• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.7
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• pp.527-534
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• 1998

Thin film deposition of InN, which is a less-studied III-nitride compound semiconductor because of the difficulty if crystal growth, was performed by rf reactive sputtering method using In target and $N_2$reactive gas. The structrual, electrical, and optical properties of the produced films were measured and disussed according to the sputtering parameters such as deposition pressure, rf power, and substrate temperature. From the result of deposition pressure, rf power, and substrate temperature, we could obtain optimal conditions of 5m Torr, 60W, $60^{\circ}C$ for preparing InN thin film with high crystallinity, low carrier concentration, and high Hall mobility. The carrier concentration, Hall mobility, and optical bandgap of the fabricated InN thin films at optimal condition were $6.242\times10^{18}cm^{-3}, 212.526cm^2/V\cdot$ｓ, and 1.912eV, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.743-745
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• 2002

Pyroelectric and dielectric properties of modified PZT thin film and bulk ceramics were studied. In case of bulk specimens were prepared by conventional ceramic process and thin films with same composition and (111) preferred orientation were prepared by the sol-gel process. Their crystal structure, pyroelectric and dielectric properties were investigated after poling at $150^{\circ}C$ for 30 min for bulk ceramics and no poling treatment, respectively. Dielectric constants and losses of bulk and thin film were 600, 875 and 0.028, 0.025, respectively. Pyroelectric coefficients obtained were $50nC/cm^2K$ and $30nC/cm^2K$, respectively.

• Korean Journal of Materials Research
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• v.10 no.1
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• pp.21-28
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• 2000

Refractory metals, W and Ti, and their nitrides, $W_2N$ and TiN, were investigated for using as an ohmic contact material with SiC single crystalline thin films. The possibility of nitride materials for using as a stable ohmic contact material of SiC at high temperatures was examined by considering the thermal stability depending on the heat treatment temperature, their electrical properties and protective behavior from the interdiffusion. W contact with SiC thin films, deposited by using new organosilicon precursor, bis-trimethylsilylmethane, showed the lowest resistivity, $2.17{\times}10^{-5}$Ω$\textrm{cm}^2$. On the other hand, Ti-based contact materials showed higher contact resistivity than W-based ones. The oxidation of contact materials was restricted by applying Pt thin films on those electrodes. Nitride electrodes had rather stable electrical properties and better protective behavior from interdiffusion than metal electrodes.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.25-29
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• 2003

Nickel-ferrite $Ni_xFe_{3-x}O_4$ thin films with several composition for Ni on glass substrate was prepared by ferrite plating method in order to make sunglass which cut off ultraviolet and shield electromagnetic field. It has single phase of polycrystalline spinel structure and has gloss as mirror and has high hardness which is no scratch while scraping by using nail. The transmittance of nickel-ferrite thin film is lowered to zero below 400 nm manifestly. And it shows that the nickel-ferrite thin film in nickel composition rate x = 0.09 was most cut oil ultraviolet when compared with goods of other company in the cut off effect of ultraviolet. Therefore, sunglasses coated with $Ni_xFe_{3-x}O_4$ thin film can be used in removing ultraviolet and electromagnetic field.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.69-76
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• 1997

P-type ($Bi_{0.5}Sb_{1.5}Te_3$) and n-type ($Bi_2Te_{2.4} Se_{0.6}$) thermoelectric thin film were deposited on glass and Teflon substrates by the flash evaporation technique. The changes in thermoelectric properties, such as Seebeck coefficient, electrical conductivity, carrier concentration, carrier mobility, thermal conductivity, and figure of merit, were investigated as a function of film thickness and annealing condition. Figures of merit of the thin films annealed at 473 K for 1 hour were improved to be $1.3{\times}10^{-3}K^{-1}$ for p-type and $0.3{\times}10^{-3}K^{-1}$ for n-type, and they were almost independent of film thickness. Temperature sensors were fabricated from the thin films having the above mentioned properties. And thermo-emf, sensitivity, and time constant of the sensors were measured to evaluate their characteristics for temperature sensors. Thin film sensors deposited on Teflon substrates showed better performance than those on glass substrates, and their sensitivity and time constant were 2.91 V/W and 28.2 sec respectively for the sensor of leg width 1 mm$\times$length 16 mm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.160-161
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• 2005

The $(Sr_{1-x}Ca_x)TiO_3$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method with substitutional contents of Ca. The optimum conditions of RF power and $Ar/O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin film was about 18.75$[{\AA}/min]$. The dielectric constant was increased with increasing the substitutional contents of Ca, while it was decreased if the substitutional contents of Ca exceeded over 15[mol%]. All SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

• Journal of the Korean Vacuum Society
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• v.10 no.2
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• pp.189-193
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• 2001

We have characterized physical and electrical properties of W-TiN stacked gate electrode structure with TiN as a diffusion barrier of fluorine. As the $N_2/Ar$ gas ratio increased during sputter deposition, TiN thin films became N-rich, and the resistivity of the films increased. However, the resistivity of W-TiN stacked gate reduced as a result of the crystallization of tungsten with the increase of $N_2/Ar$ gas ratio. On the other hand, tungsten in W-TiN stacked gate structure have the (100)-oriented crystalline structure although TiN films were subjected to annealing at high temperature (600~$800^{\circ}C$). Leakage currents of W-TiN gate MOS capacitors were less than $10^{-7}\textrm{/Acm}^2$ and also were lowered by the order of 2 compared with those of pure W gate electrode.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.367-367
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• 2008

Aluminum nitride (AlN) thin films have been deposited on Si substrate by using reactive RF magnetron sputtering method in a gas mixture of Ar and $N_2$ at different $N_2$ concentration. It was found that $N_2$ concentration was varied in the range up to 20-100%, highly c-axis oriented film can be obtained at 50% $N_2$ with full width at half maximum (FWHM) $4.5^{\circ}$. Decrease in surface roughness from 7.5 nm to 4.6 nm found to be associated with decrease in grain size, with $N_2$ concentration; however, the AlN film fabricated at 20% $N_2$ exhibited a granular type of structure with non-uniform grains. The absorption peak was observed around 675 $cm^{-1}$ in fourier transform infrared spectroscopy (FTIR). It is concluded that the AlN film deposited at $N_2$ concentration of 50% exhibited the most desirable properties for the application of high-frequency surface acoustic devices.

• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.63-63
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• 2009

• Journal of the Korean Society for Heat Treatment
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• v.5 no.2
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• pp.95-102
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• 1992

In this study, we tried to describe the quantitative model of TiN film structure which was deposited by PECVD process. The macro-grain growth behavior was studied at the various deposition pressures and times. As a result, It was confirmed that TiN films had the typical Zone 1 structure, and macro-columnar grains were, without reference to the deposition pressure, grown ballistic type by the growth-death competition following the equation, $Y=aX^2$, approximately obtained by regression analysis. Also, the thickness and the crystallization of TiN thin films were increased, the chlorine contents were decreased according to the decreasing of deposition pressure.