Hitachi, Ltd.

Kazuo Hoya

Isao Yoshida

Isao Shimizu

Takeaki Okabe

Noboru Horie

Masatoshi Kimura

Kouzou Sakamoto

Shigeo Ohtaka

Toyomasa Koda

Kouichiro Satonaka

A method of fabricating semiconductor devices which include vertical elements and control elements. A well is formed by etching in a semiconductor substrate of a first conductivity type, and a first epitaxial layer having a second conductivity type opposite to the first conductivity type is epitaxially grown, followed by etching and/or grinding and/or polishing to fill said well. Further, a second epitaxial layer of the first conductivity type is epitaxially grown on the substrate and on the first epitaxial layer, and an impurity-doped layer of the second conductivity type for isolation is formed in the second epitaxial layer to penetrate therethrough. A first element is formed in the second epitaxial layer in a portion that corresponds to the well, and a second element having a vertical structure and having a current capability higher than that of the first element is formed except a portion of the second epitaxial layer that corresponds to the well.

Method of fabricating semiconductor devices which include vertical

Disclosed is a pressure sensor having a diaphragm formed in a semiconductor body, the diaphragm having at least one pair of pressure sensing semiconductor strips in a major surface thereof. One end of each of the strips is connected to each other by a semiconductor region. The semiconductor region is formed in a direction of small piezoresistive coefficients, and the strips are formed in a direction of great piezoresistive coefficients. Also, the region has a smaller resistance than the resistance of the strips. Also, electrode lead-out regions are provided at the other ends of the strips, which regions have low resistance, extend in a direction of small piezoresistive coefficients, and extend beyond the edge of the diaphram so the electrodes contact the semiconductor body outside the diaphragm. According to the present invention, a pressure sensor of high sensitivity and high precision can be provided.

Pressure sensor

A multiple transistor consists of vertical and lateral transistors, the collector region of the lateral transistor is formed by diffusion within the diffused base region of the vertical transistor simultaneously with the emitter region of the vertical transistor, into a structure in which the base of the vertical transistor and the collector of the lateral transistor are short-circuited. As a result the current gain of the lateral transistor can be varied by changing the area of the collector region.

Integrated multiple transistors with different current gains

Growing community of inventors

Tamamura, Japan

Kazuo Hoya