US4849854A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device and method of manufacturing the same
Assignee: Mitsubishi Electric Corp
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Filing: 1987-11-12
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Granted: 1989-07-18
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Expires: 2007-11-12
Abstract
Abstract Two or three trenches are formed in a silicon substrate, and a conductive layer is formed in the silicon substrate facing the trenches. An oxide film for insulation is formed on a surface of the conductive layer facing the trenches. The trenches are filled with polysilicon, and the conductive layer and the polysilicon constitute a capacitor through the oxide film. Since this capacitor has two or three trenches, an effective area sufficiently large for increasing a capacitance value of the capacitor can be obtained without increasing the plane area of the device. The conductive layer and the polysilicon are connected to aluminum interconnection layers through a silicide layer, so as to be connected to other integrated circuits.
Inventors
- 👤 Koji Eguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:59
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/01; H10D1/045; H10D1/047; H10B; H10B12/00; H10B12/30; H10B12/37; H10D1/60; H10D1/62; H10D1/66; H10D1/665; H10D1/68
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
80 words
A trench type capacitance element for integrated circuit, comprising: a semiconductor substrate having a major surface, a plurality of closely adjacent trenches extending into said substrate from said major surface thereof, an upper wall interconnecting immediately adjacent ones of said trenches being located deeper in said substrate than an upper end portion of an outermost one of said trenches, and a conductive material filling said trenches and a region between said upper wall and said major surfaces of said substrate.
Claim 2
Dependent Claim
80 words
A trench type capacitance element for integrated circuit, comprising: a semiconductor substrate having a major surface, a plurality of closely adjacent trenches extending into said substrate from said major surface thereof, an upper wall interconnecting immediately adjacent ones of said trenches being located deeper in said substrate than an upper end portion of an outermost one of said trenches, and a conductive material filling said trenches and a region between said upper wall and said major surfaces of said substrate.
Claim 3
Dependent Claim
19 words
A trench type capacitance element for integrated circuit in accordance with claim 1, wherein said conductive material comprises polysilicon.
Claim 4
Dependent Claim
24 words
A trench type capacitance element for integrated circuit in accordance with claim 1, including an insulating layer on a surface of each said trench.
Claim 5
Dependent Claim
25 words
A trench type capacitance element for integrated circuit in accordance with claim 3, wherein said insulating layer extends along said upper wall interconnecting said trenches.
Claim 6
Dependent Claim
21 words
A trench type capacitance element for integrated circuit in accordance with claim 4, wherein said insulating layer comprises SiO 2 .
Claim 7
Dependent Claim
21 words
A trench type capacitance element for integrated circuit in accordance with claim 3, wherein said insulating layer comprises SiO 2 .
Claim 8
Dependent Claim
27 words
A trench type capacitance element for integrated circuit in accordance with claim 3, including a conductive layer formed contiguous to said insulating layer in said semiconductor substrate.
Claim 9
Dependent Claim
26 words
A trench type capacitance element for integrated circuit in accordance with claim 7, wherein said conductive layer comprises a region of said substrate facing said trenches.
Claim 10
Dependent Claim
22 words
A trench type capacitance element for integrated circuit in accordance with claim 7, wherein said conductive layer is doped with an impurity.
Claim 11
Dependent Claim
29 words
A trench type capacitance element for integrated circuit in accordance with claim 7, including an electrode connected to said conductive material and an electrode connected to said conductive layer.
Claim 12
Dependent Claim
21 words
A trench type capacitance element for integrated circuit in accordance with claim 10, wherein said electrodes each comprise a silicide layer.
Claim 13
Dependent Claim
27 words
A trench type capacitance element for integrated circuit in accordance with claim 11, wherein said silicide layer is formed of any of TiSi, WSi, PtSi and MoSi.
Claim 14
Dependent Claim
23 words
A trench type capacitance element in accordance with claim 1, wherein said plurality of closely adjacent trenches have different depths in said substrate.
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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) | 1992-07-17 | 1993-01-16 | 1993-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-17 | 1997-01-16 | 1997-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-17 | 2001-01-16 | 2001-07-18 | $7700.00 | Window Closed / Lapsed |