Abstract: The disclosed semiconductor voltage regulator comprises an NPN power transistor connected to a field coil of a battery charging AC generator and turned on and off through an NPN control transistor under the control of a Zener diode, a suppression diode for the field coil, and passive elements. The transistors especially including the power transistor and diodes without or with resistors form an integrated semiconductor element on a semiconductor substrate while the passive elements form a hybrid thick film integrated circuit on a ceramic substrate. The integrated element may be disposed on the ceramic substrate underlaid with a heat sink or directly on the heat sink.

Abstract: A method of manufacturing a semiconductor device having at least one power transistor and a plurality of small signal transistors formed on the same semiconductor substrate is disclosed. First, a base region of the power transistor and an isolating region are formed by diffusion simultaneously in an epitaxial layer on the semiconductor substrate. Second, an emitter region of the power transistor and the collector regions of the small signal transistors are simultaneously formed by diffusion, and finally the bases, and emitters of the small signal transistors are formed in succession by diffusion.