• 한국전기전자재료학회논문지
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• 제24권11호
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• pp.895-899
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• 2011

Multiferroic BFO/PZT(5/95) multilayer films were fabricated by spin-coating method on the Pt/Ti/$SiO_2$/Si substrate alternately using BFO and PZT(9/95) alkoxide solutions. The structural and dielectric properties were investigated with variation of the solvent and the number of coatings. All films showed the typical XRD patterns of the perovskite polycrystalline structure without presence of the second phase such as $Bi_2Fe_4O_3$. BFO/PZT multilayer thin films showed the typical dielectric relaxation properties with increase an applied frequency. The average thickness of 6-coated BFO/PZT multilayer film was about 600 nm. The dielectric properties such as dielectric constant, dielectric loss and remnant polarization were superior to those of single composition BFO film, and those values for BFO/PZT multilayer film were 1199, 0.23% and 12 ${\mu}C/cm^2$.

• 센서학회지
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• 제24권4호
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• pp.219-223
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• 2015

Indium free consisting of three alternating layers GTO/Ag/GTO has been fabricated by radio-frequency (RF) sputtering for the applications as transparent conducting electrodes and the structural, electrical and optical properties of the gallium tin oxide (GTO) films were carefully studied. The gallium tin oxide thin films deposited at room temperature are found to have an amorphous structure. Hall Effect measurements show a strong influence on the conductivity type where it changed from n-type to p-type at $700^{\circ}C$. GTO/Ag/GTO multilayer structured electrode with a few nm of Ag layer embedded is fabricated and show the optical transmittance of 86.48% in the visible range (${\lambda}$ = 380~770 nm) and quite low electrical resistivity of ${\sim}10^{-5}{\Omega}cm$. The resultant power conversion efficiency of 2.60% of the multilayer based OPV (GAG) is lower than that of the reference commercial ITO. GTO/Ag/GTO multilayer is a promising transparent conducting electrode material due to its low resistivity, high transmittance, low temperature deposition and low cost components.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제34회 추계학술대회 개최
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• pp.78-87
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• 2001

The friction and wear behaviors of WC/C multilayer coating were investigated by using a pin on disk type tester. The experiment was conducted by using silicon nitride (S $i_{3}$ $N_{4}$) as a pin material and WC/C multilayer coating on bearing steel (STB2) as a disk material, under various environments that are atmospheric conditions of high vacuum( 1,3$\times$10$^{-4}$ Pa), medium vacuum( 1.3$\times$10$^{-l}$Pa). ambient air( 10$^{5}$ pa)(3 types) and relative humidity(2~98%) conditions. The results showed that WC/C coating fracture was suddenly increased with increasing degree of vacuum, because of high adhesion. So, WC/C coating could not be displayed their ability as solid lubricant. WC/C coating could be displayed better abilitv as solid lubricant with increasing relative humidity. because of oxide film, size and shape of wear debris. The friction coefficient and specific wear rate became better about RH 50%.%.

• 분석과학
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• 제8권4호
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• pp.591-596
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• 1995

Enzyme multilayers composed of avidin and biotin-labeled enzymes were prepared on the surface of electrode, through a strong affinity between avidin and biotin (binding constant: ca $10^{15} M^{-1}$). The enzyme multilayers were useful for the improvement of the performance characteristies of enzyme sensors. The output current of the enzyme sensors depended linearly on the number of enzyme layers deposited. Thus, lactate oxidase (LOx) and alcohol oxidase (AlOx) were deposited after being modified with biotin for constructing enzyme sensors sensitive to L-lactate and ethanol respectively. It was also possible to deposit two different kinds of enzymes successively in a single multilayer. The glucose oxidase (GOx) and ascorbate oxidase (AsOx) were built into a multilayer structure on a Platinum electrode. The GOx, AsOx multilayer-modified electrode was useful for the elimination of ascorbic acid interference of the glucose sensor.

• 센서학회지
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• 제9권1호
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• pp.76-82
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• 2000

본 연구에서는 내부전극 접합기술을 이용하여 적층구조의 PTC 서미스터를 제작하였다. 적층구조 PTC 서미스터는 저항, 소형, 대전류 등의 특징을 갖는다. PTC 특성을 조사하기 위하여 첨가제효과, 전압-전류특성, 온도특성, 복합임피던스 특성 등을 측정하였다. 적층구조 PTC서미스터는 저항의 온도특성과 전압-전류특성에서 높은 비선형성을 나타내었다. 적층수가 증가함에 따라 상온저항이 감소되는 특성이 결정립의 효과에 기인됨을 알았다. 전류의 스윗칭 변화는 적층구조가 갖는 열용량의 크기에 비례하였으며, 적층수가 증가할수록 스윗칭 시간이 증가하였다.

• 센서학회지
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• 제22권2호
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• pp.105-110
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• 2013

We fabricated an a-IGZO thin film transistor (TFT) with AZO/Ag/AZO transparent multilayer source/drain contacts by rf magnetron sputtering. a-IGZO TFT with AZO/Ag/AZO multilayer S/D electrodes (W/L = 400/50 ${\mu}m$) showed a subs-threshold swing of 3.78 V/dec, a minimum off-current of $10^{-12}$ A, a threshold voltage of 0.41 V, a field effect mobility of $10.86cm^2/Vs$, and an on/off ratio of $9{\times}10^9$. From the ultraviolet photoemission spectroscopy, it was revealed that the enhanced electrical performance resulted from the lowering of the Schottky barrier between a-IGZO and Ag due to the insertion of an AZO layer and thus the AZO/Ag/AZO multilayer would be very appropriate for a promising S/D contact material for the fabrication of high performance TFTs.

• 한국전자파학회논문지
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• 제13권3호
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• pp.301-307
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• 2002

본 논문에서는 종래 세라믹 칩 안테나의 단점인 협대역 특성을 개선하기 위해 헬리컬 구조를 갖는 적층형 세라믹 칩 안테나의 인덕턴스가 대역폭 향상에 미치는 영향을 3D 구조 시뮬레이션 결과에 의해 고찰하였다. 적층형 세라믹 칩 안테나를 고주파 구조 시뮬레이터인 HFSS에 의해 설계하였고, LTCC-MLC 공정 기술을 이용하여 유전 특성이 $\varepsilon$$_{r}$=7.8, tan $\delta$=0.0043인 유전체로 구현하였다. 또한, IMT-2000용 단말기에 적용 가능성을 보기 우하여 그 운용 주파수 (1,920~2,170 GHz)대에 설계된 안테나 제작하여, 주파수 응답 특성 및 복사 특성을 측정하였다.

• 융합신호처리학회논문지
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• 제9권3호
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• pp.238-244
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• 2008

동적 신경망은 temporal 신호처리가 요구되는 여러 분야에 사용되어 왔다. 본 논문에서는 다층 신경망의 동특성을 향상시키기 위해 감마 신경망(GAM) 다루고 있다. GAM 신경망은 순방향 다층 신경망의 히든층에 감마 메모리 커널을 사용하고 있다. GAM 신경망은 선형 및 비선형 시스템 식별을 통해 평가되었으며 상대적인 성능평가를 위해 순방향 신경망(FNN)과 리커런트 신경망(RNN)과 비교하고 있다. 실험결과에 의하면 GAM 신경망은 학습속도와 정확도에서 더 우수하게 동작하였으며, 이러한 사실은 시스템 식별에 있어서 GAM 신경망이 기존의 다른 다층 신경망보다 더 효과적인 신경망이 될 수 있음을 보여주었다.

• 산업기술연구
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• 제25권A호
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• pp.157-162
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• 2005

In this study, the fabrication of PZT films was performed from a multilayer structure comprising $TiO_2$, $ZrO_2$ and PbO thin films prepared by rapid themal chemical vapor deposition(RTMOCVD). $TiO_2$, $ZrO_2$ and PbO are the component layers of oxide multilayer system for a single phase PZT thin film. The composition control of PZT thin film was done by the thickness control of individual component layer. The composition ratio of Pb:Ti:Zr with thickness were 1:0.94:0.55. Occurrence of a single-phase of PZT was initiated at around $550^{\circ}C$ and almost completed at $750^{\circ}C$ under the fixed time of 1hr. As the concentration of Pb increased, the roughness and crystallization in the film increased. From the as result of using XPS and TEM, the single phase formation through annealing is evident. The electrical properites of the prepared PZT thin film(Zr/Ti=40/60, 300 nm) on a Pt-coated substrate were as follow: dielectric constant ${\varepsilon}_r=475$, coercive field Ec=320 kV/cm, and remanant polarization $P_r=11{\mu}C/cm^2$ at an applied voltage of 18 V.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1794-1796
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• 2000

Oxides of the form $Mn_{3}O_4$-$Co_{3}O_4$-NiO present properties that make them useful as multilayer chip NTC thermistor for mobile communication telephone. When $Mn_{2}Ni_{x}CO_{1-x}O_4$ composition with the X = 0.12$\sim$0.24 at sintered temperature 1250$^{\circ}C$, resistivity and B-constant were 300$\sim$450[${\Omega}-cm$] and 3250$\sim$3450, respectively. Multilayer chip NTC(Negative Temperature Coefficient) resistor were fabricated with 4 layer by a conventional multilayer capacitor techniques, using 100 pd paste as internal electrode and $Mn_{2}Ni_{0.20}CO_{0.8}O_4$ composition as NTC materials. In particular, resistance change ratio (${\Delta}R$), the important factor for reliability, varied within $\pm$3%, indicating the compositions of multilayer chip NTC thermistor products could be available for mobile communication telephone.