• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.2
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• pp.98-101
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• 2018

In this paper, we discuss the fabrication of metal alloy resistors. We connected them in parallel to estimate their resistance and temperature coefficient of resistance (TCR). The fabricated resistors have different resistances, 5 and $10{\Omega}$ and different TCRs, 50 and $200ppm/^{\circ}C$. Each resistor was confirmed to have the correct atomic composition through the use of energy dispersive X-ray (EDX). The resistors' electrical properties were confirmed by measuring resistance and TCR. The resistance and TCR of the resistors connected in parallel were estimated through the increase in resistance due to the increase in temperature, and were compared with the measured values. We are confident that this TCR estimation technique, which uses the increase in resistance due to temperature, will be very useful in designing and fabricating resistors with low and stable TCR.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.725-728
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• 2001

We have fabricated thin films using the DC/RF magnetron sputtering of 74wt%Ni-l8wt%Cr-4wt%Al-4wt%Cu alloy target and studied the effect of the process parameters on the electrical properties for low TCR(Temperature Coefficient of Resistance) films. In sputtering process, pressure, power and substrate temperature, are varied as controllable parameter. The films are annealed to 400$^{\circ}C$ in air and nitrogen atmosphere. The sheet resistance, TCR of the films increases with increasing annealing temperature. It abruptly increased as annealing temperature increased over 300$^{\circ}C$ in air atmosphere. From XRD, it is found that these results are due to the existence of NiO on film surface formed by annealing. As a results of them, TCR can be controlled by variation of sputter process parameter and annealing of thin film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.558-561
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• 2001

Vanadium oxide ($VO_x$) thin films are very good candidate material for uncooled infrared (IR) detectors due to their high temperature coefficient of resistance (TCR) at room temperature. But, the deposition of $VO_x$ thin films showing good electrical properties is very difficult in micro bolometer fabrication process using sacrificial layer removal because of its low process temperature and thickness of thin films less than $1000{\AA}$. This paper presents a new fabrication process of $VO_x$ thin films having high TCR and low resistance. Through sandwich structure of $VO_{x}(100{\AA})/V(80{\AA})/VO_{x}(500{\AA})$ by sputter method and post-annealing at oxygen ambient, we have achieved high TCR more than $-2%/^{\circ}C$ and low resistance less than $10K\Omega$ at room temperature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.558-561
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• 2001

Vanadium oxide ($VO_{x}$) thin films are very good candidate material for uncooked infrared (IR) detectors due to their high temperature coefficient of resistance (TCR) at room temperature. But, the deposition of $VO_{x}$ thin films showing good electrical properties is very difficult in micro bolometer fabrication process using sacrificial layer removal because of its low process temperature and thickness of thin films less than 1000${\AA}$. This paper presents a new fabrication process of $VO_{x}$ thin films having high TCR and low resistance. Through sandwich structure of $VO_{x}$(100${\AA}$)/V(80${\AA}$)/$VO_{x}$(500${\AA}$) by sputter method and post-annealing at oxygen ambient, we have achieved high TCR more than -2%/$^{\circ}C$ and low resistance less than $10K\Omega$ at room temperature.

• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.525-531
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• 2007

Ni(75 wt.%)-Cr(20 wt.%)-Al(3 wt.%)-Mn(4 wt.%)-Si(1 wt.%) alloy thin films were prepared using the DC magnetron sputtering process by varying the sputtering conditions such as power, pressure, substrate temperature, and post-deposition annealing temperature in order to fabricate a precision thin film resistor. For all the thin film resistors, sheet resistance, temperature coefficient of resistance (TCR), and crystallinity were analyzed and the effects of sputtering conditions on their properties were also investigated. The oxygen content and TCR of Ni-Cr-Al-Mn-Si resistors were decreased by increasing the sputtering pressure. Their sheet resistance, TCR, and crystallinity were enhanced by elevating the substrate temperature. In addition, the annealing of the resistor thin films in air at a temperature higher than $300^{\circ}C$ lead to a remarkable rise in their sheet resistance and TCR. This may be attributed to the improved formation of NiO layer on the surface of the resistor thin film at an elevated temperature.

• Proceedings of the IEEK Conference
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• 2004.08c
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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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.352-356
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• 2007

The Ni/Cr/Al/Cu (51/41/4/4 wt%) thin films were deposited by using DC magnetron sputtering method for the application of the resistors having low TCR (temperature coefficients of resistance) and high resistivity from the former printed-results[3]. The TCR values measured on the as-deposited thin film resistors were less than ${\pm}10\;ppm/^{\circ}C$ and $-6{\sim}+1\;ppm/^{\circ}C$ after annealing and packaging process. The TCR values were $-3{\sim}1\;ppm/^{\circ}C$ (ratio of variation : about 0.02 %) and $-30{\sim}20\;ppm/^{\circ}C$ (ratio of variation : about $0.5{\sim}1\;%$) for the thermal cycling and PCT (pressure cooker test), respectively. It was confirmed that the reliability properties of the thin film resistor were good for electronic components.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.3
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• pp.323-327
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• 2024

The low-temperature coefficient of resistance (TCR) is a crucial factor in the development of space-grade resistors for temperature stability. Consequently, extensive research is underway to achieve zero TCR. In this study, resistors were deposited by co-sputtering nickel-chromium-based composite compositions, metals showing positive TCR, with SiO₂, introducing negative TCR components. It was observed that achieving zero TCR is feasible by adjusting the proportion of negative TCR components in the deposited thin film resistors within certain compositions. Additionally, the correlation between TCR and deposition conditions, such as sputtering power, Ar pressure, and surface roughness, was investigated. We anticipate that these findings will contribute to the study of resistors with very low TCR, thereby enhancing the reliability of space-level resistors operating under high temperatures.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.219-222
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• 2019

In this study, we fabricated plate-type shunt resistors with thermal stability by parallelly connecting metal alloy plates with positive temperature coefficient of resistance (TCR) and carbon nanotube (CNT) plates with negative TCR. The metal alloy plates, which were prepared by alloying Cu and Mn with a composition of 91 wt% of Cu and 9 wt% of Mn, showed around $800ppm/^{\circ}C$ of TCR, and the CNT plates prepared from the CNT solution by using the vacuum filtration method showed around $-800ppm/^{\circ}C$ of TCR. The shunt resistor that was fabricated by stacking metal alloy plates and CNT plates in this work showed about $46.93ppm/^{\circ}C$ of TCR. Therefore, we conclude that a shunt resistor with low TCR can be realized by simply adjusting the TCR of the metal alloy only, because the TCR of the CNT plate has an identical value.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.152-155
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• 1996

Platinum thin films were deposited on $Al_2$O$_3$substrate by DC magnetron sputtering for RTD(Resistance Thermometer Devices) temperature sensors. We made Pt resistance pattern on $Al_2$O$_3$substrate by lift-off method and fabricated Pt-RTD temperature sensors by using W-wire, silver epoxy and SOG(spin-on-glass). In the temperature range of 25~40$0^{\circ}C$, we investigated TCR(temperature coefficient of resistance) and resistance ratio of Pt-RTD temperature sensors. TCR values were increased with increasing the annealing temperature, time and the thickness of Pt thin films. Resistance values were varied lineally within the range of measurement temperature. At annealing temperature of 100$0^{\circ}C$, annealing time of 240min and thin film thickness of 1${\mu}{\textrm}{m}$, we obtained Pt-RDT TCR value of 3825ppm/$^{\circ}C$ closed to the Pt bulk value.