HETEROJUNCTION BIPOLAR TRANSISTOR GEOMETRY FOR IMPROVED POWER AMPLIFIER PERFORMANCE

摘要

A heterojunction bipolar transistor includes a base mesa, an emitter assembly formed over the base mesa, and a base contact. The emitter assembly includes multiple circular sectors. Each circular sector is spaced apart from one another such that a sector gap is formed between radial sides of adjacent circular sectors. The base contact, which is formed over the base mesa, has a central portion and multiple radial members. Each radial member extends outward from the central portion of the base contact along a corresponding sector gap. As such, each of the circular sectors of the emitter assembly is separated by a radial member of the base contact. The number of circular sectors may vary from one embodiment to another. For example, the emitter assembly may have three, four, six, or more circular sectors.