• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.16-17
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• 2006

In this paper, Ni-V alloy was studied with different structures and thickness. In case of Ni-V and Ni-V/Co/TiN, low resistive Ni silicide was formed after one step RTP (Rapid Thermal Process) with temperature range from $400^{\circ}C$ to $600^{\circ}C$ for 30sec in vacuum. After furnace annealing with temperatures range from $550^{\circ}C$ to $650^{\circ}C$ for 30min in nitrogen ambient, Ni-V single structure shows the best thermal stability compare with the other ones. To enhance the thermal stability up to 650oC and find the optimal thickness of Ni silicide, different thickness of Ni-V was studied in this work. Stable sheet resistance was obtained through Ni-V single structure with optimal Ni-V thickness.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.228-229
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• 2006

본 연구에서는 초음파 모터 등의 고출력 액츄에이터에 응용 가능한 $04Pb(Ni_{1/3}Nb_{2/3})O_3-6Pb(Zr_xTi_{1-x})O_3$ 조성시스템에 소결온도를 달리하여 압전, 유전특성 및 미세구조에 관해 고찰하였다. 본 조성을 $1200^{\circ}C$ 온도에서 2, 4, 6, 8시간 소결하여 시편을 제조하였으며 이의 결정구조 및 미세조직을 분석하였다. 소결시간 증가에 따라 전기기계결합계수와 기계적품질계수는 증가하였으며, 압전상수는 Zr(Zr+Ti)비 0.390까지 증가하였으나 그 이상 증가함에 따라 감소하였다. 압전특성은 $1200^{\circ}C$에서 4시간 소결한 Zr=0.390인 조성에서 ${\varepsilon}_r$ = 4487, $k_p$ = 0.72. $d_{33}$ = 710, $Q_m$ =109의 우수한 특성을 나타내었다.

• 대한치과교정학회지
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• 제41권6호
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• pp.399-410
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• 2011

본 연구의 목적은 코팅된 호선, 다양한 브라켓, 그리고 브라켓-호선 각도가 교정용 호선이 브라켓을 활주 이동하는 동안 발생되는 마찰력에 어떠한 영향을 미치는지에 대하여 평가해보는 것이었다. 고정식 장치를 이용한 교정치료 시발생할 수 있는 상황을 시뮬레이션하기 위하여 4종류의 브라켓(금속 브라켓인 Micro-arch, 단결정 세라믹 브라켓인 Perpect Clear2, active type의 자가결찰 브라켓인 Clippy-C, passive type의 자가결찰 브라켓인 Damon3)과 5종류의 교정용 호선(0.014", 0.016", 0.016" ${\times}$ 0.022" inch coated Ni-Ti 호선, 0.016", 0.016" ${\times}$ 0.022" inch Ni-Ti 호선)이 사용되었고 브라켓-호선 각도는 각각 $0^{\circ}$, $3^{\circ}$, $6^{\circ}$, $9^{\circ}$로 조절되었다. 모든 실험군에서 자가결찰 브라켓군, Micro-arch군, Perpect Clear2이 순으로 정지, 운동 마찰력이 유의하게 높았다 ($p$ < 0.001). $0^{\circ}$와 $3^{\circ}$의 브라켓-호선 각도에서 같은 크기의 Ni-Ti 호선은 코팅 여부에 따른 정지, 운동 마찰력의 유의한 차이가 없었으나, $3^{\circ}$에서 자가결찰 브라켓군의 0.016" ${\times}$ 0.022" inch Ni-Ti 호선에서만 코팅된 경우에 마찰력이 유의하게 높았으며 ($p$ < 0.001), $6^{\circ}$와 $9^{\circ}$의 브라켓-호선 각도에서 원형과 각형 호선은 모두 같은 크기의 코팅된 호선에서 정지, 운동 마찰력이 유의하게 높았다 ($p$ < 0.001). 코팅된 호선은 크기가 커질수록 정지, 운동 마찰력이 유의하게 높아졌다 ($p$ < 0.001). 각형 호선은 원형 호선 보다 정지, 운동 마찰력이 유의하게 높았으나, $9^{\circ}$의 브라켓-호선 각도에서 0.016" inch coated Ni-Ti 호선만은 0.016" ${\times}$ 0.022" inch Ni-Ti 호선보다 마찰력이 높았다 ($p$ < 0.001). 브라켓-호선 각도가 증가함에 따라 정지, 운동 마찰력도 유의하게 높아졌으나 ($p$ < 0.001), Micro-arch군과 Perpect Clear2군에서 0.016 inch Ni-Ti 호선과 이루는 각도 $0^{\circ}$, $3^{\circ}$에서는 마찰력의 유의한 차이가 없었다.

• Transactions on Electrical and Electronic Materials
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• 제9권2호
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• pp.47-51
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• 2008

In this paper, thermal stability of Nickel silicide formed on p-type silicon wafer using Ni-V alloy film was studied. As compared with pure Ni, Ni-V shows better thermal stability. The addition of Vanadium suppresses the phase transition of NiSi to $NiSi_2$ effectively. Ni-V single structure shows the best thermal stability compared with the other Ni-silicide using TiN and Co/TiN capping layers. To enhance the thermal stability up to $650^{\circ}C$ and find out the optimal thickness of Ni silicide, different thickness of Ni-V was also investigated in this work.

• 한국전기전자재료학회논문지
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• 제19권2호
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• pp.176-180
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• 2006

[ $(Na_{0.5}Bi_{0.5})TiO_3$ ][NBT] thin films were prepared on a highly (100) oriented $LaNiO_3[LNO]$ by sol-gel process. X-ray diffraction patterns of the NBT films annealed above $600^{\circ}C$ for 5 minutes have confirmed a highly (100) oriented growth and pseudocubic structure (a=3.884${\AA}$). The (l00) orientation factor increased from 90 to $99\%$ with increasing soaking time from 5 to 60 minutes at $600^{\circ}C$. The NBT films ($600^{\circ}C$/5 min,) have a flat and dense microstructure with large columnar grains, and their grain size are about 44 nm. The Au/NBT/LNO/Si hetero structure sample show a ferroelectric properties.

• 한국세라믹학회지
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• 제45권4호
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• pp.220-225
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• 2008

Lead-free ferroelectric ceramics are widely researched today for industrial applications as sensors, actuators and transducers. Since $Pb(Zr_aTi_{1-a})O_3$-(PZT) has high Curie temperature($T_C$), high piezoelectric properties near its morphotropic phase boundary(MPB) composition and small temperature dependence electrical behavior, it has been used to commercial materials for wide temperature range and different application fields. According to the tolerance factor concept, since the $Bi^{3+}$ cation with 12-fold coordinate has a smaller ionic radius than 12-fold coordinate $Pb^{2+}$, most bismuth based perovskites possess a smaller tolerance factor. Therefore, MPBs with a higher $T_C$ may be expected in $Bi(Me^{3+})O_3PbTiO_3$ solid solutions. As in lead based perovskite systems, it is clear that we need to explore more materials in simple or complex bismuth based MPB systems. The objective of this study is to investigate the $Bi(Ni_{1_a}X_a)O_3-PbTiO_3(X=Ti^{4+},\;Nb^{5+})$ perovskite solid-solution. For improving the electronic conduction problem, the magnesium and manganese modified system was also studied.

• 한국세라믹학회지
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• 제41권12호
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• pp.884-888
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• 2004

Effects of NiO were studied in aspects of dielectric properties and microstructure of $0.96(0.91Pb(Mg_{1/3}Nb_{2/3})O_3-0.09PbTiO_3)­0.04BaTiO_3$ (PMN-PT-BT, PBT). The PBT was prepared by a conventional mixed oxide method using $(MgCO_3)_4{\cdot}Mg(OH)_2$ instead of MgO through Lewis acid-base interaction. NiO was added in the range of 0.5 to $3.0\;wt\%$ as thermally decomposable $2NiCO_3{\cdot}3Ni(OH)_2$ and it seemed to enhance densification to a large extent below $1000^{\circ}C$. But all the systems gave rise to ceramics with almost same relative sintered density of 96% by sintering at $1000^{\circ}C$ for 2 h. But it turned out that the addition of NiO was detrimental to dielectric constant but beneficial to the loss of dielectric constant.

• 한국수소및신에너지학회논문집
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• 제18권3호
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• pp.325-333
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• 2007

[ $LiNi_{0.995}Al_{0.005}O_2$ ], $LiNi_{0.990}Ti_{0.010}O_2$ and $LiNi_{0.0990}Al_{0.005}Ti_{0.005}O_2$ were synthesized with a combustion method by calcining in an $O_2$ stream at $750^{\circ}C$ for 36 h. The X-ray diffraction patterns of these synthesized samples showed $-NaFeO_2$ structure of rhombohedral system(space group; $R{\bar{3}}\;m$) with no evidence of impurities. Among these samples, $LiNi_{0.995}Al_{0.005}O_2$ exhibited comparatively high first discharge capacity and discharge capacity, and the best cycling performance. $LiNi_{0.995}Al_{0.005}O_2$ had the first discharge capacity of 165.2 mA h/g and a discharge capacity of 116.7 mA h/g at the 50th cycle at 0.1C rate. It showed the first discharge capacity of 141.0 mA h/g and a discharge capacity of 93.5 mA h/g at the 50th cycle at 0.5C rate.

• 한국전기전자재료학회논문지
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• 제19권10호
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• pp.935-941
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• 2006

In this paper, the dielectric and piezoelectric properties of $0.4Pb(Ni_{1/3}Nb_{2/3})O_3+0.6Pb(Zr_{405}Ti_{595})O_3+X\;wt%\;Fe_2O_3$ ceramics were investigated with the addition of $Fe_2O_3$ and sintering temperature. Dielectric constant and piezoelectric constant increased with amount of $Fe_2O_3$ to 0.25 wt% and then decreased the further addition of $Fe_2O_3$. It seems that $Fe_2O_3$ acts as a sintering aid at the sintering temperature of $1150^{\circ}C$. By the addition of $Fe_2O_3$., sintering temperature of the system was lowered from $1250^{\circ}C\;to\;1100^{\circ}C$. The piezoelectric properties showed the maximum value of ${\varepsilon}r=4669,\;d_{33}=810(10^{-12}m/V)$, kp = 77 %, Qm = 55, in $0.4Pb(Ni_{1/3}Nb_{2/3})O_3\;-0.6Pb(Zr_{0.405}Ti_{0.595})O_3+0.25wt%\;Fe_2O_3$ ceramics having composition near the morphotropic phase boundary. The composition may be appropriate for actuator materials because of high piezoelectric constant and electromechanical coupling factor.

• 한국수소및신에너지학회논문집
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• 제5권2호
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• pp.73-79
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• 1994

The hydrogenation behavior of Ti-Ni powders prepared by mechanical alloying in a high energy ball mill have been investigated by P-C isotherm curves, DSC(differential scanning calorimetry), X-ray diffractometer, SEM(scanning electron microscope). Amorphous TiNi phase was formed after 10 milling hours. The hydrogen storage capacity gradually decreased as a function of mechanical alloying time. There appears the DSC endothermic peak due to hydrogen evolution of amorphous hydride phase.