First investigation of metal–insulator–metal (MIM) capacitor using Pr2O3 dielectrics

Metal–insulator–metal (MIM) capacitors with Pr₂O₃ as high-k material have been investigated for the first time. We varied the thickness of the Pr₂O₃ layers as well as the bottom electrode material. The layers are characterised using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM) and secondary ion mass spectroscopy (SIMS). Preliminary information on the interaction of water with the films was obtained from XPS and ab initio pseudopotential calculations. The electrical characterisation shows that Pr₂O₃ MIM capacitors can provide higher capacitance densities than Si₃N₄ MIM capacitors while still maintaining comparable voltage coefficients of capacitance. The Pr₂O₃ dielectric material seems to be suitable for use in silicon RF applications.