| abstract |
Provided is a common-emitter and common-base heterojunction bipolar transistor disposed on a packaging substrate with a heat sink, including a common-base heterojunction bipolar transistor having a first base, a first emitter and a first collector, a common-emitter heterojunction bipolar transistor having a second base, a second emitter and a second collector, a heat shunt bridge for connecting the first emitter with the second collector, a first pad for being connected with the first base and a first copper pillar, a second pad for being connected with the first collector and a second copper pillar, a third pad for being connected with the second base and a third copper pillar, and a fourth copper pillar disposed above the second emitter; the common-emitter and common-base heterojunction bipolar transistor is flip-chip mounted on the packaging substrate, and the fourth copper pillar is soldered on the heat sink. |