US4415372A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making transistors by ion implantations, electron beam irradiation and thermal annealing
Assignee: Toshiba Corp
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Filing: 1981-10-20
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Granted: 1983-11-15
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Expires: 2001-10-20
Abstract
Abstract The invention provides a method for fabricating a semiconductor device which comprises the steps of ion-implanting an impurity into a monocrystalline semiconductor substrate; irradiating the region into which the impurity ions have been implanted with an accelerated electron beam under the conditions that the acceleration voltage is 20 to 200 KeV, and the current is 0.01 to 1 mA and the exposure dose is 10 20 to 10 15 /cm 2 ; and carrying out annealing to form a semiconductor region of one conductivity type. According to the present invention, a semiconductor device can be fabricated which has fewer lattice defects and in which the lifetime of the carriers is long.
Inventors
- 👤 Yutaka Koshino
- 👤 Toshio Yonezawa
- 👤 Takashi Ajima
- 👤 Jiro Ohshima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:57
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/21; H10P30/202; H10P30/204; H10P30/28; H10P95/00; H10P95/90; Y; Y10; Y10S; Y10S148/00; Y10S148/046
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
80 words
A method for fabricating a semiconductor device comprising the steps of: ion-implanting an impurity into a monocrystalline semiconductor substrate; irradiating a region into which said impurity ions have been implanted with an accelerated electron beam under the conditions that an acceleration voltage is 20 to 200 KeV, a current is 0.01 to 1 mA and an exposure dose is 10 12 to 10 15 /cm 2 ; and carrying out annealing to form a semiconductor region of one conductivity type.
Claim 2
Independent Claim
80 words
A method for fabricating a semiconductor device comprising the steps of: ion-implanting an impurity into a monocrystalline semiconductor substrate; irradiating a region into which said impurity ions have been implanted with an accelerated electron beam under the conditions that an acceleration voltage is 20 to 200 KeV, a current is 0.01 to 1 mA and an exposure dose is 10 12 to 10 15 /cm 2 ; and carrying out annealing to form a semiconductor region of one conductivity type.
Claim 3
Dependent Claim
11 words
A method according to claim 1, wherein said semiconductor is silicon.
Claim 4
Dependent Claim
11 words
A method according to claim 1, wherein said semiconductor is germanium.
Claim 5
Dependent Claim
21 words
A method according to claim 1, wherein said annealing is a thermal annealing with a temperature of 1,000° C. or more.
Claim 6
Dependent Claim
19 words
A method according to claim 1, wherein said irradiation conditions comprise an irradiation time of ten minutes or more.
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) | 1986-11-14 | 1987-05-16 | 1987-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-14 | 1991-05-16 | 1991-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-14 | 1995-05-16 | 1995-11-15 | $7700.00 | Window Closed / Lapsed |