Toshiba Memory Corporation

Kioxia Corporation

Toshiba Memeory Corporation

Sanad Bushnaq

Masanobu Shirakawa

Noriyasu Kumazaki

Masashi Yamaoka

Toshifumi Hashimoto

Hidehiro Shiga

Takayuki Akamine

Xu Li

Manabu Sato

According to one embodiment, a semiconductor storage device includes a first memory string including a first memory transistor, a first word line connected to a gate electrode of the first memory transistor, a source line connected to one end of the memory string, and a first connection transistor connected between the first word line and the source line.

Semiconductor storage device

A semiconductor memory device comprises a memory string that includes a plurality of memory cells electrically connected in series, the memory cells including first to fourth memory cells, first to fourth word lines that are electrically connected to gates of the first to fourth memory cells, respectively, a voltage generation circuit configured to generate a first voltage, a first circuit configured to output the first voltage to one of first and second wires, a second circuit configured to connect the first and second wires to the first and second word lines, respectively, and a third circuit configured to connect the first and second wires to the third and fourth word lines, respectively.

Semiconductor memory device

A semiconductor storage device comprises a memory block including first and second memory cells, first and second word lines electrically connected to the first and second memory cells, respectively, first and second booster circuits, and a control circuit. During a read operation in which the first word line is a selected word line, the control circuit controls the first booster circuit to start boosting the output voltage thereof before a target block address associated with the read command is determined, causes the output voltage of the first booster circuit to be supplied to the first and second word lines, controls the second booster circuit to start boosting the output voltage thereof, and causes the output voltage of the second booster circuit, instead of the output voltage of the first booster circuit, to be supplied to the first word line.

A semiconductor storage device includes a word line and a wiring, a first transistor controlled to connect the word line to the wiring, a first booster circuit configured to boost an output voltage thereof to a first voltage, a second transistor controlled to connect the first booster circuit to the wiring, and a control circuit configured to control the first booster circuit, and the first and second transistors during a read operation. During the read operation, the control circuit controls the first booster circuit to start boosting its output voltage to the first voltage while controlling the second transistor to connect the output of the first booster circuit to the wiring so that a voltage of the wiring rises together with the output voltage. After the output voltage has reached the first voltage, the control circuit controls the first transistor to connect the word line to the wiring.

According to one embodiment, A level shifter includes a first circuit configured to generate a first signal, the first signal being inverted and delayed signal of a second signal, a NAND circuit including a first input terminal and a second input terminal, the second signal being input to the first terminal, the first signal being input to the second terminal, a first transistor, a first voltage being applied to a first terminal of the first transistor, a second terminal of the first transistor being connected to a third input terminal of the NAND circuit, a third signal which inverts the second signal being applied to a gate of the first transistor, a second transistor, a second voltage being applied to a first terminal of the second transistor, the second voltage being higher than the first signal, a gate of the second transistor being connected to an output terminal, a third transistor, the second voltage being applied to a first terminal of the third transistor, a second terminal of the third transistor being connected to a second terminal of the second transistor, the second signal being applied to a gate of the third transistor, and a fourth transistor, a first terminal of the fourth transistor being connected to the second terminal of the third transistor, a second terminal of the fourth transistor being connected to the output terminal, an output terminal of the NAND circuit being connected to a gate of the fourth transistor.

Level shifter

A memory device includes a memory cell array including a plurality of memory cell groups, and a decoder circuit configured to control selection of the memory cell groups. The decoder circuit includes an address decoder circuit configured to activate the decoder circuit based on an input address, a plurality of information retention circuits, each of which corresponds to one of the memory cell groups and outputting a signal that indicates whether or not the corresponding memory cell group is defective, a transistor having a gate connected to each of the outputs of the information retention circuits, and a signal output circuit configured to output a control signal for selecting or not selecting the memory cell groups based on an on/off state of the transistor.

Memory device

A semiconductor memory device includes a first block of memory cells that includes a first word line above a substrate, a second word line above the first word line, and a third word line above the second word line, a first control line electrically connected to the first word line, a second control line electrically connected to the second word and between the first control line and the first block, and a third control line electrically connected to the third word line and between the second control line and the first block.

A semiconductor memory device includes: a first memory unit including first to fourth memory cells; a second memory unit including fifth to eighth memory cells; a first word line coupled to gates of the first and fifth memory cells; a second word line coupled to gates of the second and sixth memory cells; a third word line coupled to gates of the third and seventh memory cells; and a fourth word line coupled to gates of the fourth and eighth memory cells. In a write operation, writes to the fourth memory cell, the first memory cell, the eighth memory cell, and the fifth memory cell are executed in order.

Semiconductor memory device and memory system

A non-volatile semiconductor memory device includes a first memory cell above a substrate and electrically connected to a first word line, a second memory cell above the first memory cell and electrically connected to a second word line, and a controller. The controller is configured to execute a write operation that includes a first step in which a first voltage is applied to a selected word line and to a non-selected word line, a second step after the first step in which a program voltage is applied to the selected word line, and a third step after the second step in which a second voltage higher than the first voltage is applied to the non-selected word line. A time period between a start of the second step and a start of the third step is different depending on whether the first or second memory cell is being written.

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Yokohama Kanagawa, Japan

Sanad Bushnaq