• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1209-1212
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• 1995

This paper presents a capacitive humidity sensor using porous silicon layers formed tom the anodization of p-type silicon in HF solution. The upper electrodes consist of many aluminum strips over porous silicon, between which the porous silicon is etched away. The sensor showed a good sensitivity(20pF/%RH) and lineaity in the range of 40%RH$\sim$80%RH, a hysteresis of ${\pm}2%$ RH, and a slow transient response. These preliminary resluts show that futher improvement can still be expected.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.30.2-30.2
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• 2011

나노 채널 구조는 반응 물질의 빠른 확산 경로를 제공하고, 넓은 반응 활성화 면적을 가지므로, 센서, 촉매, 전지 등의 다양한 기능성 전기 화학 소자용 고효율 전극 구조로서 관심을 받고 있다. 최근 양극 산화법을 이용하여, 자가 배열된 나노 채널 구조의 주석 산화물을 형성시키는 연구가 진행되고 있다. 그러나, 기재위에 도금된 주석 박막이 양극 산화에 의해 산화물로 변화하는 과정에서 내부 균열 및 표면 기공의 막힘 현상이 관찰되고, 기재 위 주석의 산화가 완료되는 시점에서는 기재의 산화 및 산소 발생에 의한 기계적 충격 등으로 인해 산화물이 기재로부터 탈리되는 문제가 발생하여, 그 응용 연구가 크게 제한되어 있는 실정이다. 본 연구에서는 다공성 주석 산화물 합성 시의 구조적 결함이 나타나는 이유에 대해 체계적으로 분석하고, 이를 바탕으로 결함이 없는 나노 채널 주석 산화물을 제조하는 방법을 제시하였다. 또한, 주석 산화물 박막을 기능성 전기화학 소자용 전극 활물질, 특히 리튬 전지용 음극재료로 사용하기 위한 효과적인 전극 제조 방법에 대해 논의하고, 그에 따라 제조된 전극의 충방전 용량, 사이클링 안정성 등을 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
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• pp.125-126
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• 2008

A differential capacitance deviation-to-time converter for interfacing position sensor is presented. It consists of triaxial position sensor, six comparators, six current mirrors, and control logic. The prototype differential capacitance deviation-to-time interval converter has been simulated using Chartered $0.35-{\mu}m$ CMOS parameters. The simulation results show that the maximum conversion time of the converter is $350{\mu}s$ and the linearity error is less than ${\pm}0.00l5%$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.1773-1774
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• 2006

나노 기술의 급격한 발달에 따라 나노미터 수준의 정밀도를 갖는 초정밀 측정 기술이 여러 분야에서 요구되고 있다. 헤테로다인 레이저 간섭계를 이용하여 초정밀 위치 측정을 하려고 할 때, 광학기기 자체의 불완전함에서 발생하는 비선형성 오차는 주요한 요소로 작용한다. 본 논문에서는 헤테로다인 레이저 간섭계 시스템에서의 비선형성을 보정해주기 위해 적응형 알고리즘을 제안한다. 기준 입력인 정전용량센서와 최소자승법을 이용하여 보정변수를 구한 후, 반복 최소자승법을 이용하여 비선형성에 따른 타원 위상을 비선형성이 보정된 원 위의 위상으로 사상시킨다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2537-2539
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• 2005

In many cases the systems are so complex that it is not possible to obtain reasonable models using physical laws. Also a model based on physical laws contains a number of unknown parameters even if the structure is derived from physical laws. These problems can be solved by system identification. In this paper, a nano stage system is selected as an example for system identification. The transfer functions of this system is derived by using state-space model structure based on input/output data through experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.1014-1016
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• 1998

A capacitance-type humidity sensor using porous silicon layer is developed. The unique property of this sensor is a structure which has electrodes on the surface of the wafer like a general IC device. To do this. the sensor was fabricated using process such as localized formation of porous silicon, oxidation of porous silicon layer, and etching of oxidized porous silicon layer. The measurement of humidity-sensing ability was done for two type of sensors using porous silicon layer formed in 25 and 35% HF solutions, respectively. As the result, the former sensors showed larger value and variation of capacitance for the relative humidity.

• 한국전기전자재료학회논문지
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• 제23권4호
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• pp.317-322
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• 2010

This paper reports the fabrication and characterization of surface micromachined poly 3C-SiC capacitive pressure sensors on silicon wafer operable in touch mode and normal mode for high temperature applications. FEM(finite elements method) simulation has been performed to verify the analytical mode. The sensing capacitor of the capacitive pressure sensor is composed of the upper metal and the poly 3C-SiC layer. Measurements have been performed in a temperature range from $25^{\circ}C$ to $500^{\circ}C$. Fabrication process of designed poly 3C-SiC touch mode capacitive pressure sensor was optimized and would be applicable to capacitive pressure sensors that are required high precision and sensitivity at high pressure and temperature.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.521-524
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• 2003

This paper is aimed to develop the circuit of a coil-type oil sensor packaged to the automotive engine oil monitoring the deterioration in the driving condition and let a driver notify the optimized time for the exchange of engine oil. By applying the principle which the deterioration of automotive engine oil can be expressed to the dielectric constant, the capacitance bridge circuit and the integrator circuit are designed and packaged to a coil-typed engine oil. In this study. the range of operating temperature of engine oil is experimentally recommended within 55$^{\circ}C$ for the stability of a sensor designed. It is concluded that the characteristics of output voltage converted from the dielectric constant are linearly distributed.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.93-98
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• 1999

Non-contacting capacitive sensors, based on principle of the cross capacitor, for measuring small displacement less than 1.95$\pm$0.5 mm have been fabricated and characterized. To overcome disadvantages of the existed capacitive sensors, the new sensor is consisted of 4-electrodes which are formed 2 active electrodes and 2 guard electrodes on a sapphire plate with diameter 17mm and thickness 0.7 mm, and are symmetrically situated with constant gap of 0.2 mm among the electrodes. The sensor is evaluated to be correlation coefficient of 0.9987 for the range of 1.95$\pm$0.5 mm and that of 0.9995 for 1.95$\pm$0.25 mm range. This sensor can be used for in situ measurements in the mechanical mirror polishing with precision less than $\pm$1${\mu}{\textrm}{m}$.

• 전기학회논문지P
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• 제59권3호
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• pp.317-324
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• 2010

It was used as measuring system to diagnose insulating condition, by which was kept a insulating resistance of inner stack and at the same time was cooled electrochemical heat of reaction of FCEV(fuel cell electric vehicle) stack that used a compressed hydrogen gas reacting with oxygen in accordance with variation on thermal degradation of nonconductive heat transfer fluid. Consequently it was developed a cylindrical multi-terminal capacitive-conductive sensor that could be attached to the internal surface of cooling system pipe to evaluate capacitance and conductivity of heat transfer fluid.