Abstract: A gate turn-off thyristor is disclosed which includes a main thyristor having a shorted emitter structure on the anode side thereof and an auxiliary thyristor having a shorted emitter structure on the cathode side thereof and wherein the cathode of the auxiliary thyristor is connected to the gate of the main thyristor to on-off control a large current by a small gate signal.

Abstract: A light activated thyristor with high dv/dt capability is provided by disposing first and second thyristors, one a primary and the other a pilot thyristor, in a semiconductor body having first and second major surface. The two thyristors have common first emitter, first base, and second base regions, and have spaced apart second emitter regions adjoining the second major surface of the body. The second emitter region of the second thyristor consists of first and second portions, first portion abutting the second base region of the second thyristor to create a ratarded electrical field. An exposed portion of the second major surface at the second emitter region of the second thyristor activates the second thyristor when electromagnetic radiation of wavelengths corresponding substantially to the energy bandgap of the semiconductor body strikes this exposed portion.

Abstract: A novel structure of a high breakdown voltage semiconductor device has a pair of major surfaces on which a pair of main electrodes are formed and a PN junction formed between the pair of major surfaces with a side surface to which the PN junction is exposed being covered with a passivation material. An auxiliary electrode of a conductive member is provided, which is disposed externally of the peripheral edge of the major surface of the semiconductor substrate, and which contacts to the passivation material and is electrically connected to the main electrode. When a voltage for reverse biasing the PN junction is applied between the pair of main electrodes, ions in the passivation material are collected by an electric field established in the passivation material so that the deterioration of the breakdown on the surface of the semiconductor substrate is prevented.

Abstract: A main thyristor region is formed which comprises four continuous layers of alternately different conductivities consisting of first, second, third and fourth layers, PNPN for example. The main thyristor region constitutes a main thyristor section together with a couple of main electrodes in ohmic contact with the outside ones of the four layers. A pilot thyristor section and an auxiliary pilot thyristor section are constituted by employing the first, second and third layers of the main thyristor section and the main electrode in ohmic contact with the outside of the first layer and further by introducing fifth and sixth layers for forming PH junctions with the third layer. Further, there are provided a gate means for turning on the pilot thyristor section and an auxiliary gate means being in contact with the fifth or sixth layer.

Abstract: Disclosed is a bidirectional light-activated thyristor which comprises a first and a second thyristor portion arranged in inverse-parallel with each other with a predetermined positional relation, an isolation section for electrically isolating the first and second thyristor portions from each other, a first and a second main electrode for connecting the first and second thyristor portions with each other in inverse-parallel, and a first and a second photo-trigger means for triggering the first and second thyristor portions respectively, wherein the photo-trigger signal from the first photo-trigger means is prevented by the first thyristor portion from reaching the second thyristor portion and the photo-trigger signal from the second photo-trigger means is prevented by the second thyristor portion from reaching the first thyristor portion.

Abstract: A bidirectional light-activated thyristor is provided which has a first and a second thyristor portion arranged in inverse-parallel with each other with a predetermined positional relation. The first and second thyristor portions are electrically isolated from each other by an isolating section. The bidirectional light-activated thyristor is provided with a first and a second photo trigger means for triggering the first and second thyristor portions respectively. Means is further provided for blocking a photo-trigger signal from the first photo-trigger means to the second thyristor portion and from the second photo-trigger means to the first thyristor portion.

Abstract: A light emitting semiconductor device and a light detecting semiconductor device are coupled optically with each other through a light guide. The light guide is made of a single piece of light transmissible insulating material and at least its end portion associated with the semiconductor light detector is brought into wet contact with a light sensing region of the semiconductor light detector including its neighboring area. While being in fluid state, the light transmissible insulator held in wet contact with the semiconductor light emitter and detector is shaped into a predetermined configuration and thereafter hardened to form the light guide.

Abstract: A semiconductor controlled rectifying device comprising a semiconductor substrate having four layers of PNPN, a couple of main electrodes in ohmic contact with the outside ones of the four layers respectively, a gate electrode provided on the intermediate P layer, an N-type minor region formed in the intermediate P layer in the vicinity of the gate electrode, and a conductor in contact with part of the outside N layer and with the minor region and disposed along the outer periphery of the outside N layer on the intermediate P layer.

Abstract: A bidirectional photothyristor device comprises a semiconductive substrate including an NPNPN quintuple layer in which projections of both the outer layers Ns in the stacking direction are not overlapped so as to define two quadruple layer regions each having either one of the outer layers Ns as an end layer, a pair of main electrodes connecting the two quadruple layer regions in parallel relationship, a recess formed between the two quadruple layer regions within the semiconductive substrate and to which two intermediate P-N junctions are exposed, and means for applying a light trigger signal to the recess.

Abstract: A light-activated semiconductor-controlled rectifier apparatus has four layers of PNPN. The outer N-type layer comprises a first portion having a plurality of short-circuiting apertures and a second portion substantially separated from the first portion by an intermediate layer of P-type. One of the main electrodes is in ohmic contact with the first portion, with the intermediate P-type layer exposed through the short-circuiting apertures, with the periphery of the second portion and with the portion of the intermediate layer adjacent to the second portion, so that a photo signal is radiated on the second portion.

Abstract: A diode-integrated high speed thyristor formed into one body by using a separation region for preventing interference between a thyristor and a diode.

Abstract: A thyristor with a gate electrode formed on the side of an anode electrode. An auxiliary region of a large lateral resistance is formed in a surface layer of the substrate between the anode and gate electrodes.

Abstract: A diode-integrated thyristor comprising a region having a function of a thyristor and a region having a function of a diode which are integrated in the same semiconductor substrate and whose rectifying directions are opposite to each other, the carriers in the region having the function of a diode having a longer life time than the carriers in the region having the function of a thyristor.

Abstract: A light-activated semiconductor-controlled rectifier device comprising four layers of PNPN is disclosed in which a part of the edges of the PN junction formed between the intermediate P-type layer and the intermediate N-type layer is exposed on the same side on which the outer P-type layer is exposed, so that a photo-trigger signal is radiated on that exposed part of the edges of the PN junction.