• Electrical & Electronic Materials
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• v.9 no.7
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• pp.727-732
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• 1996

In the present paper, the Cu films 4.mu.m thick were deposited by RF magnetron sputtering method on Si wafer. The Cu films deposited at a condition of 100W, 10mtorr exhibited a low electrical resistivity of 2.3.mu..ohm..cm and densed microstructure, poor adhesion. The Cu films grown by 200W, 20mtorr showed a good adhesion property and higher electrical resistivity of 7.mu..ohm..cm because of porous columnar microstructure. Therefore, The Cu films were deposited by double layer deposition method using RF magnetron sputtering on Si wafer. The dependence of the electrical resistivity, adhesion, and reflectance in the CU films [C $U_{4-d}$(low resistivity) / C $U_{d}$(high adhesion) / Si-wafer] on the thickness of d has been investigated. The films formed with this deposition methods had the low electrical resistivity of about 2.6.mu..ohm..cm and high adhesion of about 700g/cm.m.m.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.178-178
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• 2010

We have deposited aluminum-doped ZnO thin films on borosilicate glass by atomic layer deposition. Diethylzinc (DEZ) and dimethylaluminum isopropoxide (DMAIP) were used as the metal precursor and the Al-dopant, respectively. Water was used as an oxygen source. DMAIP was successfully used as an aluminum precursor for chemical vapor deposition and ALD. All deposited films showed n-type conduction. The resistivity decreased to a minimum and then increased with increasing the aluminum content. The carrier concentration increased and the carrier mobility decreased with increasing the DMAIP to DEZ pulse ratio. The average optical transmittance was nearly 80 % in the visible part of the spectrum. The absorption edge moved to the shorter wavelength region with increasing the DMAIP to DEZ pulse ratio. Our results indicate that DMAIP is suitable for Al doping of ZnO films.

• Journal of Surface Science and Engineering
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• v.37 no.5
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• pp.243-248
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• 2004

A palladium-nikel(Pd-Ni) alloy composite membrane has been fabricated on microporous nickel support formed with nickel powder. Plasma surface treatment process is introduced as pre-treatment process instead of HCI activation. Pd coating layer was prepared by dc magnetron sputtering deposition after $H_2$ plasma surface treatment. Palladium-nickel alloy composite layer had a fairly uniform and dense surface morphology. The membrane was characterized by permeation experiments with hydrogen and nitrogen gases at temperature of 773 K and pressure of 2.2psi. The hydrogen permeance was 6 ml/minㆍ$\textrm{cm}^2$ㆍatm and the selectivity was 120 for hydrogen/nitrogen($H_2$/$N_2$) mixing gases at 773 K.

• Applied Microscopy
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• v.48 no.4
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• pp.122-125
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• 2018

The focused ion beam (FIB) method is widely used to prepare specimens for observation by transmission electron microscopy (TEM), which offers a wide variety of imaging and analytical techniques. TEM has played a significant role in material investigation. However, the FIB method induces amorphization due to bombardment with the high-energy gallium ($Ga^+$) ion beam. To solve this problem, electron beam induced deposition (EBID) is used to form a protective layer to prevent damage to the specimen surface. In this study, we introduce an optimized TEM specimen preparation procedure by comparing the EBID of carbon and tungsten as protective layers in FIB. The selection of appropriate EBID conditions for preparing specimens for TEM analysis is described in detail.

• Journal of the Korean Ceramic Society
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• v.34 no.4
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• pp.373-379
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• 1997

A study on the deposition and characterization of BaTiO3 thin films on MgO-buffered Si(100) substrates by sputtering was conducted. The MgO buffer layers were investigated as a function of deposition temperature. At lower substrate temperature, the MgO layers were not fully crystalline, but a crystallized MgO layer with (001) preferred orientation was obtained at the substrate temperature of $700^{\circ}C$. Partially (00ι) or (h00) textured BaTiO3 films were obtained on Si(100) with the MgO buffer layer grown at 700ι. While, randomly oriented BaTiO3 films with large-scale cracks on the surface were made without the MgO layer. The crystallographic orientation, morphology and electrical properties between the BaTiO3 films on Si with and without the MgO layer were compared using the BaTiO3 film on MgO(100) single crystal substrate as a reference system. Also the favorable role of the MgO layer as a buffer for growing of oriented BaTiO3 films on Si substrates was confirmed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.242-242
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• 2010

산화 알루미늄($Al_2O_3$) 박막을 p-type Czochralski(CZ) Si 위에 Remote Plasma Atomic Layer Deposition(RPALD)을 이용하여 저온 공정으로 증착하였다. Photolithography 공정으로 grid 패턴을 형성한 후 열 증착기로 알루미늄을 증착하여 MIS-IL (Metal-Insulator-Semiconductor Inversion Layer) solar cell을 제작하였다. 반응소스로는 Trimethylaluminum (TMA)과 $O_2$를 이용하였다. $Al_2O_3$ 박막의 전기적 특성 평가를 위해 MIS capacitor를 제작하여 Capacitance-voltage (C-V), Current-voltage (I-V), Interface state density ($D_{it}$)를 평가하였으며 Solar simulator를 이용하여 MIS-IL Solar cell의 Efficiency을 측정하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.15-16
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• 2008

In case manufacturing COF, through hole should be made to be used for a pathway connecting the conductive layers of its both faces. In case Cu-plating inside of through hole with electroless plating way, contact between Cu and PI film gets bad to be fell apart from PI by the impact of applying to the electric devices. Therefore, after sputtering is applying on inner through hole, then a method to perform electroplating process. In this study, after changing sputtering condition to manufacture FCCL, we looked the changeability of the upper PI and inner hole Cu layers. Making use of RF Magnetron sputtering equipment, we coated Cu thin film and Cu-plated on it through electroplating. After cold-mounting the completed FCCL, we examined hole section through an optical microscope. From the result of test, with parameters deposition pressure and deposition time, both the thickness of the hole plated layer and PI plated upper layer increased at regular rate, increasing the thickness of Cu sputter layer. However, from the result of test in increasing RF-power, we could know the increment rate of hole plated layer is considerably greater than that of PI plated upper layer. Therefore, we finally acquired good result; if you want only to increase the plated layer of inner hole, it's much better to increase RF-power.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.9-10
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• 2007

In this paper, Thin films of $HfO_2$/Hf were deposited on p-type wafer by Atomic Layer Deposition(ALD). And we studied the electrical characterization of $HfO_2$/Hf/Si MOS capacitor depending on thickness of Hf metal layer. $HfO_2$ films were deposited using TEMAH and $O_3\;at\;350^{\circ}C$. Samples were then annealed using furnace heating to $500^{\circ}C$. The MOS capacitor of round-type was fabricated on Si substrates. Through TEM(Transmission Electron Microscope), XRD(X-ray Diffraction), capacitance-voltage(C-V) and current-voltage(I-V) analysis, the role of thin Hf metal layer for the better $HfO_2$/Si interface property was investigated.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.152-153
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• 2006

The new approach to buffer layer design for CIGS solar cells that permitted to reduce the buffer absorption losses in the short wavelength range and to overcome the disadvantages inherent to Cd-free CIGS solar cells was proposed. A chemical bath deposition method has been used to produce a high duality buffer layer that comprises thin film of CdS and Zn-based film. The double layer was grown on either ITO or CIGS substrates and its morphological, structural and optical properties were characterized. The Zn-based film was described as the ternary compound $ZnS_x(OH)_y$. The composition of the $ZnS_x(OH)_y$ layer was not uniform throughout its thickness. $ZnS_x(OH)_y$/CdS/substrate region was a highly intermixed region with gradually changing composition. The short wavelength cut-off of double layer was shifted to shorter wavelength (400nm) compared to that (520 nm) for the standard CdS by optimization of the double buffer design. The results show the way to improve the light energy collection efficiency of the nearly cadmium-free CIGS-based solar cells.

• Current Photovoltaic Research
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• v.9 no.4
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• pp.137-144
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• 2021

In this study, the microstructure of the CVD-fabricated Cu(In,Ga)Se₂ (CIGSe) absorber layer by simulating the stacking sequence used in a co-evaporation method, and changes solar cell performance were investigated. The absorber layer prepared by stacking CuSe and (In,Ga)Se between InSe is separated into Ga-free CuInSe₂ and Ga-rich CIGSe, and transformed to CIGSe by selenization heat treatment with slight improvement in the the solar cell efficiency. However, in CVD, since the supply of liquid Cu-Se is not as active as in the co-evaporation method, the nanoocrystalline layer containing a large amount of Ga remained independently in the absorption layer, which acted as a cause of the loss of J_SC and FF. Therefore, by using a precursor structure in which CuGa is sputter-deposited on a single layer of InSe deposited by CVD, performance parameters of V_OC, J_SC, and FF could be greatly improved.