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US4700457A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making multilayer capacitor memory device

Assignee: Mitsubishi Electric Corp
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Filing: 1986-01-27
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Granted: 1987-10-20
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Expires: 2006-01-27
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Abstract

Abstract A semiconductor device comprising a capacitor of a laminated structure and a method of manufacturing thereof, in which first conductive layer and second conductive layer of different materials or different compositions are stacked alternately with dielectric films interposed therebetween and the first conductive layers and the second conductive layers are interconnected respectively at a time by suitably combining a selective etching method and an anisotropic etching method.

Inventors

  • 👤 Takayuki Matsukawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 23:34
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10B; H10B12/00; H10B12/30; Y; Y10; Y10S; Y10S148/00; Y10S148/014

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 173 words
A method of manufacturing of a capacitor included in a semiconductor device formed on a semiconductor substrate, comprising the steps of: forming multiple layered film over the whole surface of said semiconductor substrate by placing alternately first conductive layer and second conductive layer of different etching characteristics with dielectric film therebetween, applying an anisotropic etching process to said multiple layered film formed by said first step so that said multiple layered film remain only in predetermined regions with all the side faces of said multiple layered film being exposed, etching all the side faces of said multiple layered film exposed by said second mentioned step using an etching process preferentially acting on said first conductive layers so that the side faces of said first conductive layers are recessed inward with the side faces of said second conductive layers being kept unchanged, filling the gaps made by said recession of said first conductive layers with an insulating material, and electrically interconnecting said second conductive layers having the exposed side faces by using a conductor.
Claim 2
Independent Claim 173 words
A method of manufacturing of a capacitor included in a semiconductor device formed on a semiconductor substrate, comprising the steps of: forming multiple layered film over the whole surface of said semiconductor substrate by placing alternately first conductive layer and second conductive layer of different etching characteristics with dielectric film therebetween, applying an anisotropic etching process to said multiple layered film formed by said first step so that said multiple layered film remain only in predetermined regions with all the side faces of said multiple layered film being exposed, etching all the side faces of said multiple layered film exposed by said second mentioned step using an etching process preferentially acting on said first conductive layers so that the side faces of said first conductive layers are recessed inward with the side faces of said second conductive layers being kept unchanged, filling the gaps made by said recession of said first conductive layers with an insulating material, and electrically interconnecting said second conductive layers having the exposed side faces by using a conductor.
Claim 3
Dependent Claim 39 words
A manufacturing method in accordance with claim 1, wherein said first conductive layers and said second conductive layers are formed on said semiconductor substrate alternately in the order of first to second layers with said dielectric film being interposed.
Claim 4
Dependent Claim 39 words
A manufacturing method in accordance with claim 1, wherein said second conductive layers and said first conductive layers are formed on said semiconductor substrate alternately in the order of second to first layers with said dielectric film being interposed.
Claim 5
Dependent Claim 78 words
A manufacturing method in accordance with claim 1, wherein said conductor used for said electrical interconnection is formed of polysilicon containing an impurity which is to be diffused in said semiconductor substrate so as to form a conductive region, said conductor being in contact with said semiconductor substrate, and said impurity is thermally diffused from said conductor into said semiconductor substrate to form an impurity diffusion region whereby said conductor is electrically connected with said impurity diffusion region.
Claim 6
Dependent Claim 78 words
A manufacturing method in accordance with claim 1, wherein said conductor used for said electrical interconnection is formed of silicide containing an impurity which is to be diffused in said semiconductor substrate so as to form a conductive region, said conductor being in contact with said semiconductor substrate, and said impurity is thermally diffused from said conductor into said semiconductor substrate to form an impurity diffusion region whereby said conductor is electrically connected with said impurity diffusion region.
Claim 7
Dependent Claim 23 words
A manufacturing method in accordance with claim 1, wherein said semiconductor device is a semiconductor memory device for storing information in said capacitor.

References Cited (Backward Citations)

US4156249A Cited
US4460911A Cited
US4451841A Cited
DE2728928A1 Cited
JPS568871A Cited
JPS57112066A Cited
US4455568A Cited
US4441249A Cited
US4507171A Cited
JPS5989450A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-10-19 1991-04-20 1991-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-10-19 1995-04-20 1995-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-10-19 1999-04-20 1999-10-20 $7700.00 Window Closed / Lapsed

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