• Proceedings of the KIEE Conference
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• 1988.11a
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• pp.172-174
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• 1988

Studies and measurements of open circuit voltage in a metal/insulator/metal structure where metal are electrodes, when the insulator molecules have dipole moments all oriented parallel to each other have been reported here. The measured voltage has been shown to be directed related to the dipole moment of the molecules in the films. The insulator ultra thin films was deposited on them by the Langmuir-Blodgett technique to obtain the structure referred to as z type and Hetero structure of LB films.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.2
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• pp.147-152
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• 2016

In this study, we fabricated Ag-based electrochemical metallization memory devices which is also called conductive-bridge random-access memory (CBRAM) in order to investigate the resistive switching behavior depending on the bottom electrode (BE). RRAM cells of two different layer configurations having $Ag/Si_3N_4/TiN$ and $Ag/Si_3N_4/p^+$ Si are studied for metal-insulator-metal (MIM) and metal-insulator-silicon (MIS) structures, respectively. Switching voltages including forming/set/reset are lower for MIM than for MIS structure. It is found that the workfunction different affects the performances.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.6
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• pp.648-654
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• 2003

Diamond MIS(Metal-Insulator-Semiconductor) diodes and MISFETs(Metal-Insulator-Semiconductor Field Effect Transistors) were fabricated by employing various fluorides as gate insulator, and their electrical properties were closely investigated by means of C-V measurements. The A1/BaF$_2$/diamond MIS structure exhibited outstanding electrical properties. The MIS diode showed a very low surface state density of ∼10$\^$10//$\textrm{cm}^2$ eV near the valence band edge, and the observed effective mobility(${\mu}$$\_$eff/) of the MISFET was 400 $\textrm{cm}^2$/Vs, which is the highest value obtained until now in the diamond FET. From the chemiphysical point of view, the above result might be explained by the reduction of adsorbed-oxygen on the diamond surface via strong chemical reaction by the constituent Ba atom in the insulator during the film deposition(Oxygen-Gettering Effect).

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.959-964
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• 2004

A low-dimensional metal frequently exhibits a metal-insulator transition through a charge-density-wave (CDW) or a spin-density-wave (SDW) which accompany it's structural changes. The transition temperature is thought to be determined by the amount of energy produced during the transition process and the softness of the original structure. $AMo_4O_6$ (A=K, Sn) are known to be quasi-one dimensional metals which exhibit metalinsulator transitions. The difference of the transition temperatures between $KMo_4O_6$ and $SnMo_4O_6$ (A=K, Sn) is examined by investigating their electronic and structural properties. Fermi surface nesting area and the lattice softness are the governing factors to determine the metal-insulator transition temperature in $AMo_4O_6$ compounds.

• Proceedings of the Korean Magnestics Society Conference
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• 2015.05a
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• pp.139-139
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• 2015

• Proceedings of the Materials Research Society of Korea Conference
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• 2000.11a
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• pp.39-39
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.19.2-19.2
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• 2011

The $(Sr_{0.75},\;La_{0.25})TiO_3$ (SLTO) ultra-thin films with various thicknesses have been grown on Ti-O terminated $SrTiO_3$(100) substrate using Laser-Molecular Beam Epitaxy (Laser MBE). By monitoring the in-situ specular spot intensity oscillation of reflection high energy electron diffraction (RHEED), we controlled the layer-by-layer film growth. The film structure and topography were verified by atomic force microscopy (AFM) and high resolution thin film x-ray diffraction by the synchrotron x-ray radiation. We have also investigated the electronic band structure using x-ray absorption spectroscopy (XAS). The ultra thin SLTO film exhibits thickness driven metal-insulator transition around 8 unit cell thickness when the film thickness progressively reduced to 2 unit cell. The SLTO thin films with an insulating character showed band splitting in Ti $L_3-L_2$ edge XAS spectrum which is attributed to Ti 3d band splitting. This narrow d band splitting could drive the metal-insulator transition along with Anderson Localization. In optical conductivity, we have found the spectral weight transfer from coherent part to incoherent part when the film thickness was reduced. This result indicates the possibility of enhanced electron correlation in ultra thin films.

• Bulletin of the Korean Chemical Society
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• v.17 no.1
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• pp.43-45
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• 1996

Structural and electronic properties of an alkali metal fulleride, Rb1C60, was studied. In spite of the chain structure with shortdistance between balls along the crystallographic a-direction, the electronic structure calculation study with the X-ray defined crystal structure shows that Rb1C60 is a three-dimensional metal at room temperature. This result is different from the magnetic experiments in which the compound was found to behave as a quasi-one-dimensional metal. Partial Fermi surface nesting is supposed to be the reason for the metal-insulator transition found in Rb1C60 at ∼50 K.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.7
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• pp.533-538
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• 2001

The barrier height is found to increase from 0.25 to 0.690 eV for Schottky contacts on n-InGaAs using deposition of Ag on a substrate cooled to 77K(LT). Surface analysis leads to an interface model for the LT diode in which there are oxide compounds of In:O and As:O between the metal and semiconductor, leading to behavior as a metal-insulator-semiconductor diode. The metal film deposited t LT has a finer and more uniform structure, as revealed by scanning electron microscopy and in situ metal layer resistance measurement. This increased uniformity is an additional reason for the barrier height improvement. In contrast, the diodes formed at room temperature exhibit poorer performance due to an unpassivated surface and non-uniform metal coverage on a microscopic level.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.2
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• pp.77-82
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• 2018

Electromagnetic wave transmission through periodic metal-insulator-metal(MIM) waveguides as a function of plate thickness has not been extensively studied at various terahertz frequencies. In this paper, we investigate the transmittances through gold MIM slits when a normally incident wave with parallel polarization is considered at several terahertz frequencies. In addition, the results are compared to the case of a perfect electric conductor, and the differences are discussed.