Mechanical Stress Influence on Electronic Transport in Low- $k$ SiOC Dielectric Dual Damascene Capacitor

The electronic package with lead-free welding processes must be performed at higher temperature whereas the heat induces to mechanical stress. In this letter, we fabricate a low-k SiOC dielectric comb capacitor with dual damascene (DD) structures to study the mechanical stress influence on leakage current I_leak in DD by bending samples. Tensile stress causes increase of the I_leak because of the decrease of energy band barrier Φ of SiOC dielectric. In contrast, compress stress increases Φ of SiOC and decreases its I_leak. Finally, we conclude that the electron transport in DD is dominated by Schottky emission. We found that the variation of I_leak is attributed by the change of energy band barrier under mechanical stress.