EP0451389A1
Expired / Lapsed
EP
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Nonvolatile semiconductor memory and method of making same
Assignee: Panasonic Holdings Corp
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Filing: 1990-04-11
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Granted: —
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Expires: 2010-04-11
Abstract
Abstract A nonvolatile semiconductor memory comprising a silicon semiconductor substrate (11) and formed thereon a gate insulating film (12), wherein an ion belonging to the same Group IV in the periodic table as the ion of said silicon semiconductor substrate belongs is shot into said gate insulating film (12) by ion implantation in a dose of not less than 10¹⁶ cm⁻² to form an ion-implanted region (13) therein in such a way that a peak of impurity density of the ion is present at the gate insulating film side from the interface between said semiconductor substrate (11) and said gate insulating film (12). Also disclosed are an MOS integrated circuit comprising the nonvolatile semiconductor memory, and a method of making the nonvolatile semiconductor memory.
Inventors
- 👤 Takashi Ohzone
- 👤 Takashi Hori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 08:12
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/69; H10D64/00; H10D64/01; H10D64/031; H10D64/037
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
119 words
A nonvolatile semiconductor memory comprising a silicon semiconductor substrate and formed thereon a gate insulating film, wherein; an ion belonging to the same Group IV in the periodic table as the ion of said silicon semiconductor substrate is shot into said gate insulating film by ion implantation in a dose of not less than 10¹⁶ cm⁻² to form an ion-implanted region therein in such a way that a peak of impurity density of the ion is present at the gate insulating film side of the interface between said semiconductor substrate and said gate insulating film; and an electric charge is controlled to be injected in or released from said ion-implanted region so that a nonvolatile memory effect is controlled.
Claim 2
Dependent Claim
20 words
A nonvolatile semiconductor memory according to Claim 1, wherein an Si⁺ ion is used as said ion of Group IV.
Claim 3
Dependent Claim
126 words
A nonvolatile semiconductor memory comprising a silicon semiconductor substrate and formed thereon a gate insulating film, wherein; an ion belonging to the same Group IV in the periodic table as the ion of said silicon semiconductor substrate is shot into said gate insulating film by ion implantation in a dose of not less than 10¹⁶ cm⁻² to selectively form an ion-implanted region at part of said gate insulating film in such a way that a peak of impurity density of the ion is present at the gate insulating film side of the interface between said semiconductor substrate and said gate insulating film; and an electric charge is controlled to be injected in or released from said ion-implanted region so that a nonvolatile memory effect is controlled.
Claim 4
Dependent Claim
20 words
A nonvolatile semiconductor memory according to Claim 3, wherein an Si⁺ ion is used as said ion of Group IV.
Claim 5
Dependent Claim
161 words
A memory-oxide-semiconductor integrated circuit comprising a silicon substrate and, integrated on the same silicon substrate; i) a nonvolatile semiconductor memory comprising a silicon semiconductor substrate and formed thereon a gate insulating film, wherein; an ion belonging to the same Group IV in the periodic table as the ion of said silicon semiconductor substrate is shot into said gate insulating film by ion implantation in a dose of not less than 10¹⁶ cm⁻² to form an ion-implanted region therein or at part of the gate insulating film in such a way that a peak of impurity density of the ion is present at the gate insulating film side of the interface between said semiconductor substrate and said gate insulating film; and an electric charge is controlled to be injected in or released from said ion-implanted region so that a nonvolatile memory effect is controlled; and ii) a memory-oxide-semiconductor transistor comprising a gate insulating film in which no Group IV ion is implanted.
Claim 6
Dependent Claim
25 words
A memory-oxide-semiconductor integrated circuit according to Claim 5, wherein, in said nonvolatile semiconductor memory, an Si⁺ ion is used as said ion of Group IV.
Claim 7
Independent Claim
49 words
A method of preparing a nonvolatile semiconductor memory, comprising the steps of forming a gate insulating film on a silicon semiconductor substrate, implanting a Group IV ion in said gate insulating film to form an ion-implanted region, and forming a gate electrode, a source region, and a drain region.
Claim 8
Dependent Claim
42 words
A method of preparing a nonvolatile semiconductor memory according to Claim 7, wherein an Si⁺ ion is used as said Group IV ion, and said ion is implanted in a dose of not less than 10¹⁶ cm⁻² to form said ion-implanted region.
Claim 9
Independent Claim
57 words
A method of preparing a nonvolatile semiconductor memory, comprising the steps of forming a gate insulating film on a silicon semiconductor substrate, implanting an Si⁺ ion in said gate insulating film in a dose of not less than 10¹⁶ cm⁻² to form an ion-implanted region, and forming a gate electrode, a source region, and a drain region.
References Cited (Backward Citations)
US3649884A
Cited
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