Distinction of intrinsic and extrinsic breakdown failure modes of Cu/low-k interconnects

Three distinct leakage current profiles in a Cu/low-k interconnect systems were observed from breakdown voltage characterization. Consequently, extrinsic and intrinsic failure modes are able to be distinguishable based on the I-V profile showing the different temperature dependence and statistical distribution. Normal distribution statistical analysis further attested the different failure mechanisms obtained, and the physical failure analysis was performed to show the breakdown failure mechanism of Cu/low-k interconnect systems.