Patent US4724189A successfully refreshed from Google Patents.
Patent US4025411A successfully refreshed from Google Patents.
US4025411A
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US
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Fabricating semiconductor device utilizing a physical ion etching process
Assignee: Hitachi Ltd
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Filing: 1975-10-28
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Granted: 1977-05-24
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Expires: 1995-10-28
Abstract
Abstract An even surface of an SiO2 layer on an Si body, whose surface is uneven, is obtained by the steps of forming a photoresist layer of KTFR (Trade name of Eastman Kodak Chemical Company) on the uneven surface of the SiO2 layer so as to have a thickness sufficient cover the unevenness of the surface and etching the SiO2 layer with said KTFR layer by rf sputter etching so as to expose a predetermined surface of the SiO2 layer.
Inventors
- 👤 Yoshio Hom-Ma
- 👤 Tadao Kaji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:29
CPC Classifications
H; H10; H10P; H10P95/00; H10P50/00; H10P50/20; H10P95/06; H10P95/062; H10P95/064; H10W; H10W74/00; H10W74/01; H10P14/00; H10P14/60; H10P14/68; H10P14/683; Y; Y10; Y10S; Y10S148/00; Y10S148/02; Y10S148/105
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
110 words
A method for fabricating a semiconductor device comprising the steps of: applying a layer of liquid material to an uneven surface of a substrate to a thickness sufficient to form an even-surfaced layer covering the uneven surface of said substrate; converting said layer of liquid material to a layer of solid material which has about the same etching rate with respect to a physical etching utilizing ions as the material composing the surface of said substrate; and etching said layer of solid material and the surface of said substrate covered thereby with said physical etching utilizing ions, so as to expose a predetermined portion of the surface of said substrate.
Claim 2
Independent Claim
110 words
A method for fabricating a semiconductor device comprising the steps of: applying a layer of liquid material to an uneven surface of a substrate to a thickness sufficient to form an even-surfaced layer covering the uneven surface of said substrate; converting said layer of liquid material to a layer of solid material which has about the same etching rate with respect to a physical etching utilizing ions as the material composing the surface of said substrate; and etching said layer of solid material and the surface of said substrate covered thereby with said physical etching utilizing ions, so as to expose a predetermined portion of the surface of said substrate.
Claim 3
Dependent Claim
39 words
A method for fabricating a semiconductor device according to claim 1, wherein said substrate surface consists of a material selected from the group consisting of Si, SiO 2 , phospho-silicate glass, boro-silicate glass, Si 3 N 4 and aluminum.
Claim 4
Dependent Claim
21 words
A method for fabricating a semiconductor device according to claim 2, wherein said substrate surface consists of a material of Si.
Claim 5
Dependent Claim
38 words
A method for fabricating a semiconductor device according to claim 2, wherein said substrate surface consists of a material selected from the group consisting of SiO 2 , Si 3 N 4 , phospho-silicate glass and boro-silicate glass.
Claim 6
Dependent Claim
21 words
A method for fabricating a semiconductor device according to claim 2, wherein said substrate surface consists of a material of aluminum.
Claim 7
Dependent Claim
51 words
A method for fabricating a semiconductor device according to claim 2, wherein said layer consists of a material selected from the group consisting of negative-type photoresists, positive-type photoresists, positive-type resists for electron beams, negative-type resists for electron beams, polyimide resin, polyimide-iso-indroquinazolinedione and low temperature fusible glass being able to be coated.
Claim 8
Dependent Claim
57 words
A method for fabricating a semiconductor device according to claim 6, wherein said positive-type resists for electron beams are selected from the group consisting of poly(methyl methacrylate) and poly(butene-1 sulfon), and wherein said negative-type resists for electron beams are selected from the group consisting of epoxidized polybutadiene, copolymer of glycidyl methacrylate and ethyl acrylate, and poly(glycidyl methacrylate).
Claim 9
Dependent Claim
44 words
A method for fabricating a semiconductor device according to claim 3, wherein said layer consists of a material selected from the group consisting of negative-type photoresists, positive-type photoresists, poly(methyl methacrylate), poly(butene-1 sulfon), epoxidized polybutadiene, copolymer of glycidyl methacrylate and ethyl acrylate, and poly(glycidyl methacrylate).
Claim 10
Dependent Claim
30 words
A method for fabricating a semiconductor device according to claim 4, wherein said layer consists of a material selected from the group consisting of negative-type photoresists, polyimide resin and polyimide-iso-indroquinazolinedione.
Claim 11
Dependent Claim
43 words
A method for fabricating a semiconductor device according to claim 5, wherein said layer consists of a material selected from the group consisting of positive-type photoresists, poly(methyl methacrylate), poly(butene-1 sulfon), epoxidized polybutadiene, copolymer of glycidyl methacrylate and ethyl acrylate, and poly (glycidyl methacrylate).
Claim 12
Dependent Claim
29 words
A method for fabricating a semiconductor device according to claim 1, wherein said physical etching is selected from the group consisting of a sputter etching and an ion milling.
Claim 13
Dependent Claim
75 words
A method for fabricating a semiconductor device according to claim 11, wherein said physical etching is an rf sputter etching wherein conditions are an rf power of 0.1- 10 W/cm 2 , a sheath potential of lower than 2000 V, Ar pressure of 5 × 10.sup. -2 - 1 × 10.sup. -4 Torr., an oxygen concentration of lower than 0.1%, and a substrate temperature of lower than melting temperature of the material of said layer.
Claim 14
Dependent Claim
46 words
A method for fabricating a semiconductor device according to claim 12, wherein said rf power is between 0.1 W/cm 2 and 5 W/cm 2 , said sheath potential is between 700 V and 1500 V, and said substrate temperature is between 100° C. and 200° C.
Claim 15
Dependent Claim
69 words
A method for fabricating a semiconductor device according to claim 11, wherein said physical etching is an ion milling wherein conditions are an ion energy of 20 eV- 90 KeV, a degree of vacuum of 1 × 10.sup. -3 - 5 × 10.sup. -6 Torr., a current density of 0.5- 5 mA/cm 2 , and a substrate temperature of lower than melting temperature of the material of said layer.
Claim 16
Dependent Claim
33 words
A method for fabricating a semiconductor device according to claim 14, wherein said ion energy is between 20 eV and 30 Kev, and said substrate temperature is between 100° C. and 200° C.
Claim 17
Dependent Claim
22 words
A method for fabricating a semiconductor device according to claim 15, wherein said ion energy is between 3 Kev and 10 Kev.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-23 | 1980-11-22 | 1981-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-23 | 1984-11-22 | 1985-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-23 | 1988-11-22 | 1989-05-24 | $7700.00 | Window Closed / Lapsed |