US5382816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device having vertical transistor with tubular double-gate
Assignee: Renesas Electronics Corp
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Filing: 1993-05-28
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Granted: 1995-01-17
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Expires: 2013-05-28
Abstract
Abstract A semiconductor device allowing control of its threshold voltage without requiring change in the materials of its gate electrodes and suitable for high density integration is disclosed. The semiconductor device includes a p type monocrystalline silicon substrate 1 having a cylindrical portion with inner and outer surfaces and extending in a vertical direction. A first gate electrode 8 and a second gate electrode 10 are disposed at the inner surface and the outer surface of the cylindrical portion 2, respectively. A source/drain region 5 is formed on the top end of the cylindrical portion 2, while a source/drain region 3 is formed on the inner bottom surface of the cylindrical portion 2. Therefore, the cylindrical portion 2 can be utilized as a channel region of an MIS field effect transistor. The threshold voltage of the transistor can easily be controlled by applying separate voltages to the two gate electrodes, the first electrode and the second electrode.
Inventors
- 👤 Katsuyoshi Mitsui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:37
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/611; H10B; H10B12/00; H10B12/30; H10B12/39; H10B12/395; H10D30/01; H10D30/021; H10D30/025; H10D30/601; H10D30/608; H10D30/63; H10D64/00; H10D64/20; H10D64/27; H10D64/311; H10D64/411; H10D64/511; H10D64/512; H10D64/513
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
118 words
A semiconductor device, comprising: a semiconductor substrate of first type conductivity having a standing wall portion with inner and outer surfaces and extending in a tubular manner; a first tubular gate electrode formed on the inner surface of said standing wall portion with a first gate insulating film therebetween; a second tubular gate electrode formed on the outer surface of said standing wall portion with a second gate insulating film therebetween; a first source/drain region of second type conductivity formed on the top end of said standing wall portion; and a second source/drain region of the second type conductivity formed on the bottom surface of said semiconductor substrate surrounded by the inner surface of said standing wall portion.
Claim 2
Dependent Claim
118 words
A semiconductor device, comprising: a semiconductor substrate of first type conductivity having a standing wall portion with inner and outer surfaces and extending in a tubular manner; a first tubular gate electrode formed on the inner surface of said standing wall portion with a first gate insulating film therebetween; a second tubular gate electrode formed on the outer surface of said standing wall portion with a second gate insulating film therebetween; a first source/drain region of second type conductivity formed on the top end of said standing wall portion; and a second source/drain region of the second type conductivity formed on the bottom surface of said semiconductor substrate surrounded by the inner surface of said standing wall portion.
Claim 3
Dependent Claim
55 words
A semiconductor device as recited in claim 1, wherein said standing wall portion is cylindrical and extends from a prescribed region on a main surface of said semiconductor substrate in a direction approximately vertical to the main surface of said semiconductor substrate, said first gate electrode is cylindrical, and said second gate electrode is cylindrical.
Claim 4
Dependent Claim
58 words
A semiconductor device as recited in claim 1, wherein said first gate electrode is electrically connected to a first conductive layer, said second gate electrode is electrically connected to a second conductive layer, said first source/drain region is electrically connected to a third conductive layer, and said second source/drain region is electrically connected to a fourth conductive layer.
Claim 5
Dependent Claim
28 words
A semiconductor device as recited in claim 1, wherein said first gate electrode is a main gate electrode, and said second gate electrode is a sub gate electrode.
Claim 6
Dependent Claim
48 words
A semiconductor device as recited in claim 1, wherein an impurity region of the first type conductivity for fixing the potential of the substrate and isolating elements is formed on the main surface of said semiconductor substrate of the first type conductivity positioned outside said standing wall portion.
Claim 7
Dependent Claim
18 words
A semiconductor device as recited in claim 1, wherein said standing wall portion is formed of monocrystalline silicon.
Claim 8
Dependent Claim
143 words
A semiconductor device, comprising: a semiconductor substrate of first type conductivity having a standing wall portion with inner and outer surfaces and extending in a tubular manner; a first gate electrode formed on the inner surface of said standing wall portion with a first gate insulating film therebetween; a second gate electrode formed on the outer surface of said standing wall portion with a second gate insulating film therebetween; a first source/drain region of second type conductivity formed on the top end of said standing wall portion; a second source/drain region of the second type conductivity formed on the bottom surface of said semiconductor substrate surrounded by said inner surface of said standing wall portion; a capacitor lower electrode electrically connected to said second source/drain region; and a capacitor upper electrode formed on said capacitor lower electrode with a capacitor insulating film therebetween.
Claim 9
Dependent Claim
143 words
A semiconductor device, comprising: a semiconductor substrate of first type conductivity having a standing wall portion with inner and outer surfaces and extending in a tubular manner; a first gate electrode formed on the inner surface of said standing wall portion with a first gate insulating film therebetween; a second gate electrode formed on the outer surface of said standing wall portion with a second gate insulating film therebetween; a first source/drain region of second type conductivity formed on the top end of said standing wall portion; a second source/drain region of the second type conductivity formed on the bottom surface of said semiconductor substrate surrounded by said inner surface of said standing wall portion; a capacitor lower electrode electrically connected to said second source/drain region; and a capacitor upper electrode formed on said capacitor lower electrode with a capacitor insulating film therebetween.
Claim 10
Dependent Claim
43 words
A semiconductor device as recited in claim 7, wherein said standing wall portion is cylindrical and extends in a direction approximately vertical to a main surface of said semiconductor substrate, said first gate electrode is cylindrical, and said second gate electrode is cylindrical.
Claim 11
Dependent Claim
32 words
A semiconductor device as recited in claim 7, wherein said capacitor lower electrode is formed in a tubular manner in a direction approximately vertical to the main surface of said semiconductor substrate.
Claim 12
Dependent Claim
58 words
A semiconductor device as recited in claim 7, wherein said first gate electrode is electrically connected to a first conductive layer, said second gate electrode is electrically connected to a second conductive layer, said capacitor upper electrode is electrically connected to a third conductive layer, and said first source/drain region is electrically connected to a fourth conductive layer.
Claim 13
Dependent Claim
28 words
A semiconductor device as recited in claim 7, wherein said first gate electrode is a main gate electrode, and said second gate electrode is a sub gate electrode.
Claim 14
Dependent Claim
52 words
A semiconductor device as recited in claim 7, wherein an impurity region of the first type conductivity for fixing the potential of the substrate and isolating elements is formed in a prescribed region positioned outside said standing wall portion on the main surface of said semiconductor substrate of the first type conductivity.
Claim 15
Dependent Claim
25 words
A semiconductor device as recited in claim 12, wherein said impurity region of the first type conductivity is electrically connected to a fifth conductive layer.
Claim 16
Dependent Claim
18 words
A semiconductor device as recited in claim 7, wherein said standing wall portion is formed of mononocrystalline silicon.
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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) | 1998-01-16 | 1998-07-18 | 1999-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-16 | 2002-07-18 | 2003-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-16 | 2006-07-18 | 2007-01-17 | $7700.00 | Window Closed / Lapsed |