US5532181A
Expired / Lapsed
US
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Method of manufacturing semiconductor non-volatile memory device having different gate insulating thicknesses
Assignee: Toshiba Corp
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Filing: 1994-04-05
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Granted: 1996-07-02
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Expires: 2014-04-05
Abstract
Abstract According to this invention, a semiconductor non-volatile memory device includes a semiconductor substrate, insulating films formed on the semiconductor substrate and having at least two types of gate insulating films having different thicknesses and a first conductive film formed on the insulating films and electrically floating from the semiconductor substrate through the insulating films. These at least two types of gate insulating films include a first insulating film formed on said semiconductor substrate and a first diffusion layer of a conductivity type and a second insulating film formed on said semiconductor substrate and a second diffusion layer, of the opposite conductivity type, which is isolated from the first diffusion layer. The first conductive film is formed on the first and second insulating films. A part of the first insulating film between the first conductive film and the first diffusion layer is constituted by a third insulating film having a thickness smaller than that of the first insulating film.
Inventors
- 👤 Masataka Takebuchi
- 👤 Daisuke Tohyama
- 👤 Hidemitsu Ogura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:06
CPC Classifications
H; H10; H10B; H10B41/00; H10B41/40; H10B41/41; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0411; H10D30/60; H10D30/68; H10D30/681; H10D30/683
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
112 words
A method of manufacturing a semiconductor nonvolatile memory device, comprising the steps of: performing dement isolation to isolate an element active region from a field region; performing photoetching of a part of said element active region; selectively implanting ions; forming a first insulating film; etching a part of said first insulating film using photoetching; forming a second insulating film; etching parts of said first and second insulating films using photoetching; forming a third insulating film; and depositing a first polysilicon layer, wherein id first insulating film is a high breakdown voltage insulating film, said second insulating film is a gate insulating film, and said third insulating film is a tunnel insulating film.
Claim 2
Independent Claim
112 words
A method of manufacturing a semiconductor nonvolatile memory device, comprising the steps of: performing dement isolation to isolate an element active region from a field region; performing photoetching of a part of said element active region; selectively implanting ions; forming a first insulating film; etching a part of said first insulating film using photoetching; forming a second insulating film; etching parts of said first and second insulating films using photoetching; forming a third insulating film; and depositing a first polysilicon layer, wherein id first insulating film is a high breakdown voltage insulating film, said second insulating film is a gate insulating film, and said third insulating film is a tunnel insulating film.
Claim 3
Independent Claim
131 words
A method of manufacturing a semiconductor device, comprising the steps of: forming a first insulating film having a first film thickness on a semiconductor substrate; masking a first portion of a surface region of said first insulating film with a first photoresist using photoetching; implanting impurity ions in the semiconductor substrate through a first exposed part of said first insulating film; removing said first photoresist; masking a second portion of the surface region of said first insulating film with a second photoresist using photoetching; removing a second exposed part of said first insulating film; removing said second photoresist; and forming a second insulating film having a second film thickness, wherein said first insulating film is a high breakdown voltage insulating film and said second insulating film is a gate insulating film.
Claim 4
Independent Claim
131 words
A method of manufacturing a semiconductor device, comprising the steps of: forming a first insulating film having a first film thickness on a semiconductor substrate; masking a first portion of a surface region of said first insulating film with a first photoresist using photoetching; implanting impurity ions in the semiconductor substrate through a first exposed part of said first insulating film; removing said first photoresist; masking a second portion of the surface region of said first insulating film with a second photoresist using photoetching; removing a second exposed part of said first insulating film; removing said second photoresist; and forming a second insulating film having a second film thickness, wherein said first insulating film is a high breakdown voltage insulating film and said second insulating film is a gate insulating film.
Claim 5
Independent Claim
139 words
A method of manufacturing a semiconductor device, comprising the steps of: forming a first insulating film having a first film thickness on a semiconductor substrate; masking a part of a surface region of said first insulating film with a first photoresist using photoetching; removing an exposed part of said first insulating film; removing said first photoresist; forming a second insulating m having a second film thickness; masking a part of a surface region of said second insulating film with a second photoresist using photoetching; removing an exposed part of said second insulating film; removing said second photoresist; and forming a third insulating film having a third film thickness, wherein said first insulating film is a high breakdown voltage insulating film, said second insulating film is a gate insulating film, and said third insulating film is a tunnel insulating, film.
Claim 6
Independent Claim
139 words
A method of manufacturing a semiconductor device, comprising the steps of: forming a first insulating film having a first film thickness on a semiconductor substrate; masking a part of a surface region of said first insulating film with a first photoresist using photoetching; removing an exposed part of said first insulating film; removing said first photoresist; forming a second insulating m having a second film thickness; masking a part of a surface region of said second insulating film with a second photoresist using photoetching; removing an exposed part of said second insulating film; removing said second photoresist; and forming a third insulating film having a third film thickness, wherein said first insulating film is a high breakdown voltage insulating film, said second insulating film is a gate insulating film, and said third insulating film is a tunnel insulating, film.
Claim 7
Dependent Claim
53 words
A method according to claim 2, further comprising the steps of: masking a part of a surface region of said second oxide film with a third photoresist using photoetching; removing an exposed part of said second oxide film removing said third photoresist; and forming a third insulating film having a third film thickness.
Claim 8
Dependent Claim
51 words
A method according to claim 1, further comprising the steps of: diffusing an impurity in said first polysilicon layer; masking a part of a surface region of said first polysilicon layer with a second photoresist using photoetching; removing an exposed part of said first polysilicon layer; and removing said second photoresist.
Claim 9
Dependent Claim
56 words
A method according to claim 2, further comprising the steps of; forming a first polysilicon layer; diffusing an impurity in said first polysilicon layer; masking a part of a surface region of said first polysilicon layer with a third photoresist using photoetching; removing an exposed part of said first polysilicon layer; and removing said third photoresist.
Claim 10
Dependent Claim
56 words
A method according to claim 3, further comprising the steps of: forming a first polysilicon layer; diffusing an impurity in said first polysilicon layer; masking a part of a surface region of said first polysilicon layer with a third photoresist using photoetching; removing an exposed part of said first polysilicon layer; and removing said third photoresist.
Claim 11
Dependent Claim
56 words
A method according to claim 4, further comprising the steps of: forming a first polysilicon layer; diffusing an impurity in said first polysilicon layer; masking a part of a surface region of said first polysilicon layer with a fourth photoresist using photoetching; removing an exposed part of said first polysilicon layer; and removing said fourth photoresist.
Claim 12
Independent Claim
105 words
A method of manufacturing a semiconductor nonvolatile memory device, comprising the steps of: performing element isolation to isolate a first region on a semiconductor substrate from a second region on said semiconductor substrate; forming a first insulating film on said first and second regions; removing said first insulating film from said second region using photoetching; selectively implanting ions in said second region; forming a second insulating film on said second region of said semiconductor substrate; etching a part of said first insulating film using photoetching to form a third insulating film; and depositing a first polysilicon film on said first, second, and third insulating films.
Claim 13
Independent Claim
105 words
A method of manufacturing a semiconductor nonvolatile memory device, comprising the steps of: performing element isolation to isolate a first region on a semiconductor substrate from a second region on said semiconductor substrate; forming a first insulating film on said first and second regions; removing said first insulating film from said second region using photoetching; selectively implanting ions in said second region; forming a second insulating film on said second region of said semiconductor substrate; etching a part of said first insulating film using photoetching to form a third insulating film; and depositing a first polysilicon film on said first, second, and third insulating films.
Claim 14
Dependent Claim
51 words
A method according to claim 9, further comprising the steps of: diffusing an impurity in said first polysilicon film; masking a part of a surface region of said first polysilicon film with a first photoresist using photoetching; removing an exposed part of said first polysilicon film; and removing said first photoresist.
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