Electrical leakage at low-K polyimide/TEOS interface

The effect of low-K polymer passivation on electrical leakage was investigated to evaluate the reliability of polymer integration on device wafers. Polyimide passivation over Al(0.5% Cu) interconnects inlaid in TEOS increases the intralevel leakage current mainly along the polyimide/TEOS interface. Moisture absorbed in the polyimide further increases the inter facial as well as bulk leakages. These findings emphasize the importance of separating interconnects from direct contact with polyimide/TEOS interfaces to alleviate electrical isolation problems in multilevel interconnect architecture that employs low-K polymer dielectrics.