes by a Ti/TiN/CVD W stud.
Claim 17
Dependent Claim
20 words
An interconnection structure according to claim 1, wherein said structure is connected to another metal of W or Al (Cu).
Claim 18
Dependent Claim
33 words
A conductor comprising an interconnection structure according to any one of the preceidng claims such that the conductor is capable of sustaining a current flow of at least 10 5 Amp/cm 2 .
Claim 19
Dependent Claim
31 words
A conductor according to claim 18, wherein said conductor is formed of a copper alloy having grain boundaries between the grains that are saturated with said at least one alloying element.
Claim 20
Independent Claim
129 words
A method of forming a conductor according to claims 18 or 19 comprising the steps of: forming a conductor by copper and at least one alloying element selected from the group consisting of carbon, tin and indium, said at least one alloying element account for between about 0.01 and about 10 weight percent of the total weight and is substantially uniformly distributed in the grains and within the grain boundaries of the copper alloy, and heating said conductor at 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 21
Dependent Claim
59 words
The method of claim 2, wherein said conductor is heated at a temperature of no less than 150°F 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% that at areas not substantially adjacent to said grain boundaries.
Claim 22
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 23
Dependent Claim
15 words
A method according to claim 22, wherein said temperature for annealing is at least 150°C.
Claim 24
Dependent Claim
16 words
An interconnection structure according to claim 1, wherein said structure is built on a display device.
Claim 25
Dependent Claim
15 words
A conductor according to claim 18, wherein said conductor is built on a display device.
References Cited (Backward Citations)
No citation records indexed.
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