Challenges of Low Effective-K approaches for future Cu interconnect

Challenges of various low effective-K approaches, including homogeneous low-K and air-gap, for next generation Cu/low-K interconnect will be presented. For homogeneous low-K approach, top issues and possible solutions for K damage, package, and CMP peeling & planarization due to introduction of fragile lower k (KLt2.4) insulator will be focused. For air-gap, various types of air-gaps will be reviewed from the points of cost, layout/designer, and new processes involved.