THE STRUCTURE OF CURRENT FILAMENTS IN SI-ZN

The internal structure of steady-state current filaments in Si:Zn, whi ch appeared under conditions corresponding to a superlinear section of the global current-voltage characteristics, have been studied. The sp atial distributions of the current in the filaments were determined by photometric analysis of the radiation emitted by a gas when a current was passed through a system formed by a semiconductor and a gas-disch arge gap. This method ensured spatial resolution of approximately 10 m m-1 and made it possible to describe quantitatively the distributions involving a drop in the current density of greater than or similar to 10(2). Transformation of the profile and amplitude of the current dens ity of the filaments in the region of a hysteresis of the current-volt age characteristic has been studied. The results support a diffusion m echanism of the instability which accounts for the filamentation of th e current.