| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device which has both a low-noise bipolar transistor and high-speed bipolar transistor mounted thereon. SOLUTION: This semiconductor device 74 comprises first and second bipolar transistors 72, 73 at first and second regions on a semiconductor substrate 31. The first transistor 72 has an emitter region composed of a low-concn. impurity region 46 adjacent to a base region 44 at the termination facing the interface of the emitter junction with an insulation film 53 and a high-concn. impurity region 47 formed with an impurity of a semiconductor film 58. The second transistor 73 has an emitter region 51 comprising a high-concn. impurity region 51 with an impurity diffused from a semiconductor film 60. |
