Qualitative basic operation of BJts What is a bjt? A BJT consists of two back-to-back p-n junctions The middle region, the base, is very thin The three regions are the emitter, base, and collector Carriers are injected (emitted) into the base from the emitter Since the base is thin most carriers injected into base diffuse into collector What does a thin base thickness "mean Base thickness is much thinner than the diffusion length of carriers injected from the emitter OE F Schubert, Rensselaer Polytechnic Institute, 2003© E. F. Schubert, Rensselaer Polytechnic Institute, 2003 2 Qualitative basic operation of BJTs What is a BJT? A BJT consists of two back-to-back p-n junctions. The middle region, the base, is very thin. The three regions are the emitter, base, and collector. Carriers are injected (“emitted”) into the base from the emitter. Since the base is thin, most carriers injected into base diffuse into collector. What does a “thin base thickness” mean? Î Base thickness is much thinner than the diffusion length of carriers injected from the emitter