Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An anodic oxide containing impurities at a low concentration and thereby improved in film quality, and a process for fabricating the same. The process comprises increasing the current between a metallic thin film and a cathode until a voltage therebetween reaches a predetermined value, and maintaining the voltage at the predetermined value thereafter.

Abstract: 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.

Abstract: An anodic oxide containing impurities at a low concentration and thereby improved in film quality, and a process for fabricating the same. The process comprises increasing the current between a metallic thin film and a cathode until a voltage therebetween reaches a predetermined value, and maintaining the voltage at the predetermined value thereafter.

Abstract: A thin film transistor according to this invention has a gate electrode comprising a lower layer of aluminum of a high purity of over 99.5% and an upper layer of aluminum containing over 0.5% silicon. Alternatively, it has a gate electrode made by adding a IIIa group element to a IIIb group element. Residues produced by the etching of the silicon-containing aluminum gate electrode are etched with a mixture solution of hydrofluoric acid, nitric acid and acetic acid. After contact holes have been formed in an interlayer insulating film, laser annealing is carried out, and metal electrodes are formed in the contact holes thereafter.