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Semiconductor memory apparatus

Assignee: Rohm Co Ltd
•
Filing: 1992-10-21
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Granted: 1994-07-26
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Expires: 2012-10-21
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Abstract

Abstract A high dielectric film instead of an oxidizing film conventionally used is used in the non-volatile memory of an MoNoS construction. Using a mixed film composed of a high dielectric constant film and an amorphous insulating film for the trap film, the ratio of the voltage applied to the tunnel oxidizing film is increased so that writing and erasing operations can be effected with a low voltage. Penetration of the electrons into the electrode and the flow of positive holes from the electrode are prevented so as to increase the flow efficiency.

Inventors

  • 👤 Noriyuki Shimoji
  • 👤 Takanori Ozawa
  • 👤 Hironobu Nakao

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 01:54
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01342; H10D30/00; H10D30/60; H10D30/69; H10D64/60; H10D64/66; H10D64/68; H10D64/681; H10D64/685; H10D64/691

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 63 words
A semiconductor memory apparatus comprising a tunnel oxidizing film formed on a Si substrate, a mixed film composed of a high dielectric constant insulating film and an amorphous insulating film formed on the tunnel oxidizing film, a metallic film formed on the mixed film, a high dielectric film formed on the metallic film, and a gate electrode formed on the high dielectric film.
Claim 2
Dependent Claim 63 words
A semiconductor memory apparatus comprising a tunnel oxidizing film formed on a Si substrate, a mixed film composed of a high dielectric constant insulating film and an amorphous insulating film formed on the tunnel oxidizing film, a metallic film formed on the mixed film, a high dielectric film formed on the metallic film, and a gate electrode formed on the high dielectric film.
Claim 3
Dependent Claim 44 words
The semiconductor memory apparatus as defined in claim 1, wherein the high dielectric film has a band gap which prevents the penetration of electrons into the electrode and the flow of positive holes from the electrode, thereby increasing the flow efficiency of the electrons.
Claim 4
Dependent Claim 27 words
The semiconductor memory apparatus as defined in claim 1, wherein the high dielectric film is a film having a dielectric constant of Al 2 O 3 .

References Cited (Backward Citations)

US3731163A Cited
US4360900A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-07-25 1998-01-24 1998-07-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-07-25 2002-01-24 2002-07-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-07-25 2006-01-24 2006-07-26 $7700.00 Window Closed / Lapsed

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