• Journal of the Korean Society for Heat Treatment
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• v.28 no.3
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• pp.134-138
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• 2015

Ag intermediated $TiO_2$ films were deposited by RF and DC magnetron sputtering and then vacuum annealed at 100, 200 and $300^{\circ}C$ for 30 minutes to investigate the effect of annealing temperature on the structural and optical properties of the films. For all depositions, the thickness of the $TiO_2$ and Ag films were kept constant at 24 and 15 nm by controlling the deposition time. As-deposited $TiO_2/Ag/TiO_2$ trilayer films have a weak crystalline and an optical reflectance in a near infrared wavelength region of 77.8%, while the films annealed at $300^{\circ}C$ show the polycrystalline structure and an increased mean optical reflectance of 80.4%. From the experimental results, it can be concluded that increasing the annealing temperature enhanced the structural and optical properties of the $TiO_2/Ag/TiO_2$ films.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.1-9
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• 2005

A stoichiometric mixture of evaporating materials for AgGaS₂ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, AgGaS₂ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were 590℃ and 440℃, respectively. The temperature dependence of the energy band gap of the AgGaS₂ obtained from the absorption spectra was well described by the Varshni's relation, E/sub g/(T) = 2.7284 eV - (8.695×10/sup -4/ eV/K)T²/(T + 332 K). After the as-grown AgGaS₂ single crystal thin films was annealed in Ag-, S-, and Ga-atmospheres, the origin of point defects of AgGaS₂ single crystal thin films has been investigated by the photoluminescence (PL) at 10 K. The native defects of V/sub Ag/, V/sub s/, Ag/sub int/, and S/sub int/ obtained by PL measurements were classified as a donors or accepters type. And we concluded that the heat-treatment in the Ag-atmosphere converted AgGaS₂ single crystal thin films to an optical n-type. Also, we confirmed that Ga in AgGaS₂/GaAs crystal thin films did not form the native defects because Ga in AgGaS₂ single crystal thin films existed in the form of stable bonds.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.2
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• pp.117-126
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• 2005

A stoichiometric mixture of evaporating materials for $AgGaS_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $AgGaS_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $590^{\circ}C\;and\;440^{\circ}C$, respectively The temperature dependence of the energy band gap of the $AgGaS_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7284 eV-(8.695{\times}10^{-4}eV/K)T^2/T(T+332K)$. After the as-grown $AgGaS_2$, single crystal thin films was annealed in Ag-, S-, and Ga-atmospheres, the origin of point defects of $AgGaS_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag},\;V_s,\;Ag_{int},\;and\;S_{int}$, obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaS_2$ single crystal thin films to an optical n-type. Also, we confirmed that Ga in $AgGaS_2$ crystal thin films did not form the native defects because Ga in $AgGaS_2$ single crystal thin films existed in the form of stable bonds.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.385-386
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• 2007

We prepared the Al doped ZnO coating Ag multilayer thin films on glass without substrate heating using FTS system. The structure of multilayer thin films has Al doped ZnO/Ag/Al doped ZnO(AZO/Ag/AZO). The thickness of top and bottom AZO thin films were fixed to 50 nm, respectively and controlled the thickness of Ag thin films with deposition time. As-doped multilayer thin films were prepared at 1mTorr and input power (DC) of 100W at room temperature. To investigate the film properties, we employed four-point probe, UVNIS spectrometer, X-ray diffractometer (XRD), scanning electron microscopy (SEM), Hall Effect measurement system and Atomic Force Microscope (AFM).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.101-102
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• 2006

A stoichiometric mixture of evaporating materials for $AgGaS_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films. $AgGaS_2$ mixed crystal was deposited on thoroughly etched semi-Insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $590^{\circ}C$ and $440^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaS_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7284 eV-(8.695{\times}10^{-4} eV/K)T^2/(T+332 K)$. After the as-grown $AgGaS_2$ single crystal thin films was annealed in Ag-, S-, and Ga-atmospheres, the origin of point defects of $AgGaS_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.11
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• pp.963-968
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• 2000

Magnetic properties and microstructures of Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films were investigated as a function of addition of element Ag, (X$\_$Ag/=0 to 6 at.%) and annealing temperature, T$\_$a/=300$\^{C}$ to 600$\^{C}$. In the case of adding Ag, magnetic properties of Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films were improved than those of Ag-free Fe$\_$93/Zr$_3$B$_4$thin films. The prominent soft magnetic properties with coercivity of 1.1 Oe, saturation magnetization of 2.2 T and permeability of 5400 at 50㎒ were obtained from Fe$\_$88/Zr$_3$B$_4$Ag$\_$5/ thin film annealed was lower than that of Fe-base or Co-base thin films reported previously. Such enhanced magnetic properties are presumably attributed to the format in ultra fine grains. Also, the reduced eddy current loss in the annealed sample is due to refined micro magnetic domains with increasing the amount of Ag in Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films.

• Journal of the Korean institute of surface engineering
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• v.52 no.3
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• pp.145-149
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• 2019

Transparent and conductive ZnO/Ag/SnO2 (ZAS) tri-layer films were deposited onto glass substrates at room temperature by using radio frequency (RF) and direct current (DC) magnetron sputtering. The thickness values of the ZnO and $SnO_2$ thin films were kept constant at 50 nm and the value for Ag interlayer was varied as 5, 10, 15, and 20 nm. In the XRD pattern the diffraction peaks were identified as the (002) and (103) planes of ZnO, while the (111), (200), (220), and (311) planes could be attributed to the Ag interlayer. The optical transmittance and electrical resistivity were dependent on the thickness of the Ag interlayer. The ZAS films with a 10 nm thick Ag interlayer exhibited a higher figure of merit than the other ZAS films prepared in this study. From the observed results, a ZAS film with a 10 nm thick Ag interlayer was believed to be an alternative transparent electrode candidate for various opto-electrical devices.

• Current Photovoltaic Research
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• v.10 no.1
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• pp.28-32
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• 2022

We investigated the optical and electrical characteristics of ITO/Ag/ITO (IAI) 3-layer thin films prepared by using RF/DC sputtering. To measure the thickness of all thin film samples, we used scanning electron microscopy. As a function of Ag thickness we characterized the optical transmittance and sheet resistance of the IAI samples by using UV-Visible spectroscopy and Hall measurement system, respectively. While the thickness of both ITO thin films in the 3-layered IAI samples were fixed at 50 nm, we varied Ag layer thickness in the range of 0 nm to 11 nm. The optical transmittance and sheet resistance of the 3-layered IAI thin films were found to vary strongly with the thickness of Ag film in the ITO (50 nm)/Ag(t₀)/ITO (50 nm) thin film. For the best transparent conducting oxide (TCO) electrode, we obtained a 3-layered ITO (50 nm)/Ag (t₀ = 8.5 nm)/ITO (50 nm) that showed an avrage optical transmittance, AVT = 90.12% in the visible light region of 380 nm to 780 nm and the sheet resistance, R_□ = 7.24 Ω/□.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2014-2018
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• 2016

Transparent, conductive electrode films, showing the particular characteristics of good conductivity and high transparency, are of considerable research interest because of their potential for use in opto-electronic applications, such as smart window, photovoltaic cells and flat panel displays. Multilayer transparent electrodes, having a much lower electrical resistance than widely-used transparent conducting oxide electrodes, were prepared by using RF/DC magnetron sputtering system. The multilayer structure consisted of three layers, [NiInZnO(NIZO)/Ag/NIZO]. The optical and electrical properties of the multilayered NIZO/Ag/NIZO structure were investigated in relation to the thickness of each layer. The optical and electrical characteristics of multilayer structures have been investigated as a function of the Ag and NIZO film thickness. High-quality transparent conductive films have been obtained, with sheet resistance of $9.8{\Omega}/sq$ for Ag film thickness of 8 nm. Also the multilayer films of inserted Ag 8 nm thickness showed a high optical transmittance above 93% in the visible range. The electrical and optical properties of the new multilayer films were mainly dependent on the thickness of Ag insertion layer.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.126-133
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• 1992

This study deals with the crystal growth and the optical characteristics of CdS thin films activatedby silver. CdS:Ag thin films were deposited by using an electron beam evaporation(EBE) technique in vacuumof 1.5X 10-'torr, voltage of 4 kV, current of 2.5 mA and substrate temperature of 250$^{\circ}$C CdS:Ag photoconductivefilms prepared by EBE method show high photoconductivity after annealing at about 550"c for 0.5 h in air andAr gas.The grain size of CdS:Ag thin films annealed in Ar atmosphere (1 atm) was grown over 1 ym and the thicknessof the films is 4-5 pm. The analysis of X-ray diffraction patterns shows that the crystal structures are hexagonal.The diffraction line by (00.2) plane can only be observed, indicating that c-axis of hexagonal grows preferentiallyperpendicular to the substrate. The profiles of photoluminescence spectra of CdS:Ag films show Gaussian typecurves at room temperature, the maximum peak spectral sensitivity of CdS:Ag is located at the wavelength of520 nm.We annealed CdS:Ag thin films in air and Ar vapor in order to make the CdS photoconductors having theintensive photocurrent, the broad distribution of the photocurrent spectrum and the large value of the ratioof the photocurrent (pc) to the dark current(dc). We found that CdS:Ag thin films annealed in air atmospherewas the best one.air atmosphere was the best one.