Kioxia Corporation

Masayoshi Iwayama

Daisuke Watanabe

Toshihiko Nagase

Tadashi Kai

Masahiko Nakayama

Yosuke Kobayashi

Tatsuya Kishi

According to one embodiment, a memory device includes first and second wiring lines, memory cells between the first and second wiring lines, each includes a resistance change memory element and a switching element, and a determination operation control circuit configured to acquire a determination target voltage, acquire a reference voltage, and determine, based on a voltage difference between the determination target voltage and the reference voltage, a determination target resistance state that was set in the resistance change memory element. The determination target voltage acquisition time point and the reference voltage acquisition time point vary according to the selected memory cell.

Memory device determining target resistance states

According to one embodiment, a magnetic memory device includes a memory cell including a magnetoresistance effect element, a switching element, and a resistance element connected in series. The resistance element has an asymmetric current-voltage characteristic, and when data is read from the memory cell, a first voltage in a reverse direction is applied to the resistance element, and a resistance value of the resistance element at a time when the first voltage is applied is greater than a resistance value of the resistance element at a time when a second voltage in a forward direction having an absolute value identical to an absolute value of the first voltage is applied.

Magnetic memory device

A magnetic memory device including a first memory cell which includes a first stacked structure including a magnetic layer and a second memory cell which is provided on the first memory cell and includes a second stacked structure including a magnetic layer. Each of the first stacked structure and the second stacked structure includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer. A concentration of iron (Fe) contained in the first magnetic layer included in the first stacked structure and a concentration of iron (Fe) contained in the first magnetic layer included in the second stacked structure are different from each other.

A magnetic memory device includes a first interconnect, a second interconnect, a memory cell, and a write circuit. The memory cell is electrically coupled between the first interconnect and the second interconnect, and includes a variable resistance element and a switching element. The write circuit supplies a write voltage from the current source circuit or the voltage source circuit to write data into the memory cell. The write circuit supplies the write voltage to one of the first interconnect and the second interconnect using the voltage source circuit during a first period ranging from a first time to a second time. The write circuit supplies the write voltage to one of the first interconnect and the second interconnect using the current source circuit during a second period ranging from a third time to a fourth time.

According to one embodiment, a magnetic memory device includes a first memory cell and a control circuit. The first memory cell includes a first magnetoresistance effect element and a first switching element coupled in series. The control circuit is configured to repeatedly apply a first voltage to the first memory cell until a first condition is satisfied in a first operation.

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Seoul, South Korea

Masayoshi Iwayama