A transient solution of the Boltzmann equation exposes energy overshoot insemiconductor devices

A method is developed to analyze the transient response of semiconductor de vices in phase space. This is achieved by solving the space and time depend ent electron Boltzmann transport equation self-consistently with the Poisso n and transient hole-current-continuity equation. The result gives the deta ils of the time evolution of the distribution function. The method is appli ed to analyze a bipolar junction transistor. The model predicts the limits in which the steady-state response approximation can be applied. The model exposes a transient overshoot in the high energy tail of the distribution f unction.(C) 1999 American Institute of Physics. [S0021-8979(99)07413-7].