N. Shigyo et Y. Niitsu, PHYSICAL MODELS FOR BIPOLAR DEVICE SIMULATION AND THEIR EFFECTS ON CUTOFF FREQUENCY, I.E.E.E. transactions on electron devices, 40(11), 1993, pp. 2087-2089
The effects of individual physical models on the bipolar ac characteri
stic, i.e., the cutoff frequency f(T), have been investigated. It has
been found that the model for the intrinsic carrier concentration n(i)
has a negligible effect on the f(T)-I(C) characteristics. The effects
of the carrier mobility mu and the apparent bandgap narrowing DELTAE(
g)app on f(T) were found to be different for a device structure of bip
olar transistor. A sufficient agreement between the simulation and mea
surement of the f(T)-I(C) characteristics has been obtained using the
proposed physical models.