• Particle and aerosol research
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• v.6 no.1
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• pp.21-27
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• 2010

New process consisting of electrospray and epitaxial crystal growth processes was applied to the preparation of c-plane oriented barium ferrite ($BaFe_{12}O_{19}$) thin film for high density magnetic recording media. Sodium citrate aided process was proper to preparation of amorphous $BaFe_{12}O_{19}$ nanoparticles with geometric mean diameter of 3 nm and geometric standard deviation of 1.1. The electrospray was applicable to the prepare of amorphous $BaFe_{12}O_{19}$ thin film on a substrate, and the film thickness could be controlled by adjusting the electrospray deposition time. The c-plane oriented $BaFe_{12}O_{19}$ thin film was successfully prepared by 3 step annealing process of the $BaFe_{12}O_{19}$ amorphous film on a sapphire($Al_2O_3$) substrate; annealing at $350^{\circ}C$ for 30 min, annealing at $500^{\circ}C$ for 30 min, and annealing at $700^{\circ}C$ for 60 min.

• Journal of the Korean GEO-environmental Society
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• v.11 no.1
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• pp.5-11
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• 2010

The objective of this study is to evaluate the effect of operational parameters such as rotation speed and vibrating milling time for the fabrication of photocatalytic $TiO_2$ thin film using aerosol deposition methods. $TiO_2$ powders produced in the range of 1,000-3,000 rpm of rotation speed of centrifugal separator are ineffective on the fabrication of $TiO_2$ thin film by aerosol deposition due to the problem of nozzle powder jam. $TiO_2$ powders controlled by vibrating milling had about 420 nm of average diameter after 2 hr of vibrating milling time. The result of XRD analysis indicated that $TiO_2$ powders had a anatase phase. Vibrating milling methods was considered to be an effective pre-treatment process for $TiO_2$ powder control. Consequently $TiO_2$ photocatalytic thin film with dispersion of anatase crystallites controled by vibrating milling was successfully fabricated by aerosol deposition. The permeation flux of $TiO_2$ photocatalytic thin film with the immobilized $TiO_2$ powder was higher than that of suspended $TiO_2$ powder. Therefore, $TiO_2$ photocatalytic thin film promises to be one of the effective methods for enhancing filtration performance for the treatment of organic pollutants.

• Journal of IKEEE
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• v.22 no.4
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• pp.1230-1233
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• 2018

$Al_2O_3$ films with the thickness of 50 nm were fabricated on 4H-SiC by aerosol deposition, and their electrical properties were characterized with different post annealing conditions. As a result, the $Al_2O_3$ film annealed in $N_2$ atmosphere showed decreased fixed charge density at the interface area between the $Al_2O_3$ and SiC, and increased leakage currents due to the generation of oxygen vacancies. From this result, it was confirmed that proper $N_2$ and $O_2$ ratio for the post annealing process is important.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.4
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• pp.271-277
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• 2010

$(Ba(Zr_{0.85}Y_{0.15})O_{3-\delta})$ oxide, showing high protonic conductivity at high temperatures and good chemical stability with $CO_2$ are referred to as hydrogen separation membrane. For high efficiency of hydrogen separation ($H_2$ flux and selectivity) and low fabrication cost, ultimate thin and dense BZY-Ni layer has to be coated on a porous substrate such as $ZrO_2$. Aerosol depostion (AD) process is a novel technique to grow ceramic film with high density and nano-crystal structure at room-temperature, and may be applicable to the fabrication process of AD integration ceramic layer effectively. XRD, SEM, X-ray mapping measurements were conducted in order to analyze the characteristics of BZY-Ni membrane fabricated by AD process. it is observed that it is homogeneous distribution for BZY-Ni. The result of $H_2$ permeation rate suggests that BZY-Ni composite is higher than BZY.

• Nuclear Engineering and Technology
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• v.29 no.4
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• pp.269-279
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• 1997

The errors associated with incorrect sampling and transport of radioactive aerosol from radwaste thermal process off-gas are analyzed and the conditions of representative sampling and correct transport of radioactive aerosol for off-gas system evaluation are discussed. An estimation method of sampling errors for individual radionuclides is proposed and applied to simulated vitrification melter aerosols. Prediction methods for particle deposition in sample transport tube under laminar as well as turbulent flow conditions are also described by example calculations with simulated incinerator off-gas From the results of example calculations and plots, instrumental and operational conditions of radioactive aerosol sampling system with minimized errors and correction methods for nonideal sampling and transport are recommended.

• Journal of Ocean Engineering and Technology
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• v.29 no.1
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• pp.94-99
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• 2015

Lead zirconate titanate (PZT) thick films with thicknesses of ㎛ were fabricated on silicon substrates using an aerosol deposition method. A PZT powder solution was prepared using a sol-gel process. The average diameters (d50) obtained were 1.67, 1.98, and 2.40μm when the pyrolysis temperatures were 300℃, 350℃, and 450℃ respectively. The as-deposited film had a uniform microstructure without any cracks or pores. The as-deposited films on silicon were annealed at a temperature of 700℃. The 20-㎛-thick PZT film showed good adherence between the PZT film and substrate, with no tearing observed in the conventional solid phase process. This was probably because the presence of pores produced from organic residue during annealing relieved the residual stresses in the deposited film.

• Particle and aerosol research
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• v.11 no.4
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• pp.93-98
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• 2015

Particles which generated from plasma enhanced chemical vapor deposition (PECVD) during thin film deposition process can affect to the process yield. By using light extinction method, ISPM can measure particles in the large-diameter pipe (${\leq}300mm$). In our research, in-situ particle monitor (ISPM) sensor was installed at the 300 mm diameter exhaust-line to count the particles in each size. In-house flange for mounting the transmitting and receiving parts of ISPM was carefully designed and installed at a certain point of exhaust line where no plasma light affect to the light extinction measurement. Measurement results of trend changes on particle count in each size can confirm that ISPM is suitable for real-time monitoring of vacuum process.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.5
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• pp.183-188
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• 2020

Lead zinc niobate (PZN)-added lead zirconate titanate (PZT) thick films with thickness of 5~10 ㎛ were fabricated on silicon and sapphire substrates using aerosol deposition method. The contents of PZN were varied from 0 %, 20 % and to 40 %. The PZN-added PZT film showed poorer electrical properties than pure PZT film when the films were coated on silicon substrate and annealed at 700℃. On the other hand, the PZN-added PZT film showed higher remanent polarization and dielectric constant values than pure PZT film when the films were coated on sapphire and annealed at 900℃. The ferroelectric and dielectric characteristics of 20 % PZN-added PZT films annealed at 900℃ were compared with the result values obtained from bulk ceramic specimen with same composition sintered at 1200℃. As annealing temperature increased, dielectric constant increased. These came from enhanced crystallization and grain growth by post heat treatment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.1
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• pp.14-20
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• 2018

Lead zinc niobate (PZN) added lead zirconate titanate (PZT) thick films with thickness of $5{\sim}10{\mu}m$ were fabricated on silicon and sapphire substrates using aerosol deposition method. The contents of PZN were varied from 0 %, 20 % and 40 %. The initial particles (PZT, 2PZN-8PZT, 4PZN-6PZT) had irregular shape and submicron sizes. The as-deposited film had fairly dense microstructure without any crack, and showed only a perovskite single phase formed with nano-sized grains. The as-deposited films on silicon were annealed at the temperatures of $700^{\circ}C$, and the films deposited on sapphire were annealed at $900^{\circ}C$ in the electrical furnace. The effects of PZN addition on the microstructural evolution were observed using by FE-SEM and HR-TEM.

• Journal of IKEEE
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• v.21 no.4
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• pp.404-407
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• 2017

We investigated the microstructure, electrical and optical characteristics of ZnO, AZO and ITO films using aerosol deposition process. As gas consumption increased, the electrical and optical characteristics of ZnO, AZO and ITO films were improved, and electrical and optical characteristics of ZnO, AZO and ITO films with a thickness of 400 nm were successfully fabricated on PET substrates at room temperature. The mechanical flexibility durability test shows that the ZnO films can withstand 5,000 cycles and AZO and ITO films occurs to crack in films with degradation of resistance and transmittance. Even though the AZO and ITO films shows slightly lower durability than the ZnO films, this is expected to improve performance of films through optimized processing condition and particle size control.