Hynix Semiconductor Inc.

Hyundai Electronics Industries Co. Ltd.

Skhynix Inc.

Ju Yeab Lee

Min Kyu Kim

Nam Kyeong Kim

Byung Jin Ahn

Ju In Kim

Sheung Hee Park

Chi Wook An

Keon Soo Shim

Hee Hyun Chang

Seung Hwan Baik

Keum Hwan Noh

Tae Kyu Kim

Jun In Kim

An operating method of a semiconductor memory device may include receiving a command, outputting a status signal as a busy status while accessing a selected area of the memory cell array in response to the command, changing the status signal from the busy status to a ready status and outputting the status signal after the access is completed, and applying a dummy pulse to an unselected area of the memory cell array in response to the status signal being output as the ready status.

Semiconductor memory device outputting status signal and operating method thereof

A method of programming a nonvolatile memory device comprises performing a first program operation on first memory cells and second memory cells so that threshold voltages of the first and second memory cells have a first reference level lower than a first target level, the first memory cells having the first target level as a first target level, and the second memory cells having a second target level higher than the first target level as a second target level; performing a second program operation on the second memory cells so that the threshold voltages of the second memory cells have a second reference level lower than the second target level; and performing a third program operation on the first and second memory cells to have the respective target levels.

Method of programming nonvolatile memory device

A nonvolatile memory device including a bit line voltage supply unit configured to supply a power source voltage, a second voltage in which a second reference voltage has been subtracted from a third reference voltage, or a third voltage in which a first reference voltage has been subtracted from the third reference voltage according to data stored in a first latch unit, a second latch unit, and a third latch unit included in a page buffer, and a bit line voltage setting unit configured to transfer a voltage of 0 V or an output voltage of the bit line voltage supply unit to a bit line according to the data stored in the first, second, and third latch units.

Nonvolatile memory device and method of programming the same

A nonvolatile memory device includes a cell string, including a drain select transistor coupled to a bit line, a source select transistor coupled to a common source line, and memory cells coupled in series between the drain select transistor and the source select transistor, a latch unit, including a first latch for storing a detection result of a threshold voltage of a second memory cell adjacent to a first memory cell selected from among the memory cells and a second latch for storing a detection result of a threshold voltage of the first memory cell, and a first reset unit electrically coupled between the first and second latches and configured to reset the second latch, during a time in which a read operation is performed on the first memory cell, in response to a first reset signal and the detection result stored in the first latch.

Nonvolatile memory device and method of operating the same

A NAND flash memory device is recovered by applying a predetermined bias to a drain or a source. A negative bias is applied to a cell gate so that electrons are injected into a floating gate of a cell. This narrows the distribution of an erase threshold voltage and minimizes interference from states of peripheral cells.

Recovery method of NAND flash memory device

A flash memory device includes a plurality of memory cell blocks, a control unit, a program speed calculation unit, a voltage generator and a block select unit. Each memory cell block includes a string having a drain select transistor, a plurality of memory cells, a novel cell and a source select transistor. The control unit generates a block select signal in response to an address signal and generates an operation control signal in response to a command signal. The program speed calculation unit decides a level of an initial program voltage based on threshold voltages detected after a program operation of the novel cells. The voltage generator generates operating voltages including the initial program voltage of the level according to the operation control signal. The block select unit transfers the operating voltages to a memory cell block corresponding to the block select signal.

Flash memory device and operating method thereof

A flash memory device may include a memory cell array, a page buffer unit, and a switching element. The page buffer unit may include first and second latches and is configured to program data into the memory cell array and read data from the memory cell array. The switching element enables the first latch during a verify operation of a first program based on a first verify voltage, and enables or disables the first latch in order to execute a verify operation of a second program based on a second verify voltage lower than the first verify voltage depending on whether data to be programmed has been stored in the second latch.

Flash memory device and method of programming the same

In a driving method of a flash memory device including a selected first bit line and an unselected second bit line, a program voltage of a pulse is applied to word lines of all memory cells in a block passing an erase verify operation. After the first and second bit lines are precharged to a predetermined level, a ground voltage is applied to the word lines of all the memory cells in the block. The memory cells are evaluated for a predetermined time shorter than an evaluation time of a read operation. Whether or not a memory cell passing a verify operation exists among the memory cells is sensed. Resultantly, when the memory cell passing the verify operation exists, the memory cells in the block are programmed to a desired level using a predetermined program voltage and a step voltage.

Operation method of flash memory device capable of down-shifting a threshold voltage distribution of memory cells in a post-program verify operation

Provided is a method of reading a flash memory device for depressing read disturb. According to the method, a first voltage is applied to a gate of the drain select transistor to turn on the drain select transistor, and a read voltage is applied to a gate of a selected transistor among the plurality of memory cells. Then, a pass voltage is applied to gates of unselected transistors among the plurality of memory cells. Furthermore, when the pass voltage is applied, a first pass voltage is applied and then a second pass voltage is applied after an elapse of a predetermined time following the applying of the first pass voltage. The second pass voltage has a level different from that of the first pass voltage.

Method of reading flash memory device for depressing read disturb

In an erase verifying method of a NAND flash memory device, a power supply voltage (Vcc) is applied to a second bit line while precharging a first bit line to a first positive voltage. Select transistors are turned on, and a ground voltage is applied to word lines of memory cell transistors. A second positive voltage is applied to source lines to which sources of the select transistors and the memory cell transistors are connected. An erased state of the memory cell transistor is verified according to whether charges accumulated in the first bit line are discharged.

Erase verifying method of NAND flash memory device

A duel program verify operation is performed using first and second verify voltages. In order to reduce the width of a threshold voltage distribution during an incremental step pulse program implementation, data of a corresponding memory cell are verified twice using the first verify voltage and the second verify voltage. During a second verify operation using the second verify voltage, a sensing current is adjusted by controlling voltages applied as a bit line select signal and an evaluation time period. Therefore, the threshold voltage of the memory cell can be measured higher or lower than its actual value and the width of a threshold voltage distribution is reduced.

Program verifying method and programming method of flash memory device

Non-volatile memory devices have a page buffer that can verify pre-erase. A non-volatile memory device may include a cell array having a plurality of strings consisting of memory cells disposed at the intersection regions of bit lines and word lines, and a plurality of page buffers connected to the bit lines through a sensing line. Each of the plurality of page buffers may include a pre-erase detection unit that detects pre-erase in response to a signal of the sensing line in order to verify whether data programmed into the memory cells have been erased, a main erase detection unit that detects main erase in response to a signal of the sensing line in order to verify whether data programmed into the memory cells have been erased, a latch circuit which stores data in response to an output signal of the pre-erase detection unit at the time of pre-erase verify and stores data in response to an output signal of the main erase detection unit at the time of main erase verify, and a verify unit that verifies pass or fail of the pre-erase or main erase in response to a signal of the latch circuit at the time of pre-erase verify or main erase verify.

Non-volatile memory device having page buffer for verifying pre-erase

Disclosed herein is a NAND flash memory device capable of changing a block size. In NAND flash memory devices capable of changing a block size, each memory block is divided into two page groups. Each memory block includes two block switches to select each page group in response to an external address signal. During an erasing operation, the block size is easily variable by applying an erasure voltage to one or two page groups.

NAND flash memory device capable of changing a block size

Disclosed are a page buffer of a flash memory device and data program method using the same. After two data are sequentially stored in a main register (first latch) and a cache register (second latch) provided in a page buffer, they are respectively transferred to an even bit line and an odd bit line at the same time, and a bias needed for a program is applied to cells connected to the even bit line and the odd bit line, respectively, whereby the program is performed at the same time. Therefore, the number and time of operations for data loading, program operation and program verification can be reduced by half and the operating speed of the device can be improved.

Page buffer of flash memory device and data program method using the same

Disclosed is the flash memory device capable of repairing the word line. Fail word lines are repaired using redundancy cells for repairing bit lines by combining X/Y addresses, whereby repair in the direction of the bit line as well as repair in the direction of the word line is made possible. Therefore, it is possible to prevent degradation in the yield and improve reliability of the device.

Growing community of inventors

Icheon-si, South Korea

Ju Yeab Lee