• Korean Journal of Materials Research
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• v.25 no.6
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• pp.293-299
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• 2015

In this study, nitrogen ions were implanted into STS 316L austenitic stainless steel by plasma immersion ion implantation (PIII) to improve the corrosion resistance. The implantation of nitrogen ions was performed with bias voltages of -5, -10, -15, and -20 kV. The implantation time was 240 min and the implantation temperature was kept at room temperature. With nitrogen implantation, the corrosion resistance of 316 L improved in comparison with that of the bare steel. The effects of nitrogen ion implantation on the electrochemical corrosion behavior of the specimen were investigated by the potentiodynamic polarization test, which was conducted in a 0.5 M $H_2SO_4$ solution at $70^{\circ}C$. The phase evolution and texture caused by the nitrogen ion implantation were analyzed by an X-ray diffractometer. It was demonstrated that the samples implanted at lower bias voltages, i.e., 5 kV and 10 kV, showed an expanded austenite phase, ${\gamma}_N$, and strong (111) texture morphology. Those samples exhibited a better corrosion resistance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.131-131
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• 2008

Silicon carbide (SiC) has attracted significant attention for high frequency, high temperature and high power devices due to its superior properties such as the large band gap, high breakdown electric field, high saturation velocity and high thermal conductivity. We performed Al ion implantation processes on n-type 4H-SiC substrate using a SILVACO ATHENA numerical simulator. The ion implantation model used a Monte-Carlo method. We studied the effect of channeling by Al implantation simulation in both 0 off-axis and 8 off-axis n-type 4H-SiC substrate. We have investigated the Al distribution in 4H-SiC through the variation of the implantation energies and the corresponding ratio of the doses. The implantation energies controlled 40, 60, 80, 100 and 120 keV and the implantation doses varied from $2\times10^{14}$ to $1\times10^{15}cm^{-2}$. In the simulation results, the Al ion distribution was deeper as increasing implantation energy and the doping level increased as increasing implantation doses. After the post-implantation annealing, the electrical properties of Al-implanted p-n junction diode were investigated by SILV ACO ATLAS numerical simulator.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.946-949
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• 1999

In this research we have developed a reliable, effective and feasible HEI(High-Energy Ion Implantation) process 3D-simulation tool, and then by using it we can predict and analyze the effect of HEI process on characteristics of the standard CMOS device. high-energy ion implantation above 200 keV is inevitable process to form retrograde well and buried layer to prevent leakage current, to conduct field implant for field isolation, and to perform after-gate implantation. The feasible analysis tool is a product of the HEI process modeling verified by comparison of the SIMS experiments with the simulation results. Especially, in this paper, we present the predicting capability of HEI-induced impurity and damage profiles compared with the published SIMS data in order to acquire the reliability of our results ranging from few keV to several MeV for phosphorus and boron implantation.

• The Journal of the Korean dental association
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• v.55 no.10
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• pp.716-724
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• 2017

Past literatures stressed that when a gap occurred between smooth surface implant and alveolar bone, osseointegration was unsatisfactory at histologic examination regardless of clinical findings. Accordingly, standard surgical approach in the early days of implant surgery was to place the implant after all gap was healed. However, Botticelli et al.(2004) reported high degree of osseointegration at the gap with SLA surface implant. From then, the era of immediate implantation has begun because SLA surface implant make gap healing possible. There are two main disadvantages of immediate implantation: (1) surgical technique is sensitive for primary implant stability, (2) Implant placement at the accurate position that predicts external change of extraction wound is required. Immediate implantation has outstanding advantages in all perspectives except for the above-mentioned disadvantages. Therefore, it would be unwise to abandon the option of immediate implantation simply due to surgical difficulties. The purpose of this paper is to describe the necessity of immediate implantation and to present scientific evidence for immediate implantation and accurate implant position by literature review.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.7
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• pp.382-386
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• 2004

A study has been made of surface modification of organic materials by ion implantation to increase the surface electrical properties. The substrate used were PET(polyethylene teraphtalate). N$^{＋}$, Ar$^{＋}$ implantation was peformed at energies of 40 keV and 50 keV with fluences from $5{\times}10^{15}$, $1{\times}10^{16}$,$7{\times}10^{16}$, $1{\times}10^{17}$/ ions/$cm^2$. UV/Vis, FT-IR and XPS spectroscopy measured for surface structure changes. Surface resistance decrease of implanted polymers was affected by ion implantation energy, ion species and ion dose rate. Surface conductivity of PET increased $2{\times}10^{9}$/∼$2{\times}10^{10}$/$\Omega$/sq by ion implantation. Result of various spectroscopy analysis, the cause of increasing PET surface conductivity was expected to breaking C=O bonds. It was formation carbon network structure by promote cross-linking and create C-C, C=C bonds.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.3
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• pp.175-180
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• 2003

As the integrated circuit device shrinks to the deep submicron regime, the ion implantation process with high ion dose has been attracted beyond the conventional ion implantation technology. In particular, for the case of boron ion implantation with low energy and high dose, the stabilization and throughput of semiconductor chip manufacturing are decreasing because of trouble due to the machine conditions and beam turning of ion implanter system. In this paper, we focused to the improved characteristics of processing conditions of ion implantation equipment through the modified deceleration mode. Thus, our modified recipe with low energy and high ion dose can be directly apply in the semiconductor manufacturing process without any degradation of stability and throughput.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.1
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• pp.43-49
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• 1987

In the present study, hormonal changes in uterine tissue and circulation were evaluated during the implantation period in rats in order to understand the mechanism by which implantation takes place. The results obtained were as follows. 1. Concentrations of serum estradiol and progesterone were significantly increased on days 4 and 5. 2. Concentration of estrogen receptor reached maximum on day 5 when implantation normally occurred in rats. On the other hand, progesterone receptor was gradually decreased, reaching the lowest on day 5. 3. Uterine PGs and cAMP concentrations were significantly increased on day 5. 4. Uterine PGs and cAMP concentrations in implant sites were significantly greater than those in non-implant sites. It is, therefore, concluded that prostaglandins and cAMP in uterine tissue as well as circulating ovarian steroid hormones were increased during the period of implantation, suggesting that these hormones might be actively involved in the process of implantation in rats.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.271-278
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• 1986

These studies were carried out to investigate the effects of the antiestrogens, LY-117018 and tamoxifen, on implantation in ovariectomized or intact adult rats. A Quantity of $80\;{\mu}g$ of LY-l17018 or tamoxifen was given to adult female rats on Day 1, 2, 3 and 4 of pregnancy and investigated the implantation sites on Bay 8 of pregnancy. The rats were ovariectomized at the first day of pregnancy and treated with various doses of LY-l17018 or tamoxifen together with progesterone daily from Day 2 to 8 of pregnancy and then investigated the implantation sites on Day 8 of pregnancy The results were summarized as follows; When a single dose of $80\;{\mu}g$ LY-l17018 and tamoxifen was given during the first 4 days of pregnancy, the implantation was intesively inhibited in the pregnant rat treated with LY-l17018 on Day 2 $(14.4{\pm}3.5%),\;3(16.3{\pm}5.3%)\;and\;tamoxifen\;on\;Days\;2\;(17.4{\pm}4.6%),\;3\;(16.3{\pm}2.8%)\;and\;4\;(13.9{\pm}3.5%).$ LY-l17018 was apt to inhibit more potently the implantation than tamoxifen except on Day 4 of pregnancy In rats ovariectomized on Day 1 of pregnancy and treated continucusly with 12? r9 of LY-117018 and tamoxifen together with progesterone showed the highest implantation rate, compared with the rats treated continuously with different doses of the two drugs. The correlation coefficients between the dosage of drugs and implantation rate were r= 0.91 (LY-117018), 0.51 (tamoxifen), respectively, except treatment with $625\;{\mu}g$ of the drugs. Tamoxifen was apt to stimulate the implantation more potently than LY-l17018 except groups treated with $625\;{\mu}g$ of the two drugs.

• Journal of the Korean Vacuum Society
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• v.4 no.S2
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• pp.100-105
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• 1995

Nitrogen implantation process has been applied for improvement of wear resistance of Zircaloy-4 fuel cladding materials. Nitrogen was implanted at 120keV to a total dose range of $1\times 10^{17}$ions/$\textrm{cm}^2$ to $1\times 10^{18}$ions/$\textrm{cm}^2$ at various temperatures between $270^{\circ}C$ and $671^{\circ}C$. The microstructure changes by nitrogen implantation were analyzed by XRD and AES and wear behavior was evaluated by performing ball-on-disc type wear testing at various loads and sliding velocities under unlubricated condition. Nitrogen implantation produced ZrNx nitride above $3\times 10^{17}$ions/$\textrm{cm}^2$ as well as heavy dislocations, which resluted in an increase in microhardness of the implanted surface of up to 1400 $H_k$ from 200 $H_k$ of unimplanted substrate. Hardness was also found to be increased with increasing implantation temperature up to 1760 $H_k$ at $620^{\circ}C$. The wear resistance was greatly improved as total ion dose and implantation temperature increased. The effective enhancement of wear resistance at high dose and temperature is believed to be due to the significant hardening associated with high degree of precipitation of Zr nitrides and generation of prismatic dislocation loops.

• Korean Journal of Head & Neck Oncology
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• v.23 no.1
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• pp.46-49
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• 2007

Soft tissue implantation of thyroid tissue is a very rare event. Needle tract implantation of thyroid carcinoma after fine-needle aspiration (FNA) biopsy has been occasionally reported, but implantation of benign thyroid tumor tissue is extremely rare. Rupture of thyroid tissues during surgery or trauma may cause the thyroid tissue to be implanted and result in multiple palpable nodules in soft tissue of the neck. Several reports have shown the possibility of implantation of normal or hyperplastic thyroid tissues in soft tissue. We herein report a case of implantation of adenomatous hyperplastic tissue in the neck along the trochar and previous operation site after endoscopic thyroid surgery, which was successfully treated by complete excision.