Lanthanide (Tb)-doped HfO2 for high-density MIM capacitors

A high-density metal-insulator-metal (MIM) capacitor with a lanthanide-doped HfO₂ dielectric prepared by physical vapor deposition (PVD) is presented for the first time. A significant improvement was shown in both the voltage coefficient of capacitance (VCC) and the leakage current density of MIM capacitor, yet the high capacitance density of HfO₂ dielectrics was maintained by achieving the doping of Tb with an optimum concentration in HfO₂. This technique allows utilizing thinner dielectric film in MIM capacitors and achieving a capacitance density as high as 13.3 fF/μm² with leakage current and VCC values that fully meet requirements from year 2005 for radio frequency (RF) bypass capacitors applications.