Semiconductor Energy Laboratory Co., Ltd.

Jellyfish Research Laboratories, Inc.

Maruwa Oil & Fat Co., Ltd.

Satoshi Shinohara

Shunpei Yamazaki

Masahiko Hayakawa

Daisuke Matsubayashi

Wataru Sekine

Junichi Koezuka

Hideto Ohnuma

Miki Suzuki

Hajime Kimura

Naoto Kusumoto

Atsuo Isobe

Hiromichi Godo

Yoshiaki Ito

Takuro Ohmaru

Takayuki Baba

Koji Kihira

Provided are a transistor which has electrical characteristics requisite for its purpose and uses an oxide semiconductor layer and a semiconductor device including the transistor. In the bottom-gate transistor in which at least a gate electrode layer, a gate insulating film, and the semiconductor layer are stacked in this order, an oxide semiconductor stacked layer including at least two oxide semiconductor layers whose energy gaps are different from each other is used as the semiconductor layer. Oxygen and/or a dopant may be added to the oxide semiconductor stacked layer.

Semiconductor device and manufacturing method thereof

This invention is intended to produce a novel functional material through solubilization and molecular weight reduction of a water-insoluble polymeric compound, such as a water-insoluble protein or water-insoluble polysaccharide, in a simple and efficient manner. This invention provides a method for producing a degradation product of a water-insoluble polymeric compound comprising the steps of: bringing a water-insoluble polymeric compound into contact with a solid acid catalyst, heating the resulting mixture, and recovering a supernatant; adding an aqueous medium to the solid acid catalyst after the supernatant is recovered, agitating and heating the resulting mixture, and recovering a supernatant; washing the solid acid catalyst with an aqueous medium and recovering a wash solution; mixing the recovered supernatant with the wash solution, so as to obtain a fraction that has not adsorbed to the solid acid catalyst; and eluting an adsorbed fraction from the solid acid catalyst and recovering an eluate, so as to obtain a fraction that has adsorbed to the solid acid catalyst.

Method for continuous production of degradation product of water-insoluble polymeric compound

A semiconductor device in which deterioration of electrical characteristics which becomes more noticeable as the transistor is miniaturized can be suppressed is provided. The semiconductor device includes an oxide semiconductor stack in which a first oxide semiconductor layer, a second oxide semiconductor layer, and a third oxide semiconductor layer are stacked in this order from the substrate side over a substrate; a source electrode layer and a drain electrode layer which are in contact with the oxide semiconductor stack; a gate insulating film over the oxide semiconductor stack, the source electrode layer, and the drain electrode layer; and a gate electrode layer over the gate insulating film. The first oxide semiconductor layer includes a first region. The gate insulating film includes a second region. When the thickness of the first region is Tand the thickness of the second region is T, T&#x2265;T.

Semiconductor device comprising oxide semiconductor film

Provided is a bottom-gate transistor including an oxide semiconductor, in which electric-field concentration which might occur in the vicinity of an end portion of a drain electrode layer (and the vicinity of an end portion of a source electrode layer) when a high gate voltage is applied to a gate electrode layer is reduced and degradation of switching characteristics is suppressed, so that the reliability is improved. The cross-sectional shape of an insulating layer which overlaps over a channel formation region is a tapered shape. The thickness of the insulating layer which overlaps over the channel formation region is 0.3 &#x3bc;m or less, preferably 5 nm or more and 0.1 &#x3bc;m or less. The taper angle &#x3b8; of a lower end portion of the cross-sectional shape of the insulating layer which overlaps over the channel formation region is 60&#xb0; or smaller, preferably 45&#xb0; or smaller, further preferably 30&#xb0; or smaller.

Semiconductor device and method for manufacturing the same

A semiconductor device is provided, which includes a single crystal semiconductor layer formed over an insulating surface and having a source region, a drain region, and a channel formation region, a gate insulating film covering the single crystal semiconductor layer and a gate electrode overlapping with the channel formation region with the gate insulating film interposed therebetween. In the semiconductor device, at least the drain region of the source and drain regions includes a first impurity region adjacent to the channel formation region and a second impurity region adjacent to the first impurity region. A maximum of an impurity concentration distribution in the first impurity region in a depth direction is closer to the insulating surface than a maximum of an impurity concentration distribution in the second impurity region in a depth direction.

Semiconductor device and method for manufacturing semiconductor device

A semiconductor device in which deterioration of electrical characteristics which becomes more noticeable as the transistor is miniaturized can be suppressed is provided. The semiconductor device includes an oxide semiconductor stack in which a first oxide semiconductor layer, a second oxide semiconductor layer, and a third oxide semiconductor layer are stacked in this order from the substrate side over a substrate; a source electrode layer and a drain electrode layer which are in contact with the oxide semiconductor stack; a gate insulating film over the oxide semiconductor stack, the source electrode layer, and the drain electrode layer; and a gate electrode layer over the gate insulating film. The first oxide semiconductor layer includes a first region. The gate insulating film includes a second region. When the thickness of the first region is Tand the thickness of the second region is T, T&#x2267;T.

Provided is a semiconductor device having a structure which can suppress a decrease in electrical characteristics, which becomes more significant with miniaturization. The semiconductor device includes a plurality of gate electrode layers separated from each other. One of the plurality of gate electrode layers includes a region which overlaps with a part of an oxide semiconductor layer, a part of a source electrode layer, and a part of a drain electrode layer. Another of the plurality of gate electrode layers overlaps with a part of an end portion of the oxide semiconductor layer. The length in the channel width direction of each of the source electrode layer and the drain electrode layer is shorter than that of the one of the plurality of gate electrode layers.

Growing community of inventors

Atsugi, Japan

Satoshi Shinohara