동시 소성된 저항/저온 동시 소성 세라믹(LTCC) 이중층의 캠버에 영향을 미치는 인자

홍옥연,민석홍 한국재료학회 2023 한국재료학회지 Vol.33 No.12

The sintering shrinkage behaviors of low temperature cofired ceramics (LTCC) and resistors were compared using commercial LTCC and thick-film resistor pastes, and factors influencing the camber of cofired resistor/LTCC bi-layers were also investigated. The onset of sintering shrinkage of the resistor occurred earlier than that of LTCC in all resistors, but the end of sintering shrinkage of the resistor occurred earlier or later than that of LTCC depending on the composition of the resistor. The sintering shrinkage end temperature and the sintering shrinkage temperature interval of the resistor increased as the RuO2/glass volume ratio of the resistor increased. The camber of cofired resistor/LTCC bi-layers was obtained using three different methods, all of which showed nearly identical trends. The camber of cofired resistor/LTCC bi-layers was not affected by either the difference in linear shrinkage strain after sintering between LTCC and resistors or the similarity of sintering shrinkage temperature ranges of LTCC and resistors. However, it was strongly affected by the RuO2/glass volume ratio of the resistor. The content of Ag and Pd had no effect on the sintering shrinkage end temperature or sintering shrinkage temperature interval of the resistor, or on the camber of cofired resistor/LTCC bi-layers.

병렬로 접속된 저항체에서 저항온도계수의 거동

이선우,Lee, Sunwoo 한국전기전자재료학회 2018 전기전자재료학회논문지 Vol.31 No.2

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.

Phase Current Sensing Method Using Three Shunt Resistors to Eliminate Immeasurable Area in Voltage Vector Plane

Duck-Yong Yoon,Dong-Ki Kim,Do-Hyun Jang 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.1

This paper proposes a current sensing method to eliminate the immeasurable areas in three-phase inverters using the shunt resistors. Conventional shunt resistor-based current sensing methods have immeasurable areas in the voltage vector plane. Since motor control performance is degraded by the immeasurable area, various current reconstruction techniques have been proposed to expand the measurement range. Nevertheless, the software algorithm is quite complex, and the reconstruction ability is still unsatisfactory. In the proposed method, shunt resistors are located in series with the inverter output lines to obtain the motor phase currents. Both ends of the shunt resistors are at the high-potential as the dc-link voltage. High-potential voltages are lowered to the common-mode voltage level of the analog amplifi er using voltage divider, and voltage drops across shunt resistors are detected by instrumentation amplifi ers. Immeasurable areas are completely eliminated because phase currents can be detected directly through line shunt resistors. Simulations and experiments are carried out to verify the eff ectiveness of the proposed current sensing method

피드백 네트워크를 사용한 Pseudo 저항을 갖는 LDO 레귤레이터

정준모,Jung, Jun-Mo 한국전기전자학회 2016 전기전자학회논문지 Vol.20 No.1

본 논문에서는 기존 LDO regulator에서 많이 사용 되는 피드백 저항을 Pseudo resistor를 이용하여 동작하기 위한 LDO regulator를 제안한다. 제안 된 Pesudo resistor를 사용한 Feedback network는 기존 피드백 저항보다 면적이 작으면서도 기존 LDO regulator의 역할을 하며, 노이즈를 갖는 LDO regulator의 단점을 보완하고자 제안되었다. 기존 LDO regulator와 비교하여 비슷한 성능을 가짐에도 불구하고, Overshoot를 감소시키고 면적을 줄여 더 높은 효율을 제공할 수 있다. 설계한 회로는 동부 하이텍의 0.18um CMOS 공정을 이용하였다. In this paper, we propose LDO regulator to operate using Pseude resistor instead of widely used Feedback resistor in conventional LDO regulator. Proposed Feedback network using Pseudo resistor has smaller area than the conventional feedback resistor and plays the role of an conventional LDO regulator. Thus, it has been proposed to compensate for the disadvantages of LDO regulator with noise. Although proposed LDO regulator compared with conventional LDO regulator has similar performance, this LDO regulator provide higher efficiency by reducing the overshoot and decreasing the area. This circuit was designed to using a Dongbu Hitek 0.18um CMOS process.

Solving for the Best Value of Bias Resistor to Promote Stability of Rs485 Fieldbus

Liang Zhao,Ruobing Liang,Jili Zhang 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.3

This paper analyzes several factors affecting the reliability of RS485 fieldbus communication, and then establishes the equivalent circuit model in order to solve bias resistor. The value range of bias resistor on the fieldbus is 556Ω~716Ω, which is determined by using the law of KCL and current limiting method. Furthermore the best value of bias resistor is derived about 670Ω for different unit loads based on the relationship between number of network nodes and the value of bias resistor, and the corresponding maximum network nodes of fieldbus are determined too. The research of this paper provides theoretical basis and engineering design guidance for the application of RS485 fieldbus.

Embedded Resistor 적용을 위한 Organic 기판 위에 균일한 두께의 형상을 갖는 저항체의 제조공정과 편차에 대한 조사

박화선(Hwasun Park) 대한전자공학회 2008 電子工學會論文誌-SD (Semiconductor and devices) Vol.45 No.4

본 논문에서는 Embedded resistor 적용을 위한 오개닉 기판 위에 캐버티(Cavity) 공정에 의해서 형성된 균일한 두께를 갖는 저항체의 제조 방법과 저항편차에 대해서 조사했다. 기존의 스크린 프린팅에 의해서 발생하는 PCB의 위치에 따른 저항값의 편차를 개선하기 위하여 캐버티 공정을 소개했다. 원하는 모양과 부피를 갖는 저항은 스크린 프린팅과 페이스트를 이용하여 cavity 공정에 의해 정확하게 형성되어 졌다. 이 방법은 PCB의 생산 공정시간을 줄일 수 있고, 스크린 프린팅의 정밀도에 의한 큰 영향 없이 빠르게 공정 조건을 배치할 수 있으므로써 생산량을 개선시킬 수 있다. This paper investgated on fabrication process and tolerance of resistance body with a uniform thickness formed by the process of cavity type on organic substrate for application of embedded resistor. To improve the tolerance of resistance value according to a position of PCB cause by conventioanl screen printing, we introduced the process of cavity type from organic substrate. A resistor with a desired shape and volume was precisely formed by the process of cavity using a resistor paste and screen printing. This method can increase PCB's productivity by shortening its prodcution time because process conditions of a screen prining device can be set quickly without any affection on its position accuracy.

인쇄 및 소결조건이 AlN 기판용 후막저항체의 특성에 미치는 영향

구본급,Koo, Bon Keup 한국세라믹학회 2014 한국세라믹학회지 Vol.51 No.4

$RuO_2$-based high frequency thick-film resistor paste was printed at the speed of 10, 100, 300 mm/sec on the AlN substrate, and then sintered at between 750 and $900^{\circ}C$. The sintered thick films were characterized in terms of printing and sintering conditions. With increasing printing speed, the thickness and roughness of sintered film increased. The resistance of the thick film resistor was reduced by increasing the printing speed from 10 to 100 mm/sec, but did not significantly change at 300 mm/sec speed. With increasing sintering temperature, the surface roughness and thickness of sintered resistor film decreased. The reduction rate was large in case of fast printed resistor. The resistance of the resistor increased up to $800^{\circ}C$ with sintering temperature, but again decreased at the higher sintering temperature.

NAC Measurement Technique on High Parallelism Probe Card with Protection Resistors

Gyu-Yeol Kim,Wansoo Nah 대한전자공학회 2016 Journal of semiconductor technology and science Vol.16 No.5

In this paper, a novel time-domain measurement technique on a high parallelism probe card with protection resistors installed is proposed. The measured signal amplitude decreases when the measurement is performed by Needle Auto Calibration (NAC) probing on a high parallelism probe card with installed resistors. Therefore, the original signals must be carefully reconstructed, and the compensation coefficient, which is related to the number of channel branches and the value of protection resistors, must be introduced. The accuracy of the reconstructed signals is analyzed based on the varying number of channel branches and various protection resistances. The results demonstrate that the proposed technique is appropriate for evaluating the overall signal performance of probe cards with Automatic Test Equipment (ATE), which enhances the efficiency of probe card performance test dramatically.

Fabrication and Characterization of Ni-Cr Alloy Thin Films for Application to Precision Thin Film Resistors

Lee, Boong-Joo,Shin, Paik-Kyun The Korean Institute of Electrical Engineers 2007 Journal of Electrical Engineering & Technology Vol.2 No.4

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.

Fabrication and Characterization of Ni-Cr Alloy Thin Films for Application to Precision Thin Film Resistors

Boong-Joo Lee,Paik-Kyun Shin 대한전기학회 2007 Journal of Electrical Engineering & Technology Vol.2 No.4

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℃ 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.