Semiconductor Energy Laboratory Co., Ltd.

Yukiko Uehara

Toshimitsu Konuma

Akira Sugawara

Yasuhiko Takemura

Hongyong Zhang

Hideki Uochi

Hideomi Suzawa

Hideto Ohnuma

Naoaki Yamaguchi

Atsunori Suzuki

Shunpei Yamazaki

Mitsunori Sakama

Takeshi Fukada

Hiroshi Uehara

Minoru Miyazaki

Akane Murakami

Takeshi Nishi

Satoshi Murakami

Misako Nakazawa

Itaru Koyama

A TFT formed on an insulating substrate source, drain and channel regions, a gate insulating film formed on at least the channel region and a gate electrode formed on the gate insulating film. Between the channel region and the drain region, a region having a higher resistivity is provided in order to reduce an Ioff current. A method for forming this structure comprises the steps of anodizing the gate electrode to form a porous anodic oxide film on the side of the gate electrode; removing a portion of the gate insulating using the porous anodic oxide film as a mask so that the gate insulating film extends beyond the gate electrode but does not completely cover the source and drain regions. Thereafter, an ion doping of one conductivity element is performed. The high resistivity region is defined under the gate insulating film.

Semiconductor device including transistors with silicided impurity regions

Semiconductor device and method for manufacturing the same

Semiconductor device having pixel electrode and peripheral circuit

A silicon oxide film is formed to cover an island non-monocrystalline silicon region by plasma CVD using an organic silane having ethoxy groups (e.g., TEOS) and oxygen as raw materials, while hydrogen chloride or a chlorine-containing hydrocarbon (e.g., trichloroethylene) of a fluorine-containing gas is added to the plasma CVD atmosphere, preferably in an amount of from 0.01 to 1 mol % of the atmosphere so as to reduce the alkali elements from the silicon oxide film formed and to improve the reliability of the film. Prior to forming the silicon oxide film, the silicon region may be treated in a plasma atmosphere containing oxygen and hydrogen chloride or a chlorine-containing hydrocarbon. The silicon oxide film is obtained at low temperatures and this has high reliability usable as a gate-insulating film in a semiconductor device.

Insulating film and method of producing semiconductor device

A TFT formed on an insulating substrate source, drain and channel regions, a gate insulating film formed on at least the channel region and a gate electrode formed on the gate insulating film. Between the channel region and the drain region, a region having a higher resistivity is provided in order to reduce an loff current. A method for forming this structure comprises the steps of anodizing the gate electrode to form a porous anodic oxide film on the side of the gate electrode; removing a portion of the gate insulating using the porous anodic oxide film as a mask so that the gate insulating film extends beyond the gate electrode but does not completely cover the source and drain regions. Thereafter, an ion doping of one conductivity element is performed. The high resistivity region is defined under the gate insulating film.

Insulating film formed using an organic silane and method of producing

An alumina film, a silicon oxide film, and a silicon nitride film formed on a substrate containing a large amount of alumina are etched by using an etching material in which the concentration of ammonium fluoride, which is a component of BHF, is set low. Etching is performed by using an etching material that is an aqueous solution produced by mixing hydrofluoric acid, ammonium fluoride and water at a weight ratio of x:y:(100-x-y) where x and y satisfy a relationship y&lt;-2x+10 (0&lt;x.ltoreq.5, 0&lt;y.ltoreq.10). 50% hydrofluoric acid on the market and 40% aqueous solution of ammonium fluoride are used.

Etching material and etching method

An etching material comprising at least phosphoric acid, acetic acid, and nitric acid, with chromic acid added therein. Also claimed is an etching process using the etching material above, provided that the process comprises selectively etching, by using the solution, an aluminum oxide layer formed on the surface of a material containing aluminum as the principal component thereof.

Etching material and etching process

In an active matrix type liquid crystal electro-optical device using thin-film transistors, a metal film is formed on a transparent electrode that is opposed to the thin-film transistors. The metal film is oxidized by anode oxidation method using the electrode as an anode, to form a metal oxide film that serves as a short circuit preventing film. Alternatively, after a grid-shaped mask is formed on the metal film, the metal film is oxidized using the electrode as an anode, the mask is removed, and the metal film is again anode-oxidized, to form a non-oxidized portion. Thus, transparent and opaque regions, i.e., a black matrix is formed.

Short circuit preventing film of liquid crystal electro-optical device

A process for fabricating an electronic circuit by oxidizing the surroundings of a metallic interconnection such as of aluminum, tantalum, and titanium, wherein anodic oxidation is effected at a temperature not higher than room temperature, preferably, at 10.degree. C. or lower, and more preferably, at 0.degree. C. or lower. The surface oxidation rate of a metallic interconnection can be maintained constant to provide a surface free of irregularities.

Process for fabricating electronic circuits with anodically oxidized

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Kanagawa, Japan

Yukiko Uehara