| 摘要 |
PURPOSE:To obtain a pinch resistor as to enable to control a current to flow at breakdown time by a method wherein a second diffusion resistance layer the same conductive type with a first diffusion resistance layer is continuously connected to the low electric potential side of the first diffusion resistance layer as the diffusion layer united in one body of both. CONSTITUTION:A first p type base diffusion resistance layer 4 is formed on the surface of an island region 2 consisting of an n type epitaxial layer, an n<+> type emitter diffusion layer 5 is provided at a part of the surface thereof to convert the p type diffusion layer 7 positioning directly thereunder into high resistance, the second p type diffusion resistance layer 8 is continuously connected being united in one body to the low electric potential side (the L side) of the p type diffusion layers 4, 7, and electrodes H, L to be connected respectively ohmically to the high electric potential side (the H side) and the low electric potential side are provided. The resistance value of the first p type diffusion layer 4 converted into high resistance is designated as R1, the resistance value of the second p type diffusion layer 8 continuously connected to the low electric potential side is designated as R2, and when a breakdown voltage is applied between the electrodes H and L, because resistance is divided into R1 and R2, a reverse bias voltage applied to p-n junction of the n<+> type layer 5 and the p type layer 4 is restrained under the breakdown voltage. Moreover, even when breakdown is generated, because the R2 component survives, the current can be controlled. |
