Semiconductor Energy Laboratory Co., Ltd.

Toshihiko Saito

Kiyoshi Kato

Atsuo Isobe

Jun Koyama

Shunpei Yamazaki

Junichi Koezuka

Shinya Sasagawa

Shuhei Nagatsuka

Kazuya Hanaoka

Takanori Matsuzaki

Toru Takayama

Junya Maruyama

Yuugo Goto

Motomu Kurata

Hiroki Inoue

Yumiko Ohno

Takahiko Ishizu

Hajime Tokunaga

Akihiro Ishizuka

Hideomi Suzawa

Yutaka Shionoiri

Hideki Uochi

Yuichi Sato

Yasuyuki Takahashi

Shinji Ohno

Takehisa Hatano

Sho Nagamatsu

Yuta Uemura

Tamae Takano

Masami Endo

Yuki Hata

Takehisa Sato

A novel memory device is provided. The memory device includes a plurality of memory cells, and one memory cell includes a first transistor and a second transistor. One of a source and a drain of the first transistor is electrically connected to a gate of the second transistor through a node SN. Data written through the first transistor is retained at the node SN. When an OS transistor is used as the first transistor, formation of a storage capacitor is not needed. A region with a low dielectric constant is provided outside the memory cell, whereby noise from the outside is reduced and stable operation is achieved.

Memory device and electronic device

Power consumption of a semiconductor device is reduced efficiently. The semiconductor device includes a power management unit, a cell array, and a peripheral circuit for driving the cell array. The cell array includes a word line, a bit line pair, a memory cell, and a backup circuit for backing up data in the memory cell. A row circuit and a column circuit are provided in a first power domain capable of power gating, and the cell array is provided in a second power domain capable of power gating. In the operation mode of a memory device, a plurality of low power consumption modes, which have lower power consumption than the standby mode, are set. The power management unit selects one from the plurality of low power consumption modes and performs control for bringing the memory device into the selected low power consumption mode.

Semiconductor device with reduced power consumption and operation method thereof, electronic component, and electronic device

At least one of a plurality of transistors which are highly integrated in an element is provided with a back gate without increasing the number of manufacturing steps. In an element including a plurality of transistors which are longitudinally stacked, at least a transistor in an upper portion includes a metal oxide having semiconductor characteristics, a same layer as a gate electrode of a transistor in a lower portion is provided to overlap with a channel formation region of the transistor in an upper portion, and part of the same layer as the gate electrode functions as a back gate of the transistor in an upper portion. The transistor in a lower portion which is covered with an insulating layer is subjected to planarization treatment, whereby the gate electrode is exposed and connected to a layer functioning as source and drain electrodes of the transistor in an upper portion.

Semiconductor device

A variable capacitor is formed from a pair of electrodes and a dielectric interposed between the electrodes over a substrate, and an external input is detected by changing capacitance of the variable capacitor by a physical or electrical force. Specifically, a variable capacitor and a sense amplifier are provided over the same substrate, and the sense amplifier reads the change of capacitance of the variable capacitor and transmits a signal in accordance with the input to a control circuit.

A semiconductor memory device includes a bit line; two or more word lines; and a memory cell including two or more sub memory cells that each include a transistor and a capacitor. One of a source and a drain of the transistor is connected to the bit line, the other of the source and the drain of the transistor is connected to the capacitor, a gate of the transistor is connected to one of the word lines, and each of the sub memory cells has a different capacitance of the capacitor.

Semiconductor memory device

A semiconductor device which includes an oxide semiconductor and has favorable electrical characteristics is provided. In the semiconductor device, an oxide semiconductor film and an insulating film are formed over a substrate. Side surfaces of the oxide semiconductor film are in contact with the insulating film. The oxide semiconductor film includes a channel formation region and regions containing a dopant between which the channel formation region is sandwiched. A gate insulating film is formed on and in contact with the oxide semiconductor film. A gate electrode with sidewall insulating films is formed over the gate insulating film. A source electrode and a drain electrode are formed in contact with the oxide semiconductor film and the insulating film.

Semiconductor device and manufacturing method thereof

A connection electrode for connecting a transistor including a semiconductor material other than an oxide semiconductor to a transistor including an oxide semiconductor material is smaller than an electrode of the transistor including a semiconductor material other than an oxide semiconductor that is connected to the connection electrode.

A pulse converter circuit includes a logic circuit to which a first signal is input and from which a second signal is output. The logic circuit includes a p-channel transistor which determines whether a voltage of the second signal is set to a first voltage depending on a voltage of the gate; and an n-channel transistor which determines whether the voltage of the second signal is set to a second voltage, which is higher than the first voltage, depending on a voltage of the gate. The p-channel transistor includes a semiconductor layer containing an element of a group 14. The n-channel transistor includes an oxide semiconductor layer.

Pulse converter circuit

To increase a storage capacity of a memory module per unit area, and to provide a memory module with low power consumption, a transistor formed using an oxide semiconductor film, a silicon carbide film, a gallium nitride film, or the like, which is highly purified and has a wide band gap of 2.5 eV or higher is used for a DRAM, so that a retention period of potentials in a capacitor can be extended. Further, a memory cell has n capacitors with different capacitances and the n capacitors are each connected to a corresponding one of n data lines, so that a variety of the storage capacitances can be obtained and multilevel data can be stored. The capacitors may be stacked for reducing the area of the memory cell.

An object is to provide a semiconductor device capable of accurate data retention even with a memory element including a depletion mode transistor. A gate terminal of a transistor for controlling input of a signal to a signal holding portion is negatively charged in advance. The connection to a power supply is physically broken, whereby negative charge is held at the gate terminal. Further, a capacitor having terminals one of which is electrically connected to the gate terminal of the transistor is provided, and thus switching operation of the transistor is controlled with the capacitor.

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Kanagawa, Japan

Toshihiko Saito