• 한국표면공학회지
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• 제29권6호
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• pp.781-787
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• 1996

Silicom oxide films with good water repellency were prepared by rf plasma-enhanced CVD (rf-PECVD) using four kinds of organosilicon compound, which had different number of methyl ($CH_3$) groups, and oxygen as gas sources. The differences in the deposition rates, film composition and film properties were studied in detail. Water repellency depended on the number of $CH_3$ groups in the organosilicon compounds and the partial pressure of oxygen in the plasma. The highest contact angle for water drops, about 95 degrees, was obtained when trimethy lmethoxy silane (TMMOS) was used. The contact angle decreased with the amount of oxygen gas introduced into the plasma. The dissociation of $CH_3$ groups by adding oxygen was comfirmed by Fourier transform infrared spectroscopy(FTIR) and X-ray photoelectron spectroscopy (XPS). The optical properties were estimated by double-beam spectroscopy and ellipsometry. The transmittance of the glass plate coated by the film prepared with tetramethoxy silane (TMOS) was about 90% and the refractive index of film was 1.44. This value was smaller than the refractive index of a glass plate(soda lime glass, refractive index is 1.515) and this film played a role of anti-refractive coating.

• 한국전기전자재료학회논문지
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• 제23권1호
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• pp.10-13
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• 2010

The plasma processing technologies of thin film deposition and surface treatment technique have been applied to many industrial fields. This study is purposed Large-area uniformity and surface treatment on the stainless substrate. We treat surface of stainless by $CF_4$ plasma. $CF_4$ plasma is generated by using SPM(Scanning plasma method)which is kind a of CVD. Generally, SPM has been used for uniform surface treatment using a crossed electromagnetic field. The optimum discharge condition has been studied for the gas pressure, the magnetic flux density and the distance between substrate and electrodes. In result, contact angle is increased by surface treatment using $CF_4$ Plasma. Therefore we expect that SPM to control contact angle is applied to many industries.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.276-279
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• 2004

Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.185.2-185.2
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• 2016

The plasma density is an essential plasma parameter describing plasma physics. Furthermore, it affects the throughput and uniformity of plasma processing (etching, deposition, ashing, etc). Therefore, a novel technique for plasma density measurement has been attracting considerable attention. Microwave probe is a promising diagnostic technique. Various type of cutoff, hairpin, impedance, transmission, and absorption probes have been developed and investigated. Recently, based on the basic type of probes, modified flat probe (curling and multipole probes), have been developing for in situ processing plasma monitoring. There is a need for comparative study between the probes. It can give some hints on choosing the reliable probe and application of the probes. In this presentation, we make attempt of numerical study of different kinds of microwave probes. Characteristics of frequency spectrum from probes were analyzed by using three-dimensional electromagnetic simulation. The plasma density, obtained from the spectrum, was compared with simulation input plasma density. The different microwave probe behavior with changes of plasma density, sheath and pressure were found. To confirm the result experimentally, we performed the comparative experiment between cutoff and hairpin probes. The sheath and collision effects are corrected for each probe. The results were reasonably interpreted based on the above simulation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.611-615
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• 2003

In this paper, a operation characteristics and analysis of the HB(half bridge) inverter for remote plasma system are studied. the remote plasma system is cleaning system for the chemical vapor deposition (CVD) chamber in semiconductor processing. The remote plasma system is powered by the RF generator The main power stage of the RF generator is used for the HB PWM inverter with an low pass filter in the secondary circuit of the transformer. The detailed mode analysis of HB invertor was described. The operation characteristics of Remote Plasma Source are verified by simulation and experimental results.

• Journal of Advanced Marine Engineering and Technology
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• 제39권8호
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• pp.833-837
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• 2015

Li-air batteries have a promising future for because of their high energy density, which could theoretically be equal to that of gasoline. However, substantial Li-air cell performance limitations exist, which are related to the air cathode. The cell discharge products are deposited on the surfaces of the porous carbon materials in the air electrode, which blocks oxygen from diffusing to the reaction sites. Hence, the real capacity of a Li-air battery is determined by the carbon air electrode, especially by the pore volume available for the deposition of the discharged products. In this study, a simple and fast method is reported for the large-scale synthesis of carbon nanoballs (CNBs) consisting of a highly mesoporous structure for Li-air battery cathodes. The CNBs were synthesized by the solution plasma process from benzene solution, without the need for a graphite electrode for carbon growth. The CNBs so formed were then annealed to improve their electrical conductivity. Structural characterization revealed that the CNBs exhibited both an pore structure and high conductivity.

• 열처리공학회지
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• 제22권4호
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• pp.223-227
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• 2009

The feasibility of plasma electrolytic polishing technology of stainless steel was examined. The results show that austenitic stainless steel can be polished clearly using potentiostatic regimes with various concentration of ammonium sulfate ($(NH_4)_2SO_4$) solution above certain initial temperature. The equipment and deposition produces for polishing process are described and the effect of processing parameters on the characterizations polished-samples has been investigated.

• 한국표면공학회지
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• 제29권5호
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• pp.519-524
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• 1996

We synthesized semiconducting Sn-doped diamondlike carbon films by rf plasma-enhanced chemical vapor deposition using an organotin compound as a dopung gas source. XPS quan-titative analysis for the deposited films after 60 s argon ion etching revealed that Sn concen-tration increased with the partial pressure of the organotin compound in the reactant gas. In C 1s spectra, there was a component due to C-Su bond which had a negative chemical shift. C 1s spectra also indicated that the deposited films were relatively $sp^2$ rich. The chemical shift of the Sn-C bond in Sn $3d_{5/2}$ spectra was about +1.7 eV. The electrical resistivity and the optical transmittance were also investigated.

• Journal of Ceramic Processing Research
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• 제20권6호
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• pp.589-596
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• 2019

Pigments with minute particle sizes, such as carbon black (CB) and pigment red 48:2 (P.R.48:2), are the most important types of pigment and have been widely used in many industrial applications. However, minute particles have large surface areas, high oil absorption and low surface energy. They therefore tend to be repellent to the vehicle and lose stability, resulting in significant increases in viscosity or reaggregation in the vehicle. Therefore, finding the best way to improve the dispersion properties of minute particle size pigments presents a major technical challenge. In this study, minute particle types of CB and P.R.48:2 were treated with nitrogen gas plasma generated via radio frequency-plasma enhanced chemical vapor deposition (RF-PECVD) to increase the dispersion properties of minute particles in deionized (DI) water. The morphologies and particle sizes of untreated and plasma treated particles were evaluated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The average distributions of particle size were measured using a laser particle sizer. Fourier transform infrared spectroscopy was carried out on the samples to identify changes in molecular interactions during plasma processing. The results of our analysis indicate that N2 plasma treatment is an effective method for improving the dispersibility of minute particles of pigment in DI water.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권8호
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• pp.401-408
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• 2001

The information of the ion composition in plasma applications is required to characterize a plasma. A better understanding of ion species composition ratio and its spacial distribution, etc. is thus necessary in plasma-related processes, such as thin film deposition, plasma-based ion implantation, semiconductor processing, and so on. In this research, a compact ion mass analyzer that is based on magnetic sector analyzer was developed and its operational characteristics were studied in nitrogen plasma.