• 전자공학회논문지A
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• 제33A권12호
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• pp.77-82
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• 1996

The breakdown characteristics of metal-oxide-semiconductor(MOS) capacitors fabricated by Al, polysilicon, and tungsten polycide gate electrodes onto gate oxide was evaluated by time zero dielectric breakdwon (TZDB). The average breakdown field of the gate oxide with tungsten polycide electride was lower than that of the polysilicon electrode. The B model (1~8MV/cm) failure of the gate oxide with tungsten polycide electrode was increased with increasing annealing temperature in the dry $O_{2}$ ambient. This is attributed ot fluorine and tungsten diffusion from thungsten silicide film into the gate oxide, and stress increase of tungsten polcide after annealing treatment.

• 한국세라믹학회지
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• 제36권9호
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• pp.991-996
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• 1999

Effect of solution property on the weight varation and microstructural change of film was studied by electrophoretic deposition in order to obtain a homogeneous and dense zirconia film. As a result of weight kinetics of film which obtained in alcohol or aqueous solution having different polarity experimental data showed large deviation from theoretical ones calculated by Zhang's kinetic model. It had been shown that the weight affecting factors was largely dependent on properties other than dielectric constant and viscosity of solvent zeta potential appiled field and time. In initial stage a main factor of the drastic weight increase was the capillary drag of porous substrate. The cause of weight decrease with time in aqueous solution after 300 s was attributed to the defect of film by sagging and electrolytic reaction. The electrolyte film which prepared in alcohol solution with good wetting for substrate had better homogeneous and dense microstructure than one in aqueous solution with high surface tension.

• 한국세라믹학회지
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• 제23권6호
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• pp.52-58
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• 1986

$Pb(Zr_{0.525} Ti_{0.475})O_3$ piezoelectric ceramics both unmodified and doped with NiO were prepared by the conventional oxide techniques using sintering temperature from 900 to to 125$0^{\circ}C$. The difference in densification process between unmodified and NiO doped PZT ceramics was studied by shrinkage vs. firing temperatures and it was caused by increasing defect concentration in calcining process of NiO doped PZT ceramics. And nickel oxide solubility limit for $Pb(Zr_{0.525} Ti_{0.475})O_3$ ceramics is shown to be at the range from 0.2wt% to 0.5wt% from this defect model micro-structures dielectric and piezolectric properties of Nio doped PZT ceramics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.234-234
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• 2008

Chemically homogeneous $Ba_{0.6}Sr_{0.4}TiO_3$ (BST) sols were synthesized using barium acetate, strontium acetate, and titanium isoproxide as starting materials. BST thin films of thickness 340 nm were deposited on Pt/$TiO_2/SiO_2$/Si and alumina substrates using spin coating method. The technique used for the processing of these films was Ultraviolet (UV) sol-gel photoannealing, using phto-sensitivity precursor solutions and UV-assisted rapid thermal processing(UV-RTP). The crystallization behaviour of the BST sols and thin films was studied by differential thermal analysis (DTA) and X-ray diffraction (XRD). Variation of permittivity and dielectric loss were measured in LCR-meter, model HP 4394A.

• 마이크로전자및패키징학회지
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• 제11권4호
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• pp.49-53
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• 2004

고분자 재료가 전자산업분야에서 절연재료나 접착제로 널리 사용되고 있다. 실리콘 기판위에 증착된 고분자 층에는 기판과의 열팽창계수 차이로 인해 열응력이 발생할 수 있다 고분자 층과 기판사이의 열적 성질의 차이로 인해 큰 잔류응력이 야기된다. 본 연구에서는 레이저 주사법을 이용하여 열적변형으로 인한 곡률변화를 측정한 후, 해석적 방법을 적용하여 수정된 박막 물성을 구하는 방법을 제시하고 있다.

• 전자공학회논문지A
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• 제32A권3호
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• pp.25-37
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• 1995

The phenomenological loss equivalence method incorporated into the wideband lossy transmission line model is applied to the characterization of high desity digital transmission lines. The pulse propagation characteristics are analyzed using the calculated frequency characteristics and the discrete Fourier transformation. This approach has been verified by comparing the calculated frequency characteristics with the FEM and the esperimental results. This method is very suitable for computer-aided analysis of high density/high speed interconnection circuits because of the simple calculation as well as the calculation accuracy. We have found that pulse ftransmission speed and dispersion of hgih density digital transmission lines can be optimized by managing the conductor and dielectric losses in addition to the impedance matching.

• 대한전자공학회논문지
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• 제26권2호
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• pp.35-40
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• 1989

본 논문에서는 균일한 유전체로 채워져 있고 윗면에 슬릿이 있는 평행평판 도파로의 ${\pi}-$ 등가회로로 부터 구형 마이크로스트립 안테나의 복사 컨덕턴스와 서셉턴스를 동시에 구하는 새로운 방법을 제시하였다. 계산된 결과를 기존의 이론치와 비교하였다. 또한 등가전송선로를 이용하여 반사손실(return loss) 및 공진주파수를 계산하여 실험치와 비교한 결과 양호한 특성을 얻었다.

• 한국소음진동공학회논문집
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• 제17권12호
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• pp.1179-1183
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• 2007

Electro-Active paper(EAPap) is a new smart material that has a potential to be used in biomimetic actuator and sensor. It is made by cellulose that is abundant material in nature. EAPap is fascinating with its biodegradability, lightweight, large displacement, high mechanical strength and low actuation voltage. Actuating mechanism of EAPap is known to be the combined effects of ion migration and piezoelectricity. However, the electromechanical actuation mechanisms are not yet to be established. This paper presents the modeling of the actuation behavior of water infused cellulose samples and their composite dielectric constants calculated by Maxwell-Wagner theory. Electro-mechanical forces were calculated using Maxwell stress tensor method. Bending deflection was evaluated from simple beam model and compared with experimental observation, and which result in good correlation with each other.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.72-74
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• 2014

Multilayer ceramic capacitor (MLCC) makes acoustic noise of electronic devices. Conversed piezoelectric effect of dielectric substance consists of $BaTiO_3$ causes vibration of MLCC so it must be analyzed to reduce the noise. Thus, finite element model for piezoelectric analysis of MLCC was constructed in this paper. Piezoelectric characteristics of MLCC was considered for the accurate simulation result. Displacement response for sinusoidal voltage signal was measured and simulation result was verified with test result.

• 한국전자파학회논문지
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• 제14권12호
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• pp.1264-1268
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• 2003

본 논문에서는 밀리미터파 대역에서 NRD guide를 이용한 듀플렉서를 설계하였다. 설계된 듀플렉서는 두개의 stepped-impedance 필터와 한 개의 T-Junction으로 구성되어 있다. 차단영역 도파관 등가회로를 이용하여 stepped-impedance 필터를 설계하였고, T-Junction은 반사손실을 -20 dB 이하로 최적화하였다. 듀플렉서를 제작하여 측정한 결과 응답특성이 시뮬레이션 결과와 일치함을 확인하였다.