Switching waves in asymmetric thyristor-like structures for incomplete gate turn off regime
Z. S. Gribnikov Institute of Semiconductor Physics, NAS Ukraine, 45 prospekt Nauki, Kyiv, 252028, Ukraine
I. M. Gordion, and V. V. Mitin Wayne State University, Detroit, MI 48202, USA zinovi@besm6.eng.wayne.edu
Abstract. A stationary wave of switching is considered in an infinite thyristor-like structure (TLS).This wave is initiated by the controlling gate current which differs from a certain equilibrium current Jg0(j) providing a neutrally equilibrium (translationally invariant) position of the transition layer between a blocked (OFF-) region and an open (ON-) region for a given current density j in the ON-region. The dependence of the wave velocity v(Jg, j) on the gate current Jg and the current density j is derived.We deal with structures in which the conductivity of gated base I is much higher than the conductivity of ungated base II.The injection level is considered low for base I and high for base II. It is shown that the velocity of the switching wave (i.e. the speed of transient processes in TLS) is determined mainly by parameters of base II. It is also demonstrated that a high speed of operation can be reached in structures with a moderately long base II (the length of the base should exceed 1-2 bipolar diffusion lengths) and a small lifetime of carriers in this base.