Method of manufacturing a semiconductor device

Claim 2

A semiconductor device comprising a lateral transistor and a vertical transistor, wherein the vertical transistor comprises distributed base regions having an area as required for transistor action, a buried insulating film which surrounds the respective base regions in such a manner as to isolate them from one another, a conductive layer on the buried insulating film connecting the base regions,a base connection; provided at a part of the conductive layer, and collector connections formed respectively on the distributed base regions.

Claim 3

A semiconductor device as claimed in claim 1, wherein the lateral transistor comprises: an emitter region and a collector region of the same conductivity type as the vertical transistor base region, the facing area between those emitter and collector regions being limited to that required for transistor action, wherein the buried insulating film is provided adjacent to the emitter region and collector region of the lateral transistor and provides insulation between either the emitter region or the collector region and that base region of the vertical transistor adjacent thereto, and wherein the conductive layer provided on the buried insulating film connects that base region and the adjacent collector or emitter region of the lateral transistor, adjacent to 'the buried insulating film.

Claim 4

A semiconductor device comprising a lateral transistor and a vertical transistor, characterised by a semiconductor layer of one conductivity type, , a thick oxide film formed selectively on the semiconductor layer, a part of said semiconductor layer being exposed by removing a portion of the thick oxide film, an impurity region of the opposite conductivity type (opposite to the said one conductivity type) forming one junction.of the lateral transistor being formed by introducing impurity into the exposed part of the semiconductor layer, an impurity region of the opposite conductivity type in contact with an active base region of the vertical transistor, and a, conductive layer partly provided on the thick oxide film and in contact with the said impurity regions to connect said impurity regions.

Claim 5

A semiconductor device comprising a lateral transistor and a vertical transistor, characterised by a semiconductor layer of one conductivity type, , a thick oxide film formed selectively on the semiconductor layer, a part of said semiconductor layer being exposed by removing a portion of the thick oxide film, an impurity region of the opposite conductivity type (opposite to the said one conductivity type) forming one junction.of the lateral transistor being formed by introducing impurity into the exposed part of the semiconductor layer, an impurity region of the opposite conductivity type in contact with an active base region of the vertical transistor, and a, conductive layer partly provided on the thick oxide film and in contact with the said impurity regions to connect said impurity regions.

Claim 6

A semiconductor device comprising: a semiconductor substrate of one conductivity type, a plurality of rectangular mesa type regions formed on one surface of the semiconductor substrate, a buried insulating film formed on the semiconductor substrate in such a manner as to surround the mesa type regions, portions on opposite sides of each of the rectangular mesa type regions being exposed, emitter and collector regions of a lateral transistor being formed by the introduction of impurity of the opposite conductivity type (opposite to the said one conductivity type) into the exposed portions of one rectangular mesa type region, a base contact region for the base region of a vertical transistor being formed by introducing impurity into the exposed portion of another mesa type region adjacent to the mesa type region wherein the emitter region and the collector region of the lateral transistor are formed, a conductor layer connecting the said base contact region and the collector region of the lateral transistor, a base region of the vertical transistor being of the same conductivity type as the said base contact region, a collector connection for the vertical transistor being formedon the said base region, and a base connection for the said base region being established by a conductor.

Claim 7

A semiconductor device comprising: a semiconductor substrate of one conductivity type, a plurality of rectangular mesa type regions formed on one surface of the semiconductor substrate, a buried insulating film formed on the semiconductor substrate in such a manner as to surround the mesa type regions, portions on opposite sides of each of the rectangular mesa type regions being exposed, emitter and collector regions of a lateral transistor being formed by the introduction of impurity of the opposite conductivity type (opposite to the said one conductivity type) into the exposed portions of one rectangular mesa type region, a base contact region for the base region of a vertical transistor being formed by introducing impurity into the exposed portion of another mesa type region adjacent to the mesa type region wherein the emitter region and the collector region of the lateral transistor are formed, a conductor layer connecting the said base contact region and the collector region of the lateral transistor, a base region of the vertical transistor being of the same conductivity type as the said base contact region, a collector connection for the vertical transistor being formedon the said base region, and a base connection for the said base region being established by a conductor.