Numerical analysis and interpretation of the small-signal minority-carrier transport in bipolar devices

A simple and efficient one-dimensional numerical technique is presented that determines the small-signal minority-carrier transport in the quasineutral regions of bipolar devices, such as diodes and transistors, under sinusoidal excitation. The technique is applied to study small-signal properties of p-n junction diodes and bipolar transistors. Examples treated include the frequency dependence of transistor current gain, the diffusion capacitance of a quasineutral base or emitter, and base-layer carrier propagation delay