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1% Ni-doped barium strontium titanate (BST) thin film deposited at room temperature reveals the significantly enhanced leakage current performance which is extraordinarily effective for low temperature applications. Significant leakage current suppression of >2 orders was achieved for electric fields from 0.25 to 2 MV/cm in Pt/Ni-doped BST/Pt metal-insulator-metal (MIM) capacitor cells compared to undoped BST. For Ni doping at the 1% level, the spectral dependence of (i) the imaginary part of the complex dielectric constant, [variant_greek_epsilon]2, obtained from the rotating compensator enhanced spectroscopic ellipsometry and (ii) OK1 absorption spectra obtained from synchrotron x-ray absorption spectroscopy shows significant differences (0.26±0.15 eV) in the conduction band edge trap depth relative to undoped BST. The valence band (VB) edge x-ray photoelectron spectroscopy analysis reveals the Fermi energy level downshift of 0.4 eV for Ni-doped BST toward the VB edge. There is a direct correlation between these changes in band edge states of BST thin films with Ni doping and the improved electrical performance in MIM capacitors led by the qualitatively different charge injection mechanism. The proposed transition metal doping process and analysis approach provide a pathway for charge injection control driven by band edge state changes in other perovskite oxides for low temperature (i.e., room temperature) applications. [ABSTRACT FROM AUTHOR]

Perovskite type conducting materials (Ca, Sr)RuO[sub 3] and (Ba, Sr)RuO[sub 3] were prepared by rf magnetron sputtering as bottom electrodes for (Ba, Sr)TiO[sub 3] thin film capacitors. The crystallinity, interface property, and electrical properties of the (Ba, Sr)TiO[sub 3] capacitor applying the perovskite oxide electrodes were investigated. The interface between the dielectric and the electrode were analyzed by high-resolution electron microscopy and Auger electron spectroscopy. The interface had a marked effect on the electrical properties of the (Ba, Sr)TiO[sub 3] thin films. Dielectric constant for the (Ba, Sr)TiO[sub 3] had considerable dependence on the thickness of interfacial layer. The leakage current density of the capacitor was sensitive not only to the structural match but also to the chemical match between (Ba, Sr)TiO[sub 3] and the electrode. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Deals with a study on the electrical properties of (barium (Ba),strontium (Sr))titanium oxide thin films deposited on (Ba,Sr)ruthenium oxide electrodes to demonstrate the advantageous use of tailored electrodes. Effect of structural similarity and chemical compatibility on the dielectric behavior of the films; Experimental procedure; Results and discussion; Conclusion.

The dielectric relaxation of HfO2 thin films grown by atomic-layer deposition (ALD) was studied as a function of frequency from 1 kHz to 5 GHz. The dielectric relaxation of the ALD HfO2 films followed a power-law dependence known as the Curie–von Schweidler relaxation law both in the kHz and GHz ranges, and the relaxation exponents were consistent with the measured dielectric losses. The behavior of the dielectric response for the HfO2 thin films may be attributed to defect sites in the HfO2 layer and/or interface. [ABSTRACT FROM AUTHOR]