High-k Metal-Insulator-Metal (MIM) capacitors for RF/Mixed-Signal IC applications

Abstract

In this thesis, development of a series of novel high-A? based MIM capacitors are described for future RF/mixed-signal IC applications. Firstly, high performance MIM capacitors are demonstrated using reactive sputtered HfO2 films. It is shown that doping HfO2 with lanthanide material (Tb) can improve both voltage linearity and leakage current of HfO2 MIM capacitors, allowing further reduction of insulator thickness and achieving higher capacitance density. Secondly, it is demonstrated that the voltage linearity of MIM capacitors can be engineered and virtually zero voltage coefficients can be achieved by using high-A?/SiO2 stacked insulator structure. Thirdly, novel Nb2O5 is demonstrated for RF bypass capacitor application. Nb2O5 MIM with HfO2/Al2O3 barriers delivers a record high capacitance density of 17fF/um2 with excellent reliability and RF properties. Lastly, the high-A? MIM capacitors, developed in this thesis, are successfully integrated into Cu-BEOL and their RF properties are evaluated up to 20 GHz.