US5142350A
Expired / Lapsed
US
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Transistor having cubic boron nitride layer
Assignee: Delphi Technologies Inc
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Filing: 1990-07-16
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Granted: 1992-08-25
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Expires: 2010-07-16
Abstract
Abstract A multilayer structure for use in forming a transistor which may be suitable for high temperature applications is provided. A single crystal silicon substrate has an overlaying layer of epitaxially grown cubic boron nitride in crystallographic registry with the silicon substrate. The cubic boron nitride is epitaxially grown using laser ablation techniques and provides an electrically resistive and thermally conductive barrier. An active layer of epitaxial silicon is then grown from the layer of cubic boron nitride, such that the overlaying layer of epitaxial silicon is in crystallographic registry with the layer of boron nitride which is in crystallographic registry with the underlying silicon substrate. Appropriately doped source and drain regions and a gate electrode are provided to form the transistor. A clean crystallographic lattice match between the cubic boron nitride and surrounding silicon is obtained, thereby minimizing any stresses due to a mismatch in lattice constants and permitting the overlaying silicon active layer to be extremely thin.
Inventors
- 👤 Joseph P. Heremans
- 👤 Gary L. Doll
- 👤 Jeffrey A. Sell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:26
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6744; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; H10D30/0323; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/2926; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3216; H10P14/3258; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3466; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10W; H10W10/00; H10W10/10; H10W10/181
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
116 words
A transistor comprising: a silicon substrate crystallographically oriented along a single crystallographic plane; an overlaying layer of cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; a layer of silicon overlaying said layer of cubic boron nitride, said layer of silicon having a crystallographic lattice substantially matching that of said layer of cubic boron nitride; appropriately doped source and drain regions within said silicon layer, said source and drain regions are spaced such that an undoped region of said silicon layer is provided between said source and drain regions; and a gate electrode essentially overlaying said silicon layer at said undoped region, so as to contact said source and drain regions.
Claim 2
Dependent Claim
116 words
A transistor comprising: a silicon substrate crystallographically oriented along a single crystallographic plane; an overlaying layer of cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; a layer of silicon overlaying said layer of cubic boron nitride, said layer of silicon having a crystallographic lattice substantially matching that of said layer of cubic boron nitride; appropriately doped source and drain regions within said silicon layer, said source and drain regions are spaced such that an undoped region of said silicon layer is provided between said source and drain regions; and a gate electrode essentially overlaying said silicon layer at said undoped region, so as to contact said source and drain regions.
Claim 3
Dependent Claim
19 words
A transistor as recited in claim 1 wherein said silicon substrate is crystallographically oriented along the [100] crystallographic plane.
Claim 4
Dependent Claim
41 words
A transistor as set forth in claim 1 wherein said silicon substrate and silicon layer each have a lattice constant of about 5.43 Angstroms so as to accommodate three cubic boron nitride lattices with a lattice mismatch of less than 0.05%.
Claim 5
Dependent Claim
123 words
A transistor comprising: an essentially single crystal silicon substrate crystallographically oriented along the [100] crystallographic plane; an overlaying layer of epitaxial cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; a layer of epitaxial silicon overlaying said layer of cubic boron nitride, said layer of epitaxial silicon having a crystallographic lattice substantially matching that of said layer of cubic boron nitride; appropriately doped source and drain regions within said epitaxial silicon layer, said source and drain regions are spaced such that an undoped region of said silicon layer is provided between said source and drain regions; and a gate electrode essentially overlaying said silicon layer at said undoped region so as to contact said source and drain regions.
Claim 6
Dependent Claim
123 words
A transistor comprising: an essentially single crystal silicon substrate crystallographically oriented along the [100] crystallographic plane; an overlaying layer of epitaxial cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; a layer of epitaxial silicon overlaying said layer of cubic boron nitride, said layer of epitaxial silicon having a crystallographic lattice substantially matching that of said layer of cubic boron nitride; appropriately doped source and drain regions within said epitaxial silicon layer, said source and drain regions are spaced such that an undoped region of said silicon layer is provided between said source and drain regions; and a gate electrode essentially overlaying said silicon layer at said undoped region so as to contact said source and drain regions.
Claim 7
Dependent Claim
61 words
A multilayer structure comprising: a silicon substrate oriented essentially along a single crystallographic plane; an overlaying layer of cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; and a layer of silicon overlaying said layer of cubic boron nitride, said layer of silicon having a crystallographic lattice substantially matching that of said layer of boron nitride.
Claim 8
Dependent Claim
61 words
A multilayer structure comprising: a silicon substrate oriented essentially along a single crystallographic plane; an overlaying layer of cubic boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; and a layer of silicon overlaying said layer of cubic boron nitride, said layer of silicon having a crystallographic lattice substantially matching that of said layer of boron nitride.
Claim 9
Dependent Claim
20 words
A multilayer structure as recited in claim 5 wherein said silicon substrate is oriented essentially along the [100] crystallograpic plane.
Claim 10
Dependent Claim
62 words
A multilayer structure comprising: an essentially single crystal silicon substrate oriented essentially along the [100] crystallographic plane; an overlaying of epitaxial boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; and a layer of epitaxial silicon overlaying said layer of epitaxial cubic boron nitride having a crystallographic lattice substantially matching that of said layer of cubic boron nitride.
Claim 11
Dependent Claim
62 words
A multilayer structure comprising: an essentially single crystal silicon substrate oriented essentially along the [100] crystallographic plane; an overlaying of epitaxial boron nitride having a crystallographic lattice substantially matching that of said silicon substrate; and a layer of epitaxial silicon overlaying said layer of epitaxial cubic boron nitride having a crystallographic lattice substantially matching that of said layer of cubic boron nitride.
Claim 12
Dependent Claim
42 words
A multilayer structure as set forth in claim 7 wherein said silicon substrate and silicon layer each have a lattice constant of about 5.43 Angstroms so as to accommodate three cubic boron nitride lattices with a lattice mismatch of less than 0.05%.
References Cited (Backward Citations)
US3877060A
Cited
US4177474A
Cited
JPS57122515A
Cited
JPS59114853A
Cited
JPS61149477A
Cited
JPS61222111A
Cited
US4772927A
Cited
US4809056A
Cited
JPS63120429A
Cited
JPS63129631A
Cited
US4914491A
Cited
US4906587A
Cited
US4950618A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-25 | 1996-02-24 | 1996-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-25 | 2000-02-24 | 2000-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-25 | 2004-02-24 | 2004-08-25 | $7700.00 | Window Closed / Lapsed |