Texas Instruments Incorporated
BIPOLAR TRANSISTOR WITH SEGMENTED EMITTER CONTACTS

Abstract:

An integrated circuit includes a transistor having a collector region, a base region and an emitter strip. The collector region includes layer of a semiconductor substrate doped with a dopant of a first conductivity type. The base region includes semiconductor layer over the semiconductor substrate, doped with a dopant of a second conductivity type. An emitter strip within the base region has a first width and is doped with a first dopant of the first conductivity type. A plurality of emitter contacts is located within the emitter strip. Each emitter contact has a second width less than the first width, and includes a second dopant of the first conductivity type. Each emitter contact is spaced from a nearest neighbor emitter contact by a portion of the emitter strip. In some examples the transistor has a common-emitter current gain greater than 3500.