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US5912486A Expired / Lapsed US ⏱️ 0.0 years remaining

Pb/Bi-containing high-dielectric constant oxides using a non-Pb/Bi-containing perovskite as a buffer layer

Assignee: Texas Instruments Inc
•
Filing: 1997-04-17
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Granted: 1999-06-15
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Expires: 2017-04-17
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Abstract

Abstract This is a method for fabricating a structure useful in semiconductor circuitry. The method comprises: growing a buffer layer of non-Pb/Bi-containing high-dielectric constant oxide layer directly or indirectly on a semiconductor substrate; and depositing a Pb/Bi-containing high-dielectric constant oxide on the buffer layer. Alternately this may be a structure useful in semiconductor circuitry, comprising: a buffer layer 26 of non-lead-containing high-dielectric constant oxide layer directly or indirectly on a semiconductor substrate 10; and a lead-containing high-dielectric constant oxide 28 on the buffer layer. Preferably a germanium layer 12 is epitaxially grown on the semiconductor substrate and the buffer layer is grown on the germanium layer. When the substrate is silicon, the non-Pb/Bi-containing high-dielectric constant oxide layer is preferably less than about 10 nm thick. A second non-Pb/Bi-containing high-dielectric constant oxide layer 30 may be grown on top of the Pb/Bi-containing high-dielectric constant oxide and a conducting layer (top electrode 32) may also be grown on the second non-Pb/Bi-containing high-dielectric constant oxide layer.

Inventors

  • 👤 Scott R. Summerfelt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 01:50
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/0134; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684; H10D64/01342; H10D64/60; H10D64/66; H10D64/68; H10D64/681; H10D64/685; H10D64/691; H10P14/65; H10P14/6502; H10P14/6506; H10P14/63; H10P14/6326; H10P14/6349; H10P14/69; H10P14/692; H10P14/6938; H10P14/6939; H10P14/69396; H10P14/69398; Y; Y10; Y10S; Y10S148/00; Y10S148/014; Y10S148/118; Y10S438/00; Y10S438/967

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 59 words
A structure useful in semiconductor circuitry, comprising: an epitaxial germanium layer overlying a semiconductor substrate; a first epitaxial buffer layer of substantially Pb and Bi free high-dielectric constant oxide on said germanium layer; and a second epitaxial high-dielectric constant oxide layer comprising an element selected from the group consisting of: Pb, Bi, and combinations thereof, on said buffer layer.
Claim 2
Dependent Claim 59 words
A structure useful in semiconductor circuitry, comprising: an epitaxial germanium layer overlying a semiconductor substrate; a first epitaxial buffer layer of substantially Pb and Bi free high-dielectric constant oxide on said germanium layer; and a second epitaxial high-dielectric constant oxide layer comprising an element selected from the group consisting of: Pb, Bi, and combinations thereof, on said buffer layer.
Claim 3
Dependent Claim 10 words
The structure of claim 1, wherein said substrate is silicon.
Claim 4
Dependent Claim 16 words
The structure of claim 1, wherein said germanium layer is less than about 1 nm thick.
Claim 5
Dependent Claim 11 words
The structure of claim 1, wherein said substrate is gallium arsenide.
Claim 6
Dependent Claim 31 words
The structure of claim 1, wherein a second epitaxial buffer layer of substantially Pb and Bi free, high-dielectric constant oxide is on top of said second epitaxial high-dielectric constant oxide layer.
Claim 7
Dependent Claim 18 words
The structure of claim 5, wherein a conducting layer is on top of said second epitaxial buffer layer.
Claim 8
Dependent Claim 23 words
The structure of claim 1, wherein said substantially Pb and Bi free, high-dielectric constant oxide layer is less than about 10 nm thick.
Claim 9
Dependent Claim 13 words
The structure of claim 1, wherein both said high-dielectric constant oxides are titanates.
Claim 10
Dependent Claim 19 words
The structure of claim 8, wherein said substantially Pb and Bi free high-dielectric constant oxide is barium strontium titanate.
Claim 11
Dependent Claim 16 words
The structure of claim 1, wherein said second high-dielectric constant oxide layer is lead zirconate titanate.
Claim 12
Dependent Claim 14 words
The structure of claim 1, wherein both said high-dielectric constant oxides are ferroelectric oxides.
Claim 13
Dependent Claim 11 words
The structure of claim 1, wherein said structure is a capacitor.
Claim 14
Dependent Claim 41 words
A structure useful in semiconductor circuitry, comprising: an epitaxial germanium layer overlying a semiconductor substrate; a first epitaxial buffer layer of barium strontium titanate on said germanium layer; and an epitaxial lead zirconate titanate layer on said first epitaxial buffer layer.
Claim 15
Dependent Claim 41 words
A structure useful in semiconductor circuitry, comprising: an epitaxial germanium layer overlying a semiconductor substrate; a first epitaxial buffer layer of barium strontium titanate on said germanium layer; and an epitaxial lead zirconate titanate layer on said first epitaxial buffer layer.
Claim 16
Dependent Claim 25 words
The structure of claim 13, wherein a second epitaxial buffer layer of barium strontium titanate is on top of said epitaxial lead zirconate titanate layer.
Claim 17
Dependent Claim 18 words
The structure of claim 14, wherein a conducting layer is on top of said second epitaxial buffer layer.
Claim 18
Dependent Claim 10 words
The structure of claim 13, wherein said substrate is silicon.

References Cited (Backward Citations)

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WO1991013465A1 Cited
JPH0488685A Cited
US5173835A Cited
EP0540963A1 Cited
US5338951A Cited
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