Characterization and comparison of two metal-insulator-metal capacitor schemes in 0.13 /spl mu/m copper dual damascene metallization process for mixed-mode and RF applications

In this paper, we report on two manufacturable, low-cost MIM capacitor structures with Cu and Ta bottom electrode for 0.13 /spl mu/m 6-level Cu-metallization technology. The quality factor (Q) of the MIM capacitor with SiN dielectric directly deposited on the Cu surface is found to be twice as high as that with Ta bottom plate. Both the Cu and Ta bottom-plate capacitors were found to exhibit low leakage and high breakdown field strength characteristics, as well as absence of dispersive behaviour, and good voltage and temperature linearity. The impact of the Cu surface roughness on the dielectric reliability was reduced by optimizing SiN precursor gas flow.