Observation of current-density filamentation in multilayer structures by EBIC measurements

The total current-voltage characteristics of the p+-n+-p-n− and n+-p-n-p− diodes under investigation show branches of negative differential resistance. Accompanied by the appearance of negative differential resistance is a filamentation of current-density and electric-field distribution. Electron beam-induced current (EBIC) measurements were used to examine the properties of filamentation from the point of view of self-organized pattern formation. Besides the detection of the spatial distribution of the electric field, EBIC measurements give information on current-density filamentation. Furthermore, the perturbation by the electron beam gives information on the dynamic behavior of the filamentary structure.