Abstract: A cellular insulated gate bipolar transistor ("IGBT") device employs increased concentration in the active region between spaced bases to a depth greater than the depth of the base regions. The implant dose which is the source of the increased concentration is about 3.5.times.10.sup.12 atoms per centimeter squared and is driven for about 10 hours at 1175.degree. C. Lifetime is reduced by an increased radiation dose to reduce switching loss without reducing breakdown voltage or increasing forward voltage drop above previous levels. The increased concentration region permits a reduction in the spacing between bases and provides a region of low localized bipolar gain, increasing the device latch current. The avalanche energy which the device can successfully absorb while turning off an inductive load is significantly increased. The very deep increased conduction region is formed before the body and source regions in a novel process for making the new junction pattern.

Abstract: A process for producing a radiation resistant power MOSFET is disclosed. The gate oxide is formed toward the end of the processing and is not exposed to substantial thermal cycling. The gate oxide thickness is increased to more than 1250 .ANG. for a device with a reverse voltage rating of 250 volts and the channel concentration is reduced to maintain a low threshold voltage. The thicker oxide prevents single event damage under reverse bias voltage.

Abstract: A cellular insulated gate bipolar transistor ("IGBT") device employs increased concentration in the active region between spaced bases to a depth greater than the depth of the base regions. The implant dose which is the source of the increased concentration is about 3.5.times.10.sup.12 atoms per centimeter squared and is driven for about 10 hours at 1175.degree. C. Lifetime is reduced by an increased radiation dose to reduce switching loss without reducing breakdown voltage or increasing forward voltage drop above previous levels. The increased concentration region permits a reduction in the spacing between bases and provides a region of low localized bipolar gain, increasing the device latch current. The avalanche energy which the device can successfully absorb while turning off an inductive load is significantly increased. The very deep increased conduction region is formed before the body and source regions in a novel process for making the new junction pattern.

Abstract: A layer of amorphous silicon covers the top surface of a semiconductor wafer to act as a moisture and contaminant barrier and to prevent the formation of aluminum hillocks on the aluminum bonding pads for the source and gate electrodes of a power MOSFET or other power semiconductor device. The amorphous silicon is easily penetrated by wire bonding apparatus used to make wire bonds to the conductor pads beneath the amorphous silicon.

Abstract: A polysilicon gate resistor consists of a plurality of parallel polysilicon strips extending from gate finger to gate pad. Different numbers of parallel strips can be selected during manufacture by using different contact masks.

Abstract: A layer of amorphous silicon covers the top surface of a semiconductor wafer to act as a moisture and contaminant barrier and to prevent the formation of aluminum hillocks on the aluminum bonding pads for the source and gate electrodes of a power MOSFET or other power semiconductor device. The amorphous silicon is easily penetrated by wire bonding apparatus used to make wire bonds to the conductor pads beneath the amorphous silicon.

Abstract: A process for producing a radiation resistant power MOSFET is disclosed. The gate oxide is formed toward the end of the processing and is not exposed to substantial thermal cycling. Arsenic doping is used in the early part of the process to form the source region, and diffused too slowly to be adversely affected by later thermal cycling process steps. The source region has a relatively high resistance to act as a ballasting resistor to prevent burnout of one of a large number of parallel connected cells.

Abstract: A process for producing a radiation resistant power MOSFET is disclosed. The gate oxide is formed toward the end of the processing and is not exposed to substantial thermal cycling. Arsenic doping is used in the early part of the process to form the source region, and diffused too slowly to be adversely affected by later thermal cycling process steps. The source region has a relatively high resistance to act as a ballasting resistor to prevent burnout of one of a large number of parallel connected cells.