Patent US4276368A successfully refreshed from Google Patents.
US4276368A
Expired / Lapsed
US
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Photoinduced migration of silver into chalcogenide layer
Assignee: Occidental Chemical Corp
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Filing: 1979-05-04
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Granted: 1981-06-30
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Expires: 1999-05-04
Abstract
Abstract Lithographic patterning of particular interest in fabrication of integrated circuitry is based on the photoinduced migration of silver into germanium selenide or other glassy material of appropriate absorption cross section for the chosen actinic radiation. Resists which are negative-acting yield high resolution attributed to initial introduction of the silver in chemically combined form chosen so as to result in formation of a silver compound with a glass component with the compound serving as silver source. Removal of excess silver-containing material is engineered on the basis of the form of silver introduction and results in conversion to a water soluble form. Commercial use will likely be based on an embodiment in which the now developed patterned resist serves as a dry etching mask during delineation of a relatively thick underlying layer of organic material. This procedure is particularly advantageous for use on partially processed circuitry in which prior operations have resulted in surface steps.
Inventors
- 👤 Adam Heller
- 👤 King L. Tai
- 👤 Richard G. Vadimsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:47
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/0042; G03F7/0044; H; H10; H10P; H10P14/00; H10P14/60
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
203 words
Process for fabrication of an article comprising an operation during which the article undergoing fabrication comprises an article surface and an overlying actinic processing layer, said processing layer consisting essentially of a chalcogenide glass and silver-containing material, the silver-containing material being largely concentrated to essentially uniform depth in the vicinity of a surface of the said layer, including the steps of (1) selectively exposing portions of the said processing layer to actinic radiation so as to induce migration of silver in a direction from the said surface into the body of said layer within such exposed portions thereby defining a pattern of material of reduced solubility in a developing agent; (2) stripping so as to remove silver-containing material unaffected by radiation; (3) treating the said processing layer with said developing agent to selectively remove material within unexposed portions to produce a now patterned processing layer, characterized in that silver-containing material consists essentially of at least one chemical compound consisting of the reaction product of combined silver and at least one component of the glassy material, and in that stripping comprises reaction resulting in a water-soluble silver compound which reaction may be regarded as comprising conversion of silver halide to said water-soluble silver compound.
Claim 2
Dependent Claim
203 words
Process for fabrication of an article comprising an operation during which the article undergoing fabrication comprises an article surface and an overlying actinic processing layer, said processing layer consisting essentially of a chalcogenide glass and silver-containing material, the silver-containing material being largely concentrated to essentially uniform depth in the vicinity of a surface of the said layer, including the steps of (1) selectively exposing portions of the said processing layer to actinic radiation so as to induce migration of silver in a direction from the said surface into the body of said layer within such exposed portions thereby defining a pattern of material of reduced solubility in a developing agent; (2) stripping so as to remove silver-containing material unaffected by radiation; (3) treating the said processing layer with said developing agent to selectively remove material within unexposed portions to produce a now patterned processing layer, characterized in that silver-containing material consists essentially of at least one chemical compound consisting of the reaction product of combined silver and at least one component of the glassy material, and in that stripping comprises reaction resulting in a water-soluble silver compound which reaction may be regarded as comprising conversion of silver halide to said water-soluble silver compound.
Claim 3
Dependent Claim
22 words
Process of claim 1 in which there is a sacrificial layer intermediate the said actinic processing layer and the said article surface.
Claim 4
Dependent Claim
52 words
Process of claim 2 in which the said sacrificial layer is processed so as to result in a replica pattern by exposing the article product resulting from processing in accordance with claim 1 to an agent which selectively attacks portions of the said sacrificial layer bared during patterning of the processing layer.
Claim 5
Dependent Claim
14 words
Process of claim 2 in which the said sacrificial layer is a polymeric material.
Claim 6
Dependent Claim
22 words
Process of claims 3 or 4 in which the said agent is a plasma-produced species resulting from discharge within an oxygen ambient.
Claim 7
Dependent Claim
20 words
Process of claim 5 in which the replica pattern in the said sacrificial layer is produced by reactive ion etching.
Claim 8
Dependent Claim
42 words
Process of claims 1, 3, or 4 in which the said article surface is patterned selectively within regions bared by the patterned processing layer by reaction with a fabrication agent, thereby resulting in a device-significant local alteration of the said article surface.
Claim 9
Dependent Claim
26 words
Process of claim 1 in which the said chalcogenide glass contains at least one chalcogen element selected from the group consisting of selenium, sulphur, and tellurium.
Claim 10
Dependent Claim
48 words
Process of claim 8 in which the amount of the said chalcogen element is in excess of the amount indicated by a stoichiometric compound formed with another constituent of the said glass and in which the said developing agent includes a solvent specific to the said chalcogen element.
Claim 11
Dependent Claim
13 words
Process of claim 9 in which the said excess chalcogen element is selenium.
Claim 12
Dependent Claim
25 words
Process of claim 10 in which the said specific solvent is selected from the group consisting of at least one compound sulfide and a borohydride.
Claim 13
Dependent Claim
41 words
Process of claim 1 in which the said silver-containing material is the reaction product of the said component of the glassy material together with a compound in which silver is included in anionic form as a part of a complex anion.
Claim 14
Dependent Claim
14 words
Process of claim 12 in which the said anion consists essentially of silver cyanide.
Claim 15
Dependent Claim
13 words
Process of claim 13 in which silver is introduced as KAg(CN) 2 .
Claim 16
Dependent Claim
35 words
Process of claim 1 in which stripping comprises reaction which may be regarded as conversion of silver halide to a water soluble silver compound by reaction of the said halide with an alkali metal cyanide.
Claim 17
Dependent Claim
33 words
Process of claim 1 in which stripping comprises reaction which may be regarded as conversion of silver halide to a water soluble silver compound by reaction of the said halide with a halide.
Claim 18
Dependent Claim
15 words
Process of claim 1 in which the said silver halide consists essentially of silver chloride.
Claim 19
Dependent Claim
35 words
Process of claim 1 in which the said silver containing material is a non-halide and in which stripping comprises reaction which may be regarded as comprising conversion of the said silver-containing material to silver halide.
Claim 20
Dependent Claim
37 words
Process of claim 18 in which stripping comprises reaction carried out in two chemically distinct steps, the first resulting in silver halide, the second resulting in conversion of the said halide to a water soluble silver compound.
Claim 21
Dependent Claim
26 words
Process of claim 18 in which stripping comprises reaction in of a single step which may be regarded as producing silver halide as an intermediate product.
Claim 22
Dependent Claim
28 words
Process of claim 20 in which the stripping reaction involves reaction between the said silver-containing material and a solution of an alkali metal halide together with elemental halogen.
Claim 23
Dependent Claim
14 words
Process of claim 21 in which the alkali metal halide consists of potassium halide.
Claim 24
Dependent Claim
23 words
Process of claim 22 in which the alkali metal halide consists of potassium iodide and in which the said halogen consists of iodine.
Claim 25
Dependent Claim
25 words
Process of claim 1 in which selectively exposed portions correspond with transparent portions of a mask interposed between the said article and actinic radiation source.
Claim 26
Dependent Claim
15 words
Process of claim 24 in which the said article surface contains combined or uncombined silicon.
Claim 27
Dependent Claim
25 words
Process of claim 1 in which selective exposure results from modulation of a beam of said radiation which moves relative to the said article surface.
References Cited (Backward Citations)
US3561963A
Cited
US3707372A
Cited
US3620795A
Cited
US3754913A
Cited
US3892571A
Cited
US4052211A
Cited
US4113486A
Cited
US4115127A
Cited
US4127414A
Cited
US4144066A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-29 | 1984-12-29 | 1985-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-29 | 1988-12-29 | 1989-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-29 | 1992-12-29 | 1993-06-30 | $7700.00 | Window Closed / Lapsed |