• Korean Chemical Engineering Research
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• 제59권1호
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• pp.35-41
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• 2021

차세대 리튬이차전지용 음극활물질로 각광을 받고 있는 실리콘은 높은 이론용량을 가지고 있어 상용화를 하기 위해 많은 연구가 진행되었다. 하지만 실리콘은 충방전시 부피팽창이 심하고, 전기전도도가 낮은 단점을 가지고 있다. 이러한 문제를 해결하기 위해서 실리콘 표면에 SiO2를 형성시키고, 탄소를 코팅함으로써 실리콘의 부반응을 억제시키고 전기전도도를 향상시켰다. 추가적으로 CNF와 CNT를 복합적으로 첨가하여 부피팽창에 대한 완충효과를 부여하고 전기전도도를 향상시켰다. 제조된 샘플은 XRD, SEM, EDS로 물리적 특성 분석을 실시하였으며, 전기화학적 특성은 전기전도도, EIS, CV 그리고 사이클 테스트를 통해 분석하였다. (Si/SiO2/C)+CNT&CNF 복합체의 경우 다른 샘플들에 비하여 높은 전기전도도 및 낮은 전하전달저항을 보여주었으며, 사이클테스트 결과 첫 번째 사이클에서 1528 mAh/g 그리고 50번째 사이클에서 1055 mAh/g의 용량을 가졌으며 83%의 용량 유지율을 보여주었다.

• 한국정보통신학회논문지
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• 제18권6호
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• pp.1407-1412
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• 2014

근적외선 파장대역 850 nm ~ 1000 nm에서 레이저를 검출하기 위해 포토다이오드의 분광감응도를 향상시키고자 본 논문에서 실리콘 기반 고감도 PIN 포토 다이오드를 제작하고 전기적 및 광학적 특성을 분석하였다. 제작된 소자는 TO-18형으로 패키징 하였고 포토다이오드의 전기적 특성으로 역 바이어스 전압이 5V일 때 암전류는 Anode 1과 Anode 2는 약 0.055 nA 의 값을 나타내었으며 정전용약은 0V 일 때 1 kHz 주파수 대역에서 약 19.5 pF, 200 kHz 주파수 대역에서 약 19.8 pF의 적은 정전용약을 나타내었다. 또한 출력신호의 상승시간은 10 V의 전압일 때 약 30 ns의 고속 응답특성을 확인하였다. 광학적 특성 분석으로는 880 nm에서 최대 0.66 A/W의 분광감응도 값을 나타내었고 1000 nm에서는 0.45 A/W로 비교적 우수한 분광감응도를 나타내었다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 추계학술대회
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• pp.99-102
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• 2004

Display process has adopted RCA clean, being applied to large area and coped with environmental issue for last ten years. However, the approaching concept of ozonized, hydrogenised, or electrolyzed water cleaning technologies is within RCA clean paradigm. In this work, only electrolyzed anode water was applied to clean particles and organics as well as metals based on Pourbaix concept, and as a test vehicle, MgO particles were introduced to prove the new concept. The electrolyzed anode water is very oxidative with high oxidation reduction potential(ORP) and low in pH of more than 900mV and 3.1, respectively. MgO particles were immerged in the anode water and its weight losses due to dissolution were measured with time. Weight losses were in the ranges of 100 to 500 micrograms in 250m1 anode waters depending on their ORP and pH. Therefore it was concluded that the cleaning radicals in the anode water was at least in the range of 1 to 5E20 ea per 250 ml anode water equivalent to IE18 ea/cm3. Hence it can be assumed that the anode water be applied to display cleaning since 1E10 to IE15 ea/cm3 ranges of contaminants are being treated. In addition, it was observed that anode water does not develop micro-roughness on hydrophobic surface while it does on the native silicon oxide.

• Korean Chemical Engineering Research
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• 제62권1호
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• pp.99-104
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• 2024

본 연구에서는 고용량 리튬이온배터리용 음극 소재로 탄소 코팅된 할로우 구조의 실리콘(HSi/C) 복합소재를 제조하였다. CTAB (N-Cetyltrimethylammonium bromide)이 첨가된 Stöber법을 통해 할로우 실리카(HSiO₂)를 합성하였으며, HSiO₂를 마그네슘열 환원한뒤 표면에탄소를 코팅하여 HSi/C 음극복합소재를 제조하였다. 복합소재의물리적 특성과 전기화학적 특성을 CTAB 조성에 따라 조사하였다. FE-SEM 분석 결과 CTAB 조성이 감소할수록 HSiO₂ 입자의 크기가 커졌으나 두께는 감소하였다. 제조된 HSi/C 소재는 다양한 CTAB 비율(0.5, 1.0, 1.5)에서 각각 2188.6, 2164.5, 1866.7 mAh/g의 높은 초기 방전용량을 나타내었으며, 100 사이클의 충·방전 후 0.5-HSi/C가 1171.3 mAh/g의 높은 가역 용량과 70.9%의 용량 유지율을 보여주었다. 전기화학 임피던스 분광법(Electrochemical Impedance Spectroscopy, EIS)으로 저항 특성을 분석하였으며, 0.5-HSi/C 소재가 20 사이클 이후 다른 CTAB 조성의 HSi/C 복합소재에 비해 안정적인 저항 특성을 보이는 것을 확인하였다.

• 자원리싸이클링
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• 제19권4호
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• pp.51-57
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• 2010

실리콘 웨이퍼공정에서 발생하는 실리콘 슬러지로부터 리싸이클링 공정으로 Si-SiC 혼합물을 분리 회수한 다음 기계적 합성법으로 Si-SiC-CuO-C 복합물을 제조하였으며, 리튬전지 음극물질로서의 가능성을 조사하였다. 실리콘 슬러지의 주요 불순물은 절삭유, 금속불순물 및 SiC를 들 수 있다. 오일세정-자력선별-산세척으로 절삭유와 금속불순물을 제거한 다음 고에너지 밀링법으로 Si-SiC-CuO-C 복합물을 합성하였다. 복합물의 충방전 용량과 사이클 특성을 조사한 결과, 수명에 따른 용량 유지 특성이 향상된 우수한 결과를 얻을 수 있었다. 복합물을 구성하는 SiC와 CuO 관련 물질은 실리콘의 부피팽창으로 인한 기계적 파괴 현상을 억제하는 요소로 작용하는 것으로 추정되며, 반면에 Fe 등과 같은 불순물은 전극의 충방전 용량을 감소시키는 요인으로서 전극물질 합성 전에 10 ppm 이내로 제거되어야 하는 것으로 판단된다.

• Journal of Electrochemical Science and Technology
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• 제13권3호
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• pp.339-346
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• 2022

Silicon (Si) has attracted considerable attention due to its high theoretical capacity compared to conventional graphite anode materials. However, Si-based anode materials suffer from rapid capacity loss due to mechanical failure caused by large volume change during cycling. To alleviate this phenomenon, crosslinked polymeric binders with strong interactions are highly desirable to ensure the electrode integrity. In this study, thermally crosslinked polyimide binders were used for Si-alloy anodes in Li-ion batteries. The crosslinked polyimide binder was found to have high adhesion strength, resulting in enhanced electrode integrity during cycling. Therefore, the Si-alloy anodes with crosslinked polyimide binder provide enhanced electrochemical performance, such as Coulombic efficiency, capacity retention, and cycle stability.

• 대한전자공학회논문지TE
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• 제37권2호
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• pp.17-24
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• 2000

In this paper, the stress and transient currents associated with the on and off time of applied voltage were used to measure the density and distribution of high voltage stress induced traps in thin silicon oxide films. The transient currents were due to the discharging of traps generated by high stress voltage in the silicon oxides. The trap distributions were relatively uniform new both cathode and anode interface. The trap densities were dependent on the stress polarity. The stress generated trap distributions were relatively uniform the order of 1011~1021[states/eV/cm2] after a stress voltage. It appear that the stress and transient current that flowed when the stress voltage were applied to the oxide was caused by carriers tunneling through the silicon oxide by the high voltage stress generated traps.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.103-106
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• 1999

In this paper, we suggest the FED packaging technology that have 4mm thickness, using sodalime glass-to-sodalime glass electrostatic bonding. It based on conventional silicon-glass bonding. The silicon film was deposited an around the exhausting hole on FED backside panel. And then, the silicon film of panel was successfully bonded with capping(bare) glass in vacuum environment and the FED panel was vacuum-sealed. In this method, we could achieve more 153 times increased conductance and 200 times increased vacuum efficiency than conventional tube packaging method. The vacuum level in panel, by SRG test, was maintained about low 10$_{-4}$ Torr during above two months And, the light emission was observed to 0.7-inch tubeless packaged FED. Then anode current was 34 $\mu$ A. Emission stability was constantly measured for 10 days.

• 한국재료학회지
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• 제15권1호
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• pp.66-72
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• 2005

Surface modification of the silicon-coated graphite was carried out at $200^{\circ}C\~800^{\circ}C$ under hydrogen atmosphere. The silicon-coated graphites were prepared by fluidized-bed spray coating method. The components of silicon films prepared on the graphite consist of SiO, $SiO_x\;(1. The components of silicon films at $200^{\circ}C$ of heat treatment brought on the higher fraction of SiO and $SiO_x$ than that of $SiO_2$. However, inactive $SiO_2$ fraction increases with increase of the heat treatment temperature. The high content of SiO and $SiO_x$ in the silicon film on graphite leads to the higher discharge capacity in our experimental range.

• 한국결정성장학회지
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• 제10권6호
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• pp.412-417
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• 2000

High electric field stressed trap distributions were investigated in the thin silicon oxide of polycrystalline silicon gate metal oxide semiconductor capacitors. The transient currents associated with the off time of stressed voltage were used to measure the density and distribution of high voltage stress induced traps. The transient currents were due to the discharging of traps generated by high stress voltage in the silicon oxides. The trap distributions were relatively uniform near both cathode and anode interface in polycrystalline silicon gate metal oxide semiconductor devices. The stress generated trap distributions were relatively uniform the order of $10^{11}$~$10^{12}$ [states/eV/$\textrm{cm}^2$] after a stress. The trap densities at the oxide silicon interface after high stress voltages were in the $10^{10}$~$10^{13}$ [states/eV/$\textrm{cm}^2$]. It was appeared that the transient current that flowed when the stress voltages were applied to the oxide was caused by carriers tunneling through the silicon oxide by the high voltage stress generated traps.