Kabushiki Kaisha Tokai Rika Denki Seisakusho

Yasuo Imaeda

Hitoshi Iwata

Koichi Jinkai

Kenichi Kinoshita

Tatsuya Ishida

Shigekazu Yasuda

A compact capacitance type acceleration sensor in which a mass portion having a plurality of movable electrodes are arranged in a recess portion formed on the surface of a p-type single crystal silicon base plate under the condition that the mass portion can be displaced. A plurality of stationary electrodes are arranged at a position opposed to the movable electrodes being separate from the movable electrodes. The mass portion is elastically supported by a support from the lower side and also elastically supported by four beams from the lateral side. Due to the above structure, the damping characteristic of the mass portion can be improved.

Method of manufacturing a capacitance type acceleration sensor

Capacitance type acceleration sensor

A bipolar transistor of the multi-emitter type which is provided with a large number of emitter diffusion layers formed in the two-dimensionally arranged state on a base diffusion layer of a substrate, a large number of emitter electrode films formed respectively correspondingly on the emitter diffusion layers, a base electrode film formed on the base diffusion layer, and a collector electrode film formed on the substrate, and the transistor is further provided with a wiring film commonly connected to the large number of emitter electrode films except at least one of the emitter electrode films.

Load current detecting device including a multi-emitter bipolar

An object of this invention is to make it possible to directly monitor a temperature of a transistor chip. According to the present invention, p.sup.- region is formed on a substrate of a p.sup.+ layer by epitaxial growth. A first n-type diffusion layer which is a base region, and a second n-type diffusion layer which forms a temperature detecting element are formed in the p.sup.- region. A first p.sup.+ diffusion layer which is an emitter region is formed in the first n-type diffusion layer, while a second p.sup.+ diffusion layer which forms the temperature detecting element is formed in the second n-type diffusion layer. The temperature detecting element is operated in the active region, so that a characteristic free from variations in collector potential is obtained for the base-emitter potential difference of the temperature detecting element and the temperature of the junction thereof. Owing to this characteristic, the temperature of the junction can be detected from the base-emitter potential difference of the temperature detecting element during operation of the transistor.

Bipolar transistor with temperature detecting terminal

A semiconductor silicon single-crystal substrate is used in which the crystallographic axes are inclined by a predetermined angle with respect to a normal to a thicknesswise face of the semiconductor silicon single-crystal substrate. A conductive-type epitaxial layer is grown on this semiconductor silicon single-crystal substrate to a predetermined thickness such that the direction of the crystallographic axes of the conductive-type epitaxial layer coincides with the direction of the crystallographic axes of the semiconductor silicon single-crystal substrate. Accordingly, since side surfaces of a cavity portion provided in the semiconductor silicon single-crystal substrate by the etching of the substrate, i.e., side walls of the semiconductor silicon single-crystal substrate provided respectively in the longitudinal direction of a diaphragm, are each formed at an angle of 90.degree. with respect to the thicknesswise lower surface of the conductive-type epitaxial layer. Accordingly, an ultra-compact pressure sensor is formed in which the dimensional accuracy of the diaphragm is high. In addition, when etching is performed, etching stops at the epitaxial layer. Namely, since the epitaxial layer acts as an etching stopper, the dimensional accuracy in the thickness of the diaphragm is excellent over an entire wafer region for forming the substrate, and the yield in the wafer state improves remarkably.

Pressure sensor apparatus and method of manufacturing wherein the

Bipolar transistor

A bipolar transistor of a multi-emitter construction comprises a base diffusion layer formed in a substrate, a number of emitter diffusion layers formed in the base diffusion layer and arranged in a two-dimensional pattern, a base electrode film formed on the base diffusion layer, the base electrode film having a branch connection portion of a mesh-like shape surrounding each group consisting of at least one of the emitter diffusion layers, the base electrode film also having a main connection portion connected to said branch connection portion, and emitter electrode films formed respectively on said emitter electrode layers.

Growing community of inventors

Aichi, Japan

Yasuo Imaeda