• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.10
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• pp.461-466
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• 2006

In the present work, we investigated the photodissolution and photodiffusion effect on the interface of Ag/chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film by measuring the absorption coefficient, the optical density, the resistance change of Ag layer. It was found that the photodissolutioniphotodiffution ratio depends on the magnitude of photon energy absorbed in the chalcogenide thin film and the depth of photodiffution was proportional to the square root of the exposed time. Also, we have investigated the holographic grating formation with P-polarization states on chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film and $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film. Holographic gratings have been formed using He-Ne laser (632.8 nm) which have a smaller energy than the optical energy gap, $E_g\;_{opt}$ of the film, i. e., an exposure of sub-bandgap light $(h{\upsilon} under P-polarization. As the results, we found that the diffraction efficiency on $As_{40}Ge_{10}Se_{15}S_{35}/Ag$ double layer structure thin film was more higher than that on single $As_{40}Ge_{10}Se_{15}S_{35}$ thin film. Also, we obtained that the maximum diffraction efficiency was 0.27 %, 1,000 sec on $As_{40}Ge_{10}Se_{15}S_{35}\;(1{\mu}m)/Ag$ (10 nm) double layer structure thin film by (P: P) polarized recording beam. It will offer lots of information for the photodoping mechanism and the analyses of chalcogenide thin films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.31 no.1
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• pp.55-60
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• 2018

Transparent conductive thin films (TCFs) are essential materials for solar cells, organic light-emitting diodes, and display panels. Indium tin oxide (ITO) is one of the most widely used commercial materials to create TCFs'; however, new materials that can possibly replace ITO at a lower cost and/or those possessing mechanical flexibility are urgently needed. Silver nanowire (AgNW) is one of those promising materials, as it is less expensive and possesses superior mechanical flexibility as compared to ITO. We used AgNW and sol-gel ZnO to fabricate composite thin films by spray coating. We propose two spray-coating methods: the 'metal-organic chemical vapor deposition (MOCVD)/AgNW' method and the Mixture method. These two methods are expected to be commercialized for high-quality and low-cost products, respectively.

• Korean Journal of Optics and Photonics
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• v.2 no.2
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• pp.59-66
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• 1991

Resonance angle and optimum thinckness of various thin metal films for surface plasmon resonance were calculated using an admittance diagram and optical constants and thickness of thin Ag films and Al films were determined by fitting the measured reflectance of surface plasmon resonance. Two wavelengths of an Ar ion laser were employed to select the unique optical constants which have the same thickness at two wavelengths. Also, when these films were exposed to the air, the shift of surface plasmon resonance was measured and the optical constants of modified thin films were determined.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.6
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• pp.429-435
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• 1999

The $SrTiO_3$ thin films were prepared on Ag/TiN-coated and p-type bare Si(100) substrates by r.f. magnetron sputtering deposition technique. The electrical properties of the deposited films were investigated, which controlling deposition parameters such as substrate temperature and film thickness. The electrical properties ofthe $SrTiO_3$ films were measured using the capacitance-voltage(C-V) technique. The thickness dependence of the electrical properties of the $SrTiO_3$ films was analyzed of the connection with the films in series. The substrate affected the crystal structure and texture characteristics of the $SrTiO_3$ films. The resistivity of the film, sandwiched between Al and Ag films was measured, as a function of the temperature.

• Journal of the Korean Society for Heat Treatment
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• v.30 no.4
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• pp.151-155
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• 2017

The ZTO single layer and ZTO/Ag/ZTO tri-layer films were deposited on glass substrates by using the radio frequency (RF) and direct current (DC) magnetron sputtering and then rapid thermal annealed (RTA) in a low pressure condition for 10 minutes at 150 and $300^{\circ}C$, respectively. As deposited tri-layer films show the 81.7% of visible transmittance and $4.88{\times}10^{-5}{\Omega}cm$ of electrical resistivity, while the films annealed at $300^{\circ}C$ show the increased visible transmittance of 82.8%. The electrical resistivity also decreased as low as $3.64{\times}10^{-5}{\Omega}cm$. From the observed results, it is concluded that rapid thermal annealing (RTA) is an attractive post-deposition process to optimize the opto-elecrtical properties of ZTO/Ag/ZTO tri-layer films for the various display applications.

• ETRI Journal
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• v.19 no.2
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• pp.71-81
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• 1997

We report on the room-temperature-growth of highly uniform and ultrathin Ag films on Sb-terminated Si(111) surfaces, as evidenced from a scanning tunneling microscopy (STM) study in an UHV system. With predeposition of one monolayer (ML) of Sb, uniform growth of Ag islands was observed at room temperature. The Sb layer suppresses the surface diffusion of Ag atoms on Si surface and increases the Ag island density, and then the increased island density is believed to cause coalescence of Ag islands before the beginning of multilayer growth in higher coverages, resulting in the growth of atomically flat and uniform islands on the Sb surfactant layer.

• Journal of Surface Science and Engineering
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• v.35 no.2
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• pp.107-112
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• 2002

We have studied diffusion behavior of NiFe/Ag bilayer deposited by on silicon Ion Beam Sputtering methods. The diffusion behavior of NiFe and Ag in NiFe/Ag thin film is analyzed by Medium Energy Ion Scattering Spectroscopy. For samples without Ta underlayer, silicides such as Ni-Si or Fe-Si were formed at Si substrate and NiFe interface. In contrast, Ag predominantly diffused into the NiFe layer probably through their grain boundaries for Ta underlayered samples.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.217-222
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• 1998

Coating films of $SiO_2-TiO_2-AgO$ have been prepared on soda-lime-silica slide glasses and single crystal silicon wafer by the sol-gel method using a spin-coating technique. Commercially available tetraethyl orthosilicate, titanium trichloride, and silver-nitrates were used as starting materials. The heat treatment temperature of this coating films was $500^{\circ}C$ properly, obtained from TG-DTA result. The films with thickness of 310 nm were prepared by 5 times coating. In the case of l0 mol% AgO, the film showed a crack-free and smooth surface, but the higher Ago content exhibited the more pin hole and the segregated cluster of AgO. The IR absorbance of the films decreased in the range of 400 nm to 700 nm with the increase of annealing temperature. And the reflectance of the coating films decreased and the color was changed light yellow to white yellow with the increase of Ago content.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4221-4226
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• 2011

Honeycomb-patterned polyvinypyrrolidone (PVP) thin films coated with nanometer-sized silver particles were prepared using honeycomb-patterned polystyrene (PS) template films fabricated by casting a polystyrene solution under humid condition. Silver was first metallized on the patterned PS films via silver nitrate ($AgNO_3$) reduction using tetrathiafulvalene (TTF) and a small amount of PVP as the reductant and dispersing agent, respectively. The effects of $AgNO_3$, TTF, and PVP solution concentrations during the reduction process in acetonitrile were determined to obtain a uniform silver-coated honeycomb-patterned PS film. Second, the silver-metallized patterned porous PS films were filled with high PVP concentration solutions via the spincoating process. Silver-coated patterned PVP films were obtained by peeling off the PVP layer from the template PS film after drying. The results show that the honeycomb-patterned PVP films uniformly coated with silver particles are conveniently obtained using the silver-coated patterned PS template, although the direct fabrication of these films using water droplets under humid conditions was not feasible because of the water solubility of PVP.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.67-68
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• 2009

In this study, we studied the nature of thin films formed by photodoping chalcogenide materials with for use in programmable metallization cell devices, a type of ReRAM. We investigated the resistance of Ag-doped chalcogenide thin films varied in the applied voltage bias direction from about $1\;M{\Omega}$ to several hundreds of $\Omega$. As a result of these resistance change effects, it was found that these effects agreed with PMC-RAM. The results imply that a Ag-rich phase separates owing to the reaction of Ag with free atoms from the chalcogenide materials.