PHOTOELECTROCHEMISTRY OF N-SILICON SEMICONDUCTOR IN FLUORIDE MEDIA

The effect of adding [Ru(bpy)(3)](2+) complexes during photoelectroche mical etching of n-silicon on the photocurrent generation is studied. Remarkable enhancement of photocurrent is induced due to the presence of the dye redox system. Redox stabilization of silicon via electron t ransfer process based on remarkable interfacial interaction between re ducing species and the photoelectrode is efficiently achieved. Transie nt photoelectrochemical measurements during anodic dissolution of n-si licon in the presence of the complex redox System resulted in inhibiti on of photocurrent oscillations which was observed at high potentials in the absence of dye redox system. Practically, all photogenerated ho les reaching the silicon electrode surface will be efficiently reacted with the coordination redox system resident at the electrode surface. A mechanism of current oscillations, based on periodic buildup and de cay (hole/electron recombination) of space charge within the superfici al oxide layer is proposed.