• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.184.1-184.1
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• 2013

It is generally known that electron beam has sterilization effects and can activate plant germination and growth. Compared to electron beam, electrical pulse has not been frequently studied with respect to the biological application. In this study, we have analyzed the effects of high voltage pulse on seed germination and growth using various plant species. We have used the high voltage generator for examining seed's responses to the high voltage pulse. The operating voltage and currents of the generator are about 300 kV and 30 kA, respectively. Pulse width is 60 ns. High voltage pulse has slightly activated germination and growth of radish during early stage. Various levels of germination and growth are observed in different plant species after treated with high voltage pulse.

• Applied Science and Convergence Technology
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• 제26권6호
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• pp.214-217
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• 2017

AlSb is a promising material for optical devices, particularly for high-frequency and nonlinear-optical applications. We report the effect of growth temperature on structural properties of AlSb grown on GaAs substrate. In particular we studied the surface of AlSb with the growth temperature by atomic force microscopy, and concluded that optimized growth temperature of AlSb is $530^{\circ}C$. We also show the result of real-time monitoring of AlSb growth by in situ ellipsometry. The results of the structural study are good agreement with the previous reported ellipsometric data.

• 한국결정학회지
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• 제3권2호
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• pp.72-84
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• 1992

EBFZM( Electron Beam Floating Zone Melting ) 법을 이용하여 니오븀에서의 침입형불순물 정련기구, 단결정 성장기구 및 유동현상을 연구하였다. EBFZM 은 산소와 질소의 제거에 효과적이었고,탄소의 경우 유확산펌프에서의 Backstream으로 인하여 약간 증가하는 경향성을 보였다. 원소재에 집합조직이 존재 하는 경우, EBFZM을 시행한 후의 결정성장 방위가 원소재의 집합조직과 일치하였으며,이로부터 2차 재결정에 의한 단결정 성장기구를 제안하였다. 또한,용 응대의 유동현상을 연구하여 낮은 Prandtl수인 니오븀에서도 Marangoni대류가 존재하여 결정내부의 striation을 유발시키고 산소와 질소에 대한 정련효과를 증대시킴을 밝혔다.

• 한국재료학회지
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• 제13권8호
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• pp.485-490
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• 2003

We have developed a new way of the constant growth technique to maintain a grating height of originally-etched V-groove of submicron gratings up to 1.5 $\mu\textrm{m}$ thickness by a low pressure metalorganic chemical vapor deposition. The constant growth technique is well performed on two kinds of submicron gratings that made by holography and electron (e)-beam lithography GaAs buffer layer grown on thermally deformed submicron gratings has an important role in recovering the deformed grating profile from sinusoidal to V-shaped by reducing mass transport effects. The thermal deformation effect on submicron gratings made by e-beam lithography is less than that on submicron gratings made by holography. The constant growth technique is an important step to realize complex optoelectronic devices such as one-step grown distributed feedback lasers and two-dimensional photonic crystals.

• 한국진공학회지
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• 제12권4호
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• pp.251-256
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• 2003

분자선에피탁시법을 이용하여 InP(001) 기판위에 성장한 InAlAs 에피층의 특성에 대한 성장온도 (370-$430 ^{\circ}C$)의 효과를 Normalski 현미경, 원자력현미경 (AFM), 광발광 (PL), 이중결정 x-선 회절법 (DCXRD)을 사용하여 분석하였다. InAlAs 에피층의 표면형상, 구조적, 광학적 특성은 370-$400^{\circ}C$에서 성장한 시료에서는 성장온도의 증가로 향상되지만, $430 ^{\circ}C$로 성장한 시료에서는 특성이 나빠졌다. 결과적으로 $400 ^{\circ}C$로 성장한 InAlAs 에피층의 특성이 가장 우수하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.484-488
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• 1997

BSCCO thin film is fabricated cia both processes of co-deposition and layer-by-layer deposition at an ultralow growth rate using ion beam sputtering method. The adsorption of Bi atom and the appearance of Bi-2212 phase shows large differance between both processes. It is found that the resident time of Bi vapor species on the surface of the substrate strongly dominates the film composition and the formation of the structure.

• 한국진공학회지
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• 제4권S2호
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• pp.95-99
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• 1995

keV ion beam irradiatin for surface modification and thin film growth have been discussed. keV ion beam irradiation in reactive gas environment has been developed for improving wettability of polymer, and for enhancing adhesion to metal film, and adventages of the method have been reviewed. An epitaxial Cu film on Si(100) substrate has been grown by ionized cluster beam and changes of crystallinity and surface roughness have been discussed. Stoichiometric $SnO_2$ films on Si(100) and glass have been grown by a hybrid ion beam Deposition(2 metal ion sources+1 gas ion source), and nonstoichiometric $SnO_2$ films are controlled by various deposition conditions in the HIB. Surface modification for polymer by kev ion irradiation have been developed. Wetting angle of water to PC has been changed from 68 degree to 49 degree with $Ar^+$ irradiation and to 8 degree with $Ar^+$ irradiation and the oxygen environment. Change of surface phenomena in a keV ion beam and characteristics of the grown films are suggested.

• 한국재료학회지
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• 제24권5호
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• pp.266-270
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• 2014

Aluminum nitride(AlN) films were grown on the C-face and on the Si-face of (0001) silicon carbide(SiC) substrates using plasma-assisted molecular-beam epitaxy(PA-MBE). This study was focused on first-stage growth manipulation prior to the start of AlN growth. Al pre-exposure, N-plasma pre-exposure, and simultaneous exposure(Al and N-plasma) procedures were used in the investigation. In addition, substrate polarity and, first-stage growth manipulation strongly affected the growth and properties of the AlN films. Al pre-exposure on the C-face and on the Si-face of SiC substrates prior to initiation of the AlN growth resulted in the formation of hexagonal hillocks on the surface. However, crack formation was observed on the C-face of SiC substrates without Al pre-exposure. X-ray rocking-curve measurements revealed that the AlN epilayers grown on the Si-face of the SiC showed relatively lower tilt and twist mosaic than did the epilayers grown on the C-face of the SiC. The results from the investigations reported in this paper indicate that the growth conditions on the Si-face of the SiC without Al pre-exposure was highly preferred to obtain the overall high-quality AlN epilayers formed using PA-MBE.

• 한국생산제조학회지
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• 제7권2호
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• pp.54-61
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• 1998

This paper examines the crack growth behavior of 7075-T651 aluminum alloy for small tensile overload under high-low block loading condition. The cantilever beam type specimen with a chevron notch is used in this study. The crack growth and closure are investigated by compliance method. The applied initial stress ratios are R=-0.5 R=0.0 and R=0.25 Crack length, effective stress intensity factor range, ratio of effective stress intensity factor range and crack growth rate etc, are inspected with fracture mechanics estimate.

• 한국진공학회지
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• 제18권6호
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• pp.468-473
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• 2009

Chemical beam epitaxy 성장법으로 InP/InGaAs 다층구조의 선택적 영역 에피성장 (selective area epitaxy)을 하였다. <011> 방향에 평행한 직선패턴에서는 선폭이 작아지고, <01-1> 방향에 평행한 직선패턴에서는 선폭이 증가하는 현상이 나타났는데 이는 InGaAs의 <311>A와 B면이 <01-1> 방향에 평행한 직선패턴에서 성장되었기 때문으로 설명되었다. 성장속도가 $1\;{\mu}m/h$인 조건에서 5족 가스의 압력이 감소할수록 (100) 면 위에서 평평한 에피층이 성장되었는데 이는 5족 가스의 과포화현상에 의한 3족 원소의 표면이동으로 설명하였다.