Semiconductor element capable of withstanding high voltage

摘要

A semiconductor element such as a thyristor or a transistor which is capable of withstanding a high voltage comprises a semiconductor substrate of a pnpn-four layer structure (for a thyristor) or of a npn-three layer structure (for a transistor). An intermediate p-type layer is composed of a low concentration layer region located adjacent to an n-type layer and a high concentration layer region located adjacent to the other n-type layer. The high concentration layer region is formed through diffusion of aluminium so that the maximum concentration thereof becomes at least equal to 5x1016 atoms/cm3. A method of manufacturing such semiconductor element is also disclosed.