2019 Volume 70 Issue 4 Pages 215-219
An impedance-response-based copper wiring corrosion sensor(CCS)was fabricated using screen printing technique. Filter paper(FP)containing 1 M NaCl solution was set on the zigzag conducting parts of the CCS to control the wet area during impedance measurements using a two-electrode system. Arbitrary values of width w or length L of the FP were chosen to investigate the short circuit current in the direction along or crossing the conducting parts. Impedance spectra with different w values of the FP showed a loop on the Nyquist plane. Loop diameter d increased concomitantly with increasing w values of the FP. Part of the loop was observed in the impedance spectra with different L values of the FP. Values of d estimated from respective parts of the loop increased concomitantly with increasing L values of the FP. Results indicate that these loops are related to the copper-wiring / electrolyte solution interface and that d values increase concomitantly with increasing wet area on the conducting parts. Results of the electrochemical impedance simulation demonstrated the following: solution resistance Rsol is inversely related to the L values; the electric double layer capacitance Cdl increased linearly, concomitantly with increasing L values of the FP; and Rsol and the Cdl increased linearly, concomitantly with increasing w values of the FP. Results demonstrate that the impedance response is related closely to the short circuit current in the direction crossing the conducting parts of the CCS.