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US3698077A
Expired / Lapsed
US
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Method of producing a planar-transistor
Assignee: Telefunken Electronic GmbH
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Filing: 1969-11-25
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Granted: 1972-10-17
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Expires: 1989-11-25
Abstract
Abstract A method of producing a planar transistor by forming a window in a passivating layer on a semiconductor body, diffusing into the semiconductor body through this window an emitter region and a base region in either order, forming a second window adjacent the first window and diffusing a base contact region there through to a depth such as to make contact with the base region. Electrodes are then provided in the first window for the emitter region and in the second window for the base region. Either window may be formed first depending on the diffusing arrangements.
Inventors
- 👤 Reinhard Dahlberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:29
CPC Classifications
H; H10; H10P; H10P95/00; H10P14/00; H10P14/40; H10P14/46; H10W; H10W20/00; H10W20/40
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
87 words
A method of producing a planar transistor comprising forming a passivation layer on a semiconductor body, forming a first window in said passivation layer, diffusing a base contact region into said semiconductor body through said first window, subsequently forming a second window adjacent said first window, and, while said first window is open, diffusing through said second window a base region and an emitter region into said semiconductor body, the diffusing of said base region bringing said base region into electrical contact with said base contact region.
Claim 2
Independent Claim
87 words
A method of producing a planar transistor comprising forming a passivation layer on a semiconductor body, forming a first window in said passivation layer, diffusing a base contact region into said semiconductor body through said first window, subsequently forming a second window adjacent said first window, and, while said first window is open, diffusing through said second window a base region and an emitter region into said semiconductor body, the diffusing of said base region bringing said base region into electrical contact with said base contact region.
Claim 3
Dependent Claim
71 words
A method as defined in claim 1, wherein said base contact region is indiffused with a surface concentration high enough to prevent said base contact region from changing its conductivity type under counter-doping by the emitter diffusion impurities penetrating into said first window during the emitter diffusion, and high enough to prevent its conductivity from dropping below the value necessary for a connection between the base region and a base electrode.
Claim 4
Dependent Claim
23 words
A method as defined in claim 2, wherein said base contact region is diffused deeper into the semiconductor body than said base region.
Claim 5
Dependent Claim
46 words
A method as defined in claim 1, wherein said first and second windows are separated by a web of the material of the passivation layer having a width less than the sum of the penetration depths of the base region And of the base contact region.
Claim 6
Dependent Claim
25 words
A method as defined in claim 1, wherein said first window is formed as an annulus and said second window is formed within said annulus.
Claim 7
Dependent Claim
20 words
A method as defined in claim 1, wherein said first and second windows are formed with an interengaging comb-like structure.
Claim 8
Dependent Claim
51 words
A method as defined in claim 1 further comprising making-non rectifying contact with said emitter region and said base contact region by electrodes and thereafter removing the entire passivation layer, replacing said passivating layer by a fresh passivation layer applied pyrolytically and removing said passivating layer again only over the electrodes.
Claim 9
Dependent Claim
53 words
A method as defined in claim 1 further comprising making non-rectifying contact with said emitter region and said base contact region by electrodes and thereafter removing the entire passivation layer, replacing said passivating layer by a fresh passivation layer applied through cathode sputtering and removing said passivating layer again only over the electrodes.
Claim 10
Dependent Claim
16 words
A method as defined in claim 1, wherein said passivation layer is formed of silicon oxide.
Claim 11
Dependent Claim
16 words
A method as defined in claim 1, wherein said passivation layer is formed of silicon nitride.
Claim 12
Dependent Claim
18 words
A method as defined in claim 1 wherein said diffused regions are formed by means of powder diffusion.
Claim 13
Dependent Claim
30 words
A method as defined in claim 1, wherein contact is made to the collector region of said transistor at the surface of the semiconductor body opposite to said emitter region.
Claim 14
Dependent Claim
31 words
A method as claimed in claim 1, including making non-rectifying contact to said emitter region and said base contact region by means of an electrolytic deposition, without electrodes, of metal layers.
Claim 15
Dependent Claim
23 words
A method as defined in claim 13, wherein the metal of said metal layers consists of gold, platinum metals, silver, nickel or copper.
Claim 16
Dependent Claim
19 words
A method as defined in claim 1, wherein said semiconductor body consists of silicon, germanium or an AIIIBV compound.
Claim 17
Dependent Claim
30 words
A method as defined in claim 1, further comprising contacting said base region through said base contact region in said first window and said emitter region through said second window.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |