Sony Corporation

Seiichi Fukuda

Seiji Samukawa

Tetsuya Tatsumi

A plasma surface treatment system for irradiating a surface of a substrate to be treated with a nitrogen plasma excited by a high-frequency electric field to introduce nitrogen into the surface of the substrate comprises a pulse modulator for pulse modulation of the high-frequency electric field. By applying the high-frequency electric field in a pulsed form, it is possible to realize a nitriding by which the peak of nitrogen concentration is located at a shallower position and a desired nitrogen concentration can be obtained.

Plasma surface treatment system and plasma surface treatment method

A dry etching method and a method of manufacturing a semiconductor apparatus are disclosed with which satisfactory shape controllability can be obtained and a gate electrode formed by laminating tungsten can be formed without any breakage of a gate insulating film. A polysilicon film, a reaction barrier film made of tungsten nitride, a tungsten film and an offset film made of silicon nitride are sequentially formed on a gate insulating film. Then, a photoresist is used as a mask to etch the tungsten film. The etching process is performed by mixed gas of fluorine gas, chlorine, oxygen and nitrogen.

Dry etching method and method of manufacturing semiconductor apparatus

An object of this invention is to provide a dry etching method enabling a higher productivity and a higher yield without giving any bad effect to a substrate (such as, for instance, damages to a gate oxide film bed) even in a case where a side wall protection film is formed and then the side wall protection film must be removed later. This invention is a dry etching method for processing a polycide layer, in which a poly Si layer and a refractory metal silicide layer are formed in this order on an oxide film bed, by etching resist patterns selectively formed on said polycide layer into a mask, wherein the undercut 6 is provided in the refractory metal silicide layer 2 or other layers contacting the resist pattern 1 and then the refractory metal silicide layer 2 and the poly Si layer 3 are isotropically etched.

Dry etching method

A method for processing a layer of a silicon-based material on a wafer by which a sidewall protective film may be removed sufficiently and efficiently. An etching gas capable of yielding chlorine- or bromine-based chemical species and oxygen-based chemical species is used for dry etching a polycide film formed on a gate insulating film, plasma processing with an oxygen-based gas is then carried out for ashing the resist mask and removing carbonaceous components in the sidewall protective film. In addition, the sidewall protective film is oxidized so that the composition to that of stoichiometrically stable SiO.sub.2 is approached. Subsequently, the modified sidewall protective film is removed by processing with a dilute hydrofluoric acid solution. Since this sufficiently removes the sidewall protective film, it becomes possible to reduce the amount of dust and to improve coverage of a film to be formed by the next step. In this manner, a semiconductor device may be prepared with improved reliability and production yield.

Growing community of inventors

Kanagawa, Japan

Seiichi Fukuda