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. (C) 2004 Elsevier Ltd. All rights reserved.