Mechanism of sequential switching of current filaments in an avalanche $S$-diode

The paper presents the results of a study of a sequential switching of current filaments in an avalanche $S$-diode with deep iron centers. It has been experimentally shown that at a high repetition rate (100 kHz), the current filaments are distributed over the area of the electron-hole junction more uniformly compared to switching at a low frequency (100Hz). In this case, the switching voltage at the first switching event of the avalanche $S$-diode is always higher than at the second one. To analyze the results, a numerical experiment on the formation of a locally heated region with an increased concentration of nonequilibrium carriers was proposed. Simulation of the dynamics of carrier redistribution under conditions of nonuniform heating of the $S$-diode allows one to propose a new mechanism for sequential switching of current filaments. In this mechanism, the recharging of deep centers in the vicinity of each previous current filament sets the conditions for the formation of each subsequent switching channel.