US4875085A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device with shallow n-type region with arsenic or antimony and phosphorus
Assignee: Fujitsu Ltd
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Filing: 1988-05-17
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Granted: 1989-10-17
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Expires: 2008-05-17
Abstract
Abstract A method of forming a shallow n-type region of a semiconductor device such as a bipolar transistor and a MOS FET, including the steps of: forming a first film containing arsenic or antimony on a silicon substrate; forming a second film containing phosphorus on the first film; and diffusing the arsenic or antimony and the phosphorus into the semiconductor substrate out of the first and second films by heat-treatment. The diffused impurities of the arsenic or antimony and the phosphorus form the n-type region and the arsenic or antimony defines the depth of the n-type region.
Inventors
- 👤 Katsunobu Ueno
- 👤 Osamu Hataishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:16
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/30; H10D48/32; H10D48/34; H10D48/345; H10P; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/1414; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
174 words
A semiconductor device, comprising: a single crystalline substrate; a p-type semiconductor epitaxial layer of single crystalline silicon formed on said single crystalline layer; an n-type region, formed in said p-type semiconductor epitaxial layer, comprising an upper subregion with phosphorous and at least one of arsenic and antiomony diffused therein and a lower subregion, below the upper subregion, with the at least one of arsenic and antimony and substantially no phosphorous diffused therein; an insulation film, formed on said p-type semiconductor epitaxial layer, having a window at said n-type region; a first polycrystalline silicon film, formed on said n-type region and at the window in said insulation film, including silicon, phosphorous and the at least one of arsenic and antimony; a second polycrystalline silicon film, formed on said first polycrystalline film, including silicon and phosphorous, said first and second films having identical predetermined patterns; and a metal layer formed on said second polycrystalline silicon film, whereby said first and second polycrystalline silicon films and said metal layer form a contact structure for said n-type region.
Claim 2
Dependent Claim
174 words
A semiconductor device, comprising: a single crystalline substrate; a p-type semiconductor epitaxial layer of single crystalline silicon formed on said single crystalline layer; an n-type region, formed in said p-type semiconductor epitaxial layer, comprising an upper subregion with phosphorous and at least one of arsenic and antiomony diffused therein and a lower subregion, below the upper subregion, with the at least one of arsenic and antimony and substantially no phosphorous diffused therein; an insulation film, formed on said p-type semiconductor epitaxial layer, having a window at said n-type region; a first polycrystalline silicon film, formed on said n-type region and at the window in said insulation film, including silicon, phosphorous and the at least one of arsenic and antimony; a second polycrystalline silicon film, formed on said first polycrystalline film, including silicon and phosphorous, said first and second films having identical predetermined patterns; and a metal layer formed on said second polycrystalline silicon film, whereby said first and second polycrystalline silicon films and said metal layer form a contact structure for said n-type region.
Claim 3
Dependent Claim
22 words
A semiconductor device as recited in claim 1, wherein said n-type region is a shallow n-type emitter region of a bipolar transistor.
Claim 4
Dependent Claim
275 words
A semiconductor device including a bipolar transistor, comprising: a single crystalline substrate; a n-type collector semiconductor epitaxial layer of single crystalline silicon formed on said single crystalline substrate; a p-type base region formed in a first portion of said n-type collector semiconductor epitaxial layer; a n-type emitter region, formed in said p-type base region in said n-type collector semiconductor epitaxial layer, comprising an upper subregion with phosphorous and at least one of arsenic and antimony diffused therein and a lower subregion, below the upper subregion, with at least one of arsenic and antimony and substantially no phosphorous diffused therein; an insulation film, formed on said n-type collector semiconductor epitaxial layer, the p-type base region and the n-type emitter region, having first, second and third windows at said n-type emitter region, at a portion of the p-type base region, and at a second portion of the n-type collector semiconductor epitaxial layer, respectively; a first polycrystalline silicon film, formed on said n-type emitter region and at the first window in said insulation film, including silicon, phosphorous and at least one of arsenic and antimony; a second polycrystalline silicon film, formed on said first polycrystalline film and including silicon and phosphorous, said first and second films having substantially identical, predetermined patterns; a metal layer formed on said second polycrystalline silicon film, whereby said first and second polycrystalline silicon films and said metal layer form a contact structure for said n-type emitter region; a base electrode formed on said p-type base region at the second window in said insulation film; and a collector electrode formed on said n-type collector semiconductor layer at the third window in said insulation film.
Claim 5
Dependent Claim
275 words
A semiconductor device including a bipolar transistor, comprising: a single crystalline substrate; a n-type collector semiconductor epitaxial layer of single crystalline silicon formed on said single crystalline substrate; a p-type base region formed in a first portion of said n-type collector semiconductor epitaxial layer; a n-type emitter region, formed in said p-type base region in said n-type collector semiconductor epitaxial layer, comprising an upper subregion with phosphorous and at least one of arsenic and antimony diffused therein and a lower subregion, below the upper subregion, with at least one of arsenic and antimony and substantially no phosphorous diffused therein; an insulation film, formed on said n-type collector semiconductor epitaxial layer, the p-type base region and the n-type emitter region, having first, second and third windows at said n-type emitter region, at a portion of the p-type base region, and at a second portion of the n-type collector semiconductor epitaxial layer, respectively; a first polycrystalline silicon film, formed on said n-type emitter region and at the first window in said insulation film, including silicon, phosphorous and at least one of arsenic and antimony; a second polycrystalline silicon film, formed on said first polycrystalline film and including silicon and phosphorous, said first and second films having substantially identical, predetermined patterns; a metal layer formed on said second polycrystalline silicon film, whereby said first and second polycrystalline silicon films and said metal layer form a contact structure for said n-type emitter region; a base electrode formed on said p-type base region at the second window in said insulation film; and a collector electrode formed on said n-type collector semiconductor layer at the third window in said insulation film.
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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) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |