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US6015990A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor memory device and method of manufacturing the same

Assignee: Toshiba Corp
•
Filing: 1998-02-26
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Granted: 2000-01-18
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Expires: 2018-02-26
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Abstract

Abstract A semiconductor memory device comprises a matrix of memory cells, each having a transistor and a capacitor. A first electrode, a dielectric film and a second electrode are sequentially staked on a silicon monocrystalline substrate and epitaxially grown to form a capacitor having a multilayer structure. Then, an SOI layer is formed on the monocrystalline substrate carrying thereon the capacitor with an insulator film interposed therebetween. A source/drain diffusion layer is formed in the SOI layer and a gate electrode is formed to produce a MOS transistor. Either the source or the drain of the source/drain diffusion layer of the transistor is connected to the second electrode by way of the polysilicon layer in the contact hole running through the SOI layer and the insulator film layer.

Inventors

  • 👤 Katsuhiko Hieda
  • 👤 Tsunetoshi Arikado
  • 👤 Katsuya Okumura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 16:52
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/036; H10B12/05; H10B12/053; H10B12/30; H10B12/31; H10B12/33; H10B12/34; H10D; H10D86/00; H10D86/01

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 146 words
A semiconductor element comprising: a semiconductor section carrying a transistor formed therein; and a capacitor section having a capacitor, wherein the capacitor includes epitaxially grown first and second electrodes, and an epitaxially grown dielectric film is arranged between the first and second electrodes, also wherein the transistor and the capacitor form a memory cell, a first electrode and a second electrode are sequentially stacked above a monocrystalline substrate to produce a multilayer structure, the transistor is formed on the capacitor with an insulation layer interposed therebetween, and either a source or a drain of the transistor is connected to the second electrode by way of a contact hole formed through the insulation layer, further wherein the first electrode is made of an electroconductive material having a crystal structure with a tetragonal system type (100)-plane and the dielectric film has a tetragonal system type perovskite crystal structure.
Claim 2
Dependent Claim 146 words
A semiconductor element comprising: a semiconductor section carrying a transistor formed therein; and a capacitor section having a capacitor, wherein the capacitor includes epitaxially grown first and second electrodes, and an epitaxially grown dielectric film is arranged between the first and second electrodes, also wherein the transistor and the capacitor form a memory cell, a first electrode and a second electrode are sequentially stacked above a monocrystalline substrate to produce a multilayer structure, the transistor is formed on the capacitor with an insulation layer interposed therebetween, and either a source or a drain of the transistor is connected to the second electrode by way of a contact hole formed through the insulation layer, further wherein the first electrode is made of an electroconductive material having a crystal structure with a tetragonal system type (100)-plane and the dielectric film has a tetragonal system type perovskite crystal structure.
Claim 3
Dependent Claim 17 words
A semiconductor memory device according to claim 1, wherein the monocrystalline substrate is made of (100)-oriented silicon.
Claim 4
Dependent Claim 18 words
A semiconductor memory device according to claim 1, wherein the dielectric film is highly dielectric at room temperature.
Claim 5
Dependent Claim 17 words
A semiconductor memory device according to claim 1, wherein the dielectric film is ferroelectric at room temperature.
Claim 6
Dependent Claim 50 words
A semiconductor memory device according to claim 1 and comprising a plurality of memory cells, wherein the first electrode operates as a common plate electrode adapted to provide a common electric potential to the plurality of memory cells and the second electrode operates independently for each of the memory cells.
Claim 7
Dependent Claim 61 words
A semiconductor memory device according to claim 1 and comprising a plurality of memory cells, wherein the dielectric film is ferroelectric at room temperature and the first electrode is formed as a common plate electrode adapted to provide a common electric potential to the plurality of memory cells and the second electrode is formed independently for each of the memory cells.
Claim 8
Dependent Claim 32 words
A semiconductor memory device according to claim 1, wherein the capacitor has a barrier layer having a lattice constant close to that of Si between the first electrode and the monocrystalline substrate.
Claim 9
Dependent Claim 156 words
A semiconductor element comprising: a semiconductor section carrying a transistor formed therein; and a capacitor section having a capacitor, wherein the capacitor includes epitaxially grown first and second electrodes, and an epitaxially grown dielectric film arranged between the first and second electrodes; also wherein the transistor section includes an element isolation region, an insulator film formed on a gate electrode of the transistor and an epitaxially grown monocrystalline Si section; the top surface of the monocrystalline Si section being substantially level with those of the element isolation region and the insulator film; the capacitor section having a buffer layer epitaxially grown on the monocrystalline Si section, the first electrode, the dielectric film and the second electrode being sequentially stacked on the buffer layer; further wherein the first electrode is made of an eletroconductive material having a crystal structure with a tetragonal system type (100)-plane and the dielectric film has a tetragonal system type perovskite crystal structure.
Claim 10
Dependent Claim 156 words
A semiconductor element comprising: a semiconductor section carrying a transistor formed therein; and a capacitor section having a capacitor, wherein the capacitor includes epitaxially grown first and second electrodes, and an epitaxially grown dielectric film arranged between the first and second electrodes; also wherein the transistor section includes an element isolation region, an insulator film formed on a gate electrode of the transistor and an epitaxially grown monocrystalline Si section; the top surface of the monocrystalline Si section being substantially level with those of the element isolation region and the insulator film; the capacitor section having a buffer layer epitaxially grown on the monocrystalline Si section, the first electrode, the dielectric film and the second electrode being sequentially stacked on the buffer layer; further wherein the first electrode is made of an eletroconductive material having a crystal structure with a tetragonal system type (100)-plane and the dielectric film has a tetragonal system type perovskite crystal structure.
Claim 11
Dependent Claim 18 words
A semiconductor memory device according to claim 8, wherein the dielectric film is highly dielectric at room temperature.
Claim 12
Dependent Claim 17 words
A semiconductor memory device according to claim 8, wherein the dielectric film is ferroelectric at room temperature.
Claim 13
Dependent Claim 28 words
A semiconductor memory device according to claim 8, where the dielectric film has is a monocrystalline film of a perovskite type oxide containing Ba, Sr, Ti and oxygen.
Claim 14
Dependent Claim 42 words
A semiconductor memory device according to claim 8, wherein the buffer layer is made of an electroconductive material having a lattice constant close to that of silicon and the first electrode is made of an electroconductive oxide having a perovskite crystal structure.
Claim 15
Dependent Claim 48 words
A semiconductor memory device according to claim 8, wherein the buffer layer has a double-layered structure of a TiAlN film and a Pt film and the first electrode is made of SrRuO 3 , whereas the dielectric film is made of Ba x Sr 1-x TiO 3 (0.1<x<0.9).
Claim 16
Dependent Claim 58 words
A semiconductor memory device according to claim 8, wherein the buffer layer has a double-layered structure of a TiAlN film and a Pt film and the first electrode is made of SrRuO 3 , whereas the dielectric film is made of Ba x Sr 1-x TiO 3 (0.1<x<0.9) and the second electrode is made of SrRuO 3 .

References Cited (Backward Citations)

US4409608A Cited
US4536785A Cited
US5341016A Cited
JPH08139292A Cited
JPH08195328A Cited
US5889299A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-01-17 2003-07-19 2004-01-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-01-17 2007-07-19 2008-01-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-01-17 2011-07-19 2012-01-18 $7700.00 Window Closed / Lapsed

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