Patent US4448632A successfully refreshed from Google Patents.
US4448632A
Expired / Lapsed
US
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Method of fabricating semiconductor devices
Assignee: Mitsubishi Electric Corp
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Filing: 1982-05-21
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Granted: 1984-05-15
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Expires: 2002-05-21
Abstract
Abstract A method of manufacturing a semiconductor device utilizing a monocrystalline silicon layer includes forming and irradiating a polycrystalline silicon layer to increase the grain size thereof, and forming an epitaxial layer thereover. Both layers are then irradiated to convert them into high quality monocrystalline silicon.
Inventors
- 👤 Yoichi Akasaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:05
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/24; H10P14/2921; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/38; H10P14/3802; H10P14/3808; H10P14/3814; H10P34/00; H10P34/40; H10P34/42; H10P95/00; H10P95/90; Y; Y10; Y10S; Y10S117/00; Y10S117/903; Y10S117/904; Y10S117/913; Y10S148/00; Y10S148/09; Y10S148/093
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
105 words
A method of fabricating semiconductor devices, comprising the steps of forming a polycrystalline silicon layer on an insulating or amorphous layer; irradiating said polycrystalline silicon layer with a laser or electron beam so as to increase the grain size of said polycrystalline silicon layer and to provide a plurality of monocrystals in the polycrystalline layer; epitaxially forming a layer primarily containing silicon on said altered polycrystalline silicon layer; and melting said epitaxially grown layer and said polycrystalline silicon layer with an irradiation of a laser or electron beam so as to obtain a monocrystalline layer from said epitaxially grown layer and said polycrystalline silicon layer.
Claim 2
Independent Claim
105 words
A method of fabricating semiconductor devices, comprising the steps of forming a polycrystalline silicon layer on an insulating or amorphous layer; irradiating said polycrystalline silicon layer with a laser or electron beam so as to increase the grain size of said polycrystalline silicon layer and to provide a plurality of monocrystals in the polycrystalline layer; epitaxially forming a layer primarily containing silicon on said altered polycrystalline silicon layer; and melting said epitaxially grown layer and said polycrystalline silicon layer with an irradiation of a laser or electron beam so as to obtain a monocrystalline layer from said epitaxially grown layer and said polycrystalline silicon layer.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1, including forming a grating on the upper surface of said insulating or amorphous layer on which said polycrystalline silicon layer is formed.
Claim 4
Independent Claim
17 words
A method as claimed in claims 1, or 2, wherein said insulating layer is of silicon oxide.
Claim 5
Dependent Claim
24 words
A method as claimed in claim 3, wherein the thickness of said silicon oxide layer is in a range from 1 to 2 μm.
Claim 6
Independent Claim
17 words
A method as claimed in claims 1 or 2, wherein said insulating layer is of silicon nitride.
Claim 7
Dependent Claim
24 words
A method as claimed in claim 1, wherein the thickness of said polycrystalline silicon layer is in a range from 0.1 to 0.3 μm.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 1, wherein said epitaxially grown layer is formed in a SiH 2 Cl 2 atmosphere under a reduced pressure.
Claim 9
Dependent Claim
24 words
A method as claimed in claim 1, wherein the thickness of said epitaxially grown layer is in a range from 0.5 to 1.0 μm.
Claim 10
Independent Claim
143 words
A method of fabricating a semiconductor device, comprising the steps of forming a polycrystalline silicon layer on an insulating or amorphous layer; irradiating said polycrystalline silicon layer with a laser or electron beam so as to increase the grain size of said polycrystalline silicon layer and to provide a plurality of monocrystal in the polycrystalline layer; epitaxially forming a layer primarily containing silicon on said altered polycrystalline silicon layer; partially oxidizing said epitaxially grown layer to form an oxide layer spreading through said polycrystalline silicon layer to said insulating or amorphous layer to thereby electrically separate a non-oxidized portion of said epitaxially grown layer from the remaining portions thereof; and melting said non-oxidized portion of said epitaxially grown layer and said polycrystalline silicon layer beneath said non-oxidized portion with a laser or electron beam to monocrystalline said epitaxially grown and polycrystalline silicon layers.
Claim 11
Independent Claim
143 words
A method of fabricating a semiconductor device, comprising the steps of forming a polycrystalline silicon layer on an insulating or amorphous layer; irradiating said polycrystalline silicon layer with a laser or electron beam so as to increase the grain size of said polycrystalline silicon layer and to provide a plurality of monocrystal in the polycrystalline layer; epitaxially forming a layer primarily containing silicon on said altered polycrystalline silicon layer; partially oxidizing said epitaxially grown layer to form an oxide layer spreading through said polycrystalline silicon layer to said insulating or amorphous layer to thereby electrically separate a non-oxidized portion of said epitaxially grown layer from the remaining portions thereof; and melting said non-oxidized portion of said epitaxially grown layer and said polycrystalline silicon layer beneath said non-oxidized portion with a laser or electron beam to monocrystalline said epitaxially grown and polycrystalline silicon layers.
Claim 12
Dependent Claim
29 words
A method as claimed in claim 9, including forming a grating on the upper surface of said insulating or amorphous layer on which said polycrystalline silicon layer is formed.
Claim 13
Independent Claim
17 words
A method as claimed in claims 9 or 10, wherein said insulating layer is of silicon oxide.
Claim 14
Dependent Claim
24 words
A method as claimed in claim 11, wherein the thickness of said silicon oxide layer is in a range from 1 to 2 μm.
Claim 15
Independent Claim
17 words
A method as claimed in claims 9 or 10, wherein said insulating layer is of silicon nitride.
Claim 16
Dependent Claim
24 words
A method as claimed in claim 9, wherein the thickness of said polycrystalline silicon layer is in a range from 0.1 to 0.3 μm.
Claim 17
Dependent Claim
25 words
A method as claimed in claim 9, wherein said epitaxially grown layer is formed in a SiH 2 Cl 2 atmosphere under a reduced pressure.
Claim 18
Independent Claim
26 words
A method as claimed in claims 9 or 15, wherein the thickness of said epitaxially grown layer is in a range from 0.5 to 1.0 μm.
References Cited (Backward Citations)
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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) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |