US3577045A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High emitter efficiency simiconductor device with low base resistance and by selective diffusion of base impurities
Assignee: General Electric Co
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Filing: 1968-09-18
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Granted: 1971-05-04
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Expires: 1988-09-18
Abstract
Abstract A transistor, such as NPN type, for example, is fabricated by first diffusing a heavily doped P-type base contact region into an N-type semiconductor layer epitaxially grown on a heavily doped N-type semiconductor wafer. Holes are etched through the base contact region into the N-type layer and strongly N-type semiconductor material containing both N-type impurities and faster diffusing P-type impurities is epitaxially grown so as to fill the holes. The wafer is then heated to diffuse the P-type impurities so as to form a base region of controlled thickness, simultaneously forming emitter-base and base-collector junctions. Emitter contact is made by contacting the material epitaxially grown in the holes. Other type semiconductor devices, such as semiconductor controlled rectifiers, may also be fabricated in this manner.
Inventors
- 👤 William E Engeler
- 👤 Marvin Garfinkel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:45
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/13; H10D62/133; H10D99/00; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3438; H10P14/3441; H10P95/00; Y; Y10; Y10S; Y10S148/00; Y10S148/043; Y10S148/05; Y10S148/151
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
34 words
The improved transistor of claim 1 wherein the concentration of impurities producing said one type conductivity in said emItter region exceeds the concentration of impurities producing said one type conductivity in said collector region.
Claim 2
Dependent Claim
29 words
The improved transistor of claim 1 wherein said emitter region extends beyond the interface of said collector and base contact regions, said base region being of substantially constant thickness.
Claim 3
Dependent Claim
19 words
The improved transistor of claim 1 wherein the ratio of emitter thickness to base thickness is greater than 3.
Claim 4
Dependent Claim
25 words
The improved transistor of claim 1 wherein said base region contains impurities comprising the same chemical element as said impurities in said base contact region.
Claim 5
Dependent Claim
48 words
The improved transistor of claim 1 wherein said semiconductor comprises silicon, said impurities producing the one type conductivity comprising one of the group consisting of phosphorous, arsenic and antimony, and said impurities producing the opposite type conductivity comprising one of the group consisting of boron, gallium and aluminum.
Claim 6
Dependent Claim
47 words
The improved transistor of claim 1 wherein said semiconductor comprises silicon, said impurities producing the one type conductivity comprising one of the group consisting of boron and gallium, and said impurities producing the opposite type conductivity comprising one of the group consisting of phosphorous, antimony and arsenic.
Claim 7
Dependent Claim
29 words
The improved transistor of claim 1 wherein said base region contains impurities comprising a first chemical element and said base contact region contains impurities comprising a second chemical element.
Claim 8
Dependent Claim
177 words
An improved semiconductor junction transistor comprising: a collector region doped with impurities to produce one type conductivity; a base contact region of opposite type conductivity adjacent a major surface of said collector region; a plurality of emitter regions, each of said emitter regions being spaced apart from each other and extending through said base contact region, each of said emitter regions being substantially uniformly doped throughout its extent predominantly with a concentration of impurities producing said one type conductivity and also containing impurities of the opposite conductivity determining type at a lower concentration; a plurality of base regions of said opposite-type conductivity, each of said base regions being situated respectively between one of said emitter regions and said collector region and merging with said base contact region, each of said base regions containing at its respective interface with an emitter region a lower concentration of impurities of the opposite conductivity determining type than said base contact region; first conductive means contacting at least one of said emitter regions; and additional conductive means contacting said base contact region.
Claim 9
Dependent Claim
34 words
The improved transistor of claim 9 wherein the concentration of impurities producing said one type conductivity in said emitter regions exceeds the concentration of impurities producing said one type conductivity in said collector region.
Claim 10
Dependent Claim
33 words
The improved transistor of claim 9 wherein each of said emitter regions extends beyond the interface of said collector and base contact regions, each of said base regions being of substantially constant thickness.
Claim 11
Dependent Claim
16 words
The improved transistor of claim 9 wherein said first conductive means conjointly contacts said emitter regions.
Claim 12
Dependent Claim
34 words
The improved transistor of claim 9 including electrical insulator means disposed atop said base contact region and containing an aperture therein through which said additional conductive means makes contact with said base contact region.
Claim 13
Dependent Claim
34 words
The improved transistor of claim 12 including electrical insulator means disposed atop said base contact region and containing an aperture therein through which said additional conductive means makes contact with said base contact region.
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) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |