• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.57-61
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• 2006

The research on surface modification technology has been advanced to improve the properties of engineering materials. Ion implantation is a novel surface modification technology that enhances the mechanical, chemical and electrical properties of substrate's surface using accelerated ions. In this research, nitrogen ions were implanted into AC7A aluminum substrates which would be used as molds for rubber molding. The composition of nitrogenion implanted aluminum and distribution of nitrogen ions were analyzed by Auger Electron Spectroscopy (AES). To analyze the modified surface, properties such as hardness, friction coefficient, wear resistance, contact angle, and surface roughness were measured. Hardness of ion implanted specimen was higher than that of untreated specimen. Friction coefficient was reduced, and wear resistance was improved. From the experimental results, it can be expected that implantation of nitrogen ions enhances the mechanical properties of aluminum mold.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.6-6
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• 2009

We present an alternative process whereby deuterium is delivered to the location where the gate oxide reside by an implantation process. Deuterium ions were implanted using different energies to account for the topography of the overlaying layers and placing the D peak at the top of gate oxide. A short anneal at forming gas was performed to remove the D-implantation damage. We have observed that deuterium ion implantation into the gate oxide region can successfully remove the interface states and the bulk defects.

• 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.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.127-132
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• 1998

$Medpor^{(R)}$(porous polyethylene) Surgical Implants are used for the augmentation or restoration of bony contour in craniofacial defects. The purpose of this study is to evaluate the ingrowth of soft tissue and bone after application in calvaria of rats. The experiment was carried out in 60 rats. The reflected periosteum was resutured after implantation of $Medpor^{(R)}$ as a experimental site, while in the calvarial bone the reflected periosteum resutured without implantation as a control site. The histologic examination was performed after 1-, 2-, 4-, 8-, 12-, 24-weeks implantation in calvaria of rats. I concluded that there was abundant ingrowth of soft tissue and bone without any adverse tissue response and that it shows good stability.

• Imaging Science in Dentistry
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• v.35 no.3
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• pp.121-125
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• 2005

Purpose : The purpose of this study was to investigate whether the fractal dimension of successive panoramic radiographs of bone after implant placement is useful in the characterization of structural change in alveolar bone. Materials and Methods. Twelve subjects with thirty-five implants were retrospectively followed-up from one week to six months after implantation. Thirty-six panoramic radiographs from twelve patients were classified into 1 week, 1-2 months and 3-6 months after implantation and digitized. The windows of bone apical and mesial or distal to the implant were defined as periapical region of interest (ROI) and interdental ROI; the fractal dimension of the image was calculated. Results There was not a statistically significant difference in fractal dimensions during the period up to 6 months after implantation. The fractal dimensions were higher in 13 and 15mm than 10 and 11.5mm implant length at interdental ROIs in 3-6 months after implantation (P<0.01). Conclusion : Longer fixtures showed the higher fractal dimension of bone around implant. This investigation needs further exploration with large numbers of implants for longer follow-up periods.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.12 s.177
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• pp.124-130
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• 2005

The research on surface modification technology has been advanced to improve the properties of engineering materials. ion implantation is a novel surface modification technology to enhance the mechanical, chemical and electrical properties of substrate's surface using accelerated ions. In this research, nitrogen ions were implanted into aluminum substrates which would be used for mold of rubber materials. The composition of nitrogen ion implanted aluminum alloy and nitrogen ion distribution profile were analyzed by Auger Electron Spectroscopy (AES). To analyze the modified surface, properties such as hardness, friction coefficient, wear resistance, contact angle, and surface roughness were measured. Hardness of ion implanted specimens was higher than that of untreated specimens. Friction coefficient was reduced, and wear resistance was improved. From the experimental results, it can be expected that ion implantation of nitrogen enhances the surface properties of aluminum mold.

• Journal of the Korean Vacuum Society
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• v.8 no.2
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• pp.157-164
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• 1999

The post ion implantation has been applied to modify early-grown BN layer and improve the adhesion of the BN films. The effect of ion implantation doses on microstructure and interlayer was investigated by FTIR and HRTEM. And the hardness and delamination life time of N+-implanted BN films were measured. With increasing the ion dose up to $5.0\times10^{15}\textrm{atoms/cm}^2$,the change of IR spectrum is observed. At $5.0\times10^{16}\textrm{atoms/cm}^2$, a drastic transition of cubic phase into hexagonal phase is detected. The change of microstructure of early-grown layers by ion implantation is confirmed using HRTEM. Both microhardness and delamination life time of BN films increase with ion dose. The modification model of early-grown BN layers is briefly discussed based on the displacement per atom and excess boron in the BN film induced by ion irradiation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.4
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• pp.251-259
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• 2010

We proposed a tail function parameter extraction procedure for the establishment of a robust ion implantation database. We showed that, for the expression of ion implantation profiles, there are many local minimum values set for the third and fourth moment parameters of $\gamma$ and $\beta$ for the Pearson function that comprises the standard dual Pearson and tail functions. We proposed the use of a joined tail function as a mediate function to extract $\gamma$ and $\beta$, and demonstrated that this enables us to extract the parameters uniquely. Other parameters associated with channeling phenomena can also be simply and uniquely extracted by our procedure.

• Journal of Korean Neurosurgical Society
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• v.49 no.6
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• pp.323-328
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• 2011

Objective : Epidural fibrosis and adhesion are the main reasons for post-laminectomy sustained pain and functional disability. In this study, the authors investigate the effect of irradiated freeze-dried human amniotic membrane on reducing epidural adhesion after laminectomy on a rat model. Methods : A total of 20 rats were divided into two groups. The group A did not receive human amniotic membrane implantation after laminectomy and group B underwent human amniotic membrane implantation after laminectomy. Gross and microscopic findings were evaluated and compared at postoperative 1, 3 and 8 weeks. Results : The amount of scar tissue and tenacity were reduced grossly in group of rats with human amniotic membrane implantation (group B). On a microscopic evaluation, there were less inflammatory cell infiltration and fibroblast proliferation in group B. Conclusion : This experimental study shows that implantation of irradiated freeze-dried human amniotic membrane reduce epidural fibrosis and adhesion after spinal laminectomy in a rat model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.17-20
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• 2000

This study is about a retrograde triple well employed in the Cell tr. of next DRAM and flash memory. triple well structure is formed deep n-well under the light p-well using MeV ion implantation. MeV P implanted deep n-well was observed to show greatly improved characteristics of electrical isolation and soft error. Junction leakage current, however, showed a critical behavior as a function of implantation and annealing conditions. {311} defects were observed to be responsible for the leakage current. {311} defects were generated near the R$\sub$p/ (projected range) region and grown upward to the surface during annealing. This is study on the defect behavior in device region as a function of implantation and annealing conditions.