| 摘要 |
PURPOSE:To prevent generation of an inversion layer when a Darlington circuit is to be constituted using two transistors by a method wherein the high impurity concentration region having the conductive type being different from the conductive type of the base region is provided in a semiconductor substrate surrounded with the front part and the rear part base regions and a bias resistor. CONSTITUTION:The Darlington circuit is constituted of the front part transistor 11, the rear part transistor 12, and the bias resistors 13, 14 connected in series. Namely, the N type base region 22 and the P type emitter region 24 being positioned therein to constitute the front part transistor 11 are provided in the P type Si substrate 21 to constitute the common collector region, and the N type base region 3 and the P type emitter region 25 being positioned therein to constitute the rear part transistor 12 are formed adjoining to the former. At this constitution, the P<+> type well part is newly provided perpendicularly in the region surrounded with the two base regions 22, 23 and the bias resistor 13 to prevent extension of a depletion layer, and the collector saturation voltage characteristic of the circuit is improved. |
