• Journal of Korean Society for Atmospheric Environment
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• v.16 no.2
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• pp.165-178
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• 2000

In this study the effects of block distance have been investigated on the particle deposition efficiency in the collecting cell of two-stage electrostatic precipitator by numerical analysis. Particle trajectories have been changed by the electrostatic and inertial force of particle with the inlet velocity electrostatic number and particle diameter. The total deposition efficiency has a minimum value by the interaction between the effect of particle inertial force and electrostatic force in the collecting cell. The increase of block distance makes the total deposition efficiency decrease under the range of the particle size which has the minimum deposition efficiency. However beyond the range of particle size which has minimum deposition efficiency total deposition efficiency has no trend with the variation of block distance.

• Journal of ILASS-Korea
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• v.11 no.1
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• pp.7-16
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• 2006

Performance of thin films fabricated with the electrostatic spray deposition (ESD) technique is strongly governed by surface morphology, which depends on deposition parameters such as deposition time and temperature, solution properties, and surface characteristics of substrates. In this article, the state of the art on the relationships between the surface morphology and the deposition parameters is presented. Also studies on the electro-hydrodynamic atomization process and the motion of drops relevant to the ESD technique are briefly reviewed, and the future research works are suggested.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.12
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• pp.1033-1038
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• 2006

We carried out the experiments on particle deposition onto the cleanroom wall panels. And then we investigated the particle deposition characteristic coefficients for electrostatic voltages and particle size. It was found that there is little difference in characteristics of the particle deposition between the steel panel and the anti-static coating panel. In case of that the particle size is under $1.0{\mu}m$, the particle deposition characteristic coefficient becomes larger as the electrostatic voltage induced to the cleanroom wall panel is increasing. Where in case of that the particle size is over $3.0{\mu}m$, the particle deposition characteristic coefficients do not show any differences with the electrostatic voltages. It is due to that the electrostatic force is the major particle transport mechanism for submicron particles, while the gravitational settling is the major particle transport mechanism for overmicron particles when the electro-static voltages are induced to the cleanroom wall panel.

• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.184-188
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• 2017

Polymer deposition pattern on the ceramic lid surface is analyzed by numerical modeling. Assumption was made that is affected by gas flow pattern from the horizontal and vertical nozzles, temperature profile from the finger-like branches made of graphite and electrostatic potential effect. Calculated results showed gas flow dynamics is less relevant than two others. Temperature and electrostatic effects are likely determining the polymer deposition pattern based on our numerical simulation results.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.10
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• pp.1284-1293
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• 1997

The electrostatic effect on particle deposition onto a heated, Horizontal free-standing wafer surface was investigated numerically. The deposition mechanisms considered were convection, Brownian and turbulent diffusion, sedimentation, thermophoresis and electrostatic force. The electric charge on particle needed to calculate the electrostatic migration velocity induced by the local electric field was assumed to be the Boltzmann equilibrium charge. The electrostatic forces acted upon the particle included the Coulombic, image, dielectrophoretic and dipole-dipole forces based on the assumption that the particle and wafer surface are conducting. The electric potential distribution needed to calculate the local electric field around the wafer was calculated from the Laplace equation. The averaged and local deposition velocities were obtained for a temperature difference of 0-10 K and an applied voltage of 0-1000 v.The numerical results were then compared with those of the present suggested approximate model and the available experimental data. The comparison showed relatively good agreement between them.

• Particle and aerosol research
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• v.5 no.1
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• pp.17-27
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• 2009

Particle deposition on a semiconductor wafer larger than 100 mm was studied experimentally and numerically. Particularly the electrostatic effect on particle deposition velocity was investigated. The experimental apparatus consisted of a particle generation system, a particle deposition chamber and a wafer surface scanner. Experimental data of particle deposition velocity were obtained for a semiconductor wafer of 200 mm diameter with the applied voltage of 5,000 V and PSL particles of the sizes between 83 and 495 nm. The experimental data of particle deposition velocity were compared with the present numerical results and the existing experimental data for a 100 mm wafer by Ye et al. (1991) and Opiolka et al. (1994). The present numerical method took into consideration the particle transport mechanisms of convection, Brownian diffusion, gravitational settling and electrostatic attraction in an Eulerian frame of reference. Based on the comparison of the present experimental and numerical results with the existing experimental results the present experimental method for a 200 mm semiconductor wafer was found to be able to present reasonable data.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.12
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• pp.573-578
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• 2003

In this study, new type of induction charging system for electrostatic spraying was manufactured and proposed to improve the electrical safety and charging efficiency. And parameters of proposed system to generate the maximum deposition current with electrical safety were selected and investigated. The selected parameters were frequency of square pulse and thickness of insulation material, outer diameter of device and thickness and positions of electrode. Charging quantity of water drop was measured by deposition current detected from sensing plate indirectly. The maximum deposition current for each parameter were 3.5[uA] at the frequency of 15[kHz] and thickness of 0.25[mm] insulating layer. And maximum deposition currents were 2.8[uA] and 3.0[uA] at 25[mm] outer diameter of charging device and 0.25[mm] thickness of electrode each. Effects of electrode position from spraying nozzle on deposition current was a little.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.779-785
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• 2006

Particle transport and deposition characteristics on semiconductor wafers inside the chamber were experimentally investigated via a particle generation & deposition system and a wafer surface scanner. Especially the relation between particle size($0.083{\sim}0.495{\mu}m$) and particle deposition velocity with ESA(Electrostatic Attraction) effect was studied. Spot deposition technique with the deposition system using nozzle type outlets of the chamber was newly conducted to derive particle deposition velocity and all experiment results were compared with the previous study and were in a good agreement as well.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.6
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• pp.641-652
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• 2000

The effect of block arrangement has been investigated on the particle deposition in the specified collecting cell of two-stage electrostatic precipitator by numerical analysis. Recirculation zone existed at the downstream of the block in the collecting cell, and the particles entering the recirculation zone were deposited on the collecting plate. Particle trajectory and deposition had considerably different phenomenon according to electrostatic and inertial effect, which depended on inlet mean velocity, electrostatic number, and particle diameter in the collecting cell. The total collection efficiency reached a minimum value through an interaction of electrostatic and inertial effect. In the computational domain, total collection efficiency for the case of two blocks in the computational domain was more than that of one block at the relative small electrostatic number. However as the block distance and inertial effect increased, the difference between the collection efficiency of two cases decreased. In the range of relatively small particle size total collection efficiency was always superior to particle collection efficiency that was predicted by Deutsch equation.

• Applied Chemistry for Engineering
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• v.19 no.1
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• pp.117-121
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• 2008

In this study, thin YSZ film was prepared by electrostatic spray deposition. The morphology of thin film was strongly influenced by precursor solution and substrate temperature. Especially, dense YSZ film was obtained at the substrate temperature of $400^{\circ}C$. The YSZ film growth rate was $12{\mu}m/h $ at the optimum conditions. Product film was characterized by XRD, FE-SEM and EDX.