A Reliability Model for Interlayer Dielectric Cracking During Fast Thermal Cycling

摘要

Interlayer dielectric (ILD) cracking can result in short circuits of multilevel interconnects. This paper presents a reliability model for ILD cracking induced by fast thermal cycling (FTC) stress. FTC tests have been performed under different temperature ranges (AT) and minimum temperatures (Tnlin). The Weibull distributions of time to failure are relatively well behaved with a similar slope. The number of cycles to failure increases with increasing T_(min), even though AT increases. The Coffin-Manson law is used to model the failure rate only for test results having the same Tmjn. The obtained exponent value is in the range of brittle material cracking mechanism, which is confirmed by failure analysis and modelling of the failure mechanism. An extended Coffin-Manson law is developed to model failure rates during FTC stresses.