Integrated injection logic with heavily doped injector base self-aligned

Abstract

An integrated injection logic semiconductor structure having a double diffused lateral PNP transistor and an inverted vertical NPN transistor includes an extended region of epitaxial silicon doped N type by introduction of suitable impurity from two separate regions of the semiconductor surface. This extended N type region, which functions as the base of the PNP transistor, allows an adjoining P type region, which in prior art structures served only as the collector, to be utilized as both the collector and the collector contact, thereby reducing the size of the semiconductor structure. Said N type region substantially lessens the series resistance between the base of the NPN transistor and the collector of the PNP transistor, to thereby facilitate manufacture of integrated injection logic circuits operating faster, at higher current levels, and at higher gain than integrated injection logic circuits not utilizing this invention. The extended N type region also facilitates the manufacture of faster multiple collector integrated circuit structures. Additionally, this invention will be useful in fabricating a more compact double diffused lateral transistor structure.