• 한국세라믹학회지
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• 제42권12호
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• pp.865-871
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• 2005

Submicron thick solid electrolyte membrane is essential to the implementation of low temperature solid oxide fuel cell, and, therefore, development of new electrode structures is necessary for the submicron thick solid electrolyte deposition while providing functions as current collector and fuel transport channel. In this research, a nickel membrane with multi-stage nano hole array has been produced via modified two step replication process. The obtained membrane has practical size of 12mm diameter and $50{\mu}m$ thickness. The multi-stage nature provides 20nm pores on one side and 200nm on the other side. The 20nm side provides catalyst layer and $30\~40\%$ planar porosity was measured. The successful deposition of submicron thick yttria stabilized zirconia membrane on the substrate shows the possibility of achieving a low temperature solid oxide fuel cell.

• 한국재료학회지
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• 제27권5호
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• pp.289-293
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• 2017

$Y_2Ti_2O_7$ nanoparticles (0.3 mol%) have been successfully synthesized by the co-precipitation process. The samples, adjusted to pH7 with ammonia solution as catalyst and calcined at $700{\sim}900^{\circ}C$, exhibit very fine particles with close to spherical shape and average size of 10-30 nm. It was possible to control the size of the synthesized $Y_2Ti_2O_7$ particles by manipulating the conditions. The $Y_2Ti_2O_7$ nanoparticles were coated on a glass substrate by a dipping coating process with inorganic binder. The $Y_2Ti_2O_7$ solution coated on the glass substrate had excellent adhesion of 5B; pencil hardness test results indicated an excellent hardness of 6H. The thickness of the thick film was about $30{\mu}m$. Decomposition of MB on the $Y_2Ti_2O_7$ thin film shows that the photocatalytic properties were excellent.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.3-4
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• 2005

The Pseudo-MOSFET measurements technique has been used for the electrical characterization of the nano SOL Silicon islands for the Pseudo-MOS measurements were fabricated by selective etching of surface silicon film with dry or wet etching to examine the effects of the etching process on the device properties. The characteristics of the Pseudo-MOS was not changed greatly in the case of thick SOI film which was 205 nm. However the characteristics of the device was dependent on etching process in the case of less than 100 nm thick SOI film. The sub 100nm SOI was obtained by thinning the silicon film of standard thick SOI. The thickness of SOI film was varied from 88 nm to 44 nm by chemical etching. The etching process effects on the properties of pseudo-MOSFET characteristics, such as mobility, turn-on voltage, and drain current transient. The etching process dependency is greater in the thinner SOI and related to original SOI wafer quality.

• 센서학회지
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• 제18권3호
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• pp.239-244
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• 2009

We fabricated nano-templates by low temperature BCP(block copolymer) process at 180 $^{\circ}C$, then we deposited 10 nm-thick $TiO_2$ layers with ALD(atomic layer deposition) at low temperature of 150 $^{\circ}C$. Through FE-SEM analysis, we confirmed the successful formation of the groove-type(width of crest : 30 nm, width of trough : 18 nm) and the cylinder-type(diameter : 10 nm, distance between hole : 25 nm) templates. Moreover, after $TiO_2$-ALD processing, we confirmed the deposition of the uniform nano layers of $TiO_2$ on the nano-templates. Through AFM analysis, the pitches of the crest-through(in groove-type) and hole-hole(in cylinder-type) were the same before and after $TiO_2$-ALD processing. In addition, we indirectly determined the existence of the uniform $TiO_2$ layers on nano-templates as the surface roughness decreased drastically. We successfully fabricated nano-template at low temperature and confirmed that the three-dimensional nano-structure for sensor application could be achieved by $TiO_2$-ALD processing at extremely low temperature of 150 $^{\circ}C$.

• 한국재료학회지
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• 제17권6호
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• pp.323-330
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• 2007

We fabricated thermaly evaporated 10 nmNi/(poly)Si films to investigate the energy saving property of silicides formed by rapid thermal annealing (RTA) at the temperature of $300{\sim}1200^{\circ}C$ for 40 seconds. Moreover, we fabricated $10{\sim}50$ nm-thick ITO/Si films with a rf-sputter as reference films. A four-point tester was used to investigate the sheet resistance. A transmission electron microscope (TEM) and an X-ray diffractometer were used for the determination of cross sectional microstructure and phase changes. A UV-VISNIR and FT-IR (Fourier transform infrared rays spectroscopy) were employed for near-IR and middle-IR absorbance. Through TEM analysis, we confirmed $20{\sim}70nm-thick$ silicide layers formed on the single and polycrystalline silicon substrates. Nickel silicides and ITO films on the single silicon substrates showed almost similar absorbance in near-IR region, while nickel silicides on polycrystalline silicon substrate showed superior absorbance above 850 nm near-IR region to ITO films. Nickel silicide on polycrystalline substrate also showed better absorbance in middle IR region than ITO. Our result implies that nano-thick nickel silicides may have exellent absorbing capacity in near-IR and middle-IR region.

• 대한금속재료학회지
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• 제46권11호
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• pp.755-761
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• 2008

We fabricated thermally evaporated 10 nm-Ni/1 nm-Ir/(poly)Si films to investigate the energy saving property of silicides formed by rapid thermal annealing (RTA) at the temperature range of $300{\sim}1200^{\circ}C$ for 40 seconds. Moreover, we fabricated 100 nm-thick ITO/(poly)Si films with an rf-sputter as references. A transmission electron microscope (TEM) and an X-ray diffractometer were used to determine cross-sectional microstructure and phase changes. A UV-VIS-NIR and FT-IR (Fourier transform infrared spectroscopy) were employed for near-IR and middle-IR absorbance. Through TEM analysis, we confirmed 20~65 nm-thick silicide layers formed on the single and polycrystalline silicon substrates. Ir-inserted nickel silicide on single crystalline substrate showed almost the same absorbance in near IR region as well as ITO, but Ir-inserted nickel silicide on polycrystalline substrate, which had the uniform absorbance in specific region, showed better absorbance in near IR region than ITO. The Ir-inserted nickel silicide on polycrystalline substrate particularly showed better absorbance in middle IR region than ITO. The results imply that nano-thick Ir-inserted nickel silicides may have excellent absorbing capacity in near-IR and middle-IR region.

• 한국전기전자재료학회논문지
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• 제22권4호
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• pp.297-302
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• 2009

We have successfully fabricated the alumina thick films using inkjet printing processes without a high temperature sintering process. Alumina suspension as dielectric ink was formulated by combining nano-sized alumina powders with an anionic polymer dispersant in formamide/water as co-solvent. The thickness of the printed alumina thick film was measured at around 5 um by field emission scanning electron microscope. The calculated packing density of 68.5 % from the printed alumina thick film was much higher than the same films fabricated by conventional casting or dip coating processes. Q factor of the dielectrics thick film infiltrated with cyanate ester resin was evaluated by impedance analyzer.

• 한국표면공학회지
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• 제56권5호
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• pp.335-340
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• 2023

Quinary component of 3㎛ thick Ti-Al-Si-Cu-N films were deposited onto WC-Co and Si wafer substrates by using an arc ion plating(AIP) system. In this study, the influence of copper(Cu) contents on the mechanical properties and microstructure of the films were investigated. The hardness of the films with 3.1 at.% Cu addition exhibited the hardness value of above 42 GPa due to the microstructural change as well as the solid-solution hardening. The instrumental analyses revealed that the deposited film with Cu content of 3.1 at.% was a nano-composites with nano-sized crystallites (5-7 nm in dia.) and a thin layer of amorphous Si₃N₄ phase.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.30-30
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• 2001

• 한국재료학회지
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• 제18권10호
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• pp.515-520
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• 2008

We fabricated 10 nm-$TiO_2$ thin films for DSSC (dye sensitized solar cell) electrode application using ALD (atomic layer deposition) method at the low temperatures of $150^{\circ}\;and\;250^{\circ}$. We characterized the crosssectional microstructure, phase, chemical binding energy, and absorption of the $TiO_2$ using TEM, HRXRD, XPS, and UV-VIS-NIR, respectively. TEM analysis showed a 10 nm-thick flat and uniform $TiO_2$ thin film regardless of the deposition temperatures. Through XPS analysis, it was found that the stoichiometric $TiO_2$ phase was formed and confirmed by measuring main characteristic peaks of Ti $2p^1$, Ti $2p^3$, and O 1s indicating the binding energy status. Through UV-VIS-NIR analysis, ALD-$TiO_2$ thin films were found to have a band gap of 3.4 eV resulting in the absorption edges at 360 nm, while the conventional $TiO_2$ films had a band gap of 3.0 eV (rutile)${\sim}$3.2 eV (anatase) with the absorption edges at 380 nm and 410 nm. Our results implied that the newly proposed nano-thick $TiO_2$ film using an ALD process at $150^{\circ}$ had almost the same properties as thsose of film at $250^{\circ}$. Therefore, we confirmed that the ALD-processed $TiO_2$ thin film with nano-thickness formed at low temperatures might be suitable for the electrode process of flexible devices.