• Journal of the Korean institute of surface engineering
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• v.48 no.2
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• pp.43-49
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• 2015

This study reports a fabrication of $TiO_2$ on the surface of dental implants by pulsed d.c. magnetron sputtering from a Ti target. A systematic investigation on the microstructure and mechanical properties of $TiO_2$ films was carried out with the variation of $O_2$ contents and substrate temperatures. The effects of deposition parameters on the fabricated structures were investigated by X-ray diffraction (XRD) technique and field emission scanning electron microscope (FE-SEM). Hydrophilic properties were evaluated by measuring water contact angles on the film surface. With increasing $O_2$ contents up to 40%, surface roughness of $TiO_2$ film increased while relatively smooth surface was obtained with 50% $O_2$ contents. Surface roughness and adhesion strength both increased as substrate temperature increased up to $200^{\circ}C$. From these results, hydrophilic and adhesive properties of the present $TiO_2$ films synthesized with 40% $O_2$ at $200^{\circ}C$ are regarded to be suitable for bio-compatible applications.

• Journal of the Korean Magnetics Society
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• v.12 no.2
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• pp.64-67
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• 2002

IrMn pinned spin valve (SV) films with stacks of Ta/NiFe/IrMn/CoFe/Cu/CoFe/NiFe/Ta were prepared by dc sputtering onto thermally oxidized Si (111) substrates at room temperature under a magnetic field of about 100 Oe. The annealing cycle number and temperature dependence of exchange coupling field (H$_{ex}$), magnetoresistance (MR) ratio, and coercivity (H$_{c}$) were investigated. By optimizing the process of deposition and post thermal annealing condition, we obtained the IrMn based SV films with MR ratio of 3.6%, H$_{ex}$ of 1180 Oe for the pinned layer. The H$_{ex}$ is stabilized after the second annealing cycle and it is thought that this SV reveals high thermal stability. The H$_{ex}$ maintained its strength of 600 Oe in operation up to 24$0^{\circ}C$ and decreased monotonically to zero at 27$0^{\circ}C$.

• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.81-86
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• 1997

Platinum thin films were deposited on $SiO_{2}/Si$ and $Al_{2}O_{3}$ substrates by DC magnetron sputtering for RTD (resistance thermometer devices) temperature sensors. The resistivity and sheet resistivity of these films were decreased with increasing the annealing temperature and time. We made Pt resistance pattern on $Al_{2}O_{3}$ substrate by lift-off method and fabricated Pt-RTD temperature sensors by using W-wire, silver epoxy and SOG(spin-on-glass). In the temperature range of $25{\sim}400^{\circ}C$, we investigated TCR(temperature coefficient of resistance) and resistance ratio of Pt-RTD temperature sensors. TCR values were increased with increasing the annealing temperature, time and the thickness of Pt thin films. Resistance values were varied linearly within the range of measurement temperature. At annealing temperature of $1000^{\circ}C$, time of 240min and thin film thickness of $1{\mu}m$, we obtained TCR value of $3825ppm/^{\circ}C$ close to the Pt bulk value.

• Journal of the Korean Magnetics Society
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• v.27 no.3
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• pp.82-86
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• 2017

The IrMn based GMR-SV films with three different buffer layers were prepared on Corning glass by using ion beam deposition and DC magnetron sputtering method. The major and minor magnetoresistance curves for three different buffer layers beneath the structure of NiFe(15 nm)/CoFe(5 nm)/Cu(2.5 nm)/CoFe(5 nm)/NiFe(7 nm)/IrMn(10 nm)/Ta(5 nm) at room temperature have shown different magnetoresistance properties. When the samples were annealed at $250^{\circ}C$ in vacuum, the magnetoresistance ratio, the coercivity of pinned ferromagnetic layer, and the interlayer coupling field of free ferromagnetic layer were enhanced while the exchange bias coupling field did not show noticeable changes.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.233-236
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• 2000

The structural, electrical and chemical characteristics of Al alloy thin film with low impurity concentrations AlW deposited by using dc magnetron sputtering deposition are investigated for the applications as data bus line in the TFT-LCD panel. The deposited thin films show the decrease of resistivity and the increase of grain size after the RTA at $300^{\circ}C$ for 20 min.. Moreover, the resistivity of AlW does not show appreciable grain size dependence after RTA. It is concluded that the decrease of resistivity after RTA is due to the increase of grain size. The annealed AlW is found to be hillock free. And for investigating chemical attack in TFT-LCD etching processing the electric potential of AlW alloy for Ag/AgCl were investigated by cyclic voltammetry. When W wt.% of AlW alloy was higher than about 3%, the electric potential of AlW was more positive than ITO's. Therefore AlW alloy thin film can be propose to use for data bus line.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.420-423
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• 2003

[ $TiO_2$ ] thin films were fabricated by DC magnetron sputtering system at by controlling deposition times, ratios of $Ar:O_2$ partial presser ratio and substrate conditions. And the surface, cross-section morphology, microstructure, and composition ratio of the films were analyzed by FE-SEM, TEM and XPS. Besides, the optical absorption and transmittance of the $TiO_2$ films were measured by a UV-VIS-NIR Spectrophotometer, and photocatalytic properties were studied by G C Analyzer & Data Analysis system. As the result, when $TiO_2$ thin film was made at deposition time of 120[min] and $Ar:O_2$ ratio of 60:40, the best structural and optical properties among many thin films could be accepted. The best results of properties were as follows: thickness; $360{\sim}370[nm]$, grain size; 40[m], gap between two peak binding energy, $5.8{\pm}0.05[eV]$ ($2p_{3/2}$ peak and $2p_{1/2}$ peak of Ti was show at $458.3{\pm}0.05[eV]$ and $464.1{\pm}0.05[eV]$ respectively), binding energy; $530{\pm}0.05\;[eV]$, opticalenergy band gap; 3.4[eV].

• Journal of the Korean Ceramic Society
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• v.39 no.10
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• pp.928-934
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• 2002

Gallium doped Zinc Oxide(GZO) films were deposited by dc magnetron sputtering using a GZO ceramic target at various conditions such as substrate temperature (RT, 400), residual water pressure ($P_{H_2O}$; 1.61${\times}10^{-4}∼2.2{\times}10^{-3}$ Pa), introduction of $H_2$ gas (8.5%) and different magnetic field strengths(250, 1000G). GZO films deposited without substrate heating showed clear degradation in film crystallinity and electrical properties with increasing $P_{H_2O}$. The resistivity increased from 3.0${\times}10^{-3}$ to 3.1${\times}10^{-2}{\Omega}㎝$ and the grain size of the films decreased from 24 to 3 nm when PH2O was increased from 1.61${\times}10^{-4}$ to 2.2${\times}10^{-3}$ Pa. However, degradation in electrical properties with increasing $P_{H_2O}$ was not observed for the films deposited with introduction of 8.5% $H_2$. When magnetic field strength of the cathode increased from 250G to 1000G, crystallinity and electrical properties of GZO films improved remarkably about all the $P_{H_2O}$. This result could be attributed to the decrease in film damage caused by the decrease in plasma impedance.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.2
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• pp.297-302
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• 2019

In this study, we deposited ITO thin films on buffer layer of $Nb_2O_5(8nm)/SiO_2(45nm)$ using DC magnetron sputtering method and investigated its electrical and optical properties with various DC powers(100~400 W). The surface of the ITO thin film was observed by AFM. All thin films had defected free surface such as pinholes and cracks. The thin film deposited at DC power of 200 W exhibited the smallest surface roughness of 1.431nm. As a result of electrical and optical measurements, the ITO thin film deposited at DC power of 200 W which showed the lowest resistivity of $3.03{\times}10^{-4}{\Omega}-cm$. The average transmittance in the visible light region(400 to 800 nm) and the transmittance at the wavelength of 550nm were found to be 85.8% and 87.1%, respectively. The chromaticity(b*) was also a relatively good value as 2.13. The figure of merit obtained from the sheet resistance of the ITO thin film, the average transmittance in the visible light region and the transmittance at the wavelength of 550nm were the best values of $2.50{\times}10^{-3}{\Omega}^{-1}$ and $2.90{\times}10^{-3}{\Omega}^{-1}$ at a DC power of 200W, respectively.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.400-406
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• 1997

The electrical and physical characteristics of aluminum oxide and Pt thin films on it, deposited by reactive sputtering and DC magnetron sputtering, respectively, were analyzed with increasing annealing temperature($400{\sim}800^{\circ}C$) by four point probe, SEM and XRD. Under $600^{\circ}C$ of annealing temperature, aluminum oxide had the properties of improving Pt adhesion to $SiO_{2}$ and insulation without chemical reaction to Pt thin films and the resistivity of Pt thin films was improved. But these properties of aluminum oxide and Pt thin films on it were degraded over $700^{\circ}C$ of annealing temperature because aluminum oxide was changed into metal aluminum and then reacted to Pt thin films deposited on it. The thermal characteristics of Pt micro heater were analyzed with Pt-RTD integrated on the same substrate. In the analysis of properties of Pt micro heater, active area was smaller size, Pt micro heater had better thermal characteristics. The temperature of Pt micro heater with active area, $200{\mu}m{\times}200{\mu}m$ was up to $400^{\circ}C$ with 1.5watts of the heating power.

• Journal of the Korean Vacuum Society
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• v.22 no.3
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• pp.126-130
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• 2013

The sodium (Na) and moisture ($H_2O$) gettering phenomena were measured and analyzed in PSG/$SiO_2$ passivated Al-1%Si thin film interconnections. PSG/$SiO_2$ passivation and Al-1%Si thin films were deposited by using APCVD (atmosphere pressure chemical vapor deposition) and DC magnetron sputter techniques, respectively. SIMS (secondary ion mass spectrometry) depth profiling analysis was used to determine the distribution of sodium and moisture throughout the PSG/$SiO_2$ passivated Al-1%Si thin film interconnections. Both sodium and moisture peaks were observed strongly at the interfaces between layers rather than within the Al-1%Si thin film interconnections. Sodium peaks were observed at the interface between PSG and $SiO_2$ passivations, while moisture peaks were not observed.