Patent ID: 7701006
Filing Date: 2010-04-20
Classification: H01L

Abstract:
1. A semiconductor device comprising: a semiconductor substrate of a first conductivity type and at least one first region of a second conductivity type located underneath a first major surface of said semiconductor device; an external reverse bias voltage is applied across said substrate of a first conductivity type and said first region of a second conductivity type; wherein at least one second region of a second conductivity type is formed underneath said first major surface, said second region of a second conductivity type is isolated from any one of said first region of a second conductivity type; under an external applied reverse bias voltage, at least one said second region of a second conductivity type has an undepleted neutral portion at an intermediate electrical potential and is surrounded by the depleted region of said substrate, wherein said intermediate electrical potential is between the potential of neutral portion of said substrate of a first conductivity type and the potential of first region of a second conductivity type; said second region of a second conductivity type with intermediate electrical potential is an initiation region of a low-voltage power supply; a low-voltage power supply is produced directly on two terminals, wherein one terminal is a contact to said initiation region and another terminal is a contact to any other neutral portion, or indirectly on two output terminals of a normally-off three-terminal semiconductor device, wherein one input terminal of said normally-off three-terminal semiconductor device is connected to said initiation region and another input terminal is in common with one of two output terminals of said normally-off three-terminal semiconductor device.