• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.459-460
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• 2008

Zinc oxide micro rods were fabricated using as chemical bath deposition ok photolithography. Vertically aligned Zinc Oxide rod array as grown by chemical bath deposition method on Zinc Oxide template layer. The ZnO template layer was deposited on glass and the pattering was made by standard photolithography technique. The selective growth of ZnO micro rods were achieved with the masked ZnO template layer substrate. The fabricated ZnO micro rods were found to be single crystalline and have grown along hexagonal c-axis direction of (0002) which is same as the preferred growth orientation of ZnO template layer. The ZnO micro-rod array structure was implemented as a window layer in Cu(InGa)Se2 solar cell and its effect on photovoltaic efficiency was examined.

• 한국결정성장학회지
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• 제4권1호
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• pp.57-62
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• 1994

FZ법을 이용하여 $YbFeCoO_4$ 단결정을 성장하였다. 결정 성장은 공기분위기 중에서 이루어졌으며, 성장 속도는 1~2mm/hr로 조절하였으며, 성장 초기는 $YbReO_3$와 CoO로 분해 되었으나 용융 후 액상의 조성이 변화됨에 따라 $YbFeCoO_4$ 단일사의 단결정이 육성되었다.결정의 성장 방향은 c축에 수직으로 성장하였으며 다결정의 종자 결정을 이용하여 용이성장축으로 성장된 결정의 성장 방향은[110]방향이었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.27.1-27.1
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• 2009

In recent years, ZnO nanostructures have drawn considerable attentions for the development of futuristic electronic devices due to their superior structural and optical properties. As the growth of ZnO nanowires by MOCVD is a bottom-up technique, the nature of substrates has a vital role for the dimension and alignment of the nanowires. However, in the pursuit of next generation ZnO based nanodevices, it would be highly preferred if well-ordered ZnO nanowires could be obtained on various substrates like sapphire, silicon, glass etc. Vertically aligned nanowires were grown on A and C-plane sapphire substrates, where as nanopencils were obtained on R-plane sapphire substrates. In addition, C-axis oriented vertical nanowires were also found using an interfacial layer(aluminum nitride film) on silicon substrates. On the other hand, long nanowires were found on Ga-doped ZnO film on glass substrates. Structural and optical properties of the ZnO nanowires on various substrates were also investigated.

• 한국전기전자재료학회논문지
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• 제13권10호
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• pp.828-833
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• 2000

Growth characteristics and microstructure of AIN thin films grown by plasma assisted molecular beam epitaxy on Si substrates have been investigated. Growing temperature and substrate orientation were chosen as major variables of the experiment. Reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy/diffraction (TEM/TED) techniques were employed to characterize the micorstructure of the films. On Si(100) substrates, AlN thin films were grown along the hexagonal c-axis preferred orientation at temperature range 850-90$0^{\circ}C$. However on Si(111), the AlN films were epitaxially grown with directional coherency in AlN(0001)/Si(111), AlN(1100)/Si(110), and AlN(1120)/Si(112) at 85$0^{\circ}C$ and the epitaxial coherencry seemed to be slightly distorted with increasing temperature. The microstructure of AlN thin films on Si(111) substrates showed that the films include a lot of crystal defects and there exist micro-gaps among the columns.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.111-114
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• 2000

Growth characteristics and microstructure of AlN thin films grown by plasma assisted molecular beam epitaxy on Si substrates have been investigated. Growing temperature and substrate orientation were chosen as major variables of the experiment. Reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy/diffraction (TEM/TED) techniques were employed to characterize the microstructure of the films. On Si(100) substrates, AlN thin films were grown along the hexagonal c-axis preferred orientation at temperature range 850-90$0^{\circ}C$. However on Si(111), the AlN films were epitaxially grown with directional coherency in AlN(0001)/Si(111), AlN(1100)/Si(110), and AlN(1120)/Si(112) at 85$0^{\circ}C$ and the epitaxial coherencry seemed to be slightly distorted with increasing temperature. The microstructure of AlN thin films on Si(111) substrates showed that the films include a lot of crystal defects and there exist micro-gaps among the columns.

• 한국자기학회지
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• 제19권4호
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• pp.126-132
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• 2009

Molecular-Beam Epitaxy 방법으로 합성된 MnAs 박막의 물리적 특성을 기판의 종류와 증착 온도에 따라 조사하였으며 더불어 이들 시료의 증착 후 열처리 효과를 조사하였다. 증착 온도가 $600^{\circ}C$일 경우에는 기판의 종류에 관계없이 type-B의 결정 방향성을 보였으나 $200^{\circ}C$ 이하에서 합성한 시료에 대하여는 type-A로 합성되었다. $600^{\circ}C$에서 GaAs(001) 기판에 성장시킨 시료에서는 자기화 용이축 내에서도 특히 한쪽 방향으로 자화가 되어 있음을 확인하였다. 강자성을 보이지 않던 $120^{\circ}C$에서 증착한 MnAs/Si(001)와 실온에서 강자성과 상자성이 공존하였던 $200^{\circ}C$에서 증착한 MnAs/GaAs(001) 시료의 경우 $600^{\circ}C$에서 열처리 하였을때 자기적 특성이 크게 향상되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.415-415
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• 2012

ZnO nanostructures were synthesized by a vapor phase transport process in a single-zone furnace within a horizontal quartz tube with an inner diameter of 38 mm and a length of 485 mm. The ZnO nanostructures were grown on Au-catalyzed Si(100) substrates by using a mixture of zinc oxide and graphite powders. The growth of ZnO nanostructures was conducted at $800^{\circ}C$ for 30 min. High-purity Ar and $O_2$ gases were pushed through the quartz tube during the process at a flow rate of 100 and 10 sccm, respectively. The sequence of ON/OFF cycles of the Ar gas flow was repeated, while the $O_2$ flow is kept constant during the growth time. The Ar gas flow was ON for 1 min/cycle and that was OFF for 2 min/cycle. The structure and optical properties of the ZnO nanostructures were investigated by field-emission scanning electron microscope, X-ray diffraction, temperature-dependent photoluminescence. The preferred orientation of the ZnO nanostructures was along c-axis with hexagonal wurtzite structure.

• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.219-222
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• 2007

Highly conductive and transparent aluminum doped ZnO thin films (AZO) films have been prepared by r.f. magnetron sputtering processes on poly carbonate (PC) and onto glass as reference. In addition, the electrical, optical properties of the films prepared at various sputtering powers were investigated. The XRD measurements revealed that all of the obtained films were polycrystalline with the hexagonal structure and had a preferred orientation with the c-axis perpendicular to the substrate. The ZnO:Al films were increasingly dark gray colored as the sputter power increased, resulting in the loss of transmittance. High quality films with the resistivity as low as $9.7{\times}10^{-4}\;{\Omega}-cm$ and transmittance over 90% have been obtained by suitably controlling the r.f. power.

• 한국표면공학회지
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• 제41권4호
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• pp.142-146
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• 2008

Trivalent ions(Ga, Al, In) doped ZnO films were deposited by DC magnetron sputtering on non-alkali glass substrate at substrate temperature of $300^{\circ}C$. We used the different three types of high density($95%{\sim}$) ceramic sintered disks(doped with $Ga_2O_3$; 6.65 wt%, $Al_2O_3$; 3.0 wt%, $In_2O_3$; 9.54 wt%). This study examined the effect of different dopants(Ga, Al, In) on the electrical, structural, and optical properties of the films. The lowest resistivity of $5.14{\times}10^{-4}{\Omega}cm$ and the highest optical band gap of 3.74 eV were obtained by Ga doped ZnO(GZO) film. All the films had a preferred orientation along the(002) direction, indicating that the growth orientation has a c-axis perpendicular to the substrate surface. The average transmittance of the films was more than 85% in the visible range.

• 한국표면공학회지
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• 제42권3호
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• pp.122-127
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• 2009

Ga/Al doped ZnO (GAZO) thin films were prepared on non-alkali glass substrate by co-sputtering system using two DC cathodes equipped with AZO ($Al_2O_3$:2.0 wt%) target and GZO ($Ga_2O_3$:6.65 wt%) target. This study examined the influence of Al/Ga concentration and substrate temperature on the electrical, structural and optical properties of GAZO films. The lowest resistivity $1.95{\times}10^{-3}{\Omega}cm$ was obtained at room temperature. With increasing substrate temperature, resistivity of GAZO film decreased to a minimum value of $7.47{\times}10^{-4}{\Omega}cm$ at below $300^{\circ}C$. Furthermore, when 0.05% $H_2$ gas was introduced, resistivity of GAZO film decreased to $6.69{\times}10^{-4}{\Omega}cm$. All the films had a preferred orientation along the (002) direction, indicating that the deposited films have hexagonal wurtzite structure formed by the textured growth along the c-axis. The average transmittance of the films was more than 85% in the visible light range.