• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.1
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• pp.146-151
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• 1995

We have studied the fabrication self aligned atmospheric pressure(AP) CVD a-Si thin film transistor with source-drain ohmic contact by using ion shower doping method. The conductivity is 6*10$^{-2}$S/cm when the acceleration voltage, doping time and doping temperature are 6kV, 90s and 350.deg. C, respectively. We obtained the field effect mobility of 1.3cm$^{2}$/Vs and the threshold voltage of 7V.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.212-222
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• 1992

To use polycrystalline Si Thin Film Transistor (poly-Si TFT) in high density SRAM instead of High Load Resistor (HLR), TFT is needed to show good electrical characteristics such as large carrier mobility, low leakage current, high driver current and low subthreshold swing. To satisfy these electrical characteristics, the trap state density must be reduced in the channel poly. Technological issues pertinent to the channel poly fabrication process are investigated and discussed. They are solid phase growth (SPG), Si-ion implantation, laser annealing and hydrogenation. The electrical properties of several CVD oxides used as the gate oxide of TFT are compared. The dependence of the electrical characteristics of TFT on source-drain ion-implantation dose, drain offset length and dopant lateral diffusion are also described.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.361-363
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• 2005

The transient current of STN-LCD cells was measured and simulated to characterize ionic behavior in LCD cells. An experiment was performed to investigate the contribution of LC material and PI trapping effect to mobile ions in the LC layer. We observed that most of ions are trapped on the PI surface rather than stay in the LC layer in case of normal STN-LCD, and PI surface favors larger ions in general. A linear correlation of ion density and $V_50$ shift of the Transmission-Voltage (TV) curve between 30Hz and 1kHz at typical ion mobility was found.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.5
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• pp.196-203
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• 2005

A semi-empirical method to determine the electrostatic characteristics of a diode type corona aerosol charger based on ion current measurement and electrostatic charging theory was presented. Results from mathematical model were in agreement with those from experimental investigation of the charger. Current-voltage characteristics, $N_{i}t$ product and charge distribution against aerosol size were obtained. It was shown that the space charge was significant and must be taken into account at high ion number concentration and low flow rate. Additionally, significant particle loss was evident for particles smaller than 20 nm in diameter where their electrical mobility was high. Increase in charging efficiency may be achieved by introducing surrounding sheath flow and applying AC high voltage. Overall, the approach was found to be useful in characterizing the aerosol charger.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.546-548
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• 1987

We have studied 1iquid phase regrowth of phosphorus ion implanted silicon films on insulator (SOI) by rapid thermal annealing (RTA) method. Many twin boundaries were observed on the regrown silicon layer and mobility of the layer was increased from $14\;cm^2/v.sec$ to $38\;cm^2/v.sec$ after annealing at $1150^{\circ}C$ for 15 sec.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.476-479
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• 2000

In this study, mesh-type PECVD system was suggested to minimize the hydrogen concentration. The main structural difference between the triode system and a conventional system is that a mesh was attached to the substrate holding electrode. We investigated several conditions to compare with conventional PECVD. The main effect of mesh was to minimize the substrate damage by ion bombardment and to enhance the surface reaction to induce hydrogen desorption. It was also found that hydrogen concentration decreased but deposition rate increased as increasing applied dias. Applied DC bias enhanced sputtering process. Intense ion bombardment causes the weakly bonded hydrogen or hydrogen-containing species to leave the growing film and increased adatom mobility. Furthermore, addition of hydrogen gas enhance the surface diffusion of adatom. The structural properties of poly-Si films were analyzed by scanning electron microscopy(SEM).

• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.254-260
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• 2022

Trimethylammonium tetrafluoroborate (TriMA BF₄), consisting of the smallest trialkylammonium ion, was investigated for use in electrochemical double-layer capacitors. Despite the presence of a proton in TriMA⁺, cycle life tests in acetonitrile (AN) and -butyrolactone (GBL) showed a good capacity retention with a 1.8 V cut-off voltage. The rate of electrolysis of TriMA BF₄ in GBL was lower than that in AN because of the lower conductivity in GBL. As a consequence, the cells based on GBL achieved a higher capacitance and longer life than those with AN. TriMA BF₄ had a higher conductivity and lower viscosity than the quaternary salt tetraethylammonium tetrafluoroborate in GBL, as well as higher ionic mobility, these factors resulted in a higher rate capability.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.336-336
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• 2004

EDTA contained in decontamination wastes can cause complexation of radioactive captions resulting from its various treatment process such as chemical precipitation, and ion exchange etc. It might also import for elevated teachability and higher mobility of cationic contaminants from conditioned wastes such as waste immobilized in cement or other matrices. Therefore, various cheated or unchlelated EDTAS must be treated to environmentally safe materials.(omitted)

• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.249-252
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• 2004

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2383-2385
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• 2010