• Journal of the Korean Ceramic Society
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• v.29 no.6
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• pp.431-440
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• 1992

• Journal of the Korean Ceramic Society
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• v.35 no.7
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• pp.685-690
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• 1998

The wetting behavior and the characteristic of spontaneous infiltration of pure Al and Al-(Si)-Mg alloys on {{{{ { {Al }_{ 2} O}_{3 } }} in vacuum argon and nitrogen atmosphere were investigated to find out the spontaneous in-filtration mechanism. The wetting of molten Al and Al alloys on {{{{ { {Al }_{ 2} O}_{3 } }} was only possible in cacuum at-mosphere but the sponataneous infiltration of molten Al-(Si)-Mg alloys was successfully made on {{{{ { {Al }_{ 2} O}_{3 } }} pre-form in nitrogen atmoshpere. The difference of wettability and spontaneous infiltration of molten Al and Al alloys on {{{{ { {Al }_{ 2} O}_{3 } }} were found to be related to formation of the Mg-N compound coated layer on {{{{ { {Al }_{ 2} O}_{3 } }} particles which was believd to increase wettability of molten Al alloys on {{{{ { {Al }_{ 2} O}_{3 }.

• Journal of the Korean institute of surface engineering
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• v.33 no.1
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• pp.3-9
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• 2000

Arc-melted alloys of TiAl-(o.25, 0.5, 1.0at%) Si were isothermally oxidized at 800, 900 and $1000^{\circ}C$ in air for 60hr. It was found that the oxidation resistance of the prepared TiAl-Si alloys was much better than that of pure TiAl, being progressively increasing with an increase in the Si content. This was attributed to the formation of $SiO_2$in addition to ($TiO_2$+$Al_2$$O_3$) oxides which formed in TiAl alloys with and without silicon additions. However, the silica formation within the oxide layer unfortunately accelerated the oxide scale spallations. During oxidation, all the elements in the base alloy diffused outward, whereas oxygen from the atmosphere diffused inward. The oxides were primarily composed of an outer thick $TiO_2$layer, an intermediate diffuse $Al_2$$O_3$layer and an inner $TiO_2$layer. A small amount of $SiO_2$was present all over the oxide scale and some voids were found around the intermediate layer.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.263-266
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• 2000

This paper is focused on the fabrication of reliable Al/$TiO_2-SiO_2$/Mo antifuse, which could operate at low voltage along with the improvement in on/off state properties. Mo metal as the bottom electrode had smooth surface and high melting point, and was being kept as-deposited $SiO_2$film stable. The breakdown voltage of TiO_2-SiO_2$ stacked antifuse was better than that of same-thickness (100 $\AA$) $SiO_2$antifuse because of Ti diffusion in $SiO_2$. The improving breakdown-voltage and on-resistance can be obtained as well as the influence of hillock in the bottom metal is reduced by using double insulator. Low on-resistance (65 $\Omega$) and low programming voltage (9.0 V) can be obtained in these antifuses with 250 $\AA$ double insulator.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.10
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• pp.98-106
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• 1996

A thin film of aluminum for ultra large scale integrated circuits metalization has been deposited on TiN and SiO$_{2}$ substrates by plasma assisted chemical vapor deposition using DMEAA (dimenthylethylamine alane) as a precursor. The effects of plasma on surface topology and growth characteristics were investigated. Thermal CVD Al could not be got continuous films on insulating subsrate such as SiO$_{2}$. However, it was found that Al films could be deposited on SiO$_{2}$ substate without any pretreatments by the hydrogen plasma for pyrolysis of DMEAA. Compared to the thermal CVD, PACVD films showed much better reflectance and resistance on TiN and SiO$_{2}$ substrate. We obtained mirror-like PACVD Al film of 90% reflectance and resistance on TiN and SiO$_{2}$ substrates. We obtained mirror-like PACVD Al film of 90% reflectance on TiN substrate. Excellent conformal step coverage was obtained on submicron contact holes ;by the PACVD blanket deposition.

• Journal of the Korean Ceramic Society
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• v.30 no.8
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• pp.615-622
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• 1993

In order to increase chemical durability of thin films in binary system B2O3-SiO2 and Al2O3-SiO2 on the slide glass by the dip-coating technique from TEOS(Tetraethyl Orthosilicate) and boric acid or aluminum nitrate, phosphoric acid(5~20mol%) was added, respectively. Corrosion of acid and alkali of samples treated with 1N, HCl, NaOH and distilled water at 10$0^{\circ}C$ for 15 minute, were measured IR transmittance and variance of transmittance at visible range. Surface structure of thin film was investigated with SEM and formation of crystal phase according to additiion of phosphoric acid was measrued with XRD. In Al2O3-SiO2 system, change of remarkable characteristic was not obtained at the addition of P2O5 but transmittance of thin film was decreased with addition of P2O5 in B2O3-SiO2 system.

• Journal of the Korean Ceramic Society
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• v.28 no.7
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• pp.561-567
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• 1991

Submicron ${\alpha}-SiC$ powder with $Al_2O_3$ addition was hot-pressed under the controlled heating and pressurizing schedule. $SiO_2$ layer on ${\alpha}-SiC$ powder was effective for the sintering of ${\alpha}-SiC$ powder when $Al_2O_3$ was used as an additive. Applying of pressure under the controlled schedule accelerated the rearrangment of SiC grains, yielding 98% of theoretical density of SiC even at $1900^{\circ}C$. Flexural strength of the specimen containing 2 wt% $Al_2O_3$ was increased as increasing the hot-pressing temperature up to $2050^{\circ}C$ and maximum value was 800 MPa, while the flexural strength of the specimen containing 10 wt% $Al_2O_3$ was decreased as increasing the hot-pressing temperature above $2000^{\circ}C$ due to the formation of continuous grain boundary phase. Fracture toughness of the specimens was in the range of $3.5~4.5\;MNm^{-3/2}$ regardless of the amount of $Al_2O_3$ addition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.12
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• pp.1017-1024
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• 2000

Effect of the microwave dielectric properties and the microstructure on a mole fraction(x=0.1~0.9) of (1-x)Mg$_2$SiO$_4$-xZnAl$_2$O$_4$ ceramics was investigated. When (1-x)Mg$_2$SiO$_4$-xZnAl$_2$O$_4$(x=0.1~0.9) ceramics were sintered at 130$0^{\circ}C$, 135$0^{\circ}C$ and 140$0^{\circ}C$ for 2hr, the microwave dielectric properties were obtained $\varepsilon$r=6.8~8.3, Q.f$_{0}$=36000~77600. On the other hand, the temperature coefficients of resonant frequency($\tau$$_{f}$) were obtained in the properties of -62ppm/$^{\circ}C$ to -49ppm/$^{\circ}C$. In order to adjust the temperature coefficient of resonant frequency($\tau$$_{f}$), CaTiO$_3$was added in (1-x)Mg$_2$SiO$_4$-xZnAl$_2$O$_4$ceramics. 0.7Mg$_2$SiO$_4$-0.2ZnAl$_2$O$_4$-0.1CaTiO$_3$ceramics sintered at 135$0^{\circ}C$ for 2hr showed the excellent microwave dielectric properties of $\varepsilon$r=7.7, Q.f$_{0}$=32000, and $\tau$$_{f}$=-7.9 ppm/$^{\circ}C$.EX>.>.EX>.

• Journal of Welding and Joining
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• v.22 no.5
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• pp.46-52
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• 2004

AlSi-Al$_2$O$_3$ composite layer was prepared by plasma spray on steel substrate. The composite powder for plasma spray was prepared by simple mechanical blending. The wear resistance of the composite layers and matrix aluminum alloy were performed in terms of size distribution of ceramic particles. Friction coefficients of AlSi were decreased with incorporation of $Al_2$O$_3$. The tribological properties of coated layers were affected by the size of incorporated $Al_2$O$_3$ particle. The reinforcement of $Al_2$O$_3$ particle into aluminum alloy matrix decreased the friction coefficient as well as wear loss.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.163-166
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• 2003

The electrothermal simulation of high voltage LIGBT(Lateral Insulated Gate Bipolar Transistor) in thin Silicon on insulator (SOI) and Silicon on sapphire (SOS) for thermal conductivity and sink is performed by means of MEDICI. The finite element simulations demonstrate that the thermal conductivity of the buried oxide is an important parameter for the modeling of the thermal behavior of silicon-on-insulator (SOI) devices. In this paper, using for SOI LIGBT, we simulated electrothermal for device that insulator layer with $SiO_2\;and\;Al_2O_3$ at before and after latch up to measured the thermal conductivity and temperature distribution of whole device and verified that SOI LIGBT with $Al_2O_3$ insulator had good thermal conductivity and reliability