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Semiconductor non-volatile memory device and method of manufacturing the same

Assignee: Toshiba Corp
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Filing: 1992-12-08
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Granted: 1994-06-28
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Expires: 2012-12-08
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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 2026-11-04 12:27
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: 3
Claim 1
Independent Claim 141 words
A semiconductor non-volatile memory device comprising: a semiconductor substrate; a first diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate; a second diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate, said second region constituting a control gate; a third diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate such that said third diffusion region is spaced from said first diffusion region by a channel region; and a floating gate spaced from said first diffusion region by a first insulating film portion having a first thickness, from said second diffusion region by a second and from said first diffusion region by a thid insulating film portion having a third thickness which is less than said second thickness.
Claim 2
Dependent Claim 141 words
A semiconductor non-volatile memory device comprising: a semiconductor substrate; a first diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate; a second diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate, said second region constituting a control gate; a third diffusion region in said semiconductor substrate of a conductivity type opposite to that of said semiconductor substrate such that said third diffusion region is spaced from said first diffusion region by a channel region; and a floating gate spaced from said first diffusion region by a first insulating film portion having a first thickness, from said second diffusion region by a second and from said first diffusion region by a thid insulating film portion having a third thickness which is less than said second thickness.
Claim 3
Dependent Claim 24 words
The semiconductor non-volatile memory device according to claim 1, wherein said first and second insulating film portions are two different types of insulating film.

References Cited (Backward Citations)

US4288863A Cited
US4425631A Cited
US4823316A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-06-27 1997-12-27 1998-06-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-06-27 2001-12-27 2002-06-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-06-27 2005-12-27 2006-06-28 $7700.00 Window Closed / Lapsed

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