Monolithic integrated semiconductor circuit - has planar transistor structure as constant current source transistor base zone surrounded by auxiliary collector zone

摘要

The integrated circuit has a series of additional planar transistors, forming constant current sources whose emitter and base zones are parallel connected. One planar transistor, together with a setting resistor, serves as a reference voltage source for the other planar transistors and the planar transistor structure. - The planar transistor structure is provided in an epitaxial layer on a semiconductor substrate of opposite conductivity. It is surrounded by an insulating zone of substrate conductivity, penetrating the epitaxial layer. The structure can reach saturation during operation. The base zone (8) of the transistor structure is surrounded by an auxiliary collector zone (9) of identical conductivity on the free surface (11) of the epitaxial layer (2). The auxiliary collector zone is directly connected to the emitter zone