• Bulletin of the Korean Chemical Society
• /
• v.26 no.3
• /
• pp.440-446
• /
• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

• Analytical Science and Technology
• /
• v.5 no.3
• /
• pp.277-283
• /
• 1992

Acid effects on the ICP-AES signals are studied as the concentrations of nitric acid, hydrochloric acid, sulfuric acid, and 1:1 mixture of nitric acid and hydrochloric acid are changed. Almost all analyte signals are depressed. The extent of the depression due to the pressence of the acids became to be pecular when the acid concentration was over 1%. Among the acids used, the suppression due to sulfuric acid is most severe and unexpectable. The ratios of the analyte signal to Ar signal and the Mg II signal to Mg I signal are measured as the concentration of the acids changed. In this study, it is proved that the main reason of the signal reduction is the change in the nebulization efficiency, for example, droplet size distribution, viscosity and surface tension variation, not the alteration of plasma excitation characteristics. There was no relationship found between ionization potential and analyte signal reduction in ICP-MS.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2015.11a
• /
• pp.43-73
• /
• 2015

유도결합 플라즈마(inductively coupled plasma: ICP)를 이용한 물리 및 화학 증착법으로 제작된 박막 재료는 우수한 기계적, 화학적, 물리적 성질 때문에 자동차 부품이나 공구재료의 내마모, 저마찰 경질코팅, 그리고 디스플레이용 코팅 뿐만 아니라 수소 연료전지의 분리막 성능 향상을 위한 코팅, 그리고 기판에 아주 균일한 크기의 나노 분말을 형성 시키는 곳에도 응용을 할 수 있음을 여러 사례를 중심으로 살펴 본다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.17 no.7
• /
• pp.701-707
• /
• 2004

High aspect ratio silicon structure through deep silicon etching process have become indispensable for advanced MEMS applications. In this paper, we present the results of modified Bosch process to obtain anisotropic silicon structure with conventional Inductively Coupled Plasma (ICP) etcher instead of the expensive Bosch process systems. In modified Bosch process, etching step ($SFsub6$) / sidewall passivation ($Csub4Fsub8$) step time is much longer than commercialized Bosch scheme and process transition time is introduced between process steps to improve gas switching and RF power delivery efficiency. To optimize process parameters, etching ($SFsub6$) / sidewall passivation ($Csub4Fsub8$) time and ion energy effects on etching profile was investigated. Etch profile strongly depends on the period of etch / passivation and ion energy. Furthermore, substrate temperature during etching process was found to be an important parameter determining etching profile. Test structures with different pattern size have been etched for the comparison of the aspect ratio dependent etch rate and the formation of silicon grass. At optimized process condition, micropatterns etched with modified Bosch process showed nearly vertical sidewall and no silicon grass formation with etch rate of 1.2 ${\mu}{\textrm}{m}$/ min and the size of scallop of 250 nm.

• Nuclear Engineering and Technology
• /
• v.45 no.3
• /
• pp.415-420
• /
• 2013

A determination method for $^{237}Np$ in spent nuclear fuel samples was developed using an isotope dilution method with $^{239}Np$ as a spike. In this method, inductively coupled plasma mass spectrometry (ICP-MS) was taken for the $^{237}Np$ instead of the previously used alpha spectrometry. $^{237}Np$ and $^{239}Np$ were measured by ICP-MS and gamma spectrometry, respectively. The recovery yield of $^{237}Np$ in synthetic samples was $95.9{\pm}9.7$% (1S, n=4). The $^{237}Np$ contents in the spent fuel samples were 0.15, 0.25, and $1.06{\mu}g/mgU$ and these values were compared with those from ORIGEN-2 code. A fairly good agreement between the measurements (m) and calculations (c) was obtained, giving ratios (m/c) of 0.93, 1.12 and 1.25 for the three PWR spent fuel samples with burnups of 16.7, 19.0, and 55.9 GWd/MtU, respectively.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.5C no.3
• /
• pp.124-130
• /
• 2005

In this paper, we designed a cylindrical type light source having an electromagnetic principle of inductively coupled plasma, and measured its electrical-optical properties. Using the transformer principle, an electrically equivalent circuit cylindrical type light source was analyzed. According to the parameters of electromagnetic induction, which were diameter of coil with cpO.3$\~$ 1.2mm, number of turns with 4$\~$ 12 turns, distance with 40$\~$ l20mm and RF power with 10$\~$ 150W, the electrical .md optical properties were measured. When the diameter of the coil was cp0.3mm, number of turns was 8 and distance was 40mm, and the maximum brightness of 29,730 cd/m$^{2}$ was shown with RF power l50W. The relationship between electromagnetic induction and plasma discharges was demonstrated using the mode transition from E-mode to H-mode

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.05b
• /
• pp.61-64
• /
• 2004

Recently, the RF inductive discharge or inductively coupled plasma (ICP) continues to attract growing attention as an effective plasma source in many industrial applications, the best known of which are plasma processing and lighting technology. To the point of lighting sources, the electrodeless fluorescent lamps utilizing an inductively coupled plasma (ICP) have been objects of interest and research during the last decades, mainly because of their potential for extremely long life, high lamp efficacies, rapid power switching response. The electrodeless fluorescent lamp that is dealt with in this work comprises a bulb filled with rare gas and amalgam of vaporizable metal and has a coil provided with a winding around the ferrite. Current through a coil produces a magnetic field in the discharge space. The changing magnetic flux then produces an azimuthal electric field E around the coil, according to Faraday's laws of magnetic induction.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.188-189
• /
• 2007

The etching characteristics of $Al_2O_3$ films using the inductively coupled plasma (ICP) was investigated. The etch gas was the mixture of $BCl_3$ and He. The effect of ICP source and bias powers on etch rate and etch selectivity to polycrystalline Si was investigated in the etch process of $Al_2O_3$. The etch rate of $Al_2O_3$ film was 23nm/min when the source power and bias power were 600W and 60W, respectively. The results also indicated that the etch selectivity to polycrystalline Si could not be enhanced to be higher than 1.0 by changing the ICP source power and bias power, under the experimental conditions used in the present work. Based on plasma parameters extracted from Langmuir probe data, the etching mechanism of $Al_2O_3$ film was discussed in detail.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.8 no.3
• /
• pp.487-492
• /
• 1998

Ultrafine particles of $SnO_2$ or $(Sn,Ti)O_2$ and thin films of $SnO_2$ were synthesized by introducing aqueous tin chloride solution into a high temperature argon inductively coupled plasma (ICP) generated under ambient pressure (the spray-ICP technique). As-deposited $SnO_2$ particles from each concentration of solution were all tetragonal $SnO_2$ crystallline phase and their mean size decreased in proportion to the increase of solution concentration. The mean size of $SnO_2$ particles was in the 10~40 nm range.

• Journal of the Korean institute of surface engineering
• /
• v.37 no.3
• /
• pp.146-151
• /
• 2004

Indium tin oxide (ITO) is widely used to make a transparent conducting film for various display devices and opto-electric devices. In this study, ITO films on glass substrate were fabricated by inductively coupled plasma (ICP) assisted dc magnetron sputtering. A two-turn rf coil was inserted in the process chamber between the substrate and magnetron for the generation of ICP. The substrates were not heated intentionally. Subsequent post-annealing treatment for as-deposited ITO films was not performed. Low-temperature deposition technique is required for ITO films to be used with heat sensitive plastic substrates, such as the polycarbonate and acrylic substrates used in LCD devices. The surface roughness of the ITO films is also an important feature in the application of OLEDs along with the use of a low temperature deposition technique. In order to obtain optimum ITO thin film properties at low temperature, the depositions were carried out at different condition in changing of Ar and $O_2$ gas mixtures, ICP power. The electrical, optical and structural properties of the deposited films were characterized by four-point probe, UV/VIS spectrophotometer, atomic force microscopy(AFM) and x-ray diffraction (XRD). The electrical resistivity of the films was -l0$^{-4}$ $\Omega$cm and the optical transmittance in the visible range was ＞85%. The surface roughness ( $R_{rms}$) was -20$\AA$.>.