http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이동 통신용 $BiNbO_4$ 세라믹스의 CuO 및 CdO 첨가량에 따른 고주파 유전 특성
윤중락,이헌용,김경용,Yun, Jung-Rak,Lee, Heon-Yong,Kim, Gyeong-Yong 한국재료학회 1998 한국재료학회지 Vol.8 No.11
CuO 및 C얘의 첨가가 $BiNbO_4$ 세라믹스의 고주파 유전특성에 미치는 영향을 조사하였다. CdO 첨가량이 증가함에 따라 소결밀도 및 품질계수는 감소하였고 소결온도가 증가하면 유전상수 및 품질계수는 증가하였다. $BiNbO_4$에 CuO 및 CdO를 각각 0.03wt% 첨가한 시편을 $960^{\circ}C$에서 소결시 유전율 41.2, 품질계수($Q{\times}f_0$) 6,500(at 5.6GHz), 공진주파수 온도계수 $3ppm^{\circ}C$의 우수한 고주파 유전특성을 얻을 수 있었다. The effect of CuO and CdO addition on the microwave dielectric properties of $BiNbO_4$, ceramics were investigated. As the content of CdO increased, sintered density and quality factor decreased. With increasing sintering temperature, both the dielectric constant and quality factor increased. In the case of specimen sintered at $960^{\circ}C$ with addition of 0.03 wt% of CuO and CdO, respectively. the microwave dielectric properties obtained were dielectric constant of 41.2, quality factor ($Q{\times}f_0$) of 6,500 (at 5.6GHz), temperature coefficient of resonant frequency of $3ppm^{\circ}C$.
윤중락,이창배,이경민,이헌용,이동희,Yoon, Jung-Rag,Lee, Chang-Bae,Lee, Kyong-Min,Lee, Heun-Young,Rhie, Dong-Hee 한국전기전자재료학회 2009 전기전자재료학회논문지 Vol.22 No.8
Lead-free piezoelectric ($Na_{1/2}K_{1/2}$)$NbO_3$ ceramics doped with CuO and $MnO_2$ were fabricated using the conventional oxide-mixing technique. With increasing content of CuO and $MnO_2$, the dielectric constant(${\varepsilon}_{33}$) and mechanical quality factor($Q_m$) value increased, while electromechanical coupling factor($K_p$) and piezoelectric constant($d_{33}$) decreased. The piezoelectric and dielectric properties ($Na_{1/2}K_{1/2}$)$NbO_3$ ceramics doped with CuO 2.461 wt% and $MnO_2$ 0.538 wt% at sintered temperature $1050\;^{\circ}C$ were attained ${\varepsilon}_{33}$ = 403, $K_p$ = 15, $Q_m$ = 122 and $d_{33}$ = 36 pC/N. Based on response surface methodology results using design of experiment, it was concluded that ($Na_{1/2}K_{1/2}$)$NbO_3$ doped with CuO 0.477 wt% and $MnO_2$ 0.269 wt% has possibility composition of being used for piezoelectric transformer.
Voltage Enhancement of ZnO Oxide Varistors for Various Y2O3 Doping Compositions
윤중락,이창배,이경민,이헌용,이석원 한국전기전자재료학회 2009 Transactions on Electrical and Electronic Material Vol.10 No.5
The microstructure and the electrical properties of a ZnO varistor, which was composed of a ZnO-Bi2O3-Sb2O3-CoO- MnO2 -NiO-Nd2O3 system, were investigated at various Y2O3 addition concentrations. Y2O3 played a role in the inhibition of the grain growth. As the Y2O3 content increased, the average grain size decreased from 6.8 ㎛ to 4 ㎛, and the varistor voltage(V1mA) greatly increased from 275 to 400 V/mm. The nonlinearity coefficient (α) decreased from 72 to 65 with increasing Y2O3 amount. On the other hand, the leakage current (IL) increased from 0.2 to 0.9 ㎂. These results confirmed that doping the varistors with Y2O3 is a promising production route for production of a higher fine-grained varistor voltage (V1mA) which can dramatically reduce the size of the varistors.
Dielectric Properties of Polymer-ceramic Composites for Embedded Capacitors
윤중락,이경민,이혜영,한정우,이헌용 한국전기전자재료학회 2009 Transactions on Electrical and Electronic Material Vol.10 No.4
Ceramic-polymer composites have been investigated for their suitability as embedded capacitor materials because they combine the processing ability of polymers with the desired dielectric properties of ceramics. This paper discusses the dielectric properties of the ceramic (BaTiO3)-polymer (Epoxy) composition as a function of ceramic particle size at a ceramic loading of 40 vol%. The dielectric constant of these ceramic-polymer composites increases as the powder size decreases. Results show that ceramic-polymer composites have a high dielectric constant associated with the BaTiO3 powder with a 200 nm particle size, high insulation resistance, high breakdown voltage (> 22 KV/mm), and low dielectric loss (0.018-0.024) at 1 MHz.
고압 적층 칩 캐패시터의 유전체 두께 및 내부전극 형상에 따른 AC, DC 절연 파괴 특성
윤중락,김민기,이석원,Yoon, Jung-Rag,Kim, Min-Kee,Lee, Seog-Won 한국전기전자재료학회 2008 전기전자재료 Vol.21 No.12
High voltage multilayer ceramic capacitors (MLCCs) are classified into two classes-those for temperature compensation (class I) and high dielectric constant materials (class II). We manufactured high voltage MLCC with temperature coefficient characteristics of C0G and X7R and studied the characteristics of electric properties. Also we studied the characteristics of dielectric breakdown voltage (V) as the variation of thickness in the green sheet and how to pattern the internal electrodes. The dielectric breakdown by electric field was caused by defects in the dielectric materials and dielectric/electrode interface, so the dielectric thickness increased, the withstanding voltage per unit (E) thickness decreased. To overcome this problem, we selected the special design like as floating electrode and this design affected the increasing breakdown voltage(V) and realized the constant withstanding voltage per unit thickness(E). From these results, high voltage application of MLCCs can be expanded and the rated voltage can also be develop.
(Ba,Ca)(TiZr)O3 세라믹을 적용한 적층 칩 커패시터의 전기적 특성
윤중락,여동훈,이헌용,이석원 대한전기학회 2006 전기학회논문지C Vol.55 No.1(C)
- The effect of A/B mol ratios and sintering temperatures on dielectric properties and microstructure of (Ba0.93Ca0.07)m(Ti0.82Zr0.18)O3 ceramics were investigated. The dielectric constant decreased with increasing the A/B mol ratio. However, the dielectric loss is improved. As the dielectric properties of A/B mol ratio with m = 1.009 at sintered temperature 1260℃, we obtained dielectric constant 12,800, dielectric loss 3.5% and Y5V temperature characteristics. Highly reliable Ni-MLCCs, 1.6mm (length) 0.8mm (width) 0.8mm (height) with capacitance of 1.23 μF and dissipation loss of 5.2% were obtained employing dielectric material composed of (Ba0.93Ca0.07)1.009(Ti0.82Zr0.18)O3 - MnO2 0.2wt% - Y2O3 0.18wt%, - SiO2 0.15wt% - (Ba0.4Ca0.6)SiO3 1 wt%.
실험계획법을 적용한 X7R 적층 칩 커패시터의 희토류(Y<sub>2</sub>O<sub>3</sub>, Er<sub>2</sub>O<sub>3</sub>) 첨가에 따른 전기적 특성
윤중락,문환,이헌용,Yoon, Jung-Rag,Moon, Hwan,Lee, Heun-Young 한국전기전자재료학회 2010 전기전자재료학회논문지 Vol.23 No.3
Employing statistical design of experiments, the difference in doping behaviors of rare-earth ions and their effects on the dielectric property and microstructure of $BaTiO_3$-MgO-$MnO_2$-($Ba_{0.4}Ca_{0.6}$) $SiO_3-Re_2O_3$ (Re = $Y_2O_3$, $Er_2O_3$) system were investigated. Through the statistical analysis we have found that the amount of $Re_2O_3$ are significantly affecting on the dielectric properties. The $Re_2O_3$ improved the dielectric constant, dielectric loss and R*C constant, so the appropriate contents of $Y_2O_3$ and $Er_2O_3$ were 0.8 ~ 1.2 mol% and 0.8 ~ 1.3 mol%, respectively. The MLCC(mutilayer chip capacitor) with $2.0{\times}1.2{\times}1.2mm$ size and 475 nF was also suited for X7R with the above composition. It showed that the dielectric constant and RC constant were 2,839 and 3,675 ${\Omega}F$, respectively in the sintering condition at $1250^{\circ}C$ in $Po_2$ $10^{-7}$ Mpa.
윤중락,이창배,이경민,이헌용,이석원 한국전기전자재료학회 2010 Transactions on Electrical and Electronic Material Vol.11 No.3
(1-X) (Na0.5K0.5)NbO3-X K4CuNb8O23 (NKN-X KCN) ceramics were produced using the conventional solid state sintering method, and their sinterability and electric properties were investigated. The density, dielectric constant (εr), piezoelectric constant d33, electromechanical coupling factor kp and mechanical quality factor Qm value of the NKN ceramics depended upon the KCN content and the sintering temperature. In particular, the KCN addition to the NKN greatly improved the mechanical quality factor Qm value. The ceramic with X = 2.0 mol% sintered at 1,150°C possesses the optimum properties (εr= 241, d33= 78, kp= 0.34 and Qm= 1,121). These results indicate that the ceramic is a promising candidate material for applications in lead free piezoelectric transformer and filter materials.
$(Na_{1/2}{\;}La_{1/2})TiO_3$ 세라믹스의 고주파 유전특성
윤중락,홍석경,김경용,Yun, Jung-Rag,Hong, Suk-Kyung,Kim, Kyung-Yong 한국재료학회 1993 한국재료학회지 Vol.3 No.5
Microwave dielectric properties of $(Na_{1/2}{\;}La_{1/2})TiO_3$ (NLT) ceramics which is an A site complex perovskite structure are investigated. Dense sintered bodies are obtained when calcined at $1000^{\circ}C$ for 4h and then sintered in the temperature range between $1350^{\circ}{\;}and{\;}1450^{\circ}C$. NLT shows the bulk density of $4.95g/\textrm{cm}^3$, relative density of 96.4%, and a simple cubic structure with lattice constant(a) of 3.873$\AA$. Dielectric Constant(${\varepsilon}_r$) and quality factor Q increase as bulk density and average grain size increase respectively. NLT has the dielectric ${\varepsilon}_r=125$, Q=2842(fo=3 GHz), ${\tau}_f=465{\;}ppm/^{\circ}C$ when sintered at $1400^{\circ}C$ for 4h. A site 복합 페로브스카이트 구조인 $(Na_{1/2}{\;}La_{1/2})TiO_3$ 세라믹스의 고주파 유전특성을 조사하였다. $1000^{\circ}C$에서 4시간 하소하고 $1350^{\circ}{\;}~{\;}1450^{\circ}C$에서 소결했을 때 치밀한 소결체가 되었다. NLT의 겉보기 밀도는 $4.95g/\textrm{cm}^3$, 상대밀도는 96.4%였으며, 격자상수(a)가 $3.873{\AA}$인 단순 입방정 구조였다. NLT의 유전율은 밀도가 높아짐에 따라 증가하였고 품진계수 Q는 평균 결정립 크기가 커짐에 따라 증가하였다. $1400^{\circ}C$에서 4시간 소결한 NLT는 ${\varepsilon}_r=125$, Q=2842(fo=3 GHz), ${\tau}_f=465$의 유전특성을 나타내었다.
압전변압기를 이용한 압전인버터 모듈 제작 및 전기적 특성
윤중락,이창배,우병철,Yoon, Jung-Rag,Lee, Chang-Bae,Woo, Byong-Chul 한국마이크로전자및패키징학회 2009 마이크로전자 및 패키징학회지 Vol.16 No.1
CCFL 구동용 인버터 모듈 개발을 위해, 내부전극 층수에 따른 Rosen-type 적층형 압전변압기를 제작하였으며, 내부전극 층수에 따른 출력 및 효율을 분석하였다. 압전변압기용 원료로는 PZT계 상용원료를 사용하였으며 구동회로는 Half-bridge 방식을 적용하여 압전인버터 모듈을 제작하였다 제작된 압전인버터 모듈의 입력전압은 12.5 V이고 스위칭 주파수는 104.3 KHz로서 압전인버터 구동시 약 100배의 승압비를 얻었으며, 효율은 87%이다. In order to develop piezoelectric inverter module for CCFL driving, Rosen-type multilayer piezoelectric transformer was fabricated. The output power and efficiency of mutilayer piezoelectric transformer according to the variation inner electrode layer were investigated. Mutilayer piezoelectric transformer was fabricated conventional mutilayer ceramic method using PZT base ceramics. Also, piezoelectric inverter module was adopted driving circuit with half-bridge type. The piezoelectric inverter module was set up with input voltage 12.5 V, switching frequency 104.3 KHz. The results showed the value of step-up ratio 100, efficiency 87% at load resistance of $100k{\Omega}$.