Abstract: A semiconductor device provided with a wide and shallow first groove and a second groove in the first groove area, having a narrower width than that of the first groove around a predetermined area in a one-conductive area provided in the upper region of a semiconductor substrate as a mesa groove, wherein at least the second groove is covered with an electrical insulator. The upper surface of the electrical insulator is located approximately as high as or lower than the upper surface of the electrical insulating film. Thus, especially in a mesa semiconductor device with a high-voltage resistance, an insulating protective layer having a sufficient thickness can be formed stably over the entire region of a mesa groove. As a result, the variation in high-voltage resistance characteristics can be decreased and the processing yield affected by breakage or cracking in the mesa groove region during subsequent processes caused by the formation of the mesa groove can be improved greatly.

Abstract: A semiconductor device includes on a semiconductor substrate an output transistor which is composed of a collector region, a first base region and a first emitter region, and a temperature detection transistor composed of the collector region, a second base region and a second emitter region. The output transistor is provided at a center of the collector region of the semiconductor substrate. A vacant region is formed on a center of the output transistor, and the temperature detection transistor is provided in the vacant region.

Abstract: A semiconductor device includes on a semiconductor substrate an output transistor which is composed of a collector region, a first base region and a first emitter region, and a temperature detection transistor composed of the collector region, a second base region and a second emitter region. The output transistor is provided at a center of the collector region of the semiconductor substrate. A vacant region is formed on a center of the output transistor, and the temperature detection transistor is provided in the vacant region.

Abstract: There is disclosed a semiconductor device having an electrode for wire bonding, comprising a first aluminum layer, a nickel-aluminum alloy layer, and a second aluminum layer. The electrode is suitable for bonding with copper wire, since the electrode withstands a wide range of bonding conditions--mechanical pressure, ultrasonic wave power and such, and permits a reliable electrical connection to be maintained.