Patent US3661727A successfully refreshed from Google Patents.
US3661727A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing semiconductor devices
Assignee: Hitachi Ltd
•
Filing: 1970-01-29
•
Granted: 1972-05-09
•
Expires: 1990-01-29
Abstract
Abstract The method of plating a metal layer on a selected, clean surface of a semiconductor substrate with a metal provides for forming at first a layer of silicon dioxide on the substrate surface by the high temperature oxidation method, then forming a hollow on one part thereof, thereafter immersing the semiconductor substrate in a mixture of an etching solution and a metal-plating solution for a limited period of time sufficient for only a part of the silicon dioxide film positioning on this hollow part to dissolve and to expose a clean surface of the substrate and sufficient for a metal layer of a certain thickness to be metal-plated on the clean surface.
Inventors
- 👤 Yokichi Itoh
- 👤 Nobuhiko Shirasaka
- 👤 Shoji Tauchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:40
CPC Classifications
H; H10; H10P; H10P95/00; C; C25; C25D; C25D7/00; C25D7/12; H10P14/00; H10P14/40; H10P14/46; H10P14/47; H10W; H10W74/00; H10W74/40; H10W74/43
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
A method for producing semiconductor devices having metal-to-semiconductor contacts comprising the steps of: providing on a semiconductor body a single layer of an electrically insulating film having a relatively thin hollow part therein; and immersing said semiconductor body with said film into a mixture of a metal-plating solution and an etching solution containing a solvent capable of dissolving the insulating film, for a period of time, during which said insulating film is dissolved to such an extent as to expose a surface portion of the semiconductor body at said hollow part only and the metal in the metal-plating solution is plated on said exposed surface of the semiconductor body, thereby to obtain a metal-to-semiconductor contact, and withdrawing said semiconductor body from said mixture prior to the dissolving of the remaining part of said film.
Claim 2
Independent Claim
128 words
A method for producing semiconductor devices having metal-to-semiconductor contacts comprising the steps of: providing an electrically insulating film on a surface of a semiconductor body; reducing the thickness of said insulating film at a predetermined portion thereof to form a hollow part thereon; and immersing said semiconductor body in a metal-plating solution containing metal to be plated and a solvent capable of dissolving said insulating film, for a period of time, during which said solvent dissolves said insulating film to such an extent as to expose the surface of the semiconductor body underlying the hollow part and the metal contained in the solution is electroplated on the surface of the semiconductor body so exposed, thereby to obtain a metal-to-semiconductor contact without dissolving the remaining part of said film.
Claim 3
Dependent Claim
31 words
A method according to claim 3, in which said step of reducing the thickness of the insulating film comprises the step of photoetching the insulating film at the preselected portion thereof.
Claim 4
Dependent Claim
16 words
A method according to claim 3, in which said insulating film is formed by evaporative deposition.
Claim 5
Independent Claim
152 words
A method for producing semiconductor devices which comprises the steps of: coating the exterior surface of a semiconductor body with an electrically insulating film; forming in said insulating film at a specific portion on said body at least one hollow part of relatively thinner thickness than the thickness of the remaining part of the insulating film other than said hollow part; covering the entire surface of said insulating film with a liquid having a property capable of dissolving said insulating film until only said hollow part of said film is completely dissolved so as to expose a surface portion of said body underneath the hollow part to the liquid; and then immersing into a metal-plating sOlution said semiconductor body whose surface is covered by said liquid without contacting the thus exposed surface portion of said semiconductor body to air so as to carry out metal-plating only on said surface portion so exposed.
Claim 6
Dependent Claim
29 words
A method according to claim 6, wherein said semiconductor body is silicon and said insulating film is silicon oxide formed through thermal oxidation of the semiconductor body in steam.
Claim 7
Independent Claim
113 words
A method for producing semiconductor devices having metal-to-semiconductor contacts comprising the steps of: preparing a semiconductor body covered with an electrically insulating film; reducing the thickness of said film at a predetermined region of said body; covering the resulting predetermined region of reduced thickness of the insulating film by a liquid capable of dissolving said insulating film until the liquid completely dissolves the film in said predetermined region; and then immersing in a metal-plating solution said semiconductor body covered by said liquid without causing the semiconductor surface at said predetermined region to be exposed to air until a metal layer is formed through plating on said surface of the semiconductor body so exposed.
Claim 8
Dependent Claim
32 words
A method according to claim 8, wherein said semiconductor body is silicon and said insulating film is silicon oxide formed through thermal oxidation of the surface of the semiconductor body in steam.
References Cited (Backward Citations)
CA701897A
Cited
US2802159A
Cited
US2885608A
Cited
US2814589A
Cited
US3081418A
Cited
US2861931A
Cited
US2958633A
Cited
US3096259A
Cited
US2995473A
Cited
US3075892A
Cited
US3160534A
Cited
US3171762A
Cited
US3234058A
Cited
US3226611A
Cited
US3237271A
Cited
US3272748A
Cited
US3388000A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |