US5244538A
Expired / Lapsed
US
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Method of patterning metal on a substrate using direct-write deposition of a mask
Assignee: Rateze Remote Mgmt LLC
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Filing: 1991-07-26
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Granted: 1993-09-14
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Expires: 2011-07-26
Abstract
Abstract A method of patterning metal on a substrate without photolithography. The steps include providing a dielectric substrate, forming a metal mask in a predetermined pattern on the substrate without using a mask by direct-write deposition using a particle beam such as a liquid metal cluster force to form the mask, dry etching the substrate to form a plurality of channels therein, depositing a conductive metal into the channels, and removing the mask. The top of the substrate can then be planarized by polishing, or alternatively the dielectric between the metal lines can be etched. The invention is well suited for fabricating copper/polyimide substrates.
Inventors
- 👤 Nalin Kumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:29
CPC Classifications
H; H10; H10W; H10W70/00; H10W70/01; H10W70/05; H05; H05K; H05K3/00; H05K3/02; H05K3/04; H05K3/045; H05K3/10; H05K3/18; H05K3/181; H05K3/182; H05K3/184; H05K3/46; H05K3/4644; H05K3/465; H01; H01J; H01J2201/00; H01J2201/30; H01J2201/304; H01J2201/30446; H01J2201/30453; H01J2201/30457; H05K2201/00; H05K2201/01; H05K2201/0137; H05K2201/0154; H05K2201/0166; H05K2201/03; H05K2201/0332; H05K2201/0364; H05K2201/0376; H05K2201/20; H05K2201/2081; H05K2203/00; H05K2203/05; H05K2203/0548; H05K2203/0554; H05K2203/10; H05K2203/107; H05K2203/12; H05K2203/121; H05K2203/13; H05K2203/1333; H05K2203/1338; H05K3/0011; H05K3/0017; H05K3/0023; H05K3/0041; H05K3/107; H05K3/14; H05K3/143; H05K3/146; H05K3/185; H05K3/38; H05K3/388; H05K3/4661
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
104 words
A method of patterning metal on a substrate, comprising the steps of: providing a dielectric substrate with a substantially planar top surface; forming a metal etch mask in a predetermined pattern on said surface of the substrate without using a mask by direct-write deposition using a particle beam of metal particles to form said etch mask, said pattern containing a plurality of openings which selectively expose portions of said substrate; dry etching said exposed portions to form a plurality of channels in said substrate; and depositing a conductive metal into said channels; wherein said patterned metal comprises said conductive metal without said etch mask.
Claim 2
Independent Claim
104 words
A method of patterning metal on a substrate, comprising the steps of: providing a dielectric substrate with a substantially planar top surface; forming a metal etch mask in a predetermined pattern on said surface of the substrate without using a mask by direct-write deposition using a particle beam of metal particles to form said etch mask, said pattern containing a plurality of openings which selectively expose portions of said substrate; dry etching said exposed portions to form a plurality of channels in said substrate; and depositing a conductive metal into said channels; wherein said patterned metal comprises said conductive metal without said etch mask.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said dielectric is a polymer.
Claim 4
Dependent Claim
10 words
The method of claim 1 wherein said polymer is polyimide.
Claim 5
Dependent Claim
17 words
The method of claim 1 wherein said direct-write deposition is performed by a liquid metal cluster source.
Claim 6
Dependent Claim
18 words
The method of claim 1 wherein said mask is removed from said substrate after the dry etching step.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein said mask is selected from the group consisting of gold, copper, aluminum, silver, tungsten and alloys thereof.
Claim 8
Dependent Claim
22 words
The method of claim 1 wherein said mask is gold and said direct-write deposition is performed by a liquid metal cluster source.
Claim 9
Dependent Claim
15 words
The method of claim 1 wherein said mask is approximately 300 to 2,000 angstroms thick.
Claim 10
Dependent Claim
29 words
The method of claim 1 wherein the etch rate of said mask is at least 10 times slower than the etch rate of said dielectric during the dry etching.
Claim 11
Dependent Claim
24 words
The method of claim 1 wherein said dry etching is performed by one of plasma etching, laser etching, reactive ion etching or ion milling.
Claim 12
Dependent Claim
15 words
The method of claim 1 wherein said dry etching is performed by anisotropic plasma etching.
Claim 13
Dependent Claim
19 words
The method of claim 1 wherein said conductive metal is selected from the group consisting of copper and aluminum.
Claim 14
Dependent Claim
11 words
The method of claim 1 wherein said conductive metal is copper.
Claim 15
Dependent Claim
15 words
The method of claim 13 wherein said copper is approximately 5 to 10 microns thick.
Claim 16
Dependent Claim
16 words
The method of claim 14 wherein said copper has an aspect ratio of at least 5.
Claim 17
Dependent Claim
19 words
The method of claim 1 wherein said mask is removed by wet chemical etching after the dry etching step.
Claim 18
Dependent Claim
28 words
The method of claim 16, further comprising planarizing said substrate by polishing after removing said mask so that said conductive metal is in and aligned with said surface.
Claim 19
Dependent Claim
16 words
The method of claim 16, further comprising performing each of said steps in a vacuum environment.
Claim 20
Dependent Claim
35 words
The method of claim 16, further comprising the step of etching the dielectric between lines of said conductive metal after removing said mask so that the lines of said conductive metal protrude above the substrate.
Claim 21
Dependent Claim
13 words
The method of claim 1 wherein said etch mask consists of said particles.
Claim 22
Independent Claim
130 words
A method of patterning copper lines in a polymer layer of a multilayer electrical interconnect, comprising: (a) direct-writing a metal etch mask in a predetermined pattern over a smooth top surface of a polymer layer on a substrate without using a mask, wherein said direct-writing is performed using a beam consisting of charged metal particles which form the entire etch mask, and said pattern contains a plurality of openings which selectively expose portions of said polymer; (b) applying an anisotropic dry etch to said exposed polymer portions through said openings to form a plurality of channels in said polymer which correspond to said openings; and (c) depositing copper into said channels, thereby forming a plurality of copper lines in a pattern corresponding to said openings of said predetermined mask pattern.
Claim 23
Independent Claim
130 words
A method of patterning copper lines in a polymer layer of a multilayer electrical interconnect, comprising: (a) direct-writing a metal etch mask in a predetermined pattern over a smooth top surface of a polymer layer on a substrate without using a mask, wherein said direct-writing is performed using a beam consisting of charged metal particles which form the entire etch mask, and said pattern contains a plurality of openings which selectively expose portions of said polymer; (b) applying an anisotropic dry etch to said exposed polymer portions through said openings to form a plurality of channels in said polymer which correspond to said openings; and (c) depositing copper into said channels, thereby forming a plurality of copper lines in a pattern corresponding to said openings of said predetermined mask pattern.
Claim 24
Dependent Claim
26 words
The method of claim 21, further comprising depositing an activator material into said channels between steps (b) and (c), and depositing said copper by electroless deposition.
Claim 25
Dependent Claim
11 words
The method of claim 22 wherein said activator material is tungsten.
Claim 26
Dependent Claim
19 words
The method of claim 21, further comprising depositing an adhesion metal into said channels between steps (b) and (c).
Claim 27
Dependent Claim
20 words
The method of claim 24 wherein said adhesion metal is selected from the group consisting of chromium, titanium and tantalum.
Claim 28
Dependent Claim
50 words
The method of claim 21, further comprising depositing a blanket layer of metal into said channels and over said mask between steps (b) and (c), applying a wet chemical etch to lift the mask off the substrate between steps (b) and (c), and then depositing said copper by electroless deposition.
Claim 29
Dependent Claim
38 words
The method of claim 21, further comprising (d) stripping said etch mask, and then (e) planarizing the top of the substrate by applying polishing, thereby forming a smooth top surface comprising the copper lines aligned with the polymer.
Claim 30
Dependent Claim
46 words
The method of claim 21, further comprising (d) stripping said etch mask by applying a wet chemical etch, and (e) applying a second wet chemical etch to remove the polymer between said copper lines, thereby forming copper lines which protrude above the top of said substrate.
Claim 31
Dependent Claim
20 words
The method of claim 28, wherein said copper lines protrude at least 5 microns above the top of said substrate.
Claim 32
Independent Claim
81 words
A method of patterning metal on a substrate, comprising the steps of: providing a dielectric substrate; forming an etch mask in a predetermined pattern on the substrate without using a mask by direct-write deposition using a liquid metal cluster source to form said etch mask, said pattern containing a plurality of openings which selectively expose portions of said substrate; dry etching said exposed portions to form a plurality of channels in said substrate; and depositing a conductive metal into said channels.
Claim 33
Independent Claim
81 words
A method of patterning metal on a substrate, comprising the steps of: providing a dielectric substrate; forming an etch mask in a predetermined pattern on the substrate without using a mask by direct-write deposition using a liquid metal cluster source to form said etch mask, said pattern containing a plurality of openings which selectively expose portions of said substrate; dry etching said exposed portions to form a plurality of channels in said substrate; and depositing a conductive metal into said channels.
Claim 34
Dependent Claim
17 words
The method of claim 2 wherein said dielectric is a polymer and said conductive metal is copper.
Claim 35
Independent Claim
57 words
A method of patterning metal on a substrate without photolithography, comprising the steps of: depositing a metal etch mask on a dielectric substrate without using a mask by direct-write using a particle beam to form said etch mask; dry etching the substrate to form a plurality of channels therein; and depositing a conductive metal into the channels.
Claim 36
Independent Claim
57 words
A method of patterning metal on a substrate without photolithography, comprising the steps of: depositing a metal etch mask on a dielectric substrate without using a mask by direct-write using a particle beam to form said etch mask; dry etching the substrate to form a plurality of channels therein; and depositing a conductive metal into the channels.
Claim 37
Independent Claim
110 words
A method of patterning copper on a polymer substrate, comprising the steps of: providing a polymer substrate with a substantially planar top surface; depositing an etch mask in a predetermined pattern on said surface without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam and said pattern contains a plurality of openings which selectively expose portions of said surface; anisotropically dry etching said exposed portions to form a plurality of channels in said substrate; and depositing copper into said channels; wherein said patterned copper comprises said deposited copper without said etch mask.
Claim 38
Independent Claim
110 words
A method of patterning copper on a polymer substrate, comprising the steps of: providing a polymer substrate with a substantially planar top surface; depositing an etch mask in a predetermined pattern on said surface without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam and said pattern contains a plurality of openings which selectively expose portions of said surface; anisotropically dry etching said exposed portions to form a plurality of channels in said substrate; and depositing copper into said channels; wherein said patterned copper comprises said deposited copper without said etch mask.
Claim 39
Independent Claim
148 words
A method of patterning copper lines on a polymer substrate, comprising the following steps in the sequence set forth: providing a polymer substrate with a substantially planar top surface; depositing a metal etch mask approximately 300 to 2,000 angstroms thick in a predetermined pattern on said surface of the polymer without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam, and said pattern contains a plurality of openings which selectively expose portions of said polymer; anistropically dry etching said exposed portions to form a plurality of channels at least 5 microns deep in said polymer; depositing copper into said channels; and wet chemical etching said mask, thereby forming copper lines at least 5 microns thick with a configuration corresponding to said openings in said predetermined pattern and in said polymer.
Claim 40
Independent Claim
148 words
A method of patterning copper lines on a polymer substrate, comprising the following steps in the sequence set forth: providing a polymer substrate with a substantially planar top surface; depositing a metal etch mask approximately 300 to 2,000 angstroms thick in a predetermined pattern on said surface of the polymer without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam, and said pattern contains a plurality of openings which selectively expose portions of said polymer; anistropically dry etching said exposed portions to form a plurality of channels at least 5 microns deep in said polymer; depositing copper into said channels; and wet chemical etching said mask, thereby forming copper lines at least 5 microns thick with a configuration corresponding to said openings in said predetermined pattern and in said polymer.
Claim 41
Independent Claim
167 words
A method of patterning copper lines above a polymer substrate, comprising the following steps in the sequence set forth: providing a polymer substrate with a substantially planar top surface; depositing a metal etch mask approximately 300 to 2,000 angstroms thick in a predetermined pattern on said surface of the polymer without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam, and said pattern contains a plurality of openings which selectively expose portions of said polymer; anisotropically dry etching said exposed portions to form a plurality of channels at least 5 microns deep in said polymer; depositing copper into said channels; applying a first wet chemical etch to remove said mask; and applying a second wet chemical etch to remove the polymer between the copper, thereby forming copper lines at least 5 microns thick with a configuration corresponding to said openings in said predetermined pattern and protruding above said polymer.
Claim 42
Independent Claim
167 words
A method of patterning copper lines above a polymer substrate, comprising the following steps in the sequence set forth: providing a polymer substrate with a substantially planar top surface; depositing a metal etch mask approximately 300 to 2,000 angstroms thick in a predetermined pattern on said surface of the polymer without using a mask by direct-write from a liquid metal cluster source, wherein said etch mask is formed from particles provided by the liquid metal cluster source beam, and said pattern contains a plurality of openings which selectively expose portions of said polymer; anisotropically dry etching said exposed portions to form a plurality of channels at least 5 microns deep in said polymer; depositing copper into said channels; applying a first wet chemical etch to remove said mask; and applying a second wet chemical etch to remove the polymer between the copper, thereby forming copper lines at least 5 microns thick with a configuration corresponding to said openings in said predetermined pattern and protruding above said polymer.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-09-13 | 1997-03-15 | 1997-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-13 | 2001-03-15 | 2001-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-13 | 2005-03-15 | 2005-09-14 | $7700.00 | Window Closed / Lapsed |