Integrated high-k (k∼19) MIM capacitor with Cu/low-k interconnects for RF application

We demonstrate a high-performance metal-high k insulator-metal (MIM) capacitor integrated with a Cu/low-k backend interconnection. The high-k used was laminated HfO2-Al2O3 with effective k similar to 19 and the low-k dielectric used was Black Diamond with k similar to 2.9. The MIM capacitor (similar to 13.4 fF/mu m(2)) achieved a Q-factor similar to 53 at 2.5 GHz and 11.7 pF. The resonant frequency f(r) was 21% higher in comparison to an equivalently integrated Si3N4-MIM capacitor (similar to 0.93 fF/mu m(2)) having similar capacitance 11.2 pF. The impacts of high-k insulator and low-k interconnect dielectric on the mechanism for resonant frequency improvement are distinguished using equivalent circuit analysis. This letter suggests that integrated high-k MIM could be a promising alternative capacitor structure for future high-performance RF applications.