US5143858A
Expired / Lapsed
US
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Method of fabricating buried insulating layers
Assignee: NXP USA Inc
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Filing: 1990-04-02
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Granted: 1992-09-01
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Expires: 2010-04-02
Abstract
Abstract A thick buried insulating layer is formed by employing a multiple semiconductor layer growth/implant/anneal cycle. A first buried insulating layer is formed in a semiconductor substrate by implanting a dopant which reacts with the substrate to form an insulating layer and then annealing the substrate. Subsequently, a thin semiconductor layer is grown on the surface of the substrate. This is followed by a second implantation of the dopant which reacts with the substrate to form an insulating layer and an anneal to form a second buried insulating layer. The two buried insulating layers may be continuous to form a single, thick buried insulating layer or may be discontinuous to form two buried insulating layers separated by a semiconductor layer. The cycle may be repeated until a desirable thickness of the buried insulating layer is achieved or until a desirable number of buried insulating layers are formed.
Inventors
- 👤 Mamoru Tomozane
- 👤 H. Ming Liaw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:25
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/208; H10P30/209
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
131 words
A method of fabricating a buried insulating layer, comprising the steps of: providing a semiconductor substrate; implanting a first dopant which reacts to form an insulating layer to a predetermined depth in the semiconductor substrate; annealing the semiconductor substrate to form a first buried insulating layer in the semiconductor substrate, wherein a portion of the semiconductor substrate above the buried insulating layer is called a superficial semiconductor layer; forming a semiconductor layer on the superficial semiconductor layer; implanting a second dopant which reacts to form an insulating layer into the superficial semiconductor layer and the semiconductor layer; and annealing the semiconductor substrate to form a second buried insulating layer, wherein the first buried insulating layer and the second buried insulating layer are separated by a portion of the superficial semiconductor layer.
Claim 2
Independent Claim
131 words
A method of fabricating a buried insulating layer, comprising the steps of: providing a semiconductor substrate; implanting a first dopant which reacts to form an insulating layer to a predetermined depth in the semiconductor substrate; annealing the semiconductor substrate to form a first buried insulating layer in the semiconductor substrate, wherein a portion of the semiconductor substrate above the buried insulating layer is called a superficial semiconductor layer; forming a semiconductor layer on the superficial semiconductor layer; implanting a second dopant which reacts to form an insulating layer into the superficial semiconductor layer and the semiconductor layer; and annealing the semiconductor substrate to form a second buried insulating layer, wherein the first buried insulating layer and the second buried insulating layer are separated by a portion of the superficial semiconductor layer.
Claim 3
Dependent Claim
41 words
The method of claim 1 further comprising repeating the steps of forming the semiconductor layer, implanting the second dopant which reacts to form an insulating layer, and annealing the semiconductor substrate until a desirable number of buried insulating layers are formed.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein the first buried insulating layer and the second buried insulating layer are comprised of different insulating materials.
Claim 5
Dependent Claim
23 words
The method of claim 1 wherein the first and the second dopants which react to form an insulating layer are comprised of oxygen.
Claim 6
Dependent Claim
28 words
The method of claim 4 wherein the oxygen is implanted at a dose approximately equal to 1.8×10 18 atoms/cm 2 and at an energy of approximately 200 keV.
Claim 7
Dependent Claim
23 words
The method of claim 1 wherein the first and the second dopants which react to form an insulating layer are comprised of nitrogen.
Claim 8
Independent Claim
113 words
A method of fabricating a buried insulating layer, comprising the steps of: providing a structure which is comprised of a semiconductor substrate, a first buried insulating layer on the semiconductor substrate, and a superficial semiconductor layer on the buried insulating layer; forming a semiconductor layer on the superficial semiconductor layer; implanting a dopant which reacts with the superficial semiconductor layer to form an insulating layer, such that the peak concentration of the dopant is positioned in the superficial semiconductor layer; and annealing the structure to form a second buried insulating layer, wherein the first buried insulating layer and the second buried insulating layer are separated by a portion of the superficial semiconductor layer.
Claim 9
Independent Claim
113 words
A method of fabricating a buried insulating layer, comprising the steps of: providing a structure which is comprised of a semiconductor substrate, a first buried insulating layer on the semiconductor substrate, and a superficial semiconductor layer on the buried insulating layer; forming a semiconductor layer on the superficial semiconductor layer; implanting a dopant which reacts with the superficial semiconductor layer to form an insulating layer, such that the peak concentration of the dopant is positioned in the superficial semiconductor layer; and annealing the structure to form a second buried insulating layer, wherein the first buried insulating layer and the second buried insulating layer are separated by a portion of the superficial semiconductor layer.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1995-09-01 | 1996-03-02 | 1996-09-01 | $2000.00 | Window Closed / Lapsed |
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