| 摘要 |
PURPOSE:To prevent the resistance value from being varied by variation in temperature and to obtain stable characteristics over a wide range of operational temperatures, by forming a gate resistance by the connection between a resistance having a negative temperature coefficient and a resistance having a positive temperature coefficient in series. CONSTITUTION:A diffusion resistance of a third semiconductor region 4 is represented by RGK1 and a wiring resistance of a polysilicon layer 7 is represented by RGK2. This diffusion resistance RGK1 and the wiring resistance RGK2 are connected in series by a third electrode 14. A resistance RGK between a second electrode 13 (gate) and a fourth electrode (cathode) is equal to the sum of a diffusion resistance RGK1 and a wiring resistance RGK2, that is, RGK=RGK1+RGK2. The diffusion resistance RGK1 of the third semiconductor region 4 has a positive temperature coefficient and the resistance value thereof is increased as the operational temperature (Ta) increases. The wiring resistance RGK2 has a negative temperature coefficient and the resistance value thereof is decreased as the operational temperature increases. The positive and negative temperature coefficients can be set respectively at appropriate values so as to leave the value of the gate resistance RGK fixed even if the operational temperature is varied. |
