New strategy to improve the mechanical strength and to reduce potential contamination of dielectric materials for double level metal integration

This work concerns a new strategy for dual damascene Cu/low k integration in order to improve the mechanical strength and to reduce the contamination of the dielectric materials. We introduce the spacer concept in the dual damascene integration scheme with SiLK(R) dielectric. Two materials have been studied as spacers: SiN and TiN. The comparison is based on morphological aspects as well as electrical CD and Kelvin via resistance measurements for different strategies.