EM lifetime improvement of Cu damascene interconnects by p-SiC cap layer

Mean time to failure (MTF) of Cu damascene interconnects with p-SiC cap layer is achieved to be approximately 2 times as long as that with conventional p-SiN cap layer. This improvement can be explained by the difference of adhesion between Cu and the cap layer. It is also found that Cu dominant diffusion path is the interface between Cu and the cap layer for Cu interconnects with TaN/Ta and p-SiC, p-SiN.