Dielectric reliability in copper low-k interconnects

Time Dependent Dielectric Breakdown is used for assessing the integration quality of advanced copper low-k interconnects. In this contribution examples are shown for the various relevant physical mechanisms. These include interface related degradation - such as the CMP/cap or the barrier/dielectric interfaces - or intermetal dielectric degradation linked to plasma modification. A method is proposed for systematic investigation of various plasmas that potentially can influence the dielectric quality. Using spacing values relevant to the 32 nm technology node experimental TDDB data relevant to that node are also reported.