US5611955A
Expired / Lapsed
US
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High resistivity silicon carbide substrates for high power microwave devices
Assignee: Northrop Grumman Systems Corp
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Filing: 1993-10-18
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Granted: 1997-03-18
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Expires: 2013-10-18
Abstract
Abstract A substrate for use in semiconductor devices, fabricated of silicon carbide and having a resistivity of greater than 1500 Ohm-cm. The substrate being characterized as having deep level impurities incorporated therein, wherein the deep level elemental impurity comprises one of a selected heavy metal, hydrogen, chlorine and fluorine. The selected heavy metal being a metal found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.
Inventors
- 👤 Donovan L. Barrett
- 👤 Hudson M. Hobgood
- 👤 James P. McHugh
- 👤 Richard H. Hopkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:07
CPC Classifications
C; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/36; H; H10; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3408; H10P14/3438; H10P14/3441; H10P14/3446; Y; Y10; Y10S; Y10S148/00; Y10S148/148
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
76 words
A composition of matter for use in semiconductor devices, fabricated of single polytype silicon carbide and having a resistivity of at least 1500Ω-cm, the matter being characterized as having deep level dopants incorporated therein; wherein the deep level dopants are at a depth at least about 300 meV and include a selected heavy metal; and wherein the selected heavy metal is an element found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.
Claim 2
Dependent Claim
76 words
A composition of matter for use in semiconductor devices, fabricated of single polytype silicon carbide and having a resistivity of at least 1500Ω-cm, the matter being characterized as having deep level dopants incorporated therein; wherein the deep level dopants are at a depth at least about 300 meV and include a selected heavy metal; and wherein the selected heavy metal is an element found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.
Claim 3
Dependent Claim
22 words
The substrate of claim 1 wherein the deep level dopants are at least one of an element: and a combination of elements.
Claim 4
Dependent Claim
12 words
The substrate of claim 1 wherein the selected heavy metal is vanadium.
Claim 5
Dependent Claim
17 words
The matter of claim 1 wherein the dopant is incorporated during sublimation growth of the silicon carbide.
Claim 6
Dependent Claim
18 words
The matter of claim 1 wherein the dopant is incorporated during chemical vapor deposition of the silicon carbide.
Claim 7
Dependent Claim
18 words
The matter of claim 1 wherein the silicon carbide polytype is one of 2H, 4H, 6H and 15R.
Claim 8
Dependent Claim
47 words
A composition of matter for use in semiconductor devices, fabricated from a single polytype of silicon carbide including deep level vanadium at a depth at least about 300 meV and having a resisivity of at least 1500Ω-cm, wherein the vanadium is between 300 and 1000 ppm wt.
Claim 9
Dependent Claim
47 words
A composition of matter for use in semiconductor devices, fabricated from a single polytype of silicon carbide including deep level vanadium at a depth at least about 300 meV and having a resisivity of at least 1500Ω-cm, wherein the vanadium is between 300 and 1000 ppm wt.
Claim 10
Dependent Claim
52 words
A composition of matter for use in semiconductor devices, fabricated of single polytype silicon carbide and having a resistivity of at least 1500Ω-cm, the matter being characterized as having deep level dopants incorporated therein, wherein the deep level dopants are at a depth of at least 300 meV and act as compensators.
Claim 11
Dependent Claim
52 words
A composition of matter for use in semiconductor devices, fabricated of single polytype silicon carbide and having a resistivity of at least 1500Ω-cm, the matter being characterized as having deep level dopants incorporated therein, wherein the deep level dopants are at a depth of at least 300 meV and act as compensators.
Claim 12
Dependent Claim
17 words
The matter of claim 8 wherein the dopant is incorporated during sublimation growth of the silicon carbide.
Claim 13
Dependent Claim
18 words
The matter of claim 8 wherein the dopant is incorporated during chemical vapor deposition of the silicon carbide.
Claim 14
Dependent Claim
18 words
The matter of claim 8 wherein the silicon carbide polytype is one of 2H, 4H, 6H and 15R.
Claim 15
Dependent Claim
56 words
A composition of matter for use in semiconductor devices comprised of a silicon carbide semiconductor material having deep level dopants at a depth of at least 300 meV and a resistivity of at least 5×10 4 Ω-cm, wherein the dopants include an element found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.
Claim 16
Dependent Claim
56 words
A composition of matter for use in semiconductor devices comprised of a silicon carbide semiconductor material having deep level dopants at a depth of at least 300 meV and a resistivity of at least 5×10 4 Ω-cm, wherein the dopants include an element found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.
Claim 17
Dependent Claim
15 words
The composition of matter in claim 12 wherein the silicon carbide semiconductor material is semi-insulating.
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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) | 2000-03-17 | 2000-09-16 | 2001-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-17 | 2004-09-16 | 2005-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-17 | 2008-09-16 | 2009-03-18 | $7700.00 | Window Closed / Lapsed |