Patent US4897710A successfully refreshed from Google Patents.
US4897710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device
Assignee: Sharp Corp
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Filing: 1987-08-18
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Granted: 1990-01-30
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Expires: 2007-08-18
Abstract
Abstract The semiconductor device comprises a silicon substrate, a boron-doped high resistant silicon carbide layer that is formed on the silicon substrate and a silicon carbide layer formed on the high resistant silicon carbide layer. The silicon carbide layer that is formed on the high resistant silicon carbide layer provides an electrical insulation for the device so that improved device characteristics are obtained.
Inventors
- 👤 Akira Suzuki
- 👤 Katsuki Furukawa
- 👤 Akitsugu Hatano
- 👤 Atsuko Uemoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:42
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/83; H10D62/832; H10D62/8325; H10D1/00; H10D1/60; H10D1/68; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; H10W70/698
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
129 words
A structure for a p-n junction gate type FET semiconductor device, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming an active layer of the semiconductor device, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer; a third silicon carbide layer disposed on a first portion of said second silicon carbide layer for forming a channel layer; a first electrode layer disposed on a second portion of said second silicon carbide layer for forming a source electrode and a drain electrode; and a second electrode layer disposed on said third silicon carbide layer for forming a gate electrode.
Claim 2
Dependent Claim
129 words
A structure for a p-n junction gate type FET semiconductor device, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming an active layer of the semiconductor device, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer; a third silicon carbide layer disposed on a first portion of said second silicon carbide layer for forming a channel layer; a first electrode layer disposed on a second portion of said second silicon carbide layer for forming a source electrode and a drain electrode; and a second electrode layer disposed on said third silicon carbide layer for forming a gate electrode.
Claim 3
Dependent Claim
24 words
A structure as set forth in claim 1, wherein said second silicon carbide layer is formed of a non-doped n-type single crystal silicon layer.
Claim 4
Dependent Claim
23 words
A structure as set forth in claim 1, wherein said third silicon carbide layer is formed of a p-type single crystal silicon layer.
Claim 5
Dependent Claim
17 words
A structure as set forth in claim 1, wherein said first electrode layer is formed of Ni.
Claim 6
Dependent Claim
18 words
A structure as set forth in claim 1, wherein said second electrode is formed of an aluminum-silicon alloy.
Claim 7
Dependent Claim
99 words
A structure for a semiconductor resistor, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming a resistive layer of the semiconductor resistor, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer and said second silicon carbide layer is formed of a nitrogen doped-type single crystal silicon layer; and an electrode layer disposed on said second silicon carbide layer for forming a pair of ohmic electrodes for the resistor.
Claim 8
Dependent Claim
99 words
A structure for a semiconductor resistor, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming a resistive layer of the semiconductor resistor, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer and said second silicon carbide layer is formed of a nitrogen doped-type single crystal silicon layer; and an electrode layer disposed on said second silicon carbide layer for forming a pair of ohmic electrodes for the resistor.
Claim 9
Dependent Claim
27 words
A structure as set forth in claim 6, wherein an amount of nitrogen doped in said second silicon carbide layer determines a resistivity value of the resistor.
Claim 10
Dependent Claim
132 words
A structure for a semiconductor capacitor, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming a bottom plate layer of the semiconductor capacitor, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer; a dielectric layer disposed on a first portion of said second silicon carbide layer for forming a capacitance layer; a first electrode layer disposed on a second portion of said second silicon carbide layer for forming a first electrode contacted to said second silicon carbide layer, thereby forming a bottom plate; and a second electrode layer disposed on said dielectric layer for forming a top plate of the capacitor.
Claim 11
Dependent Claim
132 words
A structure for a semiconductor capacitor, comprising: a substrate; a first silicon carbide layer disposed on said substrate for electrically insulating said substrate; a second silicon carbide layer disposed on said first silicon carbide layer for forming a bottom plate layer of the semiconductor capacitor, wherein said second silicon carbide layer is electrically insulated from said substrate by said first silicon carbide layer; a dielectric layer disposed on a first portion of said second silicon carbide layer for forming a capacitance layer; a first electrode layer disposed on a second portion of said second silicon carbide layer for forming a first electrode contacted to said second silicon carbide layer, thereby forming a bottom plate; and a second electrode layer disposed on said dielectric layer for forming a top plate of the capacitor.
Claim 12
Dependent Claim
23 words
A structure as set forth in claim 8, wherein said second silicon carbide layer is formed of an n-type single crystal silicon layer.
Claim 13
Dependent Claim
25 words
A structure as set forth in claim 9, wherein said n-type single crystal silicon layer has a second predetermined resistivity less than 0.1 ohm cm.
Claim 14
Dependent Claim
18 words
A structure as set forth in claim 10, wherein said n-type single crystal silicon layer is nitrogen doped.
Claim 15
Dependent Claim
18 words
A structure as set forth in claim 8, wherein said dielectric layer is formed of an oxide layer.
Claim 16
Dependent Claim
16 words
A structure as set forth in claim 8, wherein said first electrode is formed of Ni.
Claim 17
Dependent Claim
16 words
A structure as set forth in claim 8, wherein said second electrode is formed of Al.
References Cited (Backward Citations)
US3497773A
Cited
US3716844A
Cited
US4071945A
Cited
US4224636A
Cited
US4177474A
Cited
US4109271A
Cited
US4329699A
Cited
US4385200A
Cited
US4531142A
Cited
US4536459A
Cited
US4633287A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |