Patent EP0019781A2 successfully refreshed from Google Patents.
EP0019781A2
Expired / Lapsed
EP
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Method to produce a metal thin film pattern
Assignee: International Business Machines Corp
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Filing: 1980-05-09
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Granted: —
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Expires: 2000-05-09
Abstract
Abstract On a substrate blanket coatings of a metal thin film (5) and an organic polymer (6) are auccessively deposited. A pattern of openings (10) is formed through polymer (6). A blanket layer of matter (11) is deposited in the presence of which thin film (5) and polymer (6) are removable selectively. Polymer (6) is dissolved where the layers thereon are lifted off. The exposed portions of thin film (5) are removed. <??>Owing to being protected by metal thin film (5) during the lift-off process the substrate is not contaminated in the application of the method especially if dry-etching is used. <??>The method is employed effectively in semiconductor processing and can be used to fabricate Schottky barrier diodes and/or the metallization for integrated circuits on silicon wafers (1) containing semiconductor devices.
Inventors
- 👤 Laura Beth Rothman
- 👤 Paul Anthony Totta
- 👤 James Francis White
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 11:29
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/061; H10D64/00; H10D64/01; H10D64/011; H10D62/00; H10D62/80; H10D62/83; H10D64/0111; H10P; H10P76/00; H10P76/20; H10P76/202; H10W; H10W20/00; H10W20/40; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948; Y10S438/951
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
118 words
Method for forming a patterned metal thin film on a substrate by means of a lift-off process, characterized by a) depositing a blanket coating of a metal thin film (5) on the substrate b) depositing a blanket film of an organic polymer (6) on the metal thin film (5) c) forming a predetermined pattern of openings (10) through the polymer (6), thereby exposing portions of the metal thin film (5) d) depositing a blanket layer of matter (11) in the presence of which the polymer (6) and the metal thin film (5) are removable selectively e) disolving the polymer (6) and lifting off all superimposed layers thereon, and f) removing the exposed portions of metal thin film (5).
Claim 2
Dependent Claim
118 words
Method for forming a patterned metal thin film on a substrate by means of a lift-off process, characterized by a) depositing a blanket coating of a metal thin film (5) on the substrate b) depositing a blanket film of an organic polymer (6) on the metal thin film (5) c) forming a predetermined pattern of openings (10) through the polymer (6), thereby exposing portions of the metal thin film (5) d) depositing a blanket layer of matter (11) in the presence of which the polymer (6) and the metal thin film (5) are removable selectively e) disolving the polymer (6) and lifting off all superimposed layers thereon, and f) removing the exposed portions of metal thin film (5).
Claim 3
Dependent Claim
51 words
Method according to claim 1 characterized in that prior to step c) in claim 1 a blanket layer of a masking material (7) removable selectively in the presence of polymer (6) is deposited on polymer (6), and that the pattern of predetermined openings (10) is also formed through masking material (7).
Claim 4
Dependent Claim
62 words
Method according to claim 1 or 2 characterized in that an oxidized monocrystalline silicon body (1) having at least one semiconductor device formed therein and having at least one via hole (4) in the oxide film (2) is used as substrate, and that the pattern is predetermined in such a way that openings (9) are in register with corresponding via holes (4).
Claim 5
Dependent Claim
20 words
Method according to one or several of claims 1 to 3, characterized in that polysulfone is used as polymer (6).
Claim 6
Dependent Claim
22 words
Method according to one or several of claims 1 to 4, characterized in that silicon monoxide is used as masking material (7).
Claim 7
Dependent Claim
28 words
Method according to one or several of claims 1 to 5, characterized in that matter (11) is made of a composite of two layers consisting of different materials.
Claim 8
Dependent Claim
34 words
Method according to one or several of claims 1 to 6, characterized in that matter (11) is made of a second metal being in contact with the metal thin film (5) and/or of MgO.
Claim 9
Dependent Claim
38 words
Method according to one or several of claims 1 to 7, characterized in that the exposed portions of metal thin film (5) are removed by dry etching with non- lifted off matter (11) serving as dry etching mask.
Claim 10
Dependent Claim
67 words
Method according to one or several of claims 1 to 8, characterized in that a pattern of openings (9) is formed lithographically and the pattern of openings (10) corresponding to openings (9) is produced by reactive ion etching where the SiO - in case there is masking material (7) - is etched in CF 4 , and the polysulfone in 0 2 to which SiO is resistant.
Claim 11
Dependent Claim
30 words
Method according to one or several of claims 1 to 9, characterized in that a metal forming a Schottky barrier with silicon is used for the metal thin film (5).
Claim 12
Dependent Claim
20 words
Method according to claim 7, characterized in that a metal forming ohmic contacts with silicon is used as second metal.
Claim 13
Dependent Claim
33 words
Method according to one or several of claims 1 to 11, characterized in that after step e) of claim 1, steps d) and c) of claim 1 are repeated once or several times.
References Cited (Backward Citations)
No citation records indexed.
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