• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.5
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• pp.55-59
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• 2011

Atmospheric plasma technology was utilized in order to modify surface characteristics of base paper for coating. Argon(Ar) and oxygen(O2) gases were used. It was found that contact angle of a water droplet was decreased with increasing voltage during plasma treatment, meaning that the hydrophilicity of paper surface was increased. On the other hand, the physical properties like roughness and optical properties such as gloss, brightness and opacity were not influenced by the plasma treatment. In conclusion, atmospheric plasma technology can be utilized to control hydrophilicity of paper surface without affecting physical properties of the paper.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.184-187
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• 2002

Blood products from slaughterhouses that are not hygienically prepared for disposal or food consumption pose a human health hazard. Gamma irradiation is an effective method for sterilization of blood products, but may introduce changes in the molecular characteristics of proteins. This study evaluated the effects of irradiation on animal plasma proteins. Bovine and porcine blood was obtained from a slaughterhouse and the plasma proteins purified and lyophilized. The secondary structure and molecular weight distribution of the plasma protein solutions and powders were examined after ${\gamma}$-irradiation at 1, 5, 7 and 10 kGy. Gamma-irradiation affected the molecular properties of the protein solutions, but not the protein powders. Circular dichroism and sodium dodecyl sulfate-polyacrylamide gel electrophoresis studies showed that increased doses of ${\gamma}$-irradiation decrease the ordered structure of plasma proteins in solution, and cause initial fragmentation of the polypeptide chains and subsequent aggregation.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.33-35
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• 2016

In this study, a new plasma source was used in the ALD process. Line type plasma sources were analyzed by electric and magnetic field simulation. And the results were compared with plasma density and electron temperature measurement results. As a result, the results of the computer simulation and the diagnosis results of plasma density and electron temperature showed similar tendency. At this time, the plasma uniformity is 95.6 %. $Al_2O_3$ thin film was coated on 6 inch Si-wafer, using this plasma source. The uniformity of the thin film was more than 98% and the thin film growth rate was 0.13 nm/cycle.

• Journal of Adhesion and Interface
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• v.6 no.4
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• pp.7-11
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• 2005

Multi-walled carbon nanotubes (CNTs), which were purified by etching in 25% $H_2SO_4/HNO_3$ solution at $60^{\circ}C$ for 2 h, were modified via plasma polymerization coating of acrylic acid, allylamine or acetylene, and then utilized to prepare PEI/CNT composites. First, plasma polymerization conditions were optimized by measuring the solvent resistance of coatings in THF, chloroform and NMP, and the tensile strength of PEI/CNT (0.5%) composites as a function of plasma power (20~50 W) and monomer pressure (20~50 mTorr). The tensile strength of PEI/CNT composites was further evaluated as a function of CNT loading (0.2, 0.5 and 1%). Finally, FT-IR was utilized to provide a better understanding of the improved tensile properties of PEI/CNT composites via plasma polymerization coating of CNTs. Plasma polymerization of acrylic acid greatly enhanced the tensile strength of PEI/CNT composites, as did allylamine but to a lesser degree, while acetylene plasma polymerization coating decreased tensile strength.

• Composites Research
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• v.26 no.3
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• pp.165-169
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• 2013

This work presents the tensile properties and water uptake behavior of plasma treated abaca fibers reinforced epoxy composites. The composites were prepared by vacuum assisted resin transfer molding. The effects of treatment on tensile properties and sorption characteristics of abaca fiber composites in distilled water and salt solution at room temperature were investigated. The tensile strength of the composites increased with plasma treatment. With plasma treatment, an improvement of 92.9% was obtained in 2.5 min exposure time in plasma. This is attributed to high fiber-matrix compatibility. Less improvement on tensile properties of hybrid treatment of sodium hydroxide and plasma was obtained. However, both treatments reduced overall water uptake in distilled water and salt solution. Hydrophilicity of the fibers decreased upon plasma and sodium hydroxide treatment, which decreases water uptake.

• Journal of the Semiconductor & Display Technology
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• v.4 no.2 s.11
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• pp.11-14
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• 2005

In plasma processing reactors, it is common practice to control plasma density and ion bombardment energy by manipulating excitation voltage and frequency. In this paper, a dually excited capacitively coupled rf plasma reactor is self-consistently simulated with a three moment model. Effects of phase differences between primary and secondary voltage waves, simultaneously modulated at various combinations of commensurate frequencies, on plasma properties are investigated. The simulation results show that plasma potential and density as well as primary self-dc bias are nearly unaffected by the phase lag between the primary and the secondary voltage waves. The results also show that, with the secondary frequency substantially lower than the primary frequency, secondary self·do bias remains constant regardless of the phase lag. As the secondary frequency approaches to the primary frequency, however, the secondary self-dc bias becomes greatly altered by the phase lag, and so does the ion bombardment energy at the secondary electrode. These results demonstrate that ion bombardment energy can be more carefully controlled through plasma simulation.

• Journal of the Semiconductor & Display Technology
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• v.1 no.1
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• pp.35-40
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• 2002

Understanding of charging properties of a small particle is necessary to control the particle contamination and to improve productivity of the electronic device in the plasma aided semiconductor manufacturing processes. In this study, the effects of both magnetic field and particle size on the charging properties are experimentally investigated in collisional dusty plasmas. The experiments carried out in the system consisted of a monodisperse particle generation system, a DC magnetized plasma generation system and a charge measurement system. The plasma chamber is made of cross-shape Pyrex surrounded by magnetic bucket (composed of 12 permanent magnetic bar) to confine the plasma. DC magnetic field up to 250G are applied to the plasma zone by external magnetic coil. Previous work shows the charging effect clearly increase with increasing the size of the particle and plasma density, as it was expected.

• Food Science and Preservation
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• v.23 no.7
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• pp.960-966
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• 2016

This study was conducted to explore the potential for use of atmospheric pressure dielectric barrier discharge plasma (atmospheric pressure DBD plasma) as a non-thermal sterilization technology for microorganisms in dried red pepper. The effects of key parameters such as power, exposure time and distance on the sterilization efficiency and the quality of red dried pepper by the atmospheric pressure DBD plasma treatment were investigated. The results revealed that the plasma treatment was very effective for sterilization of Staphylococcus aureus, with 15 min of treatment at 1.0 kW and 20 mm sterilizing 82.6% of the S. aureus. Increasing the power or exposure time and decreasing the exposure distance led to improved sterilization efficiency. The atmospheric pressure DBD plasma treatment showed no effect on the ASTA (American spice trade association) value or hardness of dried red pepper. Furthermore, no effects of atmospheric pressure DBD plasma treatment were observed on the sensory properties of dried red pepper. To assess the storage stability, the dried red pepper was treated with atmospheric pressure DBD plasma (1.5 kW power, 15 min exposure time and 10 mm exposure distance), then stored for 12 weeks at $25^{\circ}C$. Consequently, the ASTA value, hardness and capsaicin concentration of dried red pepper were maintained.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.180-180
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• 2000

Plasma source ion implantation is a new doping technique for the formation of shallow junction with the merits of high dose rate, low-cost and minimal wafer charging damage. In plasma source ion implantation process, the wafer is placed directly in the plasma of the appropriate dopant ions. Negative pulse bias is applied to the wafer, causing the dopant ions to be accelerated toward the wafer and implanted below the surface. In this work, inductively couples plasma was generated by anodized Al antenna that was located inside the vacuum chamber. The outside wall of Al chamber was surrounded by Nd-Fe-B permanent magnets to confine the plasma and to enhance the uniformity. Before implantation, the wafer was pre-sputtered using DC bias of 300B in Ar plasma in order to eliminate the native oxide. After cleaning, B2H6 (5%)/H2 plasma and negative pulse bias of -1kV to 5 kV were used to form shallow p+/n junction at the boron dose of 1$\times$1015 to 5$\times$1016 #/cm2. The as-implanted samples were annealed at 90$0^{\circ}C$, 95$0^{\circ}C$ and 100$0^{\circ}C$during various annealing time with rapid thermal process. After annealing, the sheet resistance and the junction depth were measured with four point probe and secondary ion mass spectroscopy, respectively. The doping uniformity was also investigated. In addition, the electrical characteristics were measured for Schottky diode with a current-voltage meter.

• Journal of the Microelectronics and Packaging Society
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• v.22 no.3
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• pp.31-38
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• 2015

In order to achieve a high speed and high quality silicon wafer bonding, the room-temperature direct bonding using atmospheric pressure plasma and sprayed water vapor was developed. Effects of different plasma fabrication parameters, such as flow rate of $N_2$ gas, flow rate of CDA (clear dry air), gap between the plasma head and wafer surface, and plasma applied voltage, on plasma activation were investigated using the measurements of the contact angle. Influences of the annealing temperature and the annealing time on bonding strength were also investigated. The bonding strength of the bonded wafers was measured using a crack opening method. The optimized condition for the highest bonding strength was an annealing temperature of $400^{\circ}C$ and an annealing time of 2 hours. For the plasma activation conditions, the highest bonding strength was achieved at the plasma scan speed of 30 mm/sec and the number of plasma treatment of 4 times. After optimization of the plasma activation conditions and annealing conditions, the direct bonding of the silicon wafers was performed. The infrared transmission image and the cross sectional image of bonded interface indicated that there is no void and defects on the bonded wafers. The bonded wafer exhibited a bonding strength of average $2.3J/m^2$.