• Korean Journal of Materials Research
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• v.10 no.9
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• pp.607-611
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• 2000

Zr modified $(Ba_{1-x},Sr_x)TiO_3$ thin films as capacitor for high density DRAM were deposited by r.f. magnetron sputtering. The films deposited at various chamber pressure exhibited a polycrystalline structure. The Zr/Ti ratio of the films increased significantly with decreasing the chamber pressure and this variation affected the microstructure and surface roughness of films When chamber pressure increased dielectric constant of the films effected due to decrease of Zr. The thin films prepared in this study show dielectric constant of 380 to 525 at 100KHz. The variation of capacitance and polarization measured as a function of bias voltage suggested that all films were paraelectric phases. Leakage current exhibited smaller value as chamber pressure decrease and the leakage current density of the films deposited above 10mTorr was $10^{-7}~10^{-8}A/cm^2$ order at 200kV/cm. $(Ba_{1-x},Sr_x)(Ti_{1-y},Zr_y)O_3$ thin films in this study appeared to be potential thin film capacitor for high density DRAM.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1290-1292
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• 1995

A cylindrical-post magnetron sputtering system was designed for pipe inner coating. The discharge condition was depended on the gas pressure, magnetic field and pipe diameter. At given discharge current, discharge voltage increased a little with pipe diameter. The electron temperature and floating potential increased with magnetic field. The impact ion energy on the pipe increased with bias voltage. The TiN thin-film of $2{\mu}m$ thickness was formed by cylindrical-post magnetron sputtering system under the conditions of the pressure of 5mTorr, the applied voltage of 700V, the discharge current of 500mA, the magnetic field of 300G, and the bias voltage of -100V.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.201-202
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• 2009

ZnO:Al transparent conductive films for solar cells were deposited on the glass substrates at room temperature by facing target sputtering (FTS) method. The sputtering targets were 100 mm diameter disks of 2w.t..%. AZO and Zn metal. ZnO:Al thin films were deposited as a function film thickness. A base pressure was $2{\times}10^{-6}$torr, and a working pressure was 1mTorr. The properties of thin films on the structural, electrical and optical properties of the deposited films were investigated using a four-point probe (Chang-min), an X-ray diffraction (Rigaku), a Hall Effect measurement (Ecopia), an UV/VIS spectrometer (HP) and a $\alpha$-step (Tencor). The lowest resistivity of film was $5.67{\times}10^{-4}[{\Omega}-cm]$ at 500nm. The average transmittance of over 80% was seen in the visible range.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.8
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• pp.666-670
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• 2007

Aluminuim doped zinc oxide(ZnO:AL)Films have been prepared on Polyimide(PI) and Coming 7059 glass substrates by r.f. magnetron sputtering method. The structural of the ZnO:Al films were studied in accordance with various deposition R.F power and working pressure by XRD, SEM. And The electrical and optical properties of ZnO:Al films were characterized by Hall effect and UN visible spectrophotometer measurements, ZnO:Al films had were hexagonal wurtzite structure and dominant c-axis orientation. The R.f power and working pressure for optimum condition to fabricate the transparent conductive films using a PI substrate were 2 mTorr and 100W, respectively. The resistivity of the ZnO:Al films prepared under this condition were $9.6{\times}10^{-4}{\Omega}cm$. The optical transmittance of 400nm thick films at 550nm is ${\sim}85 %$.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1433-1435
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• 1997

ZnO shows the properties of wide conductivity variation, high optical transmittance, and excellent piezoelectricity. Using these properties of ZnO, the material applications were extended to sensors, SAW filters, solar cells, and display devices. This paper investigated transmittance influencing factors for thin film ZnO grown by RF magnetron sputtering. The growth rate and structural investigation were carried out in conjunction with optical transmittance characteristics of thin film ZnO. The glass substrate temperature of $175^{\circ}C$ exhibited a preferential crystallization along (002) orientation. Transmittance of ZnO film deposited at the substrate temperature of $175^{\circ}C$ showed higher than 92%. An active sputter gas was investigated with a variation of $O_2$ partial pressure from 0 to 10% in an Ar atmosphere. ZnO film grown in 100% Ar gas shows that a reduced transmittance of 82% at the short wavelengths and decreased resistivity value. As the partial pressure of $O_2$ gas increased, the optical transmittance was increased above 90% at the short wavelengths, however, resistivity was drastically increased to higher than $10^4{\Omega}$-cm.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.1
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• pp.72-77
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• 2013

The effect of sputtering condition on the structural properties of ZnO thin films grown by RF magnetron sputtering system was investigated for TFT driver circuit. ZnO thin films were grown with ZnO target varying RF power and working pressure. Structural properties were investigated by X-ray diffraction (XRD) and atomic force microscope (AFM). The ZnO thin films have sufficient crystallinity on the 100W RF power. But, the surface roughness of ZnO films was increased as increased RF power. As increased working pressure from 5 mTorr to 15 mTorr, a full width at half maximum (FWHM) of ZnO (002) peak was increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.10
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• pp.909-916
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• 2005

The structural and electrical property of RF magnetron sputtered ZnO thin film have been studied as a function of RF power, substrate temperature, oxygen/argon gas ratio and film thickness at constant sputtering power, sputtering working pressure and target-substrate distance. To analyze a crystallo-graphic properties of the films, $\theta$/2$\theta$ mode X-ray diffraction, SEM, and AFM analyses. C-axis preferred orientation, resistivity and surface roughness highly depended on oxygen/argon gas ratio. The resistivity of ZnO thin film(6000 ${\AA}$) rapidly increased with increasing oxygen ratio and the resistivity value of $9 {\ast} 10^7 {\Omega}cm$ was obtained at a working pressure of 10 mTorr with the same oxygen/argon gas ratio. The surface roughness was also improved with increasing oxygen ratio and the ZnO films deposited with the same oxygen/argon gas ratio showed the excellent roughness value of 28.7 ${\AA}$. With increase of the substrate temperature, The C-axis preferred orientation of ZnO thin film increases and the resistivity decreases due to deviation from the stoichiometric ZnO due to oxygen deficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.12
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• pp.1134-1139
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• 2006

Electrical, optical, and structural properties of indium zinc oxide (IZO) anode films grown by a RF magnetron sputtering were investigated as functions of RF power and working pressure in pure Ar ambient. To investigate electrical, optical and structural properties of IZO anode films, 4-point probe and UV/VIS spectrometry, and X-ray diffraction (XRD) were performed, respectively. A sheet resistance of $15.2{\Omega}/{\square}$, average transmittance above 80 % in visible range, expecially above 85 % in 550 nm, and root mean square roughness of 1.13 nm were obtained from optimized IZO anode films grown in oxygen free ambient. All samples show amorphous structure regardless of RF power and working pressure due to low substrate temperature. In addition, XPS depth profile obtained from IZO/PES exhibits that there is no obvious evidence of interfacial reaction between IZO and PES substrate. Furthermore, current-voltage-luminance of the flexible phosphorescent flexible OLEDs fabricated on IZO anode shows dependence on sheet resistance of the IZO anode. These results indicate that the IZO anode is a promising candidate to substitute conventional ITO anode for high-quality flexible displays.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.857-860
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• 2003

Tin doped indium oxide(ITO) and Al doped zinc oxide(ZnO:Al) films, which are widely used as a transparent conductor in optoelectronic devices such as solar cell, liquid crystal display, plasma display panel, thermal heater, and other sensors, were prepared by using the capacitively coupled DC magnetron sputtering method. The electrical and optical properties of both the ITO and ZnO:Al thin films were investigated as functions of substrate temperature, working gas pressure and deposition time. ITO and ZnO:Al films with the the present experimental conditions of temperature and pressure showed resistivity of $2.36{\times}10^{-4}{\Omega}-cm,\;9.42{\times}10^{-4}{\Omega}-cm$ and transmittance of 86.28%, 90.88% in the wavelength range of the visible spectrum, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.10
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• pp.923-929
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• 2008

On the piezoelectric polymer, PVDF (poly vinylidene fluoride), the transparent conducting oxide (TCO) electrode material thin film was deposited by roll to roll sputtering process mentioned as a mass product-friendly process for display application. The deposition method for ITO Indium Tin Oxides) as our TCO was DC magnetron sputtering optimized for polymer substrate with the low process temperature. As a result, a high transparent and good conductive ITO/PVDF film was prepared. During the process, especially, the gas mixture ratio of Ar and Oxygen was concluded as an important factor for determining the film's physical properties. There were the optimum ranges for process conditions of mixture gas ratio for ITO/PVDF From these results, the doping mechanism between the oxygen atom and the metal element, Indium or Tin was highly influenced by oxygen partial pressure condition during the deposition process at ambient temperature, which gives the conductivity to oxide electrode, as generally accepted. With our studies, the process windows of TCO for display and other application can be expected.