• Transactions on Electrical and Electronic Materials
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• v.4 no.5
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• pp.33-37
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• 2003

This study was performed to investigate the deposition mechanism of SiO$_2$ by ArF excimer laser(l93nm) CVD with Si$_2$H$\_$6/ and N$_2$O gas mixture and evaluate laser CVD quantitatively by modeling. With ArF excimer laser CVD, thin films can be deposited at low temperature(below 300$^{\circ}C$), with less damage and good uniformity owing to generation of conformal reaction species by singular wavelength of the laser beam. In this study, new model of SiO$_2$ deposition process by laser CVD was introduced and deposition rate was simulated by computer with the basis on this modeling. And simulation results were compared with experimental results measured at various conditions such as reaction gas ratio, chamber pressure, substrate temperature and laser beam intensity.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.139.2-139.2
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• 2013

6" Multi-crystal Silicon wafer has etched suing a remote - type RF Dielectric barrier discharge (RF DBD) at atmospheric pressure. DBD source is composed of Al electrode and coated Al2O3 dielectric as function of Ar/NF3 gas combination and input power used 13.56 MHz power supply. Ar gas flow rate is changed from 2 to 10 Slm, and NF3 flow rate is changed from 0.2~1 slm. At the result, NF3 flow rate Si etching rate also increase whit the increasing of NF3 flow rate But at 2 slm etching rate was decrease. In this experience, Max etching rate is 2.3 ${\mu}m/min$ when the scan time is 45 sec.

• Fire Science and Engineering
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• v.18 no.1
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• pp.7-12
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• 2004

For CFCs and Halons regulated by Montreal Protocol and their alternatives of HFC-23, HFC-125 HFC-227ea, HFC-236fa and the mixtures of inert gases of $Ar, N_2 and CO_2$, the thermodynamic properties of saturated pressure, density, enthalpy and viscosity were compared. In this study, the data from literature were expressed as a function of temperature. Thermodynamic properties of HFC compounds were similar to those of Halon-1301. Inert gas was mainly used as a mixture, but the physical properties of the inert gas does not have the favorable advantages over those of Halon-1301.

• Bulletin of the Korean Chemical Society
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• v.16 no.2
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• pp.101-104
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• 1995

In an attempt to understand the nature of hyperthermal ion-surface collisions, noble gas ion beams (He+, Ne+, Ar+, and Xe+) are scattered from a Si(100) surface for collision energies of 20-300 eV and for 45°incidence angle. The scattered ions are mass-analyzed using a quadrupole mass spectrometer and their kinetic energy is measured in a time-of-flight mode. The scattering event for He+ and Ne+ can be approximated as a sequence of quasi-binary collisions with individual Si atoms for high collision energies (Ei > 100 eV), but it becomes of a many-body nature for lower energies, Ar+ and Xe+ ions undergo mutliple large impact parameter collisions with the surface atoms. The effective mass of a surface that these heavy ions experience during the collision increases drastically for low beam energies.

• Bulletin of the Korean Chemical Society
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• v.12 no.6
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• pp.652-658
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• 1991

The effect of intermolecular collisions in the infrared multiphoton dissociation (IRMPD) of difluorochloromethane was investigated using He, Ar, and $N_2$ as buffer gases. The reaction probability for IRMPD of difluorochloromethane was measured as a function of laser fluence and the buffer gas pressure under unfocused beam geometry. It was observed that the reaction probability was initially enhanced with the increase of buffer gas pressure up to about 20 torr, but showed a decline at higher pressures. The reaction probability increases monotonically with the laser fluence, but the rate of increase diminishes at higher fluences. An attempt was made to simulate the experimental results by the method of energy grained master equation (EGME). From the parameters that fit the experimental data, the average energy loss per collision, $<{\Delta}E>_d$, was estimated for the He, Ar, and $N_2$ buffer gases.

• ETRI Journal
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• v.30 no.3
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• pp.383-393
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• 2008

The etching mechanism of $ZrO_2$ thin films and etch selectivity over some materials in both $BCl_3$/Ar and $BCl_3/CHF_3$/Ar plasmas are investigated using a combination of experimental and modeling methods. To obtain the data on plasma composition and fluxes of active species, global (0-dimensional) plasma models are developed with Langmuir probe diagnostics data. In $BCl_3$/Ar plasma, changes in gas mixing ratio result in non-linear changes of both densities and fluxes for Cl, $BCl_2$, and ${BCl_2}^+$. In this work, it is shown that the non-monotonic behavior of the $ZrO_2$ etch rate as a function of the $BCl_3$/Ar mixing ratio could be related to the ion-assisted etch mechanism and the ion-flux-limited etch regime. The addition of up to 33% $CHF_3$ to the $BCl_3$-rich $BCl_3$Ar plasma does not influence the $ZrO_2$ etch rate, but it non-monotonically changes the etch rates of both Si and $SiO_2$. The last effect can probably be associated with the corresponding behavior of the F atom density.

• Korean Journal of Materials Research
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• v.15 no.8
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• pp.518-520
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• 2005

Effects of the $O_2/Ar$ flow ratio in the sputtering process on the crystallinity, surface roughness, carrier concentration, carrier mobility, and optical properties of Al-doped ZnO thin films deposited on sapphire (001) substrates by RF magnetron sputtering were investigated. XRD spectra showed a preferred orientation along the c-axis and a minimum FWHM of the (002) XRD intensity peak for the $O_2/Ar$ flow ratio of 0.5. The (101)peak also appeared and the degree of preferred orientation decreased as the $O_2/Ar$ flow ratio increased from 0.5 to 1.0. AFM analysis results showed that the surface roughness was lowest at the $O_2/Ar$ flow ratio of 0.5 and tended to increase owing to the increase of the grain size as the $O_2/Ar$ flow ratio increased further. According to the Hall measurement results the carrier concentration and carrier mobility of the fan decreased and thus the resistivity increased as the $O_2/Ar$ flow ratio increased. The transmittance of the ZnO:Al film deposited on the glass substrate was characteristic of a standing wave. The transmittance increased as the $O_2/Ar$ flow ratio in-RF magnetron sputtering increased up to 0.5. Considering the effects of the $O_2/Ar$ flow ratio on the surface roughness, electrical resistivity and transmittance properties of the ZnO:Al film the optimum $O_2/Ar$ flow ratio was 0.5 in the RF magnetron sputter deposition of the ZnO:Al film.

• Journal of the Korean institute of surface engineering
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• v.39 no.3
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• pp.137-141
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• 2006

Process window for infinite etch selectivity of silicon nitride $(Si_3N_4)$ layers to ArF photoresist (PR) was investigated in dual frequency superimposed capacitive coupled plasma (DFS-CCP) by varying the process parameters such as low frequency power $(P_{LF})$, $CH_2F_2$ and $H_2$ flow rate in $CH_2F_2/H_2/Ar$ plasma. It was found that infinite etch selectivities of $Si_3N_4$ layers to the ArF PR on both blanket and patterned wafers can be obtained for certain gas flow conditions. The etch selectivity was increased to the infinite values as the $CH_2F_2$ flow rate increases, while it was decreased from the infinite etch selectivity as the $H_2$ flow rate increased. The preferential chemical reaction of the hydrogen with the carbon in the polymer film and the nitrogen on the $Si_3N_4$ surface leading to the formation of HCN etch by-products results in a thinner steady-state polymer and, in turn, to continuous $Si_3N_4$ etching, due to enhanced $SiF_4$ formation, while the polymer was deposited on the ArF photoresist surface.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.816-820
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• 2007

We measured the electron drift velocity, W, in 0.5% $SF_6-Ar$ mixture over the E/N range from 30 Td to 300 Td and gas pressure range from 0.1 to 0.5 Torr by the double shutter drift tube with a variable drift distance, and calculated over the same E/N and gas pressure range by using the two-term approximation of the Boltzmann equation. The measured and calculated values at different gas pressure at each E/N was appreciable dependence in the results on the gas pressure.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.4
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• pp.632-640
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• 2004

The purpose of this study is to clarify the influence of inert gas on the configuration characteristics of premixed turbulent propagating flames of hydrogen mixtures. Inert gas is changed to $N_2$, Ar, $CO_2$ and He keeping the laminar burning velocity of mixtures nearly the same value. A laser tomography technique was used to obtain the flame shape, and quantitative analyses were performed. The result shows that in the wrinkled laminar flame region, the surface area of turbulent flame is slightly dependent on the equivalence ratio and the kind of inert gas. It is also shown the region of convex part of flame toward the unburned gas is greater than that of toward the burned gas regardless of the kind of inert gas.