Abstract: A process of forming a nitride semiconductor device is disclosed. The process includes steps of (a) implanting impurities into a portion of nitride semiconductor layers epitaxially grown on a substrate; (b) forming a silicon nitride (SiN) film on the nitride semiconductor layers; and (c) annealing the nitride semiconductor layers for activating the implanted impurities as covering the nitride semiconductor layers by the SiN film. The process has a feature that the SiN film shows, in a Fourier Transformation Infrared (FT-IR) spectroscopy measured before the step of annealing, absorbance peaks attributed to translational motions of a Si—H bond and an N—H bond at most 1/30 of an absorbance peak attributed to a SiN bond.

Abstract: A process of forming a semiconductor device type of high electron-mobility transistor (HEMT) made of nitride semiconductor materials, and a HEMT formed thereby are disclosed. The process includes steps of implanting impurities into regions corresponding to n+ regions, activating the impurities by annealing, removing a disarranged region between the n+ regions, and forming the gate electrode onto the region where the disarranged region is removed in advance to the formation. The annealing, even when an insulating film covers the surface, causes the disarranged region primarily due to the sublimation of nitrogen (N). When the gate electrode is formed on the disarranged region, leak currents between the electrodes become substantial. Contrary, the HEMT of the invention provides the gate electrode onto a surface where the disarranged region is removed.

Abstract: A process of forming a nitride semiconductor device is disclosed. The process includes steps of (a) implanting impurities into a portion of nitride semiconductor layers epitaxially grown on a substrate; (b) forming a silicon nitride (SiN) film on the nitride semiconductor layers; and (c) annealing the nitride semiconductor layers for activating the implanted impurities as covering the nitride semiconductor layers by the SiN film. The process has a feature that the SiN film shows, in a Fourier Transformation Infrared (FT-IR) spectroscopy measured before the step of annealing, absorbance peaks attributed to translational motions of a Si—H bond and an N—H bond at most 1/30 of an absorbance peak attributed to a SiN bond.

Abstract: A method for manufacturing a semiconductor device includes: forming a first active region, a second active region, an inactive region located between the first active region and the second active region, and a third active region, which crosses the inactive region to electrically connect the first active region to the second active region, in a semiconductor layer; forming an insulating layer on the semiconductor layer; and forming an opening selectively in the insulating layer by dry etching.

Abstract: A method for manufacturing a semiconductor device includes: forming a first active region, a second active region, an inactive region located between the first active region and the second active region, and a third active region, which crosses the inactive region to electrically connect the first active region to the second active region, in a semiconductor layer; forming an insulating layer on the semiconductor layer; and forming an opening selectively in the insulating layer by dry etching.

Abstract: A method for manufacturing a semiconductor device includes: forming a first active region, a second active region, an inactive region located between the first active region and the second active region, and a third active region, which crosses the inactive region to electrically connect the first active region to the second active region, in a semiconductor layer; forming an insulating layer on the semiconductor layer; and forming an opening selectively in the insulating layer by dry etching.

Abstract: A method for fabricating a semiconductor device includes forming a recess to an AlGaN layer by etching, the AlGaN layer having an Al composition ratio of 0.2 or greater, the recess having a bottom having an RMS roughness less than 0.3 nm, forming a first Ta layer having a thickness of 4 nm to 8 nm on the bottom of the recess, and annealing the first Ta layer to make an ohmic contact in the AlGaN layer.

Abstract: A method for fabricating a semiconductor device includes forming a recess to an AlGaN layer by etching, the AlGaN layer having an Al composition ratio of 0.2 or greater, the recess having a bottom having an RMS roughness less than 0.3 nm, forming a first Ta layer having a thickness of 4 nm to 8 nm on the bottom of the recess, and annealing the first Ta layer to make an ohmic contact in the AlGaN layer.

Abstract: A multi-beam photoelectric sensor (10) includes a light emitter and a photo detector each having an elongate casing (13). At least one of opposite lengthwise ends of the casing (13) is configured to receive a cable (53) for electric coupling. The casing (13) has a mount (20) located around its back surface within the length of the casing (13) to fix the casing (13) to an external structure.

Abstract: A multi-beam photoelectric sensor (10) includes a light emitter and a photo detector each having an elongate casing (13). At least one of opposite lengthwise ends of the casing (13) is configured to receive a cable (53) for electric coupling. The casing (13) has a mount (20) located around its back surface within the length of the casing (13) to fix the casing (13) to an external structure.

Abstract: A biodegradable plastic composition, which may be in the form of a molded dy, includes gelatinized starch and a biodegradable, aliphatic polyester resin having a melting point of 45.degree.-130 .degree. C. The plastic is produced by kneading a blend containing a starchy substance selected from non-gelatinized, granular starch and gelatinized starch and the aliphatic polyester resin at a temperature higher than the melting point of the aliphatic polyester in the presence of water in an amount of 1-45 % based on the weight of the starchy substance.

Abstract: A biodecomposable or biodisintegrable moldable material which comprises a mixture of 10-70 vol. % of a natural high molecular substance, 30-70 vol. % of a thermoplastic resin and 0-45 vol. % of a filler.

Abstract: A thermal head recording device includes a thermal head adapted to print a sheet, a source of information alternately producing coded image signal having an arbitrary length and coded EOL signal, decoder for decoding the coded image signal and coded EOL signal into image signal having a predetermined length and EOL signal, respectively. The image signal is transmitted to the thermal head in response to a driving pulse produced from driving pulse generator.