| 摘要 |
PURPOSE:To heighten an FI (field-initiate) effect easily, promote the uniformity of action and improve an OFF characteristic when GTO by a method wherein an impurity semiconductor layer is formed at a digging-in section forming location by means of diffusion, and a resistor region is accurately made up. CONSTITUTION:Impurities with a conduction type reverse to a cathode emitter are diffused at a location of a gate digging-in section of a thyristor with a semiconductor layer P1N1P2N2, and a region P3 is formed. Thus, since an FI gate is made up by means of diffusion, a P3 layer having excellent precision and superior uniformity can be obtained, and a resistor section R1 having excellent accuracy and superior uniformity can also be built up. Since load currents Igf flow through the resistor section R1 and forward bias is generated, and the resistance value of the resistor section R1 does not differ in response to locations when igniting a main thyristor, a bias effect is excellent, and main currents IM can be expanded equally over the whole surface of a cathode. When GTO, an OFF characteristic can be controlled at high accuracy. |
