• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.137-137
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• 2008

In-situ doped polycrystalline 3C-SiC thin films were deposited by APCVD at $1200^{\circ}C$ using HMDS(hexamethyildisilane: $Si_2(CH_3)_6)$) as Si and C precursor, and 0 ~ 100 sccm $N_2$ as the dopant source gas. The peak of SiC is appeared in polycrystalline 3C-SiC thin films grown on $SiO_2$/Si substrates in XRD(X-ray diffraction) and FT-IR(Fourier transform infrared spectroscopy) analyses. The resistivity of polycrystalline 3C-SiC thin films decreased from 8.35 $\Omega{\cdot}cm$ with $N_2$ of 0 sccm to 0.014 $\Omega{\cdot}cm$ with 100 sccm. The carrier concentration of poly 3C-SiC films increased with doping from $3.0819\times10^{17}$ to $2.2994\times10^{19}cm^{-3}$ and their electronic mobilities increased from 2.433 to 29.299 $cm^2/V{\cdot}S$, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.690-693
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• 2003

An Si substrate (100) was oxidized at $400^{\circ}C$ in inductively coupled oxygen plasma. Interstitial oxygen was found in the Si substrate at the initial stage of oxidation by IR measurements. An x-ray rocking curve of Si substrates showed a lower peak intensity due to lattice distortion by the interstitial oxygen. The refractive index of thin oxides, below which interstitial oxygen existed in the Si substrate, was smaller than the refractive index of thick oxides, below which no interstitial oxygen existed. The interstitial oxygen was found by plasma oxidation using $O_{2}$ gas and $N_{2}O$ gas. The inductively coupled plasma oxidation using $N_{2}O$ gas was performed by atomic oxygen, not by molecular oxygen, indicating that atomic oxygen in plasma is responsible for the incorporation of interstitial oxygen.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.171-174
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• 1994

The drive towards ultra-large-scale integrated circuits a continuous intermetal dielectric films for multi layer interconection. Optimum condition of remote plasma enhanced chemical vapour deposition(RPECVD) was achieved by orthogonal array method. Chracteristics of SiO$_2$ films deposited by using remote PECVD with N$_2$O gas were investigated. Etching rate of SiO$_2$ films in P-echant was about 6[A/s] that was the same as the thermal oxide. The films a showed high breakdown voltage of 7(MV/cm) and a resistivity of Bx10$\^$13/[$\Omega$cm] at 7(MV/cm). The interface Trap density of SiO$_2$ has been shown excel lent properties of 5x10$\^$10/[/$\textrm{cm}^2$eV]. It was observed that the dielectric constant dropped to a value of 4. 29 for 150 [W] RF power.

• Journal of Environmental Science International
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• v.22 no.1
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• pp.73-81
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• 2013

The present work has been devoted to the catalytic reduction of $N_2O$ by $H_2$ with $Pt/SiO_2$ catalysts at very low temperatures, such as $110^{\circ}C$, and their nanoparticle sizes have been determined by using $H_2-N_2O$ titration, X-ray diffraction(XRD) and high-resolution transmission electron microscopy(HRTEM) measurements. A sample of 1.72% $Pt/SiO_2$, which had been prepared by an ion exchange method, consisted of almost atomic levels of Pt nanoparticles with 1.16 nm that are very consistent with the HRTEM measurements, while a $Pt/SiO_2$ catalyst possessing the same Pt amount via an incipient wetness technique did 13.5 nm particles as determined by the XRD measurements. These two catalysts showed a noticeable difference in the on-stream $deN_2O$ activity maintenance profiles at $110^{\circ}C$. This discrepancy was associated with the nanoparticle sizes, i.e., the $Pt/SiO_2$ catalyst with the smaller particle size was much more active for the $N_2O$ reduction. When repeated measurements of the $N_2O$ reduction with the 1.16 nm Pt catalyst at $110^{\circ}C$ were allowed, the catalyst deactivation occurred, depending somewhat on regeneration excursions.

• Korean Journal of Crystallography
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• v.18 no.1_2
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• pp.1-6
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• 2007

An Organometallic compound, $C_{16}H_{35}B_{10}IrS_2Si$, was synthesized from o-carborane, $Cp^*Ir(S_2C_2B{10}H_{10})$, and $Me_3SiCHN_2$. The molecular structure of this complex has been determined by X-ray diffraction. Crystallographic data : monoclinic, space group $P2_1/n$, $a=10.1986(12)\;{\AA}$, $b=14.834(5)\;{\AA}$, $c=17.139\;{\AA}$, ${\beta}=92.24(2)^{\circ}$, Z=4, $V=2591.0(14)\;{\AA}^3$. The structure was solved by direct methods and refined by full-matrix leat-squares methods to give a model with a reliability factor R=0.053 for 5080 reflections.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.5
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• pp.12-17
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• 2011

In this work, the analog performances of n-MOSFET fabricated on strained-Si/relaxed Si buffer layer with Ge mole fractions and thermal annealing temperatures after device fabrication have been characterized in Depth. The effective electron mobility was increased with the increase of Ge mole fraction for all annealing temperatures. However the effective electron mobility was decreased at the Ge mole fraction of 32%. The analog performances were enhanced with the increase of Ge mole fraction at the room temperature but they were degraded at the Ge mole fraction of 32%. Since the degradation of the effective electron mobility of strained-Si layer is more significant than one of conventional Si layer at elevated temperature, the degradation of analog performances of SGOI devices were increased than those of SOI devices.

• Korean Journal of Materials Research
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• v.14 no.2
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• pp.141-145
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• 2004

Silicon nitride thin films were deposited by atomic layer deposition (ALD) technique in a batch-type reactor by alternating exposures of precursors. XJAKO200414714156408$_4$ or$ SiH_2$$Cl_2$ was used as the Si precursor, $NH_3$ was used as the N precursor, and the deposited films were characterized comparatively. The thickness of the film linearly increased with the number of deposition cycles, so that the thickness of the film can be precisely controlled by adjusting the number of cycles. As compared with the deposition using$ SiCl_4$, the deposition using $SiH_2$$Cl_2$ exhibited larger deposition rate at lower precursor exposures, and the deposited films using $SiH_2$$Cl_2$ had lower wet etch rate in a diluted HF solution. Silicon nitride films with the Si:N ratio of approximately 1:1 were obtained using either Si precursors at $500^{\circ}C$, however, the films deposited using $SiH_2$$Cl_2$ exhibited higher concentration of H as compared with those of the $SiC_4$ case. Silicon nitride thin films deposited by ALD showed similar physical properties, such as composition or integrity, with the silicon nitride films deposited by low-pressure chemical vapor deposition, lowering deposition temperature by more than $200^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.35 no.1
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• pp.33-38
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• 2002

For the evaluation of nucleation and growth behaviors influenced by substrate properties, such as surface energy, structure and electrical properties, chromium nitride films (CrN) were deposited on various substrates (glass, AISI 1040 steel and Si (110) by unbalanced magnetron sputtering. X-ray diffraction and Atomic Force Microscopy (AFM) were used to study the microstructure and grain growth as a function of deposition time. The diffraction patterns of CrN thin films deposited on Si (110) exhibited crystalline structure with highly preferred orientation of (200) plane parallel to the substrate, whereas the films deposited on glass and AISI 1040 exhibited preferred orientations (200) and minor orientation (111), (311) or (220) plane. The orientation of films deposited both on glass and Si substrates did not depend on the bias voltage (Vs). The grain growth and structure of film deposited on AISI 1040 steel substrate are strongly influenced by the substrate bias in comparison with that deposited onto glass and Si substrates. The differences in the structure and grain growth of CrN films deposited onto different substrates are predominantly related to the properties of the substrate (structure and electrical conductivity).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.88-91
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• 2003

Si nanocrystallites thin films have been fabricated by pulsed laser deposition using a Nd:YAG laser. After deposition, samples were annealed at the temperature range of 400 to $800^{\circ}C$. Hydrogen passivation was then performed in the forming gas ($95%N_{2}+5%H_{2}$) at $500^{\circ}C$. Strong violet-indigo photoluminescence has been observed at room temperature on nitrogen ambient-annealed Si nanocrystallites. As a result of photoluminescence spectra and infrared absorption spectra, we conclude that the violet-indigo PL efficiency is related with oxygen vacancy in the $SiO_x$(x= 1.6-1.8) matrix.

• Solar Energy
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• v.11 no.1
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• pp.41-49
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• 1991

In this study, the (P)SiC/(N)Si solar cell is fabricated by the vacuum evaporation method with the substrate temperature at about $200{\pm}5[5^{\circ}C]$ and its characteristics are investigated. The optimal thickness of $1.2[{\mu}m]$ of SiC film is derived from the relation between film thickness and conversion efficiency. The characteristics of solar cells are improved by the annealing. The optimum annealing temperature and duration are $420[^{\circ}C]$ and 12[min], respectively it is shown that the peak values of spectral response are shifted to the long wavelength region with increasing the annealing temperature. The X-ray diffraction patterns and the scanning electron micrographs show the grain grow thin SiC film as the annealing temperature and time is increased. The best conversion efficiency is 11.7[%] for a $2.5{\times}1[cm^2]$ cell.