Hitachi, Ltd.

Other

Renesas Technology Corp.

Akihiko Satoh

Masahito Takahashi

Takayuki Kawahara

Masataka Kato

Fukuo Owada

Shiro Akamatsu

Takayuki Yoshitake

The present invention discloses a nonvolatile semiconductor memory device including a memory cell array composed of a plurality of memory cells, each of which is formed with a gate insulating film, a floating gate electrode, an insulating film between electrodes, and a control electrode formed respectively in a first conductor type semiconductor area, as well as a second conductor type source area and a second conductor type drain area formed respectively in the first conductor type semiconductor area, and programming and erasing data by controlling the amount of electrons in the floating gate electrode, wherein the nonvolatile semiconductor memory device further includes at least; means for applying a predetermined first operation voltage to the memory cell thereby to inject or eject electrons in or from the floating gate electrode; means for applying a second operation voltage to the memory cell after the application of the first operation voltage to give an electric field with a polarity opposite to that of the electric field applied with the application of the first operation voltage to an insulating film area around the floating gate through which electrons pass when the first operation voltage is applied; means for verifying the threshold voltage in the memory cell after the application of the second operation voltage; and means for deciding whether to repeat the operations following the application of the first operation voltage after the verify operation.

Nonvolatile semiconductor storage device and method for operating the device

It is possible to suppress or prevent so-called write disturbance phenomenon from occurring in write-disabled non-selected memory cells in a semiconductor device, in any selected one of which data can be written electrically by means of the so-called tunneling phenomenon. In a flash memory that can disable writing of data by suppressing injection of electrons in the accumulation layer of each non-selected memory cell in which data is to be written with a writing disable voltage applied to the drain thereof before a write voltage is applied to the control gate electrode of each selected memory cell, the relationship among a writing disable voltage Vwd, a read voltage Vr applied to the drain of a selected memory cell from which data is to be read, and a punch-through withstand voltage BVds between the source and the drain of each selected memory cell is set to satisfy Vr<BVds<Vwd.

Semiconductor device and a integrated circuit card

The present invention aims to provide high integration of a nonvolatile semiconductor memory device having lots of flash memory cells without causing a reduction in its operating speed. A width taken along a gate-width direction, of a lower conductor film for a floating gate electrode is made thinner than a minimum processing size F, and a width taken along the gate-width direction, of an upper conductor film for the floating gate electrode, which is provided with an insulating film disposed on source and drain regions interposed therebetween, is made thicker than the minimum processing size F, whereby a reduction in the ratio of coupling between a control gate electrode and a floating gate electrode due to the scaling down of a unit cell area is restrained.

Nonvolatile semiconductor memory device and a method of manufacturing the same

The present invention discloses a nonvolatile semiconductor memory device including a memory cell array composed of a plurality of memory cells, each of which is formed with a gate insulating film, a floating gate electrode, an insulating film between electrodes, and a control electrode formed respectively in a first conductor type semiconductor area, as well as a second conductor type source area and a second conductor type drain area formed respectively in the firs conductor type semiconductor area, and programming and erasing data by controlling the amount of electrons in the floating gate electrode, wherein the nonvolatile semiconductor memory device further includes at least; means for applying a predetermined first operation voltage to the memory cell thereby to inject or eject electrons in or from the floating gate electrode; means for applying a second operation voltage to the memory cell after the application of the first operation voltage to give an electric field with a polarity opposite to that of the electric field applied with the application of the first operation voltage to an insulating film area around the floating gate through which electrons pass when the first operation voltage is applied; means for verifying the threshold voltage in the memory cell after the application of the second operation voltage; and means for deciding whether to repeat the operations following the application of the first operation voltage after the verify operation.

Nonvolatile semiconductor storage device and method for operating the same

A gate electrode of a field-effect transistor used as a peripheral circuit is constituted by the same gate electrode structure as a double-level gate electrode structure of nonvolatile memory cells, and a contact hole for connecting those conductive films constituting the gate electrode is provided at a location which two-dimensionally overlaps an active area within a plane of the gate electrode. A hole for connecting between the two layers of the gate electrode of a first field-effect transistor used as perpheral circuit is provided at a location which two-dimensionally overlaps the active area within the plane of the gate electrode, and a hole for connecting between the two layers of the gate electrode of a second field-effect transistor used as a peripheral circuit is provided at a location which two-dimensionally overlaps an isolation area within the plane of the gate electrode. The gate length of the first field-effect transistor is longer than the gate length of the second field-effect transistor, and the gate width of the first field-effect transistor is wider than the gate width of the second field-effect transistor.

method for forming capacitors and field effect transistors in a semiconductor integrated circuit device

A gate electrode of a field-effect transistor used as a peripheral circuit is constituted by the same gate electrode structure as a double-level gate electrode structure of nonvolatile memory cells. A hole for connecting the two layers of the gate electrode of a first field-effect transistor used as peripheral circuit is provided at a location which two-dimensionally overlaps the active area within the plane of the gate electrode, and a hole for connecting the two layers of the gate electrode of a second field-effect transistor used as a peripheral circuit is provided at a location which two-dimensionally overlaps an isolation area within the plane of the gate electrode. The gate length of the first field-effect transistor is longer than the gate length of the second field-effect transistor, and the gate width of the first field-effect transistor is wider than the gate width of the second field-effect transistor.

Growing community of inventors

Hachioji, Japan

Akihiko Satoh