Semiconductor device e.g. IGBT for high voltage inverter

摘要

The IGBT device has an n-type silicon substrate (1) with a large resistance formed by a zone melting process. A p-type implantation region (4) is formed in a first region together with an n-type implantation region (5). A further p-type implantation (3) is formed on the opposite side of the substrate and it is bordered by an n-type buffer zone (2). The implantation layer has a diffusion depth relative to the buffer zone not smaller than 2 mu m. An ion implantation of phosphor is made to form the n-type buffer zone. An ion implantation of boron creates a p-type zone (3b) that is deeper than the n-type buffer zone. The main conduction state is achieved by applying a positive voltage on a gate electrode (7) that is between the emitter electrode (10) and the collector electrode (11). The concentration of a p-type region (3a) is less than or equal to 1.1 times the square root of the product of the concentration of the buffer zone (2) times the total concentration of the latter p-type implantation layer (3a,3b).