Abstract
Mixed HfTaOx dielectric has been deposited by radio frequency (RF) magnetron co-sputtering of HfO2 and Ta2O5 targets on Si substrates and with Pt bottom electrode for metal-oxide-semiconductor (MOS) and metal-insulator-metal (MIM) structures, respectively. HfTaOx layers are characterized by X-ray photoelectron spectroscopy (XPS) to examine the chemical composition. Surface morphology and crystallinity of the deposited film were examined, using by atomic force microscopy (AFM) and grazing incidence X-ray diffraction (GIXRD), respectively. For both the structures electrical properties have been studied in detail. MOS capacitor capacitance-voltage (C-V) characteristics have been utilized to determine the interface trap density and trap distribution in the silicon band gap. A small capacitance non-linearity and low dissipation factor were found in the Pt/HfTaOx/Pt MIM structures. (C) 2011 The Japan Society of Applied Physics