Spectroscopic analysis of leakage current of pre- and post-stressed sol-gel-based TiO2 and SiO2/TiO2 stack films

This paper investigates the trap property of pre-and post-stressed TiO2/SiO2 stacks by the spectroscopic analysis of the leakage current. It is suggested that transport is ruled by the space-charge-limited current controlled by negative-charged traps. Spectroscopic analysis of the current fluctuation demonstrates that after stress application the current path varies with the polarity of the top electrode; this suggests that there are at least two-different paths inside the degraded TiO2/SiO2 stack.