Channeling cracks in low-k dielectrics have been observed to be a key reliability issue for advanced interconnects. The constraint effect of surrounding materials including stacked buffer layers has been studied. This paper analyzes the effect of interfacial delamination on the fracture condition of brittle thin films on elastic substrates. It is found that stable delamination along with the growth of a channel crack is possible only for a specific range of elastic mismatch and interface toughness. An effective energy release rate is defined to account for the influence of interfacial delamination on both the driving force and the fracture resistance, which can be significantly higher than the case assuming no delamination.

This paper is presented at 2007 MRS Spring Meeting at San Francisco on Wednesday, April 11, 2007. The attached manuscript will be submitted to the MRS Proceedings for Symposium B: Materials, Processes, Integration, and Reliability in Advanced Interconnects for Micro- and Nano-Electronics.

Update on August 16, 2007: This paper has been published in: Materials, Processes, Integration and Reliability in Advanced Interconnects for Micro- and Nanoelectronics, edited by Q. Lin, E.T. Ryan, W-L. Wu, D.Y. Yoon (Mater. Res. Soc. Symp. Proc. Vol. 990, Warrendale, PA, 2007), B06-04.