Transverse stability of an impact-ionization front in a Si p(+)-n-n(+) structure

The transverse stability of an impact-ionization front in a large-area silicon p(+)-n-n(+) is studied. An analytical model allowing for simultaneous motion of the ionization front and displacement of the majority carriers from the nondepleted part of the n base is proposed. The stability of a planar front is investigated, the growth increments are calculated, and the physical mechanisms of instability are indicated. A criterion is formulated for quasistable propagation of a wave. (C) 1997 American Institute of Physics.