Semiconductor Energy Laboratory Co., Ltd.

Kosei Noda

Shunpei Yamazaki

Masashi Tsubuku

Toshinari Sasaki

Jun Koyama

Yuta Endo

Hideaki Kuwabara

Kouhei Toyotaka

Hiroyuki Miyake

Hiroki Ohara

Kei Takahashi

Atsushi Hirose

Mizuho Sato

Junichiro Sakata

Kazunori Watanabe

Hitomi Sato

Hikaru Harada

Yoshiaki Oikawa

Atsuo Isobe

Yuichi Sato

Yuhei Sato

Ryo Arasawa

Masayuki Sakakura

Mitsuhiro Ichijo

Miyuki Hosoba

Yutaka Okazaki

Keitaro Imai

Hotaka Maruyama

Toshiya Endo

Kazuki Tanemura

Noriyoshi Suzuki

Masumi Nomura

Mai Sugikawa

Mizuho Ikarashi

Tadashi Nakano

Tatsuya Honda

Satoshi Toriumi

Toshihiko Takeuchi

Yukie Suzuki

Suzunosuke Hiraishi

Yusuke Sekine

Hiroyuki Tomatsu

Nanae Sato

Yoshiyuki Kurokawa

Toru Takayama

Kengo Akimoto

Takayuki Ikeda

Hideto Ohnuma

Akihisa Shimomura

Kensuke Yoshizumi

Tetsuhiro Tanaka

Kazutaka Kuriki

Takashi Hamada

Nobuhiro Inoue

Tatsuji Nishijima

Seiji Yasumoto

Kosei Nei

Masaki Koyama

Toshiyuki Miyamoto

Daigo Ito

Makoto Ishikawa

Kenichiro Makino

Takayuki Saito

Noriko Harima

Kazuko Yamawaki

Noriko Matsumoto

An object is to reduce leakage current and parasitic capacitance of a transistor used for an LSI, a CPU, or a memory. A semiconductor integrated circuit such as an LSI, a CPU, or a memory is manufactured using a thin film transistor in which a channel formation region is formed using an oxide semiconductor which becomes an intrinsic or substantially intrinsic semiconductor by removing impurities which serve as electron donors (donors) from the oxide semiconductor and has larger energy gap than that of a silicon semiconductor. With use of a thin film transistor using a highly purified oxide semiconductor layer with sufficiently reduced hydrogen concentration, a semiconductor device with low power consumption due to leakage current can be realized.

Semiconductor device and manufacturing method thereof

To reduce a leakage current of a transistor so that malfunction of a logic circuit can be suppressed. The logic circuit includes a transistor which includes an oxide semiconductor layer having a function of a channel formation layer and in which an off current is 1×10A or less per micrometer in channel width. A first signal, a second signal, and a third signal that is a clock signal are input as input signals. A fourth signal and a fifth signal whose voltage states are set in accordance with the first to third signals which have been input are output as output signals.

Logic circuit and semiconductor device

An object is to obtain a semiconductor device having a high sensitivity in detecting signals and a wide dynamic range, using a thin film transistor in which an oxide semiconductor layer is used. An analog circuit is formed with the use of a thin film transistor including an oxide semiconductor which has a function as a channel formation layer, has a hydrogen concentration of 5×10atoms/cmor lower, and substantially functions as an insulator in the state where no electric field is generated. Thus, a semiconductor device having a high sensitivity in detecting signals and a wide dynamic range can be obtained.

Analog circuit and semiconductor device

An object is to provide a semiconductor device having a structure with which parasitic capacitance between wirings can be sufficiently reduced. An oxide insulating layer serving as a channel protective layer is formed over part of an oxide semiconductor layer overlapping with a gate electrode layer. In the same step as formation of the oxide insulating layer, an oxide insulating layer covering a peripheral portion of the oxide semiconductor layer is formed. The oxide insulating layer which covers the peripheral portion of the oxide semiconductor layer is provided to increase the distance between the gate electrode layer and a wiring layer formed above or in the periphery of the gate electrode layer, whereby parasitic capacitance is reduced.

Semiconductor device

A logic circuit includes a thin film transistor having a channel formation region formed using an oxide semiconductor, and a capacitor having terminals one of which is brought into a floating state by turning off the thin film transistor. The oxide semiconductor has a hydrogen concentration of 5×10(atoms/cm) or less and thus substantially serves as an insulator in a state where an electric field is not generated. Therefore, off-state current of a thin film transistor can be reduced, leading to suppressing the leakage of electric charge stored in a capacitor, through the thin film transistor. Accordingly, a malfunction of the logic circuit can be prevented. Further, the excessive amount of current which flows in the logic circuit can be reduced through the reduction of off-state current of the thin film transistor, resulting in low power consumption of the logic circuit.

A semiconductor device with stable electrical characteristics is provided. Alternatively, a semiconductor device having normally-off electrical characteristics is provided. A semiconductor device includes a gate electrode, a gate insulator, and an oxide semiconductor, the oxide semiconductor contains fluorine in a channel formation region, and a fluorine concentration in the channel formation region is higher than or equal to 1×10atoms/cmand lower than or equal to 1×10atoms/cm. Note that fluorine is added by an ion implantation method.

Semiconductor device, method for manufacturing semiconductor device, module, and electronic device

A highly reliable semiconductor device which includes a thin film transistor having stable electric characteristics, and a manufacturing method thereof. In the manufacturing method of the semiconductor device which includes a thin film transistor where a semiconductor layer including a channel formation region is an oxide semiconductor layer, heat treatment which reduces impurities such as moisture to improve the purity of the oxide semiconductor layer and oxidize the oxide semiconductor layer (heat treatment for dehydration or dehydrogenation) is performed. Not only impurities such as moisture in the oxide semiconductor layer but also those existing in a gate insulating layer are reduced, and impurities such as moisture existing in interfaces between the oxide semiconductor layer and films provided over and under and in contact with the oxide semiconductor layer are reduced.

Method for manufacturing semiconductor device

To reduce a leakage current of a transistor so that malfunction of a logic circuit can be suppressed. The logic circuit includes a transistor which includes an oxide semiconductor layer having a function of a channel formation layer and in which an off current is 1&#xd7;10A or less per micrometer in channel width. A first signal, a second signal, and a third signal that is a clock signal are input as input signals. A fourth signal and a fifth signal whose voltage states are set in accordance with the first to third signals which have been input are output as output signals.

A logic circuit includes a thin film transistor having a channel formation region formed using an oxide semiconductor, and a capacitor having terminals one of which is brought into a floating state by turning off the thin film transistor. The oxide semiconductor has a hydrogen concentration of 5&#xd7;10(atoms/cm) or less and thus substantially serves as an insulator in a state where an electric field is not generated. Therefore, off-state current of a thin film transistor can be reduced, leading to suppressing the leakage of electric charge stored in a capacitor, through the thin film transistor. Accordingly, a malfunction of the logic circuit can be prevented. Further, the excessive amount of current which flows in the logic circuit can be reduced through the reduction of off-state current of the thin film transistor, resulting in low power consumption of the logic circuit.

Semiconductor device including transistor

A semiconductor device is manufactured using a transistor in which an oxide semiconductor is included in a channel region and variation in electric characteristics due to a short-channel effect is less likely to be caused. The semiconductor device includes an oxide semiconductor film having a pair of oxynitride semiconductor regions including nitrogen and an oxide semiconductor region sandwiched between the pair of oxynitride semiconductor regions, a gate insulating film, and a gate electrode provided over the oxide semiconductor region with the gate insulating film positioned therebetween. Here, the pair of oxynitride semiconductor regions serves as a source region and a drain region of the transistor, and the oxide semiconductor region serves as the channel region of the transistor.

Semiconductor device and method for manufacturing the same

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Kanagawa, Japan

Kosei Noda