Other

Hitachi Device Engineering Co., Ltd.

Renesas Technology Corp.

Hitachi, Ltd.

Hitachi Ulsi Systems Co., Ltd.

Shunichi Saeki

Hideaki Kurata

Naoki Kobayashi

Takashi Kobayashi

Katsutaka Kimura

Hitoshi Kume

Hideakii Kurata

Takayuki Kawahara

Yoshinori Takase

Keiichi Yoshida

Atsushi Nozoe

Shoji Kubono

Michitaro Kanamitsu

A nonvolatile memory device of the present invention performs a programming operation by accumulating a charge in certain capacitance which is provided for each programming memory cell and injecting hot electrons generated when the charge is discharged via the memory cell into a floating gate. Thus, a variation in a programming characteristic of the nonvolatile semiconductor memory device is reduced, thereby realizing high-speed programming operation.

Nonvolatile semiconductor storage device

A semiconductor integrated device having a plurality of memory cells, each including a floating gate, a control gate and an auxiliary gate formed over a side surface of the floating gate through an insulator film. Auxiliary gates coupled to selected memory cells function to generate hot electrons and are alternately arranged with other auxiliary gates functioning to prevent write errors in the non-selected memory cells.

Semiconductor integrated circuit device, production and operation method thereof

A non-volatile memory device is provided which includes a flash memory having a plurality of banks and a bank selection register which can take on states at least equal in number to the number of banks. The bank selection register outputs a signal to point to one of the banks based upon one of the states of the bank selection register. A controller is also provided having a plurality of data buffers corresponding, respectively, to the banks. In addition to word lines, bit lines and memory cells, each bank includes a data register to temporarily hold data to be written to the memory cells. The controller transmits data in the data buffer to the data register of the pointed to bank, while the flash memory writes data held in the data register to the memory cells of another one of the banks.

Non-volatile semiconductor memory device and semiconductor disk device

Semiconductor integrated circuit device including first, second and third gates

A nonvolatile semiconductor memory device includes a memory cell, formed in a well in a substrate and having a source, a drain, a first gate and a second gate. A word line control circuit drives a word line connected to the second gate, a program data holding circuit holds program data, a programming voltage generator circuit applies a programming voltage onto a bit line connected to the drain, and a discrimination circuit verifies the program data. Programming is conducted by applying positive voltages to the second gate and drain, while injecting hot electrons generated in a channel portion in a vicinity of the drain when 0V is applied to the well and source to increase a threshold voltage. Verification is conducted by applying a verify voltage to the second gate, while applying a positive voltage to the drain and 0V to the well and source, thereby verifying whether the positive voltage applied is maintained or comes down to 0V, depending upon the threshold voltage, by means of the discrimination circuit.

Nonvolatile semiconductor memory device

In a semiconductor integrated circuit device including a third gate, the present invention improves miniaturization and operation speed and reduces a defect density of an insulator film. In a semiconductor integrated circuit device including a well of a first conductivity type formed in a semiconductor substrate, a source/drain diffusion layer of a second conductivity type inside the well, a floating gate formed over the semiconductor substrate through an insulator film, a control gate formed and isolated from the floating gate through an insulator film, word lines formed by connecting the control gates and a third gate formed and isolated from the semiconductor substrate, the floating gate and the control gate through an insulator film and different from the floating gate and the control gate, the third gate is buried into a space of the floating gates existing in a direction vertical to the word line and a channel.

In a nonvolatile semiconductor memory device capable of the storage of multivalued data, fast writing can be realized with high reliability. In such a nonvolatile semiconductor memory device for storing multivalued information in one memory cell by setting a plurality of threshold voltages of data, writing of data having one threshold voltage that is the remotest to an erased state is performed prior to writing of the data having the other threshold voltages (write #1). Writing of the data having the other threshold voltages is then sequentially performed starting from the data having the nearer threshold voltage to the erased state. When writing each of the data having the other threshold voltages, writing of the data is simultaneously performed to a memory cell to which the data having the remoter threshold voltage from the erased state (write #2 and write #3).

Programming method of nonvolatile semiconductor memory device

In a nonvolatile semiconductor memory device, in which programming operation of data is conducted by injecting hot electron generated between a source layer and a drain layer of a memory cell into a floating gate between the both layers on an upper potion of surface of a semiconductor, while verification of the data programmed is conducted by making discrimination on whether voltage applied to the drain is kept or not, depending upon a height of a threshold voltage of the memory cell.

A non-volatile semiconductor memory device is capable of having its individual banks controlled separately from the outside, and a semiconductor disk device is capable of proceeding immediately to the next writing to a bank of non-volatile semiconductor memory device which has become ready. Each bank has the independent write operation of data from its data register to memory cells, enabling the transfer of data from the outside to the data register of the bank even during the write operation of other bank from the data register to memory cells thereof.

In a nonvolatile semiconductor memory device capable of the storage of multivalued data, fast writing can be realized with high reliability. In such a nonvolatile semiconductor memory device for storing multivalued information in one memory cell by setting a plurality of threshold voltages of data, writing of data having one threshold voltage that is the remotest to an erased state is performed prior to writing of the data having the other threshold voltages (write &num; ). Writing of the data having the other threshold voltages is then sequentially performed within groups of threshold voltages, starting from the nearer threshold voltage to the erased state within each group. When writing each of the data having the other threshold voltages, writing of the data is performed to a memory cell beginning with those groups having the remoter threshold voltages from the erased state.

Growing community of inventors

Ome, Japan

Shunichi Saeki