• 열처리공학회지
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• 제14권3호
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• pp.151-154
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• 2001

$TiO_2$ thin film has wide application because of its high capacitanca, reflection, and good transmissivity in visible range. $TiO_2$ thin film can be made by thermal deposition method, reactive evaporation method, activated reactive evaporation(ARE) method. In the case of thermal deposition, the oxygen deficiency can occur because the melting point of Ti is very high. While in the case of reactive evaporation, high density $TiO_2$ can not be made, because reactive gas($O_2$) and evaporated material(Ti) are not fully combined, activated reactive evaporation, $TiO_2$ is easily deposited at lower gas pressure compared with reactive evaporation because the ionized reactive gas is made by plasma. Therefore, activated reactive evaporation is very useful to deposit the material having the high melting point. In this work, we formed $TiO_2$ thin film by activated reactive evaporation method. The surface of $TiO_2$ thin film was analyzed by X-ray photoelectron spectroscopy. The surface morphology which was analyzed by atomic force microscopy(AFM) shows that feature of the film surface is uniform. The dielectric capacitance, withstanding voltage were $600{\mu}F/cm^2$, 0.4V respectively. In further work, we can increase the withstanding voltage by improving the deposition parameter of substrates.

• 열처리공학회지
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• 제14권5호
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• pp.292-296
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• 2001

In this work, an ultra-high vacuum activated reactive evaporation equipment was built. With reaction of Al and oxygen plasma, $Al_2O_3$ was deposited on the surface of etched Al foil. The chamber was evacuated down to $2{\times}10^{-7}$ torr initially. The Ar and $O_2$ gas introduced into the chamber to maintain $5{\times}10^{-5}$ torr during deposition. Ar gas prevents recombining of the ionized oxygen. Evaporation was maintained by electron beam evaporator continuously. Heating filament and electrode were used in order to generate plasma. The substrate bias of -300V was introduced to accelerate deposition of evaporated Al atoms. The composition and morphology of deposited $Al_2O_3$ films were analyzed by x-ray photoelectron spectroscopy(XPS) and atomic force microscopy (AFM), respectively. The Al oxide was formed on the surface of etched Al foil. According to AFM results, the surface morphology of $Al_2O_3$ film indicates uniform feature. Dielectric characteristic was measured as a function of frequency. Measured withstanding voltage and capacitance were 52V and $24{\mu}F/cm^2$, respectively. The obtained $Al_2O_3$ film shows clean condition without contaminants, which could be adapted to capacitor production.

• 한국재료학회지
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• 제4권3호
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• pp.280-286
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• 1994

As-grown $YBa_2Cu_3O_{7-x}$ films on MgO(100)substrates were prepated by a reactive co-evaporation method, and effects of activated oxygen plasma on the crystallinity and superconductivity at substrate temperature ranging from $450^{\circ}C$ to $590^{\circ}C$ were investigated. The film deposited under the activated oxygen plasma at the substrate temperature of $590^{\circ}C$ had a single crystal phase. Whereas, when films were deposited under only oxygen gas, they were not in perfect single crystal phase but with slight polycrystalline nature. When the substrate temperature was $590^{\circ}C$, $Tc_{zero}$'s were 83K and 80K for films with and without activated oxygen plasma, respectively. The critical temperature, the crystal structure and the surface morphology of as-grown films were found to be insensitive to the activated oxygen plasma which is introduced during deposition instead of oxygen gas, but the crystalline quality was improved somewhat by the introduction by the introduction of actvated oxygen plasma.

• E2M - 전기 전자와 첨단 소재
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• 제5권4호
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• pp.400-405
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• 1992

활성화 반응성 증착법으로 비저항 1.7*$10^{-3}$-8.0*$10^{-3}$ohm.cm, 전하운반자 농도 3.4*$10^{19}$-2.8*$10^{20}$$cm^{-3}$, 이동도 12-23$cm^{2}$/V.s, 금지대역 폭 3.35eV인 In/sib 2/ $O_{3}$박막을 KBr과 실리카 기판에 성장시켰다. 광투과율은 가시광선 영역에서 80% 이상을 나타냈으며 적외선 영역에서도 양호한 특성을 나타냈다. 박막성장시는 비정질 상태였으나 150.deg.C 이상에서 열처리했을 때 결정화현상이 관찰되었다.

• 한국표면공학회지
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• 제32권3호
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• pp.467-471
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• 1999

BN films were grown on silicon (l00) substrate by magnetically enhanced activated reactive evaporation (ME-ARE) with pulsed DC power instead of r.f. for substrate biasing. The deposited films were analyzed using Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). FTIR results show that the intensity of absorption band of $sp^2$ bond of BN decreased and that of $sp^3$ bond of c-BN increased with increasing pulsed DC bias voltage applied to substrate. The initially grown layer at the interface was observed by TEM and considered to be of$ sp^2$-bonded BN. The cross-sectional and planar TEM micrographs show that the upper layer on the initial layer was the single phase c-BN. It is concluded that cubic boron nitride films could be synthesized by ME-ARE process with pulsed DC biasing.

• 한국해양학회지:바다
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• 제27권3호
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• pp.144-157
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• 2022

비활성기체는 화학적, 생물학적 반응을 하지 않는 보존적인 특성을 가지고 있어 해양에서 수온과 염분 변화, 기체 주입, 해수의 혼합과 빙하 융해수의 분포와 같은 물리적인 변화의 추적자로 활용되고 있다. Ne, Ar과 Kr을 정밀하게 분석하기 위해 사중극자 질량 분석기, 고진공 전처리 라인, 초저온 냉각 트랩과 동위원소 표준기체로 구성된 분석 시스템을 제작했다. 고진공 라인은 시료의 용존 기체를 추출하여 동위원소 표준기체와 혼합하는 시료추출부, 합금 물질을 이용하여 반응성 기체를 제거하고 초저온 냉각 트랩으로 비활성기체를 기화점에 따라 분별 증류하는 기체 준비부, 비활성기체를 원소별로 측정하는 기체 측정부로 구성하였다. 기체준비부에 결합한 초저온 냉각 트랩은 질량분석기 내 Ar와 CO₂의 부분압을 현저히 낮추어 Ne 동위원소 분석의 오차를 감소시켰다. 동위원소 표준기체는 ²²Ne, ³⁶Ar과 ⁸⁶Kr를 혼합하여 제작하였고, 혼합 표준 기체의 원소별 양은 대기를 반복 측정하여 역동위원소 희석법으로 결정했다. 대기 평형수 반복 분석의 상대 오차는 Ne, Ar과 Kr에 대해 각각 0.7%, 0.7%, 0.4%이었다. 반복 측정한 대기 평형수의 농도와 포화 농도의 차이로 확인한 분석시스템의 정확도는 Ne, Ar, Kr에 대해 각각 0.5%, 1.0%, 1.7%이었다.