EP0137645A2
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EP
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Method of forming a shallow N-type region
Assignee: Fujitsu Ltd
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Filing: 1984-08-14
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Granted: —
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Expires: 2004-08-14
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 (15) containing arsenic or antimony on a silicon substrate (11): forming a second film (18) containing phosphorus on the first film (15); and diffusing the arsenic or antimony and the phosphorus into the semi-conductor substrate (11) 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 (21) and the arsenic or antimony defines the depth of the n-type region (21).
Inventors
- 👤 Katsunobu Ueno
- 👤 Osamu Hataishi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 20:12
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: 6
Claim 1
Independent Claim
100 words
A method of forming a shallow n-type region (21) of a semiconductor device by introducing n-type impurities into a silicon semiconductor substrate (11), characterised by the steps of forming a first film (15) containing arsenic or antimony on the silicon substrate; forming a second film (18) containing phosphorus on the first film (15); and diffusing the arsenic or antimony and the phosphorus into the semiconductor substrate out of the first and second films (15,18) by heat-treatment, the arrangement being such that the diffusion depth of the arsenic or antimony is equal to or exceeds the diffusion depth of the phosphorus.
Claim 2
Independent Claim
100 words
A method of forming a shallow n-type region (21) of a semiconductor device by introducing n-type impurities into a silicon semiconductor substrate (11), characterised by the steps of forming a first film (15) containing arsenic or antimony on the silicon substrate; forming a second film (18) containing phosphorus on the first film (15); and diffusing the arsenic or antimony and the phosphorus into the semiconductor substrate out of the first and second films (15,18) by heat-treatment, the arrangement being such that the diffusion depth of the arsenic or antimony is equal to or exceeds the diffusion depth of the phosphorus.
Claim 3
Dependent Claim
32 words
A method according to claim 1, characterised in that the first film (15) and the second film (18) are made of polycrystalline silicon, amorphous silicon, or a silicide of platinum or tungsten.
Claim 4
Dependent Claim
39 words
A method according to claim 1 or claim 2, characterised in that arsenic or antimony is doped into the first film (15) by an ion-implantation method and phosphorus is doped into the second film (18) by an ion-implantation method.
Claim 5
Dependent Claim
51 words
A method according to claim 1 or claim 2, characterised in that arsenic or antimony is doped into the first film (15) during the formation thereof by a chemical vapour deposition method and phosphorus is doped into the second film (18) during the formation thereof by a chemical vapour deposition method.
Claim 6
Independent Claim
53 words
A method according to any of claims 1 to 3, wherein arsenic or antimony is doped into the first film (15) after the first film has been formed on the silicon substrate, and phosphorus is doped into the second film (18) after the second film has been formed on the first film (15).
References Cited (Backward Citations)
No citation records indexed.
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