Abstract: Disclosed is a semiconductor device with a bipolar transistor and method of fabricating the same. The device may include a collector region in a semiconductor substrate. A base pattern may be disposed on the collector region. A hard mask pattern may be disposed on the base pattern. The hard mask pattern may include a buffering insulation pattern and a flatness stopping pattern stacked in sequence. An emitter electrode may be disposed in a hole that locally exposes the base pattern, penetrating the hard mask pattern. A base electrode may contact an outer sidewall of the hard mask pattern and may be disposed on the base pattern. The flatness stopping pattern may contain an insulative material with etching selectivity to the buffering insulation pattern, the emitter electrode, and the base electrode.