• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.136-137
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• 2007

Wear resistant TiAlN thin film has been widely deposited on the surface of cutting and forming tools by using Arc Ion Plating. TiAlN films are deposited by the processes designed by the Taguchi L18 experimental design. The L18 experimental design is applied to achieve surface properties and adhesion. The deposition parameters are working pressure, substrate temperature, bias voltage, arc power and pre-sputtering bias voltage and time. The most influential parameters on surface properties and adhesion are substrate bias voltage, working nitrogen pressure and arc power. The optimal coating processes are obtained for surface properties and adhesion.

• Proceedings of the Korean Magnestics Society Conference
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• 1991.05a
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• pp.73-74
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• 1991

The films with ferromagnetic fine particles dispersed in nonmagnetic matrix, such as $Fe-Al_2O_3$ and Fe-Cu have been studied for use of magnetic recording medium, optically device and sensor. Their magnetic properties depend strongly on structural parameter such as size and volume fraction of ferromagnetic particles. Fe-Cr-Ni alloy sputtered films also have microstructure with ferromagnetic -- b.c.c phase and nonmagnetic f.c.c phase grains. Magnetic properties of these films depend strongly on such a unique structure. These are depend on the ratio in volume of ferromagnetic particles to nonmagnetic ones $V_F/V_N$, the saturation magnetization Ms increased with increase of $V_F/V_N$. The coercivity Hc of the as-deposited films took maximum value of about 200 Oe at adequate $V_F/V_N$ and then Ms and Squareness S were 500 emu/cc and 0.5, respectively.(omitted)

• Proceedings of the Korean Vacuum Society Conference
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• 1993.07a
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• pp.87-88
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• 1993

• Proceedings of the Korean Ceranic Society Conference
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• 2000.10a
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• pp.193.1-193
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• 2000

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.11a
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• pp.144-145
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• 1996

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.122-123
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• 2007

Bias voltage를 달리하여 cathodic arc plasma 방법으로 Si 기판 위에 성장시킨 TiCrAlSiN 코팅막의 미세구조를 투과전자현미경으로 관찰하였다. -200 V에서 0 V로 bias voltage가 변화함에 따라 'nano-multilayered' 구조가 무너지면서 '주상형(columnar)'구조로 코팅막의 미세구조가 변함을 알 수 있었고, EDS line scan을 통해 multilayer의 화학적 조성 변화를 확인하였다.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.53-58
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• 1997

It is well known that the equiatomic FeAl alloy crystallizes in a paramagnetic CsCl structure and is very stable in a wide temperature range owing to a significant charge transfer from Al to Fe. A presence of structural defects normally enhances the magnetic and magneto-optical properties of this alloy. In this study spin-resolved photoemission and magnetic circular dichroism (MCD) were carried out on both ordered and disordered $Fe_{0.52}Al_{0.48}$ alloy films. The disordered state in the alloy films was obtained by a vapor quenching deposition on cooled substrates. It is shown that the order-disorder transition in the Fe0.52Al0.48 alloy films leads to a significant change in the spin polarization. Form the MCD results the orbital and spin magnetic moments of the constituent atoms are obtained. According to the sum rule the spin and orbital magnetic moments of Fe in the disordered FeAl film are $\mu\frac{SR}{spin}=0.8\mu_B$ and $\mu\frac{SR}{orb}=0.14\mu_B$ respectively. The spin magnetic moment is also evaluated to be $\mu\frac{BR}{spin}=0.77\mu_B$ by the branching ration method employing a photon polarization of 90%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.775-779
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• 2006

In this study, sputtered $Al_2O_3$ thin films were evaluated as a passivation layer in the process of InGaN-based blue LEDs in order to improve the brightness of LED lamps. In terms of packaged LED lamps, lamps with $Al_2O_3$ passivation layer emanated higher brightness than those with $SiO_2$ passivation layer, and LED lamps with 90 nm $Al_2O_3$ passivation layer were the brightest among four kinds of lamps. Although lamps with $Al_2O_3$ passivation had a slight increase in operating voltage, their brightness was improved about 13.6 % compare to the lamps made of conventional LEDs without the changes of emitting wavelength.

• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1314-1319
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• 1998

Electronic structures and properties of the organometallic precursors [Me2AlNHR]2 (R =Me, iPr, and tBu) have been calculated by the semiempirical (ASED-MO, MNDO, AM1 and PM3) methods. Optimized structures obtained from the MNDO, AM1, and PM3 calculations indicate that the N-C bond lengths are considerably affected by the change of the R groups bonded to nitrogen, but the bond lengths of the Al-N and Al-C bonds are little affected. This result is useful in explaining the experimental results for the elimination of the R groups bonded to nitrogen, and could serve as a guide in designing an optimum precursor for the AlN thin film formation.

• Journal of the Korean institute of surface engineering
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• v.47 no.4
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• pp.174-180
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• 2014

In this study, TiAlSiN coatings have been successfully synthesized on stainless steel and tungsten carbide substrate by a hybrid coating method employing a cathodic arc and a magnetron sputtering source. TiAl and Si target were vaporized with the cathodic arc source and the magnetron sputtering source, respectively. Process gas was the mixture of nitrogen and argon gas. With the increase of Si content, the crystallinity and the grain size of TiAlSiN film was decreased. At the Si content of more than 8 at.%, grain size of TiAlSiN was saturated at around 2 nm. The hardness value of the TiAlSiN film increased with incorporation of Si, and had the maximum value of ~ 3,233 Hv at the Si content of 9.2 at.%. The oxidation resistance of TiAlSiN film was enhanced with the increase of Si content.