• Design & Manufacturing
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• v.2 no.3
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• pp.6-9
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• 2008

This paper describes the process of structure analysis and injection molding analysis to manufacture the forming injection dies for huge glass insert. Factors such as filling time, filling pressure, material temperature, shrinkage, warpage were investigated by using the analysis software, Moldflow. Runner system and cavity structure were designed and manufactured through the results of deformation analysis data for glass insert. Filling time and filling pressure were analyzed in 3.756sec and 43.37MPa.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.48-53
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• 2014

We have formulated hexagonal-shaped gold nanoplates in a single-step for photothermal therapy that gold ions to gold particles using pyrenyl dextran as reducible stabilizer and template. They exhibit anisotropic structure with broad surface plasmon resonance (SPR) band into near-infrared (NIR) spectrum enabling photothermal therapy. These gold nanoplates are also confirmed biocompatibility and high uptake efficiency due to binding with dextran molecules on the surface of gold nanoplates and cells. From in vitro phtothermal ablation study under NIR laser, gold nanoplates have the potential to use as photothermal agents.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.209-209
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• 2000

Carbon nanotubes have been intensively investigated for its fundamental and technical importances. Structural diversities and the related diverse physical properties with large aspect ratios are fascinating, For instance carbon nanotubes are metal and semiconductors depending on its chirality and furthermore the band gap can be tailored by the diamters. Several issues on its fundamental properties have been discussed. We will review some fundamental problems for band structures, molecular quantum wires, homojunctions, single electron tunneling, and quantum conductance. Several issues related to syntheis of carbon nanotubes including arc discharge, chemical vapor deposition, laser ablation will be extentively discussed. We will further review the applicability of carbon nanotubes on resonator, nanobalance, FET-type transistor, field emission displays electrode for secondary battery and hydrogen storage.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.211.1-211.1
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• 2013

We fabricate the conductive zinc oxide(ZnO) thin film using UV-enhanced atomic layer deposition. ZnO is semiconductor with a wide band gap(3.37eV) and transparent in the visible region. ZnO can be deposited with various method, such as metal organic chemical vapour deposition, magnetron sputtering and pulsed laser ablation deposition. In this experiment, ZnO thin films was deposited by atomic layer deposition using diethylzinc (DEZ) and D.I water as precursors with UV irradiation during water dosing. As a function of UV exposure time, the resistivity of ZnO thin films decreased dramatically. We were able to confirm that UV irradiation is one of the effective way to improve conductivity of ZnO thin film. The resistivity was investigated by 4 point probe. Additionally, we confirm the thin film composition is ZnO by X-ray photoelectron spectroscopy. We anticipate that this UV-enhanced ZnO thin film can be applied to electronics or photonic devices as transparent electrode.

• Journal of Pharmacopuncture
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• v.22 no.3
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• pp.200-203
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• 2019

Syringoma is a benign eccrine sweat gland tumor that predominantly appears in females during puberty with multiple smooth papules measuring 1-2 mm in diameter. Common locations are on lower eyelids and cheeks. Vulvar syringoma is quite a rare, occurring condition with only a few cases reported. Here, we are reporting a case of 31-year-old female with vulvar syringoma associated with pruritus. The lesion was treated with carbon dioxide (CO2) laser ablation and 50% trichloroacetic acid (TCA) chemical peeling. Jaungo was used for wound care after laser abrasion. The combination treatment was effective for removing syringoma lesions. Post laser management with fusidic acid cream and jaungo cream was sufficient to prevent infection and promote wound healing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.6
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• pp.523-530
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• 2017

Laser-Induced Breakdown Spectroscopy (LIBS) which a plasma is irradiated at a specific wavelength depending on the material when a high-energy laser is irradiated, and a Raman spectroscopy which measures rotation and vibration in molecules as light-scattering phenomenon occurs, are attracting attention as a space exploration technology because of the advantages of high accuracy and real-time analysis, and the ability to perform long-range detection. In this study, the tendency of the laser spectrum according to the change of the soil component was analyzed by laser spectroscopy and the two - dimensional chemical distribution was conducted based on the trend of laser spectrum. We have also established the environment of Mars (4-7 torr) and lunar atmosphere (<1 torr) in experimental setup, to prove that it is possible to measure by difference of soil chemical composition using LIBS and Raman spectroscopy even in artificial space environment.

• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.953-958
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• 2010

A laser ablation-molecular beam/reflectron time-of-flight mass spectrometric technique was used to investigate the ion-molecule reactions that proceed within $Ti^+(CH_3COCH_3)_n$ heterocluster ions. The reactions of $Ti^+$ with $CH_3COCH_3$ clusters were found to be dominated exclusively by an oxidation reaction, which produced $TiO^+(CH_3COCH_3)_n$ clusters. These ions were attributed to the insertion of a $Ti^+$ ion into the C=O bond of the acetone molecule within the heteroclusters, followed by $C_3H_6$ elimination. The mass spectra also indicated the formation of minor sequences of heterocluster ions with the formulas $Ti^+(C_3H_4O)(CH_3COCH_3)_n$ and $TiO^+(OH)(CH_3COCH_3)_n$, which could be attributed to C-H bond insertion followed by $H_2$ elimination and to the sequential OH abstraction by the $TiO^+$ ion, respectively. Density functional theory calculations were carried out to model the structures and binding energies of both the association complexes and the relevant reaction products. The reaction pathways and energetics of the $TiO^+\;+\;CH_2CHCH_3$ product channel are presented.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.383-396
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• 2017

The photothermal therapy is a method of cell ablation using the heat converted from the incident light by photothermal transducers. It offers a selective treatment to desired abnormal cells, in particular, tumor tissues. Among various photothermal agents, gold nanoparticles (Au NPs) have received enormous attention due to their unique physicochemical property over last two decades. In this review, we address research strategies and methods to improve treatment efficacy by organizing recent research works. We mainly focus on research works to enhance light-to-heat conversion via optimizing the morphology of Au NPs and related assemblies as well as the strategies to deliver Au NPs efficiently to specific targets. We also introduce convergence research efforts to combine Au NP-mediated photothermal treatment and other functions such as diagnostic capabilities and other therapeutic methods.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.421.1-421.1
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• 2016

We studied indium-doped zinc oxide (IZO) film grown by atomic layer deposition (ALD) as transparent conductive oxide (TCO). A variety of TCO layer, such as ZnO:Al (AZO), InSnO2(ITO), Zn (O,S) etc, has been grown by various method, such as ALD, chemical vapor deposition (CVD), sputtering, laser ablation, sol-gel technique, etc. Among many deposition methods, ALD has various advantages such as uniformity of film thickness, film composition, conformality, and low temperature deposition, as compared with other techniques. In this study, we deposited indium-doped zinc oxide thin films using diethyl[bis(trimethylsilyl)amido]indium [Et2InN(TMS)2] as indium precursor, DEZn as zinc precursor and H2O as oxidant for ALD and investigated the optical and electrical properties of IZO films. As an alternative, this liquid In precursor would has several advantages in indium oxide thin-film processes by ALD, especially for low resistance indium oxide thin film and high deposition rate as compared to InCp, InCl3, TMIn precursors etc. We found out that Indium oxide films grown by Et2InN(TMS)2 and H2O precursor show ALD growth mode and ALD growth window. We also found out the different growth rate of Indium oxide as the substrate and investigated the effect of the substrate on Indium oxide growth.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.120.2-120.2
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• 2015

We propose a novel direct writing technique with a femtosecond laser enabling selective modification of not only the morphology of conducting polymer thin films but also the orientation and alignment of the polymer crystal. Surface relief gratings resulting from photoexpansion on P3HT:PCBM and PEDOT:PSS thin films were fabricated by femtosecond laser direct writing. The photoexpansion was induced at laser fluence below the ablation threshold of the thin film. The morphology (size and shape) of photoexpansion could be quantitatively controlled by laser writing parameters such as focused beam size, writing speed, and laser fluence. GIWAX results showed that face-on P3HT crystals were largely increased in the photoexpansion in comparison with pristine region of the thin film. In addition, the face-on P3HTs in the photoexpansion were aligned with their orientation along the polarization of the laser. The micro-RAMAN spectra confirmed that neither chemical composition change nor the polymer chain breaking was observable after femtosecond laser irradiation. We believe that this laser direct writing technique opens a new door to the fabrication of more efficient OPVs via non-contact, toxic-free approach.