• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.157-158
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• 2002

A surface hardenable low alloy carbon steel was implanted with medium energy (20 - 50KeV) $N_2^+$ ions to produced a modified hardened surface. The implantation conditions were varied and are given in several doses. The surface hardness of treated and untreated steels were measured using depth sensing ultra micro indentation system (UMIS). It is shown that the hardness of nitrogen ion implanted steels varied from 20 to 50GPa depending on the implantation conditions and the doses of implantation. The structure of the modified surfaces was examined by X-ray photoelectron spectroscopy (XPS). It was found that the high hardness on the implanted surfaces was as a result of formation of non-equilibrium nitrides. High-resolution XPS studies indicated that the nitride formers were essentially C and Si from the alloy steel. The result suggests that the ion implantation provided the conditions for a preferential formation of C and Si nitrides. The combination of evidences from nano-indentation and XPS, provided a strong evidence for the existence of $sp^3$ type of bonding in a suspected $(C,Si)_xN_y$ stoichiometry. The formation of ultra hard surface from relatively cheap low alloy steel has significant implication for wear resistance implanted low alloy steels.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.34-39
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• 2022

The ion implantation technology changes the chemical state of the surface of a material by implanting ions on the surface. It improves the wear resistance, friction characteristics, etc. Plasma ion implantation can effectively reinforce a surface by implanting a sufficient amount of plasma nitrogen ions and using the injection depth instead of an ion beam. As plasma ion implantation is a three-dimensional process, it can be applied even when the surface area is large and the surface shape is complicated. Furthermore, it is less expensive than competing PVD and CVD technologies. and the material is The accommodation range for the shape and size of the plasma is extremely large. In this study, we improved wear resistance by implanting plasma nitrogen ions into a carbide end mill tool, which is frequently used in high-speed machining

• Journal of the Korean Magnetics Society
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• v.8 no.1
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• pp.6-12
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• 1998

Fe-N(iron-nitrogen) crystal phases were prepared by nitrogen ion implantation into $\alpha$-Fe foil with Plasma Source Ion Implantation (PSII). Ion implantation time of sample is treated 15 minutes(FeN15) and 30 minutes (FeN30). The nitrogen depth profiles measured by Auger electron spectroscopy (AES) were determined to be about 12000 $\AA$ and 4000 $\AA$ for the samples of FeN15 and FeN30, respectively. The results of vibrating sample magnetometer (VSM) show that the saturation magnetization of the samples of as-implanted FeN15 and FeN30 was higher than that of pure $\alpha$-Fe foil, which may be owing to $\alpha$'-$Fe_8N$ or $\alpha$"-$Fe_{16}N_2$ phases. Accordingly this study shows the possibility of the partial formation of $\alpha$' or $\alpha$" phase in iron nitrogen produced by PSII method.II method.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.1
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• pp.106-113
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• 2010

The most suitable condition for plasma source ion implantation(PSII) was found based on the study of the characteristics of PSIIed tool and machined surfaces. The depth analysis according to the chemical bonding state of elements and surface component elements through the XPS and SIMS, was conducted to find the improved property of the PSIIed surface. Due to the diffusion of PSII, the nitrogen was found up to a depth of about 150nm according to the supplied voltage and ion implanted time. The deep diffusion by nitrogen caused the surface modification, but the formation of oxide component was found due to the residual gas contamination on the surface. Statistical method of ANOVA was conducted to find the effects of spindle speed and feed rate in interaction for machined surface roughness with PSIIed tools. The surface modification was found largely occurred by the nitrogen implanted surface with 2 hours for 27kV, 35kV and 43kV.

• Tribology and Lubricants
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• v.23 no.1
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• pp.14-18
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• 2007

SCM415 alloy was implanted with nitrogen ions using plasma source ion implantation (PSII), at a dose range of $1{\times}10^{17}\;to\;6{\times}10^{17}N^{+}cm^{-2}$. Auger electron spectrometry (AES) was used to investigate the depth profile of the implanted layer. Friction and wear tests were carried out on a block-on-ring wear tester. Scanning electron microscopy (SEM) was used to observe the micro-morphology of the worn surface. The results revealed that after being implanted with nitrogen ions, the frictional coefficient of the surface layer decreased, and the wear resistance increased with the nitrogen dose. The tribological mechanism was mainly adhesive, and the adhesive wear tended to become weaker oxidative wear with the increase in the nitrogen dose. The effects were mainly attributed to the formation of a hard nitride precipitate and a supersaturated solid solution of nitrogen in the surface layer.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.4
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• pp.712-718
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• 2003

The effects of nitrogen ion implantation on vacuum evaporated cadmium sulphide (CdS) thin films were investigated by X-ray diffraction, optical transmittance spectra, and Raman scattering studies. The as-deposited CdS films have a hexagonal structure with preferential (0 0 2) orientation. Formation of Cd metallic clusters was observed in ion implanted films from the XRD patterns. The band gap of N+ implanted films decreased, whereas the optical absorption coefficient values increased with the increase of implantation dose. The Raman peak position appeared at 299 cm-1 and the FWHM increased with the ion dose. A decrease in the area of Raman peak of CdS Al(LO) mode is seen on implantation.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.181-181
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• 2009

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.86-86
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• 2000

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.6
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• pp.471-478
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• 2002

Vacuum evaporated cadmium sulphide (CdS) thin films were implanted with $Ar^+$ and $N^+$ for different doses. The properties of the ion implanted CdS thin films have been analysed using XRD, optical transmittance spectra, and Raman scattering studies. Formation of Cd metallic clusters were observed in ion implanted films. The band gap of $Ar^+$ doped films decreased from 2.385 eV of the undoped film to 2.28 eV for the maximum doping. In the case of $N^+$ doped film the band gap decreased from 2.385 to 2.301 eV, whereas the absorption coefficient values increased with the increase of implantation dose. On implantation of both types of ions, the Raman peak position appeared at $299\textrm{cm}^{-1}$ and the FWHM changed with the ion dose.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.206-211
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• 1992

SIMOX SOI structures were formed by oxygen ion implantation with a dose of 2 1018 ions/cm2 at 180kev and post-implantation annealing at $1250^{\circ}C$ for 6 hours in nitrogen ambient. The oxygen redistribution process during post-implantation annealing was examined by AES and TEM. The electrical property of the structure was investigated by SRP method. We could find oxygen precipitates in SOI layer was discussed. And the limiting factor to the decrease of the precipitates during post-implantation annealing was discussed also.