• JSTS:Journal of Semiconductor Technology and Science
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• 제2권3호
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• pp.233-236
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• 2002

Some measures are provided for the optimum design of specific on-resistance $R_{on}$ and breakdown-voltage $V_B$ of interdigitated CB (Composite Buffer) MOSFET, including introducing opposite type impurity into the P region near the $N_＋$contact, separating P region from N region with an oxide film, and a groove in the N region near the $P_＋$ contact. The new relationship between the $R_{on}$ and $V_B$, which proved by numerical device simulation, are more exact and minute than the qualitative results before.

• 약학회지
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• 제38권2호
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• pp.131-139
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• 1994

Calcein-encapsulated small unilamellar vesicles of various lipid composition were prepared using the sonication technique, and their stabilities at $20^{\circ}C$ were examined by measuring calcein leakage from the liposomes. The fluidity of these liposomal bilayers was also investigated by measuring the fluorescence polarization of DPH labelled into the liposomes. The results showed that liposomes made of PC mixtures with different acyl chain length were very stable, which may be due to the formation of interdigitated bilayer structure. The addition of cholesterol further stabilized these PC liposomes. However, addition of cholesterol reduced the encapsulation efficiences of liposomes. The fluidity of the liposomes was significantly decreased by cholesterol in the liquid crystalline state, but not changed in the gel state. These results suggest that the enhanced stability of PC mixture liposomes may be ascribed to the formation of stable interdigitated bilayer structure. In membrane-mimetic and drug-delivery studies, vesicles made of mixtures of various phospholipids are recommended instead of addition of cholesterol to the phospholipid.

• ETRI Journal
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• 제28권2호
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• pp.182-190
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• 2006

The circuit modeling of interdigitated capacitors fabricated by high-k low-temperature co-fired ceramic (LTCC) sheets was investigated. The s-parameters of each test structure were measured from 50 MHz to 10 GHz, and the modeling was performed using these measured sparameters up to the first resonant frequency. Each test structure was divided into appropriate building blocks. The equivalent circuit of each building block was composed based on the partial element equivalent circuit (PEEC) method. Modeling was executed to optimize the parameters in the equivalent circuit of each building block. The validity of the extracted parameters was verified by the predictive modeling for the test structures with different geometry. After that, Monte Carlo analysis and sensitivity analysis were performed based on the extracted parameters. The modeling methodology can allow a device designer to improve the yield and to save time and cost for the design and manufacturing of devices.

• 한국소음진동공학회논문집
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• 제15권12호
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• pp.1408-1415
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• 2005

Active vibration control of smart hull structure using Macro Fiber Composite (MFC) actuator is performed. Finite element modeling is used to obtain governing equations of motion and boundary effects of end-capped smart hull structure. Equivalent interdigitated electrode model is developed to obtain piezoelectric couplings of MFC actuator. Modal analysis is conducted to investigate the dynamic characteristics of the hull structure, and compared to the results of experimental investigation. MFC actuators are attached where the maximum control performance can be obtained. Active controller based on Linear Quadratic Gaussian (LQG) theory is designed to suppress vibration of smart hull structure. It is observed that closed loop damping can be improved with suitable weighting factors in the developed LQG controller and structural vibration is controlled effectively.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.217-222
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• 2005

Active vibration control of smart hull structure using Macro Fiber Composite (MFC) actuator is performed. Finite element modeling is used to obtain governing equations of motion and boundary effects of end-capped smart hull structure. Equivalent interdigitated electrode model is developed to obtain piezoelectric couplings of MFC actuator. Modal analysis is conducted to investigate the dynamic characteristics of the hull structure, and compared to the results of experimental investigation. MFC actuators are attached where the maximum control performance can be obtained. Active controller based on Linear Quadratic Gaussian (LQG) theory is designed to suppress vibration of smart hull structure. It is observed that closed loop damping can be improved with suitable weighting factors in the developed LQG controller and structural vibration is controlled effectively.

• 한국산학기술학회논문지
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• 제20권6호
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• pp.604-609
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• 2019

본 논문에서는 열경화성 폴리이미드를 정전용량형 습도센서의 감습재료로 사용하여 공정이 간단한 IDT(Interdigitated) 전극을 갖는 정전용량형 습도센서를 제작하고 특성을 측정 및 분석하였다. 먼저 일정한 용량값을 얻기 위하여 용량형 센서의 전극 수, 전극의 두께와 간격 및 폴리이미드 감습막의 두께 등을 최적화하여 마스크 설계 및 제작을 했으며, 실리콘 기판 상에 반도체 공정 장비를 이용하여 정전용량형 습도센서를 제작하였다. 제작된 센서의 면적은 $1.56{\times}1.66mm^2$ 이며, 전극의 넓이와 전극간 폭은 동일하게 각각 $3{\mu}m$, 센서의 감도를 위해 전극 수를 166개, 전극의 길이는 1.294mm로 제작하였다. 그런 다음 센서 특성을 측정하기 위해 PCB상에 패키징 하였다. $25^{\circ}C$ 챔버 환경에 센서를 삽입하고 LCR Meter에 연결하여 1V, 20kHz를 인가한 상태에서 20%RH에서 90%RH까지 습도변화에 대한 용량값 변화를 측정하였다. 제작된 정전용량형 습도센서의 측정 결과 감도는 26fF/%RH, 선형 특성 < ${\pm}2%RH$ 그리고 히스테리시스는 < ${\pm}2.5%RH$를 얻을 수 있었다.

• 한국재료학회지
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• 제9권9호
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• pp.890-895
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• 1999

본 연구에서는 SOI 구조를 이용한 50$\mu\textrm{m}$ 두계의 규소 태양전지의 이용 가능성과 제한사항을 제시하기 위하여, interdigitated contact을 이용한 전극을 형성하도록 전지를 설계한 후 단계별 사진공정을 통해 태양전지를 제조하였다. Bonded SOI wafer를 이용하여 제조된 50$\mu\textrm{m}$ 두께의 결정질 규소 태양전지의 효율은 전극간격이 1100$\mu\textrm{m}$과 base width가 35$\mu\textrm{m}$인 경우에서 11.5%로 가장 높은 값을 나타내었다. 또한 실험결과로부터 전면전극을 이용한 태양전지의 구조는 power loss를 최소화하는 최적의 base fraction을 적용하는 것이 필요하며, 전지의 효율은 fill factor에 강한 의존성을 나타내기 때문에 fill factor loss를 최소화하는 설계조건이 필요함을 알 수 있었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권10호
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• pp.475-480
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• 2006

Vanadium oxide thin films (VOx) have been deposited by RF magnetron sputtering from $V_2O_5$ target under different oxygen partial pressure ratios(0%, 10%) and substrate temperatures$(27^{\circ}C,\;400^{\circ}C)$. Crystallographic structure and morphology of the films are studied by XRD and SEM. Humidity-sensing properties of resistive sensors having interdigitated electrode structure are characterized through electrical conduction measurements. The films deposited at room temperature are amorphous whereas the ones deposited above foot are polycrystalline. The sensors show good response to humidity over 20%RH to 80%RH. Vanadium oxide thin films deposited with $0%O_2$ partial pressure at $400^{\circ}C$ exhibit greater sensitivity to humidity change than others.

• Smart Structures and Systems
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• 제5권6호
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• pp.633-644
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• 2009

A simple method has been developed to detect the bonding condition of active fiber composites (AFC) adhered to the surface of a host structure. Large deformation actuating capability is one of important features of AFC. Edge delamination in adhesive layer due to large interfacial shear stress at the free edge is typically resulted from axial strain mismatch between bonded materials. AFC patch possesses very good flexibility and toughness. When an AFC patch is partially delaminated from host structure, there remains sensing capability in the debonded part. The debonding size can be determined through axial resonance measured by the interdigitated electrodes symmetrically aligned on opposite surfaces of the patch. The electrical impedance and modal response of the AFC patch in part adhered to an aluminum plate were investigated in a broad frequency range. Debonding ratio of the AFC patch is in inverse proportion to the resonant frequency of the fundamental mode. Feasibility of in-situ detecting the progressive delamination between AFC patch and host plate is demonstrated.

• Journal of Mechanical Science and Technology
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• 제20권4호
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• pp.505-512
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• 2006

This paper presents an integrated multifunctional sensor based on MEMS technology, which can be used or embedded in mobile devices for environmental monitoring. An absolute pressure sensor, a temperature sensor and a humidity sensor are integrated in one silicon chip of which the size is $5mm\times5mm$. The pressure sensor uses a bulk-micromachined diaphragm structure with the piezoresistors. For temperature sensing, a silicon temperature sensor based on the spreading-resistance principle is designed and fabricated. The humidity sensor is a capacitive humidity sensor which has the polyimide film and interdigitated capacitance electrodes. The different piezoresistive orientation is used for the pressure and temperature sensor to avoid the interference between sensors. Each sensor shows good sensor characteristics except for the humidity sensor. However, the linearity and hysteresis of the humidity sensor can be improved by selecting the proper polymer materials and structures.