Seo, Hyungtak Kim, Young-Bae Lucovsky, Gerald Kim, Il-Doo Chung, Kwun-Bum Kobayashi, Hikaru Choi, Duck-Kyun 2024-01-20T20:01:57Z 2024-01-20T20:01:57Z 2021-09-02 2010-01-15 0021-8979 https://pubs.kist.re.kr/handle/201004/131774 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, 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. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3291124] English AMER INST PHYSICS VOLTAGE ORGANIC TRANSISTORS DIELECTRIC-RELAXATION STRONTIUM-TITANATE CONDUCTION RELIABILITY CAPACITORS INJECTION ORIGIN (BA Enhanced leakage current properties of Ni-doped Ba0.6Sr0.4TiO3 thin films driven by modified band edge state Article 10.1063/1.3291124 1 JOURNAL OF APPLIED PHYSICS, v.107, no.2 JOURNAL OF APPLIED PHYSICS 107 2 scie scopus 000274180600087 2-s2.0-75749134177 Physics, Applied Physics Article VOLTAGE ORGANIC TRANSISTORS DIELECTRIC-RELAXATION STRONTIUM-TITANATE CONDUCTION RELIABILITY CAPACITORS INJECTION ORIGIN (BA