Material and electrical characterization of HfO2 films for MIM capacitors application

Abstract

Thin films of HfO2 high-κ dielectric have been prepared by pulsed-laser deposition (PLD) at various deposition conditions. X-ray diffraction (XRD), atomic force microscopy (AFM), and secondary ion mass spectroscopy (SIMS) were used to characterize the deposited films. Experimental results show that substrate temperature has little effect on the stoichiometry, while deposition pressure plays an important role in determining the ratio of Hf and O. The electrical properties of HfO2 Metal-Insulator-Metal (MIM) capacitors were investigated at various deposition temperatures. It is shown that the HfO2 (56 nm) MIM capacitor fabricated at 200°C shows an overall high performance, such as a high capacitance density of ∼3.0 fF/μM2, a low leakage current of 2×10-9 A/cm2 at 3 V, etc. All these indicate that the HfO2 MIM capacitors are very suitable for use in Si analog circuit applications.