Ru and RuO2 thin films are considered to be new electrode materials for dynamic random access memories (DRAMs) and ferroelectric nonvolatile memories because of their low resistivity and good thermal and chemical stabilities. In this study these thin films were pepared by reactively sputtering a Ru metal target (99.9% purity) in an argon and oxygen atmosphere. XPS spectra were collected with a PHI 1600 spectrometer equipped with a monochromatic Al Kα x-ray source and a multichannel detector. This report includes XPS spectra of Ru 3d and O 1s core regions for these samples. The binding energy of Ru 3d5/2 is determined as 280.0 and 280.8 eV for Ru and RuO2 films, respectively. The presence of a small amount of Ru with higher oxidation states, such as Ru6+ and Ru8+, is shown at the surface of the RuO2 thin film.

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Polycrystalline HfO 2 thin film capacitors were prepared by anodizing sputter-deposited Hf films, and their capacitor and leakage current properties were studied. Electrical measurements were performed for the parallel-plate Hf anodized capacitors with an Al-HfO 2 -Hf (metal-insulator-metal) structure, and high capacitance density (0.6 "F/cm 2 ) and low dielectric loss (0.0095) were obtained for a very thin-oxide capacitor anodized at 10 V. In addition, the leakage current density of this capacitor was about 5 Â 10 À9 A/cm 2 at an applied voltage of 5 V. The leakage current density (J) of HfO 2 capacitors as a function of applied electric field (E) was investigated for several capacitors with different oxide thicknesses, by plotting lnðJÞ vs E 1=2 curves. As a result, it was revealed that the conduction mechanism is due to Schottky emission, irrespective of the oxide thickness.

Oxygen-containing Pt and Pt oxide thin films were prepared by reactive sputtering in Ar and O2 gas atmosphere and effects of oxygen flow ratio on crystallinity, chemical bonding state and resistivity were studied. Polycrystalline oxygen-containing Pt and amorphous Pt oxide thin films were obtained at O2 flow ratios below 20% and above 30%, respectively. It is confirmed that these films are composed of the mixture of Pt, PtO and PtO2 and the oxygen content in these films increases with an increase in the O2 flow ratio. Though PtOx films with x ≤0.6 show low resistivity with metallic conduction, those with higher oxygen content show semiconducting characteristics and their resistivity increases with increasing oxygen content.

We investigated the influence of ZrN/Zr bilayered film thickness on the (111) Cu orientation and the thermal stability of the Cu/ZrN/Zr/Si contact system by X-ray diffraction and Auger electron spectroscopy analyses. We confirmed that the single-oriented growth of (111) Cu can be realized by interposing the ZrN (400 Å)/Zr (200 Å) bilayered film between Cu and Si. It was revealed that the (111) Cu/(111) ZrN/(002) Zr/(001) Si contact system is satisfactorily stable up to 600°C without undesirable interfacial reaction and interdiffusion, maintaining the low contact resistivity of the ZrSi2 adhesion layer at the Si interface and the single-oriented state of the (111) Cu overlayer.