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US5619393A Expired / Lapsed US ⏱️ 0.0 years remaining

High-dielectric-constant material electrodes comprising thin ruthenium dioxide layers

Assignee: Texas Instruments Inc
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Filing: 1995-06-07
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Granted: 1997-04-08
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Expires: 2015-06-07
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Abstract

Abstract A preferred embodiment of this invention comprises a thin unreactive film (e.g. ruthenium dioxide 36) contacting a high-dielectric-constant material (e.g. barium strontium titanate 38) to an electrode. The thin unreactive film provides a stable conductive interface between the high-dielectric-constant material layer and the electrode base (e.g palladium 34). As opposed to a standard thin-film layer, the thin unreactive film is generally less than 50 nm thick, preferably less than 35 nm thick, more preferably between 5 nm and 25 nm thick, and most preferably between 10 nm and 20 nm thick. A thin unreactive film can benefit from the advantages of the materials used while avoiding or minimizing many of their disadvantages. A thin unreactive film would generally be substantially less expensive than a standard thin-film layer since much less material can be used while not significantly affecting the surface area of the electrode in contact with the HDC material. These structures may also be used for multilayer capacitors and other thin-film ferroelectric devices such as pyroelectric materials, non-volatile memories, thin-film piezoelectric and thin-film electro-optic oxides.

Inventors

  • 👤 Scott R. Summerfelt
  • 👤 Howard R. Beratan
  • 👤 Bruce E. Gnade

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 12:17
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/692; Y; Y10; Y10T; Y10T29/00; Y10T29/43; Y10T29/435

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 88 words
A method of forming a microelectronic structure, said method comprising: (a) forming a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) forming a lower thin ruthenium dioxide film less than 35 nm thick on said lower electrode base, including on said sidewalls; and (c) forming a high-dielectric-constant material layer on said lower thin ruthenium dioxide film, whereby the lower thin ruthenium dioxide film provides a stable conductive interface between the high-dielectric-constant material layer and the lower electrode base.
Claim 2
Independent Claim 88 words
A method of forming a microelectronic structure, said method comprising: (a) forming a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) forming a lower thin ruthenium dioxide film less than 35 nm thick on said lower electrode base, including on said sidewalls; and (c) forming a high-dielectric-constant material layer on said lower thin ruthenium dioxide film, whereby the lower thin ruthenium dioxide film provides a stable conductive interface between the high-dielectric-constant material layer and the lower electrode base.
Claim 3
Dependent Claim 23 words
The method according to claim 1, wherein said lower electrode base is less than 500 nm wide and greater than 250 nm thick.
Claim 4
Dependent Claim 21 words
The method according to claim 1, wherein said lower electrode base comprises a high melting point noble or platinum group metal.
Claim 5
Dependent Claim 15 words
The method according to claim 1, wherein said lower electrode base comprises a conductive nitride.
Claim 6
Dependent Claim 15 words
The method according to claim 1, wherein said lower electrode base comprises a conductive oxide.
Claim 7
Dependent Claim 51 words
The method according to claim 1, wherein said high-dielectric-constant material layer is selected from the group consisting of: barium strontium titanate, lead zirconate titanate, lead lanthanum titanate, lead lanthanum zirconate titanate, bismuth titanate, potassium tantalate, lead scandium tantalate, lead niobate, lead zinc niobate, potassium niobate, lead magnesium niobate, and combinations thereof.
Claim 8
Dependent Claim 21 words
The method according to claim 1, said method further comprising forming an upper thin unreactive film on said high-dielectric-constant material layer.
Claim 9
Dependent Claim 78 words
A microelectronic structure comprising: (a) a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) a lower thin ruthenium dioxide film less than 35 nm thick overlying said lower electrode base, including said sidewalls; and (c) a high-dielectric-constant material layer overlying said lower thin ruthenium dioxide film, whereby the lower thin ruthenium dioxide film provides a stable conductive interface between the high-dielectric-constant material layer and the lower electrode base.
Claim 10
Dependent Claim 78 words
A microelectronic structure comprising: (a) a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) a lower thin ruthenium dioxide film less than 35 nm thick overlying said lower electrode base, including said sidewalls; and (c) a high-dielectric-constant material layer overlying said lower thin ruthenium dioxide film, whereby the lower thin ruthenium dioxide film provides a stable conductive interface between the high-dielectric-constant material layer and the lower electrode base.
Claim 11
Dependent Claim 22 words
The structure of claim 8, wherein said lower electrode base is less than 500 nm wide and greater than 250 nm thick.
Claim 12
Dependent Claim 22 words
The structure of claim 9, wherein said lower electrode base is less than 400 nm wide and greater than 400 nm thick.
Claim 13
Dependent Claim 22 words
The structure of claim 10, wherein said lower electrode base is less than 300 nm wide and greater than 500 nm thick.
Claim 14
Dependent Claim 20 words
The structure of claim 8, wherein said lower electrode base comprises a high melting point noble or platinum group metal.
Claim 15
Dependent Claim 12 words
The structure of claim 12, wherein said lower electrode base comprises palladium.
Claim 16
Dependent Claim 14 words
The structure of claim 8, wherein said lower electrode base comprises a conductive nitride.
Claim 17
Dependent Claim 27 words
The structure of claim 14, wherein said conductive nitride is selected from the group consisting of: titanium nitride, tantalum nitride, zirconium nitride, hafnium nitride, and combinations thereof.
Claim 18
Dependent Claim 14 words
The structure of claim 8, wherein said lower electrode base comprises a conductive oxide.
Claim 19
Dependent Claim 29 words
The structure of claim 16, wherein said conductive oxide is selected from the group consisting of: tin oxide, osmium oxide, rhodium oxide, iridium oxide, indium oxide, and combinations thereof.
Claim 20
Dependent Claim 50 words
The structure of claim 8, wherein said high-dielectric-constant material layer is selected from the group consisting of: barium strontium titanate, lead zirconate titanate, lead lanthanum titanate, lead lanthanum zirconate titanate, bismuth titanate, potassium tantalate, lead scandium tantalate, lead niobate, lead zinc niobate, potassium niobate, lead magnesium niobate, and combinations thereof.
Claim 21
Dependent Claim 17 words
The structure of claim 8, further comprising an upper thin unreactive film overlying said high-dielectric-constant material layer.
Claim 22
Dependent Claim 13 words
The structure of claim 19, wherein said upper unreactive film is ruthenium dioxide.
Claim 23
Dependent Claim 15 words
The structure of claim 19, further comprising an upper electrode overlying said upper unreactive film.
Claim 24
Dependent Claim 93 words
A microelectronic structure comprising: (a) a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) a first ruthenium dioxide film overlying said electrode base, including said sidewalls, wherein said first ruthenium dioxide film is less than 35 nm thick; (c) a high-dielectric-constant material layer overlying said first ruthenium dioxide film; (d) a second ruthenium dioxide film overlying said high-dielectric-constant material layer, wherein said second ruthenium dioxide film is less than 35 nm thick; and (e) an upper electrode overlying said second ruthenium dioxide film.
Claim 25
Dependent Claim 93 words
A microelectronic structure comprising: (a) a non-Ru, non-RuO 2 conductive lower electrode base, comprising sidewalls with an aspect ratio of at least 1:2; (b) a first ruthenium dioxide film overlying said electrode base, including said sidewalls, wherein said first ruthenium dioxide film is less than 35 nm thick; (c) a high-dielectric-constant material layer overlying said first ruthenium dioxide film; (d) a second ruthenium dioxide film overlying said high-dielectric-constant material layer, wherein said second ruthenium dioxide film is less than 35 nm thick; and (e) an upper electrode overlying said second ruthenium dioxide film.

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Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-04-07 2000-10-07 2001-04-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-04-07 2004-10-07 2005-04-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-04-07 2008-10-07 2009-04-08 $7700.00 Window Closed / Lapsed

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