SPATIOTEMPORAL BEHAVIOR OF LOCALIZED CURRENT FILAMENTS IN P-N-P-N DIODES - NUMERICAL-CALCULATIONS AND COMPARISON WITH EXPERIMENTAL RESULTS

A two-component evolution equation of reaction-diffusion type derived recently to describe experimental results on the self-organization of current-density filaments in silicon p-n-p-n diodes has been solved nu merically. By using physically reasonable parameters and applying diff erent boundary conditions, good qualitative agreement with experimenta l results is obtained. In particular, the following bifurcation scenar io obtained by increasing the external driving voltage in the experime nt can be reproduced in the calculations: stationary homogeneous curre nt-density distribution leads to static current filament leads to rock ing current filament leads to traveling current filament. Furthermore, it is shown that a period-doubling cascade of integral system variabl es, as, e.g., the device voltage, strongly correlates with the spatiot emporal filament motion which undergoes the same period-doubling route . Even quantitative agreement between numerical and experimental resul ts could be achieved to some extent.