Device structures on porous silicon studied by scanning electron microscopy in the electron-beam current mode

Contacts metal/porous silicon and pill device structures on porous silicon were studied by scanning electron microscopy in the electron-beam-induced current mode. It is shown that the drift processes are dominant in operation of porous silicon-based devices. We present the theoretical analysis of electron-beam-induced current measurements and estimate such important parameters of device structures as: the width of the space-charge region (several microns), charge state density in the space-charge region (10(14)-10(15) cm(-3)), and electron drift length (up to 10(-3) cm). The spatial distribution of the electric field in space-charge region was derived. The possibility of studying the influence of porous silicon/crystalline silicon interfaces on operation of porous silicon-based devices has been illustrated. (C) 1996 American Institute of Physics.