Patent US4372990A successfully refreshed from Google Patents.
US4372990A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Retaining wall technique to maintain physical shape of material during transient radiation annealing
Assignee: Texas Instruments Inc
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Filing: 1980-06-23
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Granted: 1983-02-08
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Expires: 2000-06-23
Abstract
Abstract A method for preparing semiconductor material for integrated circuit device fabrication. A retaining wall is formed around islands of semiconductor material that are to include the active devices, and the islands are then subjected to transient radiation annealing. The retaining wall holds the shape of the islands during annealing, and promotes uniform crystal alignment in the material.
Inventors
- 👤 Hon W. Lam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:46
CPC Classifications
H; H10; H10P; H10P34/00; H10P34/40; H10P34/42
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
79 words
A method for preparing small islands of semiconductor material for device fabrication, comprising the steps of: depositing a layer of polysilicon on a first insulating layer which is on a substrate; masking areas of said polysilicon layer, to become islands, with a second insulating material; subjecting the exposed surface of said polysilicon layer to an oxidation process; removing said second insulator material from the upper surface of said silicon islands; and subjecting said silicon islands to transient radiation annealing.
Claim 2
Independent Claim
79 words
A method for preparing small islands of semiconductor material for device fabrication, comprising the steps of: depositing a layer of polysilicon on a first insulating layer which is on a substrate; masking areas of said polysilicon layer, to become islands, with a second insulating material; subjecting the exposed surface of said polysilicon layer to an oxidation process; removing said second insulator material from the upper surface of said silicon islands; and subjecting said silicon islands to transient radiation annealing.
Claim 3
Independent Claim
100 words
A method for preparing small islands of semiconductor material for device fabrication, comprising the steps of; depositing small islands of polysilicon on a first insulating layer which is on a substrate; depositing a second insulating layer over said islands and said first layer of insulating material; subjecting said second layer of insulating material to an anisotropic plasma etch process for removal said of said second layer of insulator from the top surface of said islands while leaving walls of said second layer insulator adjacent to vertical surface of said islands; and subjecting said islands of polysilicon to transient radiation annealing.
Claim 4
Independent Claim
100 words
A method for preparing small islands of semiconductor material for device fabrication, comprising the steps of; depositing small islands of polysilicon on a first insulating layer which is on a substrate; depositing a second insulating layer over said islands and said first layer of insulating material; subjecting said second layer of insulating material to an anisotropic plasma etch process for removal said of said second layer of insulator from the top surface of said islands while leaving walls of said second layer insulator adjacent to vertical surface of said islands; and subjecting said islands of polysilicon to transient radiation annealing.
Claim 5
Dependent Claim
16 words
A method as in claim 1 wherein said transient radiation is provided by a laser beam.
Claim 6
Dependent Claim
16 words
A method as in claim 2 wherein said transient radiation is provided by a laser beam.
Claim 7
Dependent Claim
15 words
A method as in claim 1 wherein said first insulating layer is SiO 2 .
Claim 8
Dependent Claim
17 words
A method as in claim 1 wherein said second insulating material is Si 3 N 4 .
Claim 9
Dependent Claim
15 words
A method as in claim 2 wherein said first insulating layer is SiO 2 .
Claim 10
Dependent Claim
17 words
A method as in claim 2 wherein said second insulator layer is Si 3 N 4 .
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) | 1986-02-07 | 1986-08-09 | 1987-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-07 | 1990-08-09 | 1991-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-07 | 1994-08-09 | 1995-02-08 | $7700.00 | Window Closed / Lapsed |