PURPOSE: To reduce the influence of the parasitic transistoor generated by the base and semiconductor substrate of a transistor and by the anode of a diode by a method wherein, in forming the diode and the transistor monolithically, a cut-off region of reverse conductivity type is provided between these elements.
CONSTITUTION: A P type base region 12 of the transistor is diffusion-formed in the N type semiconductor substrate 11 serving as the collector, and is then provided with an N type emitter region 13 therein. A P type anode region 14 is diffusion-formed in the same substrate 11 in adjacency to this transistor region, and constructs the diode with the substrate 11. In this construction, a slender P type cut-off region 15 is diffusion-formed between the regions 12 and 14, thereby dividing the transistor region and the diode region. Such a manner causes little influence of the transistor on the reverse recovery time between the collector and emitter, which time then comes into agreement with the reverse recovery time of a diode simple body, resulting in the formation of the device of excellent characteristics.
MURAMOTO KENICHI
TAKAHASHI WATARU
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