Patent US5189503A successfully refreshed from Google Patents.
US5189503A
Expired / Lapsed
US
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High dielectric capacitor having low current leakage
Assignee: Toshiba Corp
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Filing: 1991-04-10
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Granted: 1993-02-23
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Expires: 2011-04-10
Abstract
Abstract A dielectric insulation film consists of a metal oxide and pieces of dissimilar metal element added to the metal oxide. A positive charge number under an ionized state of the dissimilar metal element is smaller by one than that of the metal oxide. An ionic charge number of the dissimilar metal element is of a predetermined one kind. The dielectric insulation film is formed as an insulation film of capacitor of each cell of a semiconductor device according to a chemical vapor deposition (CVD) method in the process of forming cells of the semiconductor device.
Inventors
- 👤 Kyoichi Suguro
- 👤 Keitaro Imai
- 👤 Mitsutoshi Koyama
- 👤 Kikuo Yamabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:05
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10B; H10B12/00; H10B12/30; H10B12/31; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6329; H10P14/6334; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69392; H10P14/69393; H10P14/69394; H10P14/69395; H10P14/69396; H10P14/69397
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
148 words
A semiconductor device comprising: a lower electrode made of a simple substance of a metallic element and formed on a semiconductor substrate; a first insulation film formed on said lower electrode, said first insulation film composed of an oxide of a transition metal and pieces of a dissimilar metal element added to the oxide, the positive charge number under an ionized state of the dissimilar metal element being smaller by one than that of the transition metal, the dissimilar metal element having only a single valence to fix said positive charge number; an upper electrode formed on said first insulation film; and a second insulation film disposed between said first insulation film and said lower electrode or between said first insulation film and said upper electrode, said second insulation film being composed of a metal oxide having a dielectric constant higher than that of said first insulation film.
Claim 2
Dependent Claim
148 words
A semiconductor device comprising: a lower electrode made of a simple substance of a metallic element and formed on a semiconductor substrate; a first insulation film formed on said lower electrode, said first insulation film composed of an oxide of a transition metal and pieces of a dissimilar metal element added to the oxide, the positive charge number under an ionized state of the dissimilar metal element being smaller by one than that of the transition metal, the dissimilar metal element having only a single valence to fix said positive charge number; an upper electrode formed on said first insulation film; and a second insulation film disposed between said first insulation film and said lower electrode or between said first insulation film and said upper electrode, said second insulation film being composed of a metal oxide having a dielectric constant higher than that of said first insulation film.
Claim 3
Dependent Claim
30 words
The semiconductor device as claimed in claim 1, wherein the quantity of said added dissimilar metal element is less than five atomic percent of the metal in said metal oxide.
Claim 4
Dependent Claim
39 words
The semiconductor device as claimed in claim 1, wherein said metal oxide is one of Ta 2 O 5 and Nb 2 O 5 , and said added dissimilar metal element is at least one of Zr and Hf.
Claim 5
Dependent Claim
39 words
The semiconductor device as claimed in claim 1, wherein said metal oxide is one of ZrO 2 , HfO 2 and TiO 2 , and said added dissimilar metal element is at least one of Sc, Y and La.
Claim 6
Dependent Claim
46 words
The semiconductor device as claimed in claim 1, wherein said first insulation film is a Zr-added Ta 2 O 5 or Hf-added Ta 2 O 5 film, said upper and lower electrodes are made of W, and said second insulation film is a tungsten oxide film.
Claim 7
Dependent Claim
19 words
The semiconductor device as claimed in claim 5, wherein said tungsten oxide film is made from WO 2 .
Claim 8
Dependent Claim
21 words
The semiconductor device as claimed in claim 6, wherein said tungsten oxide film is made through oxidation of said lower electrode.
Claim 9
Dependent Claim
18 words
The semiconductor device as claimed in claim 1, wherein said second insulation film is a titanium oxide film.
Claim 10
Dependent Claim
34 words
The semiconductor device as claimed in claim 1, wherein the quantity of the added dissimilar metal element is less than five atomic percent of a transition metal which is composing said first insulation film.
Claim 11
Dependent Claim
80 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of niobium or tantalum on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween in order to form a capacitance, wherein said oxide material of niobium or tantalum is given an additive of zirconium or hafnium at no higher than 5 atomic %.
Claim 12
Dependent Claim
80 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of niobium or tantalum on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween in order to form a capacitance, wherein said oxide material of niobium or tantalum is given an additive of zirconium or hafnium at no higher than 5 atomic %.
Claim 13
Dependent Claim
82 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of zirconium, hafnium or titanium on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween in order to form a capacitance, wherein said oxide material of zirconium, hafnium or titanium is given an additive of scandium or yttrium at no higher than 5 atomic %.
Claim 14
Dependent Claim
82 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of zirconium, hafnium or titanium on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween in order to form a capacitance, wherein said oxide material of zirconium, hafnium or titanium is given an additive of scandium or yttrium at no higher than 5 atomic %.
Claim 15
Dependent Claim
86 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of zirconium, hafnium or titanium on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween to form a capacitance, wherein said oxide material of zirconium, hafnium or titanium has an additive of scandium or yttrium to suppress current leakage through said dielectric film between said upper and lower electrodes.
Claim 16
Dependent Claim
86 words
A semiconductor device comprising: a semiconductor substrate; a lower electrode formed on said substrate; a dielectric film made of an oxide material of zirconium, hafnium or titanium on said lower electrode; and an upper electrode formed on said dielectric film and insulated from said lower electrode through said dielectric film interposed therebetween to form a capacitance, wherein said oxide material of zirconium, hafnium or titanium has an additive of scandium or yttrium to suppress current leakage through said dielectric film between said upper and lower electrodes.
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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) | 1996-02-23 | 1996-08-24 | 1997-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-02-23 | 2000-08-24 | 2001-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-02-23 | 2004-08-24 | 2005-02-23 | $7700.00 | Window Closed / Lapsed |