• Korean Journal of Metals and Materials
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• v.46 no.1
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• pp.39-43
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• 2008

PSII (Plasma Source Ion Implantation) using high density pulsed ICP source was employed to implant oxygen ions in Si wafer. The PSII technique can achieve a nominal oxygen dose of $3 {\times}10^{17}atoms/cm^2$ in implantation time of about 20min. In order to prevent oxidation of SOI layer during high temperature annealing, the wafer was capped with $2,000{\AA}$ $Si_3N_4 $ by PECVD. Cross-sectional TEM showed that continuous $500{\AA}$ thick buried oxide layer was formed with $300{\AA}$ thick top silicon layer in the sample. This study showed the possibility of SOI fabrication using the plasma source ion implantation with pulsed ICP source.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.134-139
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• 1999

In this study, PSII(plasma source ion implantation) was used to improve the biocompatibility of bone-anchored Ti implant. According to potentiodynamic anodic polarization test in deaerated Hank's solution, open circuit potential of ion implanted specimens were increased compare to that of unimplanted specimen ; besides, passive current density and critical anodic current density of ion implanted specimens were lower than unimplanted specimen.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.363-366
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• 2004

In order to obtain an industrial strain with higher L(+)-lactic acid yield, the wild type strain Rhizopus oryzae PW352 was mutated by means of Nitrogen ions implantation (l5 Kev, $7.8 \times 10^{14} - 2.08 \times 10^{15} ions/Cm^2$ and two mutants RE3303 and RF9052 were isolated. After 36 h shake-flask cultivation, the concentration of L(+)-lactic acid reached 131-136 g/l, the conversion rate of glucose was as high as 86%-90% and the productivity was 3.61 g/l.h. It was almost a 75% increase in lactic acid production compared with the wild type strain. Maximum fermentation temperature of RF9052 was increased to $45^{\circ}C$ from original $36^{\circ}C$. At the same time, the preferred range of fermentation temperature of RF9052 was broadened compared with PW352.

• Journal of the Korean Ceramic Society
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• v.36 no.8
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• pp.813-819
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• 1999

Inner crack-like pores with controlled amount of Ca impurity level in the high purity alumina single crystal sapphire had been created by micro-fabrication technique which includes ion implantation photo-lithography Ar ion milling and hot press technique. The morphological change and the healing of crack-like pore in the Ca doped high purity single crystal alumina during high temperature heat treatment in vacuum were observed using optical microscopy. The hexagonal bridging ligaments were developed and the size of hexagonal bridging ligaments had been increased with temperature and Ca amount and had grown to their corner rounded. It appeared that the hexagonal bridging ligaments would have an equilbrium size with temperature and the amount of Ca addition. Three kinds of crack-like pore healing type were observed. Edge regression and ligament growth were observed from relatively low temperature in the crack-like pore. Edge regression were found in almost all of the crack-like pore but the ligament growth were found only in the several crack-like pores accelerating heating very fast. Flow type healing was observed above $1800^{\circ}C$ and It healed the crack-like pore very slowly.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1069-1071
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• 1995

The electrical properties of Al/TiN/Ti contact are investigated at submicron contacts. The contact resistance and contact leakage current are dependent on metallization, surface dopant concentration, semiconductor surface treatment and contact plug ion implantation. In this paper, the contact resistance and contact leakage current are studied according to surface dopant concentration, semiconductor surface treatment and contact plug ion implantation at 0.8 micron contact. The contact resistance and contact leakage current increases with increasing substrate ion concentration. HF cleaning represents high contact resistance but low contact leakage current while CDE cleaning represents low contact resistance but high contact leakage current. Contact plug ion implantation decreases contact resistance but increases contact leakage current. Specially, RTA represents good electrical properties.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.755-760
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• 2012

In this study, three dimensional cutting force components and surface roughness appeared in high speed cutting by using tungsten carbide endmill tools implanted ion or not found mutual relations through several analysis of statistical dispersion. It is showed that cutting force(Fx) is affect with spindle speed and feed rate, cutting force(Fy) is affect with spindle speed and ion implantation time and cutting force(Fz) is affect with feed rate in interaction through the statistical method of ANOVA of cutting force and surface roughness, it is analyzed that it is affected of spindle speed and feed rate in surface roughness.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.956-960
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• 2004

Effects of ion implantation and deposition on the tribological properties of DLC film as a function of implanted energies and process times were investigated. TiC ions were implanted and deposited on the Si-wafer substrates followed by DLC coating using ion beam deposition method. In order to study tribological properties such as friction coefficient and behavior of DLC film on the modified surface as a function of implanted energies and process times, we used a ball-on-disc type apparatus in the atmospheric environment. From results of wear test, as the implanted energy was increased, the friction coefficient was more stable below 0.1.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.185-186
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• 2005

Intrinsic gettering is usually used to improve wafer quality which is an important factor for reliable ULSI devices. The two-step annealing method was adopted in order to investigate interactions between oxygens and secondary defects during oxygen precipitation process in lightly and heavily boron doped silicon wafers with high energy $^{11}B^+$ ion implantation. Secondary defects were inspected nearby the projected range by high resolution transmission electron microscopy. Oxygen pileup was measured in the vicinity of the projected range by secondary ion mass spectrometry for heavily boron doped silicon wafers.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.339-340
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.159-160
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• 2010