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US5670808A Expired / Lapsed US ⏱️ 0.0 years remaining

Metal oxide capacitor with a WNX electrode

Assignee: Toshiba Corp
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Filing: 1996-01-25
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Granted: 1997-09-23
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Expires: 2016-01-25
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Abstract

Abstract A semiconductor device in which an SiO 2 film and a first wiring layer are arranged in this order on a GaAs substrate. A capacitor is formed on the first wiring layer. The capacitor includes a lower electrode which has a multi-layer structure consisting of a Ti layer, an Mo layer, and a Pt layer in this order from underside. The capacitor also includes a dielectric film made of strontium titanate. The capacitor further includes an upper electrode which has a multi-layer structure consisting of a WN x layer (120 um) and a W layer (300 nm) in this order from underside. That surface of the upper electrode, which is in contact with the dielectric film, is defined by the tungsten nitride layer.

Inventors

  • 👤 Kazuya Nishihori
  • 👤 Yoshiaki Kitaura
  • 👤 Yoshikazu Tanabe
  • 👤 Tomonori Aoyama
  • 👤 Kyoichi Suguro
  • 👤 Kumi Okuwada
  • 👤 Shuichi Komatsu
  • 👤 Kazuhide Abe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:38
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/80; H10D84/811; H10D1/00; H10D1/60; H10D1/68; H10D1/692; H10D1/696; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/033; H10D1/682; H10D84/01; H10D84/813

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 68 words
A semiconductor device comprising a capacitor having first and second electrodes, a dielectric film comprising an oxide interposed between said electrodes, and a first contacting surface comprising tungsten nitride interposed between, and contacting, both said dielectric film and said first electrode, wherein said tungsten nitride of said first contacting surface is expressed by WN x and its coefficient x falls in a range of from 0.05 to 0.5.
Claim 2
Dependent Claim 68 words
A semiconductor device comprising a capacitor having first and second electrodes, a dielectric film comprising an oxide interposed between said electrodes, and a first contacting surface comprising tungsten nitride interposed between, and contacting, both said dielectric film and said first electrode, wherein said tungsten nitride of said first contacting surface is expressed by WN x and its coefficient x falls in a range of from 0.05 to 0.5.
Claim 3
Dependent Claim 25 words
The device according to claim 1, wherein said second electrode is in contact with said dielectric film by a second contacting surface comprising tungsten nitride.
Claim 4
Dependent Claim 43 words
The device according to claim 1, wherein said first electrode includes a tungsten nitride layer, a titanium nitride layer, and a barrier metal layer interposed between said tungsten nitride layer and titanium nitride layer, said first contacting surface being said tungsten nitride layer.
Claim 5
Dependent Claim 17 words
The device according to claim 1, wherein said dielectric film is made of a perovskite dielectric substance.
Claim 6
Dependent Claim 29 words
The device according to claim 4, wherein said capacitor is designed to be used at a frequency of 800 MHz or more, and said perovskite dielectric substance is paraelectric.
Claim 7
Dependent Claim 13 words
The device according to claim 5, wherein said perovskite dielectric substance contains strontium.

References Cited (Backward Citations)

JPS5897818A Cited
US5187557A Cited
US5283462A Cited
US5440174A Cited
JPH06275776A Cited
US5486488A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-09-22 2001-03-24 2001-09-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-09-22 2005-03-24 2005-09-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-09-22 2009-03-24 2009-09-23 $7700.00 Window Closed / Lapsed

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