EP0652588A2
Expired / Lapsed
EP
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Process for etching conductor layers in integrated circuits
Assignee: AT&T Inc
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Filing: 1994-10-26
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Granted: —
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Expires: 2014-10-26
Abstract
Abstract A method for etching metal conductors and stacks of conductors is disclosed. A doped silicon dioxide layer (e.g., 15) is deposited upon a metal (e.g., 13) or stack of conductive layers to be etched with phosphorous. Next, the silicon dioxide layer (e.g., 15) is partially etched and the photoresist removed. Subsequent etching utilizes the raised feature created in the silicon dioxide layer (e.g., 15) as a mask to etch the underlying metal (e.g., 13) or stack of conductors.
Inventors
- 👤 Sailesh Chittipeddi
- 👤 William Thomas Cochran
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 21:23
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/71; H10P76/00; H10P76/40; H10P76/408
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
109 words
A method of integrated circuit fabrication comprising: forming at least one conductive layer overlying a substrate (e.g., 11); forming a layer of material (e.g., 15) overlying said conductive layer (e.g., 13); forming a patterned photoresist (e.g., 17) upon said layer of material (e.g., 15); AND CHARACTERIZED BY using said patterned photoresist (e.g., 17) as a first mask, etching at least partially through said layer of material (e.g., 15), thereby forming a raised feature (e.g., 19); removing said photoresist; using said raised feature (e.g., 19) as a mask, etching said conductive layer (e.g., 13), thereby forming a raised conductive feature upon said substrate; and removing said raised feature (e.g., 19).
Claim 2
Independent Claim
109 words
A method of integrated circuit fabrication comprising: forming at least one conductive layer overlying a substrate (e.g., 11); forming a layer of material (e.g., 15) overlying said conductive layer (e.g., 13); forming a patterned photoresist (e.g., 17) upon said layer of material (e.g., 15); AND CHARACTERIZED BY using said patterned photoresist (e.g., 17) as a first mask, etching at least partially through said layer of material (e.g., 15), thereby forming a raised feature (e.g., 19); removing said photoresist; using said raised feature (e.g., 19) as a mask, etching said conductive layer (e.g., 13), thereby forming a raised conductive feature upon said substrate; and removing said raised feature (e.g., 19).
Claim 3
Dependent Claim
26 words
The method of claim 1 in which said conductive material (e.g., 13) is chosen from the group consisting of copper, aluminum, tungsten and refractory metal silicide.
Claim 4
Dependent Claim
41 words
The method of claim 1 in which an anti-reflective coating (e.g., 37) is formed between said conductive layer (e.g., 35, 33) and said layer of material (e.g., 15), and said anti-reflective coating (e.g., 37) is etched prior to said conductive layer.
Claim 5
Dependent Claim
24 words
The method of claim 3 in which said anti-reflective coating (e.g., 37) is chosen from the group consisting of titanium nitride and titanium tungsten.
Claim 6
Dependent Claim
37 words
The method of claim 1 in which a layer of titanium nitride (e.g., 33) is formed between said layer of conductive material and said substrate and said layer of titanium nitride is etched after said conductive layer.
Claim 7
Dependent Claim
43 words
The method of claim 5 in which a layer of titanium (e.g., 31) is formed between said layer of titanium nitride (e.g., 33) and said substrate and said layer of titanium (e.g., 31) is etched after said layer of titanium nitride (e.g., 33).
Claim 8
Dependent Claim
31 words
The method of claim 1 in which said layer of material (e.g., 15) is chosen from the group consisting of oxide doped with phosphorous, BPTEOS, BPSG, PSG, PPETEOS and spin-on glass.
Claim 9
Dependent Claim
50 words
The method of claim 1 in which said material layer (e.g., 15) is a bilayer and said bilayer is chosen from the group consisting of: plasma-enhanced undoped silicon oxide under plasma-enhanced phosphorous doped silicon oxide; silicon nitride under plasma-enhanced doped silicon oxide; and undoped silicon oxide under doped silicon oxide.
Claim 10
Dependent Claim
24 words
The method of claim 1 in which said material layer (e.g., 15) is a silicon oxide whose doping gradually increases from bottom to top.
References Cited (Backward Citations)
No citation records indexed.
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