A semiconductor device has bipolar transistors on a substrate. There is also an insulating film on the substrate, covering the bipolar transistors. On this insulating film is emitter wiring, sticking through openings in the insulating film (first openings) to be electrically coupled to the emitter layer of the bipolar transistors. On the emitter wiring is a protective film. On the protective film is a bump, sticking through an opening in the protective film (second opening) to be electrically coupled to the emitter wiring. In plan view, the second opening is included in the area that is inside the bump and outside the first openings.