Abstract: A lateral semiconductor device has a semiconductor layer on an insulating layer on a semiconductor substrate. The semiconductor layer has a region of a first conduction type and a region of a second conduction type with a drift region therebetween. The drift region is provided by a region of the first conduction type and a region of the second conduction type. The first and second conduction type drift regions are so arranged that when a reverse voltage bias is applied across the first and second conduction type regions of the semiconductor layer, the second conduction type drift region has an excess of charge relative to the first conduction type drift region which varies substantially linearly from the end of the drift region towards the first conduction type region of the semiconductor layer to the end of the drift region towards the second conduction type region of the semiconductor layer.

Abstract: An electron emission film includes a matrix consisting essentially of amorphous carbon and fullerene-like structures consisting essentially of a two-dimensional network of six-membered carbon rings. The fullerene-like structures are dispersed in the matrix and partially project from the matrix. The weight ratio of amorphous carbon to the fullerene-like structures is about 50:50 to 5:95. Amorphous carbon contains nitrogen acting as a donor at a concentration of about 4×10−7 to 10 atom %.

Abstract: A semiconductor device comprises an active area with a voltage termination structure located adjacent to the active area at an edge portion of the device. The edge portion comprises a substrate region (12) of a first semiconductor type. The voltage termination structure comprises at least one first termination region (11) of a second semiconductor type, the or each first termination region having at least one of either second and third termination regions (11a, 11b) of third and fourth semiconductor types located at substantially opposing edges thereof. The second and third termination regions (11a, 11b) respectively have a higher semiconductor doping concentration than the edge portion substrate region (12) and a lower semiconductor doping concentration than the first termination region(s) (11).

Abstract: A semiconductor device comprises an active area with a voltage termination structure located adjacent to the active area at an edge portion of the device. The edge portion comprises a substrate region (23, 24) of a first semiconductor type, and the voltage termination structure comprises first and second layers (21 and 22) formed within the substrate region. The first and second layers (21 and 22) define regions each of a second semiconductor type.

Abstract: The operating characteristics of emitter-switched thyristors (1) are improved by the addition of a floating ohmic contact (14) over adjacent regions of n+ and p+ type (15,16). In a lateral device, the floating ohmic contact (14) and the adjacent regions of n+ and p+ type (15,16) are provided between the anode region (4) and the cathode region (8,9,10). The device has enhanced turn-on characteristics with a high breakdown voltage and high current density capabilities.

Abstract: A semiconductor device made of a lightly doped region of a first conductivity type has a well formed of a second conductivity type. The well extends to the surface of the device. First, second and third heavily doped regions of the first conductivity type are in the surface of the well. An electrode is fixed to the first heavily doped region of the first conductivity type. The third heavily doped region of the first conductivity type adjoins the lightly doped region of the first conductivity type. The first and second heavily doped regions of the first conductivity type are spaced apart from one another so that a portion of the well extends to the surface of the device therebetween. A first gate electrode is fixed via an insulating layer to a portion of the well extending between the first and second heavily doped regions. The first and third heavily doped regions of the first conductivity type are spaced apart from one another so that a portion of the well extends therebetween.