• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.986-992
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• 2003

We have calculated the probability of the OH formation and energy deposit of the reaction exothermicity in the newly formed OH, particularly in its vibrational motion, in the gas-surface reaction O(g) + H(ad)/Si → OH(g) + Si on the basis of the collision-induced Eley-Rideal mechanism. The reaction probability of the OH formation increases linearly with initial excitation of the HSi vibration. The translational and vibrational motions share most of the energy when the H-Si vibration is initially in the ground state. But, when the initial excitation increases, the vibrational energy of OH rises accordingly, while the energies shared by other motions vary only slightly. The product vibrational excitation is significant and the population distribution is inverted. Flow of energy between the reaction zone and the solid has been incorporated in trajectory calculations. The amount of energy propagated into the solid is only a few percent of the available energy released in the OH formation.

• 한국결정성장학회지
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• 제26권5호
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• pp.181-187
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• 2016

본 연구에서는 납이나 크롬이 함유되지 않은 친환경적인 물질의 새로운 주황 무기 안료를 개발하고자 하였다. 고상반응법을 이용하여 LPG와 Air를 이용한 환원분위기에서 $TiO_2-SnO-ZnO$계 주황색 무기 안료를 합성하였다. 합성 된 안료들의 특성을 분석하기 위하여 표색계 값인 $L^*a^*b^*$ 값을 측정 후, XRD를 이용하여 결정 상을 분석하였고, SEM을 이용하여 미세구조 관찰하였으며, XPS를 이용하여 원소들의 산화가 상태를 분석하였다. 고상 반응법으로 합성 후 열처리한 $TiO_2-SnO-ZnO$ 안료는 yellow에서 orange-red 사이의 색을 가진다. $TiO_2-SnO-ZnO$ 안료의 결정상 분석 결과, 5가지의 결정상이 혼재하는 것을 볼 수 있는데, $SnO_2$가 cubic과 tetragonal 구조 중 어떤 결정 구조를 가지는지가 발색의 가장 중요한 요인으로 작용하는 것을 확인하였다. XPS를 이용하여 원소들의 산화가 상태를 분석한 결과, $Sn^{4+}$의 비율이 높을수록 안료가 rYR에 가까운 색을 가지는 것을 확인할 수 있다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.342-342
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• 2012

Resistance-change Random Access Memory (ReRAM), which utilizes electrochemical control of nanoscale quantities of metal in thin films of solid electrolyte, shows great promise as a future solid state memory. The technology utilizes the electrochemical formation and removal of metallic pathways in thin films of solid electrolyte. Key attributes are low voltage and current operation, excellent scalability, and a simple fabrication sequence. In this study, we investigated the nature of thin films formed by photo doping of Ag+ ions into chalcogenide materials for use in solid electrolyte of programmable metallization cell devices. We measured the I-V characteristics by field-effect of the device. The results imply that a Ag-rich phase separates owing to the reaction of Ag with free atoms from chalcogenide materials.

• 한국세라믹학회지
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• 제29권5호
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• pp.377-382
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• 1992

For the development of solid oxide fuel cell the joined interface formation between perovskite oxygen electrode and YSZ solid electrolyte is emphasized in the aspect of reducing the undisirable overpotential. The diffusion couple of LaMnO3 and YSZ was prepared by hot pressing at 130$0^{\circ}C$ in the flow of oxygen gas. The high temperature solid state reaction mechanism between LaMnO3 and YSZ is discussed on the basis of the cation composition profile through EDX analysis. The cation components in perovskite compound diffuse considerably into YSZ, while cations of YSZ diffuse little into perovskite.

• Journal of Magnetics
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• 제16권2호
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• pp.101-103
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• 2011

Solid solutions between $BaTiO_3$ and $LaFeO_3$ have been prepared through a solid state reaction method. The X-ray diffraction results reveal that $Ba_{1-x}La_xTi_{1-x}Fe_xO_3$ ($0.1\;{\leq}\;x\;{\leq}\;0.7$) compounds have a cubic structure, whereas the parent material $BaTiO_3$ has a tetragonal structure. The magnetization measurements indicate that the materials have a magnetic ordering at room temperature and the magnetic properties of the solid solutions depending on the doping amount of $LaFeO_3$. The origin of magnetic behaviors is believed to be from $Fe^{3+}$ ions.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1996년도 The 9th KACG Technical Annual Meeting and the 3rd Korea-Japan EMGS (Electronic Materials Growth Symposium)
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• pp.5-18
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• 1996

The solid state cesium ion source os alumino-silicate based zeolite which contains cerium. The material is an ionic conductor. Cesiums are stably stored in the material and one can extract the cesiums by applying electric field across the electrolyte. Cesium ion bombardment has the unique property of producing high negative ion yield. This ion source is used as the primary source for the production of a negative ion without any gas discharge or the need for a carrier gas. The deposition of materials as an ionic species in the energy range of 1.0 to 300eV is recently recognized as a very promising new thin film technique. This energetic non-thermal equilibrium deposition process produces films by “Kinetic Bonding / Energetic Condensation" mechansim not governed by the common place thermo-mechanical reaction. Under these highly non-equilibrium conditions meta-stable materials are realized and the negative ion is considered to be an optimum paeticle or tool for the purpose. This process differs fundamentally from the conventional ion beam assisted deposition (IBAD) technique such that the ion beam energy transfer to the deposition process is directly coupled the process. Since cesium ion beam sputter deposition process is forming materials with high kinetic energy of metal ion beams, the process provider following unique advantages:(1) to synthesize non thermal-equilibrium materials, (2) to form materials at lower processing temperature than used for conventional chemical of physical vapor deposition, (3) to deposit very uniform, dense, and good adhesive films (4) to make higher doposition rate, (5) to control the ion flux and ion energy independently. Solid state cesium ion beam sputter deposition system has been developed. This source is capable of producing variety of metal ion beams such as C, Si, W, Ta, Mo, Al, Au, Ag, Cr etc. Using this deposition system, several researches have been performed. (1) To produce superior quality amorphous diamond films (2) to produce carbon nitirde hard coatings(Carbon nitride is a new material whose hardness is comparable to the diamond and also has a very high thermal stability.) (3) to produce cesiated amorphous diamond thin film coated Si surface exhibiting negative electron affinity characteristics. In this presentation, the principles of solid state cesium ion beam sputter deposition and several applications of negative metal ion source will be introduced.

• 반도체디스플레이기술학회지
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• 제6권4호
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• pp.29-32
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• 2007

Zinc gallate, $ZnGa_2O_4:Mn^{2+}$ co-doped with different concentrations of $Mg^{2+}$ (0.001- 0.5 mol%) was prepared by solid state synthesis method. These compositions were investigated for their photoluminescence and cathodoluminescence properties. The optimized composition $Zn_{0.990}Mg_{0.005}Ga_2O_4:Mn_{0.005}$ shows higher luminescence intensity compared to the parent phosphor. The intense green emission peak was found at 504 nm. The $Mg^{2+}$ doping does not affect much the decay time. It remains <10 ms for these compositions which make them potential candidate for application in TV screens.

• 한국진공학회지
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• 제2권4호
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• pp.507-514
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• 1993

The solid state reaction of Mo/Si multilayer thin films produced by RF magnetron sputtering technique was examine dusing differential scanning calorimetry (DSC) and x-ray diffraction, and explained in view of two concepts, effective drivig force and effective heat of formation. In constant scanning rate DSC, there were two exothermic peks which corresponded to the formation of h-MoSi2 and t-MoSi2 , respectively. The activation energyfor theformation of h-MoSi2 was 1.5eV , and that of t-MoSi2 was 7.8eV. Nucleation wa stherate controlling mechanism for each of the silicide formation. Amorphous phase was not formed , which was consistent withtheprediction by the concept of effective driving force. h-MoSi2 the first crystalline phase, was considered to have lower interfacial free energy than t-MoSi2 and by increasing temperature it was transformed into more stable t-MoSi2.

• 한국세라믹학회지
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• 제35권8호
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• pp.801-806
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• 1998

$Eu^{3+}$ -doped $Y_2$$O_3$ phosphors has been prepared by a polymerized complex method and investigated their powder and luminescence properties. They were compared with phosphors prepared by a solid state reac-thion method. The phosphors synthesized have been characterized by X-ray diffraction low-voltage lu-minescent emission spectroscopy etc. Under low-voltage electron excitation $Eu^{3+}$-doped $Y_2$$O_3$ exhibited a strong narrow-band red emission peaking at 612nm. On the other hand the critical value for concentration quenching of sample prepared by the polymerized complex method fired at $1400^{\circ}C$ is x=0.05 for $(Y_{1-x}Eu_x__2O_3$ The emission intensity of phosphors prepared by the polymerized complex method was higher than that of phosphors prepared by the solid state reaction method.

• Transactions on Electrical and Electronic Materials
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• 제13권3호
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• pp.121-124
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• 2012

Olivine type $LiFePO_4$ cathode material was synthesized by solid-state reaction method including one-step heat treatment. To improve the electrochemical characteristics, graphite nanofiber (GNF) was added into $LiFePO_4$ cathode material. The structure and morphological performance of $LiFePO_4$ were investigated by X-ray diffraction (XRD); and a field emission-scanning electron microscope (FE-SEM). The synthesized $LiFePO_4$ has an olivine structure with no impurity, and the average particle size of $LiFePO_4$ is about 200~300 nm. With graphite nanofiber added, the discharge capacity increased from 113.43 mAh/g to 155.63 mAh/g at a current density of 0.1 $mA/cm^2$. The resistance was also significantly decreased by the added graphite nanofiber.