한국전기전자재료학회 뉴스

한국전기전자재료학회 한국전기전자재료학회 2022 전기전자재료 Vol.35 No.4

자기전기복합체의 비공진 및 공진 상태에서의 자기전기 결합 특성 평가 방법

파틸디팍,류정호 한국전기전자재료학회 2022 전기전자재료학회논문지 Vol.35 No.4

자기전기복합체(magnetoelectric, ME compositie)는 자왜재료와 압전재료의 결합현상을 이용하는 재료로서지난 20여 년간 이론적, 실험적으로 많은 연구가 진행되어 왔다. 자기전기복합체의 출력특성은 구성하는 소재, 계면층,복합체의 형상, 자기장하 진동모드 등의 많은 구성요소의 최적화를 통하여 급속히 향상되고 있다. 하지만 자기전기복합체의 자기전기 결합 특성 평가는 대부분의 연구들에서 구체적인 방법을 제시하지 않아 어떻게 측정한 것인지가 불명확한 경우가 많다. 본 논문에서는 자기전기복합체의 비공진, 공진상황에서 자기전기 전압계수를 어떻게 측정할 수 있는지에 대한 자세한 방법을 소개한다. 평가를 위한 샘플로서 대칭적인 구조를 가지는 Gelfenol/PMN-PZT/Gelfenol자기전기복합체를 제조하였다. 압전 재료로는 이방성의 (011) 32 모드의 PMN-PZT 압전 단결정과 자왜재료로는 Galfenol 합금을 사용하여 에폭시로 접착하였다. 컴퓨터 인터페이스로 자동화된 자기전기 전압특성 측정 시스템의 구성을 우선 설명하고, 자기전기 결합특성의 측정 방법을 단계별로 설명한다. 본 튜토리얼 논문에서는 자기전기결합 특성과 특성평가방법을 이해하고자 하는 연구자들에게 도움이 될 수 있는 평가방법의 원리와 절차를 제공하고자 하였다.

게이트 바이어스에 의한 a-IGZO 박막 트랜지스터 전기적 특성의 열화현상 분석

김태수,전재홍 한국전기전자재료학회 2021 전기전자재료학회논문지 Vol.34 No.3

The transfer characteristics of amorphous indium gallium zinc oxide thin film transistor (a-IGZO TFT) showed the distortion in the subthreshold region after gate bias stress, in addition to the parallel shift of threshold voltage. The capacitancevoltage (C-V) curve was also deformed from its initial shape after the gate bias stress. This study analyzes both the C-V and transfer curves plotted on the same gate voltage axis in order to investigate the mechanism driving the distortion in the transfer curve. It is deduced that an additional interfacial trap states at the bottom interface of a-IGZO are produced during gate bias stress, thereby they exhibit the back channel effect, which explains the origin of the distortion in the transfer curve and the deformation of C-V curve.

저온소성 TiO2 페이스트를 이용한 염료감응 태양전지의 특성 연구

정유라,김은미,구할본 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.5

본 연구에서는 TiO2 입자간의 우수한 네트워크와 TiO2 박막과 FTO 기판과의 접착특성을 향상시키기 위하여 TiO2 페이스트 제작시 TTIP를 첨가하여 저온 소성용 TiO2 페이스트를 제조 및 광전극에 이용함으로써 염료감응 태양전지의 전기화학적 특성을 향상시켰다. TiO2 페이스트에 TTIP를 첨가하여 TiO2 입자간의 네트워크와 기판과의 접착특성을 향상시켜 빛에 의해 여기된 전자가 염료의 기저상태 또는 전해질의 산화/환원 준위로의 재결합을 방지하여 전자가 투명 전도성 FTO 기판까지의 이동이 용이하여 전류밀도 및 광전변환효율 특성을 향상시켰다. TTIP를 이용한 염료감응 태양전지의 전자전달시간은 4.3×10-3 s로 빠르고 전자재결합시간을 3.0×10-2 s로 느려 free-binder 샘플에 비해 높은 전류밀도 및 광전변환효율을 나타내었다. TTIP를 첨가한 염료감응 태양전지의 Voc, Jsc, FF 및 η은 각각 0.72 V, 7.66 mA cm-2, 64.11% 및 3.54%로 FP2의 광전변환효율의 약 1.3배 향상되었다. In this paper, we have developed a low temperature process to make two type of paste by using TiO2 nanoparticles(P25). The interconnections between substrate and TiO2 films or link between particles of free-binder paste(FP1, FP2, FP3) is very poor. Therefore, the Titanium(Ⅳ) isopropoxide was added to the TP paste to improve the interconnection. Electron transport time (τt) and recombination time (τr) are analyzed by IMPS (intensity-modulated photocurrent spectroscopy) and IMVS(Intensity-modulated photovoltage spectroscopy). In the results, τt of TP paste based DSSCs (about 4.3×10-3) is faster than other samples. τr is longer from 2.7×10-2 s of FP2 to 3.0×10-2 s of TP. A solar conversion efficiency (DSSCs) of TP is 3.54% for an incident solar energy of 100 mW cm-2 (meanwhile, 2.70% for DSSCs with FP2). The conversion efficiency is increased by 1.3 times.

실리콘 웨이퍼 위에 제작된 DLPC 지질막의 전기적특성

이우선,김충원,이강현,정용호,김남오,김상용 한국전기전자재료학회 1998 전기전자재료학회논문지 Vol.11 No.12

MLS capacitor with lipid ultra thin films were deposited by Langmuir-Blodgett (LB) method on the silicon wafer. The current versus voltage and capacitance versus voltage relationships are depend on the applied voltage, electrode area and electrode materials. LB films deposited were made of L-$\alhpa$-DLPC, the 1 layer’s thickness of 35${\AA}$ was measured by ellipsometer. And MLS capacitor with different electrode materials, the work function of these materials was investigated to increase the leakage current. The result indicated the lower leakage current and very high saturation value of capacitance was reached within 700-800 pF when the two electrode was Ag. And $\varepsilon$1, $\varepsilon$2 versus photon energy showed good film formation.

전계가 가해진 절연유의 유동대전 특성 고찰

허창수,정중일 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.4

Streaming electrification on insulating paper and pressboard under D.C. and A.C. electric field was investigated by using paper tubes and oil circulation apparatus. At first, flowing of static charges as measured with no electric field. As the temperature of oil increased, the measured current curve hows peak. As the velocity increased, it shows increasing exponential curve. Then, we applied A.C. and D.C. electric field on paper tube and the current from relaxation tank to earth was measured, which other factors such as temperature and velocity were varied like case of no electric field. The ions in oil carry the charges. So electric field makes asymmetry effect, and electrophoretic effect on ions in oil. We find that as the electric field intensity increased, the charges which were made by electric double layer were increased. The charge vs. velocity curve made peak point at a velocity.

$e^-$-$CF_4$산란중에서 전자군의 확산계수 및 에너지분포함수 연구

하성철,임상원 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.4

In this paper, the behavior of electron swarm parameters and energy distribution function of the discharge under high E/N condition in e$^{-10}$ -CF$_{4}$ gas have been analysed over the E/N range from 1-300(Td) by the MCS and BEq methods using set of electron collision cross section determined by the authors. The swarm parameters and energy distribution function have been calculated for the pulsed Townsend, steady-state Townsend and Time of Flight methods. The results gained that the value of electron swarm parameters such as the electron drift velocity, the electron ionization and attachment coefficients and longitudinal diffusion coefficients in agreement with the experimental and theoretical data for a range of E/N. The electron energy distribution function has been explained and analysed in e$^{-10}$ -CF$_{4}$ at E/N : 5, 10, 100, 200, 300(Td) for a case of the equilibrium region in the mean electron energy and respective set of electron collision cross sections. The validity of the results has been confirmed by TOF and SST methods.

비냉각형 적외선 센서로 응용하기 위한 반도성 YBa₂Cu₃O_6+x 박막의 열처리 온도에 따른 구조적 전기적 특성

이태호,이성갑,여진호,정혜린,Lee, Tae-Ho,Lee, Sung-Gap,Yeo, Jin-Ho,Jung, Hye-Rin 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.10

YBCO thin films on $SiO_2$/Si substrate were fabricated by spin-coaing of an alkoxide-derived precursor and heat treatment. The structural and electrical properties of the YBCO films were investigated as functions of annealing temperature at $600{\sim}800^{\circ}C$. Although YBCO single phase was not synthesized, dense films of YBCO matrix phase and minor second phases have been successfully fabricated at the annealing temperatures of $650{\sim}800^{\circ}C$. Thickness and temperature coefficient of resistance (TCR) of YBCO thin films with annealing temperature of $750^{\circ}C$ were 0.31 ${\mu}m$ and $-2.92%/^{\circ}C$, respectively.

배전 케이블의 절연체내 불순물이 전기전도도에 미치는 영향

이우선,김남오,정용호,최재곤,김형곤,김상준 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.5

Effects of metal impurities in insulation of distribution cables on electrical conduction of distribution cables was investigated. Samples of Al, Cu, Fe are fabricated as metallic impurities, and measured electrical conductivity in the voltage range of 0~10 KV. Temperature dependent effect of hysteresis curves and the relationship between forward and reverse current due to impurity content are discussed.

제작방법에 따른 전력케이블용 폴리에틸렌 박막의 전기전도특성

조경순,이용우,이수원,홍진웅 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.5

In order to investigate the electrical conduction properties of polyethylene thin film for power cable with manufacturing methods, the thickness of specimen was the 30, 100[${\mu}{\textrm}{m}$] of LDPE and 200[${\mu}{\textrm}{m}$] of XLPE were manufactured. The experimental condition for conduction properties was measured until the breakdown occurs at temperature ranges from 30 to 110[$^{\circ}C$] and the electric field from 1$\times$10$^3$to 5$\times$10$^{6}$ [V/cm]. As for increase of temperature, the current density of LDPE was increased with constant ratio in low field, but changes with exponential function in high electric field. The tunnel current of pre-breakdown region is shifted toward low field as much as thermal excitation energy. At low electric field, the XLPE showed dominant electrical conduction properties by thermal excitation, and transformation of the electron was resisted by the crystal at high electric field.