SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING SUCH A DEVICE

摘要

The invention relates to a semiconductor device with a substrate (11) and a semiconductor body (11) comprising a bipolar transistor with an emitter region (1), a base region (2) and a collector region (3) comprising a first, a second and a third connection conductor, which emitter region (1) comprises a mesa-shaped emitter connection region (IA) provided with spacers (4) and adjacent thereto a base connection region (2A) comprising a conductive region (2AA) of poly crystalline silicon. In a device (10) according to the invention, the base connection region (2A) comprises a further conducting region (2AB), which is positioned between the conductive region (2AA) of poly crystalline silicon and the base region (2) and which is made of a material with respect to which the conducting region (2AA) of polycrystalline silicon is selectively etchable. Such a device (10) is easy to manufacture by means of a method according to the invention and its bipolar transistor possesses excellent RF properties.