• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.409-409
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• 2011

All solid-state thin film lithium batteries have many applications in miniaturized devices because of lightweight, long-life, low self-discharge and high energy density. The research of cathode materials for thin film lithium batteries that provide high energy density at fast discharge rates is important to meet the demands for high-power applications. Among cathode materials, lithium manganese oxide materials as spinel-based compounds have been reported to possess specific advantages of high electrochemical potential, high abundant, low cost, and low toxicity. However, the lithium manganese oxide has problem of capacity fade which caused by dissolution of Mn ions during intercalation reaction and phase instability. For this problem, many studies on effect of various transition metals have been reported. In the preliminary study, the Sn-substituted LiMn2O4 thin films prepared by pulsed laser deposition have shown the improvement in discharge capacity and cycleability. In this study, the thin films of LiMn2O4 and LiSn0.0125Mn1.975O4 prepared by RF magnetron sputtering were studied with effect of deposition parameters on the phase, surface morphology and electrochemical property. And, all solid-state thin film batteries comprised of a lithium anode, lithium phosphorus oxy-nitride (LiPON) solid electrolyte and LiMn2O4-based cathode were fabricated, and the electrochemical property was investigated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.8
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• pp.729-733
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• 2005

Al electrode for OLED was deposited by FTS (Facing Targets Sputtering) system which can deposit thin films with low substrate damage. The Al thin films were deposited on the cell (LiF/EML/HTL/Bottom electrode) as a function of working gas such as Ar or Ar+kr mixed gas. Also Al thin films were prepared with working gas pressure (1, 6 mTorr). The film thickness and I-V curve of Al/cell were measured and evaluated. In the results, when Al thin films were deposited using pure Ar gas, the turn-on voltage of Al/cell was about 11 V. And using the Ar:Kr($75\%:25\%$) mixed gas, the turn-on voltage of Al/cell decreased to about 7 V.

• Journal of the Korean Ceramic Society
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• v.56 no.3
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• pp.233-255
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• 2019

Thermal batteries are reserve batteries with molten salts as an electrolyte, which activates at high temperature. Due to their excellent reliability, long shelf life, and mechanical robustness, thermal batteries are used in military applications. A high-performance cathode for thermal batteries should be considered in terms of its high capacity, high voltage, and high thermal stability. Research progress on cathode materials from the recent decade is reviewed in this article. The major directions of research were surface modification, compounding of existing materials, fabrication of thin film cathode, and development of new materials. In order to develop a high-performance cathode, a proper combination of these research directions is required while considering mass production and cost.

• Proceedings of the Materials Research Society of Korea Conference
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• 2001.11a
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• pp.83-83
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• 2001

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.990-993
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• 2006

We fabricated top emission organic light emitting diode (TEOLED) with transparent metal cathode Barium and Silver bilayer. Very thin Ba/Ag bilayer was deposited on the organic layer by thermal evaporation. This cathode shows high transmittance over 70% in visible range. And the device with a Ba-Ag has a low turn on voltage and good electrical properties.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.9
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• pp.812-815
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• 2003

In this study, the MgO thin-film passivation layer was adopted to protect passive matrix organic light emitting diode(PMOLED) with the cathode separator from moisture and oxygen. Using the substrate rotate and tilt technique during the deposition, the organic and cathode layers were perfectly covered with MgO. And then, we analyzed the difference of the current-voltage and luminescence characteristics between passivated OLED of the MgO and non-passivated OLED. It was found that the number of dark spot generated from the degradated pixel was decreased owing to the Mgo thin-film passivation layer using the tilt ＆ rotate technique. And the half-life time passivated OLED was improved two times more. Thus, the MgO could be vaccum-deposited under the low temperature and had a merit that the organic layer was not much affected. We can consider that MgO thin film passivation method can be adopted to protect the OLED from moisture and oxygen and can offer the enhancement of lifetime.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.80-85
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• 2019

Vanadium dioxide is a well-known metal-insulator phase transition material. Lots of researches of vanadium redox flow batteries have been researched as large scale energy storage system. In this study, vanadium oxide($VO_x$) thin films were applied to cathode for lithium ion battery. The $VO_x$ thin films were deposited on Si substrate($SiO_2$ layer of 300 nm thickness was formed on Si wafer via thermal oxidation process), quartz substrate by RF magnetron sputter system for 60 minutes at $500^{\circ}C$ with different RF powers. The surface morphology of as-deposited $VO_x$ thin films was characterized by field-emission scanning electron microscopy. The crystallographic property was confirmed by Raman spectroscopy. The optical properties were characterized by UV-visible spectrophotometer. The coin cell lithium-ion battery of CR2032 was fabricated with cathode material of $VO_x$ thin films on Cu foil. Electrochemical property of the coin cell was investigated by electrochemical analyzer. As the results, as increased of RF power, grain size of as-deposited $VO_x$ thin films was increased. As-deposited thin films exhibit $VO_2$ phase with RF power of 200 W above. The transmittance of as-deposited $VO_x$ films exhibits different values for different crystalline phase. The cyclic performance of $VO_x$ films exhibits higher values for large surface area and mixed crystalline phase.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.274-278
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• 2004

In this study, hetero-electrode structures have been fabricated to increase luminescence efficiency. The presence of a thin layer of Sn or Ag at the organic-aluminum interface enhanced both electron injection efficiency and electroluminescence when compared to OLEDs using homogeneous electrode. In this paper, the effect of the cathode using Sn/Al hetero electrode structure is observed. Electric properties of the OLED using Sn/Al hetero cathode are improved in comparison of only Al cathode. The hetero-electrode existing different energy level induces the advanced structure of OLED can accumulate electron density. The luminescence efficiency of OLED with Sn/Al of Ag/Al cathode is higher because of their higher electron injection efficiency. And, the turn on voltage of the OLED device using Sn thin layer is lowest as about 10 V.

• Journal of the Korean Ceramic Society
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• v.43 no.12 s.295
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• pp.788-797
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• 2006

An anode-supported SOFC single cell having $5{\mu}m$ thin electrolyte was fabricated cost-effectively by tape casting, laminating, and co-filing of anode (NiO-YSZ), cathode (LSM-YSZ), and electrolyte (YSZ) components. The optimal slurry compositions of the green tapes for SOFC components were determined by an analysis of the mean diameter, the slurry viscosity, the tensile strength/strain of the green tapes, and their green microstructures. The single cells with a dense electrolyte and porous electrodes could be co-fired successfully at $1325\sim1350^{\circ}C$ by controlling the contents of pore former and the ratio of coarse YSZ and fine YSZ in the anode and the cathode. The single cell co-fired at $1350^{\circ}C$ showed $100.2mWcm^{-2}$ of maximum power density at $800^{\circ}C$ but it was impossible to apply it to operate at low temperature because of low performance and high ASR, which were attributed to formation of the secondary phases in the cathode and the interface between the electrolyte and the cathode.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.889-892
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• 2000

We have investigated the Pt doping effect on structural and electrochemical properties of amorphous vanadium oxide film, grown by radio frequency magnetron sputtering. Room temperature charge-discharge measurements based on a half-cell with a constant current clearly indicated that the Pt doping could improve the cyclibility of V$_2$O$_{5}$ cathode film. Using glancing angle x-ray diffraction (GXRD) and high resolution transmission electron microscopy (HRTEM) analysis, we found that the Pt doping with l0W r.f. power induce more random amorphous structure than undoped V$_2$O$_{5}$ film. As the r.f. power of Pt increases, large amount of Pt incorporates into amorphous V$_2$O$_{5}$ and makes PtOx microcrystalline phase in amorphous matrix. This result suggests that the semicondcuting PtOx microcrystalline phase in amorphous matrix lead to a drastically faded cyclibility of 50W Pt doped V$_2$O$_{5}$ cathode film. Possible explanations are given to describe the Pt doping effect on cyclibility of vanadium oxide cathode film.de film.