• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.3
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• pp.204-208
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• 2012

$TiO_2$ ($Ti_{1-x}Nb_xO_2$, x= 0.04~0.06) transparent conducting oxide film was fabricated by RF magnetron sputtering process and their electrical, optical, stability properties were studied. When the Nb 4 at% sputtering target was used with RF power 120 W, pressure 8 mTorr, post-annealing temperature $600^{\circ}C$, the resistivity of TNO film was $4{\times}10^{-4}\;{\Omega}-cm$. The optical transmittance in the visible wavelength was ca. 86%. TNO films require heat treatment during or after the deposition process. When the film was deposited at room temperature and post-annealed at $600^{\circ}C$, the lowest resistivity was obtained. When the TNO film was exposed to high temperature and humidity, the resistivity of the film was rather decreased. The stability to temperature and humidity implies that the TNO film could be a appropriate candidate for In-free, ZnO-free transparent conducting oxide materials.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.374-378
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• 2010

The effects of $O_2$ plasma pretreatment on the properties of Ga-doped ZnO films on polyimide substrate were studied. GZO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion between the polyimide substrate and the GZO film, $O_2$ plasma pretreatment process was used prior to GZO sputtering. As the RF power and the treatment time increased, the crystallinity increased and the contact angle decreased significantly. When the RF power was 100 W and the treatment time was 120 sec, the resistivity of GZO films on the polyimide substrate was $1.90{\times}10^{-3}{\Omega}-cm$.

• Journal of the Korean institute of surface engineering
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• v.38 no.5
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• pp.188-192
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• 2005

Indium zinc oxide (IZO) thin films were deposited on glass substrate by dc magnetron sputtering. The effects of oxygen flow rate and deposition temperature on electrical and optical properties of the films were investigated. With addition of small amount of oxygen gas, the characteristic properties of amorphous IZO films were improved and the specific resistivity was about $4.8{\times}10^{-4}\Omega{\cdot}cm$. Change of structural properties according to the deposition temperature was observed with XRD, SEM, and AFM. Films deposited above $300^{\circ}C$ were found to be polycrystalline. Surface roughness of the films was increased due to the formation of grains on the surface. Electrical conductivity became deteriorated for polycrystalline IZO films. Consequently, high quality IZO films could be prepared by do sputtering with $O_{2}/Ar{\simeq}0.03$ and deposition temperature in range of $150\~200^{\circ}C$; a specific resistivity of $3.4{\times}10^{-4}{\Omega}{\cdot}cm$, an optical transmission over $90\%$ at wavelength of 550 nm, and a rms value of surface roughness about $3{\AA}$.

• Journal of the Korean institute of surface engineering
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• v.35 no.6
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• pp.415-421
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• 2002

Ti-Si-N coating layers were codeposited on silicon wafer substrates by a DC reactive magnetron sputtering technique using separate titanium and silicon targets in $N_2$/Ar gas mixtures. The oxidation behavior of Ti-Si-N coating layers containing 4.0 at.%, 10.0 at.%, and 27.3 at.% Si was investigated at temperatures ranging from 600 to $960^{\circ}C$. The coating layers containing 4.0 at.% Si became fast oxidized from $600^{\circ}C$ while the coating layers containing 10.0 at.% Si had oxidation resistance up to $800^{\circ}C$. It was concluded that an increase in Si content to a level of 10.0 at.% led to the formation of finer TiN grains and a uniformly distributed amorphous Si3N4 phase along grain boundaries, which acted as efficient diffusion barriers against oxidation. However, the coating layers containing 27.3 at.% Si showed relatively low oxidation resistance compared with those containing 10.0 at.% Si. This phenomenon would be explained by the existence of free Si which was not nitrified in the coating layers containing 27.3 at.% Si.

• Journal of the Korean institute of surface engineering
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• v.42 no.3
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• pp.128-132
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• 2009

Transparent conducting thin films of indium tin oxide(ITO) co-sputtered with aluminum-doped zinc oxide(AZO) were deposited on glass substrate by dual magnetron sputtering. It was found that the electrical properties and structural characteristics of the films are significantly changed according to the sputtering power of the AZO target. The IAZTO film prepared with D.C power of ITO at 100 W and R.F power of AZO at 50 W shows an electrical resistivity of $4.6{\times}10^{-4}{\Omega}{\cdot}cm$ and a sheet resistance of $30{\Omega}/{\square}$ (for 150 nm thick). Besides of the improvement of the electrical properties, compared to the ITO films deposited at the same process conditions, the IAZTO films have very smooth surface, which is due to the amorphous nature of the films. However, the electrical conductivity of the IAZTO films was found to be deteriorated along with the crystallization in case of the high temperature deposition (above $310^{\circ}C$). In this work, high quality amorphous transparent conductive oxide layers could be obtained by mixing AZO with ITO, indicating possible use of IAZTO films as the transparent electrodes in OLED and flexible display devices.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.1
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• pp.19-24
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• 2010

The effects of $O_2$ plasma pretreatment on the properties of Ga-doped ZnO films on PET substrate were studied. GZO films were fabricated by RF magnetron sputtering process. To improve surface energy and adhesion between the PET substrate and the GZO film, $O_2$ plasma pretreatment process was used prior to GZO sputtering. As the RF power and the treatment time increased, the crystallinity increased and the contact angle decreased significantly. When the RF power was 100 W and the treatment time was 600 sec in $O_2$ plasma pretreatment process, the resistivity of GZO films on the PET substrate was $1.90{\times}10^{-3}{\Omega}-cm$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.448-449
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• 2006

For the possible applicative pearl pigment, multi-layered $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ thin film was deposited on glass substrate by using sputtering method. $TiO_2$ and Al or Cr was selected as a possible high and low refraction materials at the film interface respectively. Optical properties including color effect were systematically studied in terms of different film thickness and film layers by using spectrometer. In order to expect the experimental results, the simulation program, the Essential Macleod Program(EMP) was adopted and compared with the experimental data. The film consisting of $TiO_2/Al/TiO_2$, $TiO_2/Cr/TiO_2$ layers show the wavelength range of 430 - 760nm, typically color ranges between bluish purple and red. It was confirmed that this experimental result was quite well matched with the experimental one.

• Journal of the Korean Ceramic Society
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• v.42 no.1
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• pp.28-32
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• 2005

The optical properties and intrinsic stress of $Ta_{2}O_{5}$ thin films deposited by Dual ion-Beam Sputtering: (DIBS) and Single ion-Beam Sputtering (SIBS) were studied as a function of the substrate temperature and assist ion beam voltage. The refractive index showed the maximum value (n = 2.144) at $150^{circ}C$ in the SIBS process. When the substrate temperature has above $150^{circ}C$ in the SIBS process the refractive index decreased. In the DIBS process, the increase of the substrate temperature affected the increase of the refractive index at a maximum value (n = 2.1117, at $200^{circ}C$). The low temperature process $(<100^{circ}C)$ can greatly reduce residual stress with the assist ion gun, but the high temperature process was unaffected. As the assist ion beam voltage increase from 250 to 350 V the refractive index increased to 2.185. However, the refractive index was decreased at the range of 350-650 V, As the assist ion beam voltage increased, the stress of the deposited film decreased to 0.1834 GPa at 650 V.

• Tribology and Lubricants
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• v.20 no.5
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• pp.237-244
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• 2004

Micro/nano tribological characteristics of PTFE coating films were experimentally studied. PTFE (polytetrafluoroethylene) modified polyethylene and low molecular weight PTFE were used as a coating materials. These films were deposited on Si-wafer (100) by IBAD (ion beam assisted deposition) method. The Ar ion beam sputtering was performed to change the surface topography of films using a hollow cathode ion gun under different Ar ion dose conditions in a vacuum chamber. Micro/nano tribological characteristics, water wetting angles and roughness were measured with a micro tribotester, SPM (scanning probe microscope), contact anglemeter and profilometer, respectively. The durability of the films were measured with macro tribotester. Results showed that the PTFE coating surfaces were converted to hydrophobic. The water contact angle of coated surfaces and surface roughness increased with the coating thickness. Adhesion and friction in micro and nano scale were governed by magnitude of normal load in soft material such as PTFE films. As the increase of sputtering time on low molecular weight PTFE films, the surface roughness was increased and nano adhesion and friction were decreased. The nano tribological characteristics of surfaces are mainly improved by chemical modification such as PTFE coating and given a synergy effect by the physical modification such as topographic modification.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.322-327
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• 2006

CdS films have been prepared on polycarbonate, polyethylene terephthalate, and Coming 7059 substrates by r.f magnetron sputtering technique at room temperature. A comparison of the properties of the films deposited on polymer and glass substrates was performed. In addition, the influence of the sputter power on the structural and optical properties of these films was evaluated. The XRD measurements revealed that CdS films were polycrystalline and retained the mixed structure of hexagonal wurtzite and cubic phase, regardless of substrate types. As the sputter power was increased from 75 to 150 Watt, the structure of CdS films was converted from the mixed of hexagonal and cubic phase to hexagonal phase. The morphology of CdS films is found to be continuous and dense. Also, the grain of CdS films is larger with increasing the sputter power. The average transmittance exceeded 80 % in the visible spectrum for all films and decreases slightly with the sputter power.