Claims
- 1. 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 which is parallel to an interface between said silicon substrate and said gate insulating film, said ion-implanted region having a peak of impurity density of said implanted Group IV which is parallel to and located at said interface;
- forming a gate electrode, a source region, and a drain region.
- 2. A method of preparing a nonvolatile semiconductor memory according to claim 1, wherein an Si.sup.+ ion is used as said Group IV ion, and said ion is implanted in a dose of not less than 10.sup.16 cm.sup.-2 to form said ion-implanted region.
- 3. A method of preparing a nonvolatile semiconductor memory, comprising the steps of forming a gate insulating film on a silicon semiconductor substrate, implanting and Si.sup.+ ion in said gate insulating film in a dose of not less than 10.sup.16 cm.sup.-2 to form an ion-implanted region, and forming a gate electrode, a source region, and a drain region, said ion-implanted region and a horizontally adjacent non-implanted region are selectively formed in a portion of said gate insulating film between said source region and said drain region, with at least one end of the ion-implanted region extending from either said source region or said drain region, with the proviso that said ion-implanted region does not extend across said gate insulating film between said source region and said drain region.
Parent Case Info
This application is a continuation; application of application Ser. No. 07/659,762, filed Feb. 25, 1991, now abandoned, which is a divisional application of application Ser. No. 07/506,610, now abandoned, filed Apr. 10, 1990.
US Referenced Citations (8)
Non-Patent Literature Citations (1)
Entry |
Kalnitsky et al, "Memory Effect and Enhanced Conductivity in Si-Implanted Thermally Grown S10.sub.2 ", IEEE Transactions on Electron Devices, vol. ED-34, No. 11 (Nov. 1987), pp. 2372-2373. |
Divisions (1)
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Number |
Date |
Country |
Parent |
506610 |
Apr 1990 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
659762 |
Feb 1991 |
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