The phenomenon of “sharp corner” of Electrolyte-Oxide-Semiconductor structure for copper ions detection

We report a “sharp corner” phenomenon in the diodetype current-voltage (I-V) curves of the Electrolyte-Oxide-Semiconductor (EOS) structure which is made up of Cu-ion solution, SiO2 layer and Si substrate. The phenomenon just appears when the voltage scans from positive value to negative value due to the particularity in electrochemical interaction between Cu ions and Si-SiO2 system. Two kinds of Cu-ion electrolyte solution and different test conditions were employed to study the phenomenon. Other samples had also been tested to compare with the phenomenon. It has the potential to be developed into an electrochemical method of detecting Cu ions in solution phase.