摘要 |
1. High-frequency semiconductor switching device constituted by a semiconductor wafer comprising alternating layers of conductivity type p and n, surface layers of type n of high doping level being flush at least with regions of each of the two faces of the wafer, at least one (7) of said layers of n type and of high doping level being superposed on a layer (2) of the same n type and of weaker doping level, the inner layers of the device enclosing atoms of bodies constituting recombination centres for electrical charges, characterized in that said layer (7) of type n of high doping level superposed on a layer (2) of the same type n of weaker doping level comprises a plurality of channels (29, 30) formed by extensions of the layer of type n with weaker doping level, and in that the ratio of the total surface of the plurality of channels to the surface of the region of high doping level lies between 5 and 10% in such a manner that the atoms of bodies forming the recombination centres for the electrical charges on their introduction can diffuse without obstruction towards said inner layers of the device. |