• 한국전기전자재료학회논문지
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• 제34권2호
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• pp.126-129
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• 2021

We fabricated plate typed shunt resistors composed of carbon nanotube (CNT) and metal alloy for measuring DC current. CNT plates were prepared from dispersed CNT/Urethane solution by squeezing method. Cu/Ni alloys were prepared from composition-designed alloy wires for adjusting the temperature coefficient of resistance (TCR) by pressing them. As well, we fabricated a hybrid resistor by squeezing the CNT/Urethane solution on the metal alloy plate directly. In order to confirm the composition ratio of the Cu/Ni alloy, we used an energy-dispersed X-ray spectroscopy (EDX). Cross-section and surface morphology were analyzed by using a scanning electron microscopy (SEM). Finally, we measured the initial resistance of 2.35 Ω at 25℃ for the CNT paper resistor, 7.56 mΩ for the alloy resistor, and 7.38 mΩ for the hybrid resistor. The TCR was also measured to be -778.72 ppm/℃ at the temperature range between 25℃ to 125℃ for the CNT paper resistor, 824.06 ppm/℃ for the alloy resistor, and 17.61 ppm/℃ for the hybrid resistor. Some of the hybrid resistors showed a near-zero TCR of 1.38, -2.77, 2.66, and 5.49 ppm/℃, which might be the world best-value ever reported. Consequently, we could expect an error-free measurement of the DC current using this resistor.

• 한국전자파학회논문지
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• 제7권2호
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• pp.157-166
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• 1996

분포 혼합 종단 처리 방식을 채택하고 있는 TEM Cell에 있어서, 내부 도체상의 전류 흐름 및 종단에서의 전류 흐름 해석 방법에 대하여 연구하였다. 회로 해석법을 적용하여 내부 도체 종단부에서의 전류 흐름의 직진성 개선 및 그에 따른 전력 소모를 고려한 최적 종단 저항 네트워크를 설계 하였다. 기존의 각 저항들을 등 간격으로 배치 시켜 구성한 저항 네트워크와 연구결과 제안된 저항 네트워크의 종단 전류 흐름에 대한 수치 해석을 수행하였으며, 두 네트워크를 각각 제작하여 적외선 촬영을 한 결과, 수치 해석 결과와 일치함을 입증하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.628-635
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• 2004

The characteristic of thin film resistor with low TCR( temperature coefficient of resistance ) and high precision are studied. The thin film resistor for 1/4W was fabricated and characteristic of these resistors was investigated. The fabricated device had the thickness of $2.48{\leqq}$ and the resistivity of $0.27{\omega}mm$. The electrical characteristic was evaluated by HP 4339B and 4284A instruments with HP l6339A. The profile of trimmed structure was also measured by non contact interferometer. The change of resistance and TCR increased with increasing roughness and resistance. To reduce the effect of stress annealing treatment was performed in the range of 563 to 623 K after trimming. The characteristic was improved after annealing. It is expected the fabricated device can be useful for high precision and low TCR. Fabricated thin film resistor has average deviation of resistance less than $0.35{\%}$ and TCR within 60.60ppm/K.

• 대한전기학회논문지:전력기술부문A
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• 제53권1호
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• pp.31-37
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• 2004

In this paper, the analysis result of the switching surge in substation including GIS(Gas Insulated Switchgear) has been described using the EMTP(Electro Magnetic Transient Program) program. After performing the modeling of the input data, we have reviewed the energization overvoltages of GCB(Gas Circuit Breaker) without closing resistor in 345kV network, according to the conditions of simultaneously operating switch and statistically operating switch. Firstly, it can be known that the energization overvoltage of single line is higher than that of parallel energized line. Secondly, the maximum energization overvoltage obtained in statistics switch is higher than one in simultaneous switch. From these results, it can be known that the phase-to-earth energization overvoltages of $\alpha$-$\beta$ section are less than 2.2 p.u when closing resistor is eliminated. Therefore, it is possible to consider the circuit breaker eliminated the closing resistor in $\alpha$-$\beta$ section.

• 한국초전도ㆍ저온공학회논문지
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• 제1권2호
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• pp.49-53
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• 1999

We fabricated a resistive superconducting fault current limiter (SFCL) with a shunt resistor in order to bypass the transient current at faults. The SFCL consists of a YBCO films coated with an Au layer (10$\Omega$ at room temperature). which is to disperse the heat generated at hot spots in the YBCO films, and a 5$\Omega$ shunt resistor. The minimum quench current of the SFCL was found to be 12.2Apeak. This SFCL successfully controlled the fault current to below 23 Apeak. Which is otherwise to increase up to 103 Apeak. With the shunt resistor, the temperature of the SFCL rose the temperature of the SFCL rose three times slower than without the shunt, whereby the SFCL is protected at high currents.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.212-213
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• 2006

Polymer thick film resistor paste was fabricated using various materials. Inorganic materials of carbon black and graphite were selected as fillers and epoxy resin was selected as organic material. Solvent with high boiling temperature was applied to adjust viscosity. A designed test coupon pattern was used to evaluate fabricated resistors. Aspect ratio of 1 was selected for evaluating resistor values. Electrical properties of fabricated resistors were measured and their values analyzed in relation to paste composition. PTF fabricated using carbon black as fillers achieved resistor value of $530{\Omega}/sq$.

• 전기학회논문지
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• 제56권4호
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• pp.724-729
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• 2007

In this paper, we propose a new diagnosis method of DC/DC converter aging. The method is based on variations of the parasitic resistor for the aging process. We apply an on-line diagnosis of the DC/DC converter because the observation is not a device, but a system. This study proposes a method of DC/DC converter diagnosis by analyzing the variations of model on the variations of parasitic resistor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.168-170
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• 2001

The NiCr is an important material for present thin-film resistor application owing to its low TCR and thermal stability. In this work, the NiCr thin films were deposited on corning glass substrate by reactive magnetron sputtering and the annealing at temperatures range from 300 to $500^{\circ}C$ for 20 min in vacuum. X-ray, AFM, $R_s$(surface leakage current) have been used to study the structural and electrical properties of the NiCr thin films. The high precision NiCr thin films resistor with TCR(temperature coefficient of resistance) of less then 10 ppm/$^{\circ}C$ was obtained under in in-situ annealing at $300^{\circ}C$ on Cr buffer layer substrate. It is clear that the NiCr thin-films resistor electrical properties are low TCR related with it's annealing and buffer layer condition. NiCr thin film resistor having a good thermal stability and low TCR properties are expected for the application to the dielectric material of passive component.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1476-1478
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• 2002

In recent years, the tantalum nitride(TaN) thin-film has been developed for the electronic resistor, inductor and capacitor. In this papers, this study presents the surface profile and sheet-resistance property relationship of reactive-sputtered TaN thin film resistor processed by TaN(tantalum nitride) on alumina substrate. The TCR properties of the TaN films were discussed in terms of crystallization and thin films surface morphology due to annealing temperature. It is clear that the TaN thin-films resistor electrical properties are low TCR related with it's annealing temperature and ambient annealing condition. Respectively, at $300{\sim}400^{\circ}C$ on vacuum and nitrogen annealed thin film resistor having a goof thermal stability and lower TCR properties then as deposited thin films expected for the application to the dielectric material of passive component.

• 마이크로전자및패키징학회지
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• 제12권1호
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• pp.1-7
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• 2005

저항 값을 맞추기 위한 트리밍 공정이 낮은 저항온도계수와 높은 정밀성을 요구하는 박막저항기 특성에 미치는 영향에 대한 연구가 수행되었다. 스퍼터링 방법으로 제조된 박막 저항기의 트리밍 속도에 따른 저항기의 특성 변화와 온도계수의 변화가 관찰되었다. 트리밍 속도의 증가에 따라서 박막 저항기 특성은 저하되었으며, 열처리로 저항 값의 평균 편차 $0.26\%$ 및 저항온도계수 52.77(ppm/K)의 개선효과가 있었다. 1k$\Omega$와 10k$\Omega$저항기가 100k$\Omega$ 박막저항기 보다는 특성이 양호하였으며, 트리밍 속도의 치적 조건으로는 20mm/sec와 특성 개선을 할 수 있는 최적 열처리 온도는 593K였으며 최적 조건에서 제작된 저항기의 저항 값의 평균 편차는 $0.31\%$ 및 저항온도계수 10(ppm/K)미만이었다.