• Proceedings of the Materials Research Society of Korea Conference
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• 1999.05a
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• pp.116-116
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• 1999

• Journal of the Korean Vacuum Society
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• v.19 no.3
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• pp.177-183
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• 2010

We report on the deposition of ZnO films using a metal organic chemical vapor deposition (MOCVD) as a function of pushing pressure and kind of reactant such as oxygen gas and water A diethylzinc (DEZ) is supplied and controlled by Ar pushing pressure through bubbling system. Oxygen gas and water are used as reactant in order to form oxidation. We knew that the surface roughness is related in the process conditions such as reactant kind and DEZ flow rate. A substrate temperature has little role of surface roughness with $O_2$ reactant. However, $H_2O$ reactant makes it to increase over the 20 times. We could get the maximum roughness of 39.16 nm at the 90 sccm of DEZ Ar flow rate, the 8 Pa of $H_2O$ vapor pressure, and the $140^{\circ}C$ of substrate temperature. In this paper, we investigated the ZnO films for the application to the light absorption layer of solar cell layer.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.829-832
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• 2005

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.953-956
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• 2003

Hexagonal GaN (h-GaN) films have been grown on Si(111) substrates by metal organic chemical vapor deposition using the azidodiethylgallium methylamine adduct, Et₂Ga(N₃)·NH₂Me, as a new single precursor. Deposition was carried out in the substrate temperature range 385-650 °C. The GaN films obtained were stoichiometric and did not contain any appreciable amounts of carbon impurities. It was also found that the GaN films deposited on Si(111) had the [0001] preferred orientation. The photoluminescence spectrum of a GaN film showed a band edge emission peak characteristic of h-GaN at 378 nm.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.225-228
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• 2002

Amorphous $Ga_2O_3$ films have been grown on Si(100) substrates by metal organic chemical vapor deposition (MOCVD) using gallium isopropoxide, $Ga(O^iPr)_3$, as single precursor. Deposition was carried out in the substrate temperature range 400-800 $^{\circ}C$. X-ray photoelectron spectroscopy (XPS) analysis revealed deposition of stoichiometric $Ga_2O_3$ thin films at 500-600 $^{\circ}C$. XPS depth profiling by $Ar^+$ ion sputtering indicated that carbon contamination exists mostly in the surface region with less than 3.5% content in the film. Microscopic images of the films by scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed formation of grains of approximately 20-40 nm in size on the film surfaces. The root-mean-square surface roughness from an AFM image was ${\sim}10{\AA}$. The interfacial layer of the $Ga_2O_3$/Si was measured to be ${\sim}35{\AA}$ thick by cross-sectional transmission electron microscopy (TEM). From the analysis of gaseous products of the CVD reaction by gas chromatography-mass spectrometry (GC-MS), an effort was made to explain the CVD mechanism.

• Journal of the Optical Society of Korea
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• v.20 no.1
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• pp.125-129
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• 2016

In this study, we have investigated a high-temperature AlN nucleation layer and AlGaN epilayers on c-plane sapphire substrate by low-pressure metal-organic chemical vapor deposition (LP-MOCVD). High resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM), scanning electron microscope (SEM) and Raman scattering measurements have been exploited to study the crystal quality, surface morphology, and residual strain of the HT-AlN nucleation layer. These analyses reveal that the insertion of an LT-AlN nucleation layer can improve the crystal quality, smooth the surface morphology of the HT-AlN nucleation layer and further reduce the threading dislocation density of AlGaN epifilms. The mechanism of inserting an LT-AlN nucleation layer to enhance the optical properties of HT-AlN nucleation layer and AlGaN epifilm are discussed from the viewpoint of driving force of reaction in this paper.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.6
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• pp.582-586
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• 2005

We have grown GaN layers with in-situ SiN mask by metal organic chemical vapor deposition (MOCVD) and study the physical properties of the GaN layer. We have also investigate the effect of the SiN mask on its optical property. By inserting a SiN mask, (102) the full width at half maximum (FWHM) decreased from 480 arcsec to 409 arcsec and threading dislocation (TD) density decreased from $3.21\times10^9\;cm^{-2}\;to\;9.7\times10^8\;cm^{-2}$. The PL intensity of GaN with SiN mask improved 2 times to that without SiN mask. We have thus shown that the SiN mask improved significantly the physical and optical properties of the GaN layer.

• Journal of the Korean Ceramic Society
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• v.33 no.9
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• pp.969-976
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• 1996

RuO2 thin films were deposited on SiO2(1000 $\AA$)/Si by hot-wall Metal Organic Chemical Vapor Depositon. The crystallinity of RuO2 thin films increased with increasing deposition temperature and the preferred orienta-tion of RuO2 films converted (200) plane to (101) plane with increasing film thicknesses. Such a change in preferred orientation was influenced on the crystallographic structure and the residual stress of RuO2 thin films. The resistivity of the 2700$\AA$-thick RuO2 thin films deposted at 30$0^{\circ}C$ was 52.7$\mu$$\Omega$-cm and they could be applicable to bottom electrodes of high dielectric materials. However the resistivity of RuO2 thin films increased with decreasing film thicknesses. The grain size and the resistivity of RuO2 thin films were densified with increasing the annealing temperature and showed the decrease of resistivity.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2003.12a
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• pp.45-49
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• 2003

본 논문에서는 gate 산화막을 위한 Hf oxide 박막을 $Hf(dmae)_4$ (dmae=dimethylaminoethoxide) 전구체로 Direct Liquid Injection Metal Organic Chemical Vapor Deposition (DLI-MOCVD)방법을 이용하여 p-type Si(100) 기판 위에 증착하였다. 이 전구체를 이용하여 $150^{\circ}C$의 낮은 증착 온도에서도 낮은 carbon 농도와 roughness를 가지는 양질의 박막을 증착할 수 있었다. 증착된 박막은 비정질 구조를 나타내었지만 annealing 온도를 증가시킴에 따라서 결정성(monoclinic phase)을 나타내었다. $500{\AA}$으로 증착한 박막을 C-V 와 I-V curve를 통하여 전기적 특성을 평가하였다. 열처리 온도가 증가함에 따라 유효유전상수(k)는 증가하지만 열처리 온도가 $900^{\circ}C$ 이상이 되면 계면층의 형성에 의해 유효유전상수는 감소하게 되고 이에 따라 누설 전류도 감소하게 된다. 산소분위기 $800^{\circ}C$에서 annealing한 $HfO_2$ 박막의 유전상수는 20.1이고, 누설 전류 밀도는 SV에서 $2.2\times10^{-6}A/\textrm{cm}^2$ 로 좋은 전기적 특성을 가진다.

• Journal of the Korean Ceramic Society
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• v.37 no.11
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• pp.1126-1129
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• 2000

The crystallographic orientations of $Ba_{0.6}$S $r_{0.4}$Ti $O_3$(BST) thin film deposited by a metal-organic chemical vapor deposition on (111) textured Pt electrode were studied with a transmission electron microscopy. The fully crystallized BST thin film (50nm) has (100) and (110) preferred orientations. A high resolution transmission electron microscopy study has revealed the crystallographic orientation relationships between BST thin film and Pt electrode. These relationships explained the preferred orientation of BST film on (111) textured Pt electrode. With these results, we could represent the atomic arrangement at the BST/Pt interface.e.e.