• Journal of Information Display
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• 제13권3호
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• pp.107-111
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• 2012

An almost pure phase of $Ba_3Si_6O_{12}N_2$ doped with $Eu^{2+}$ was successfully synthesized through the ammonia nitridation of an oxide precursor prepared through an aqueous-solution method, using propylene- glycol-modified silane. The emission peak intensity of the obtained $Ba_3Si_6O_{12}N_2:Eu^{2+}$ was -2.2 times higher than that of the sample prepared through a solid-state reaction method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.542-545
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• 1987

THE ELECTRICAL CHARACTERISTICS Of RAPID THERMAL OXIDES AND NITRIDED OXIDES HAVE BEEN INVESTIGATED. R.T.OXIDE FILMS HAVE BEEN PREPARED BY ONLY R.T. OXIDATION OR R.T.OXIDATION AND SUBSEQUENT R.T.ANNEAL. NITRIDED OXIDE FILMS HAVE BEEN PREPARED BY R.T.OXIDATION AND SUBSEQUENT R.T.NITRIDATION.AND CONVENTIONAL OXIDES ALSO HAVE BEEN PREPARED TO COMPARE WITH R.T.P OXIDES. R.T.ANNEALED OXIDES SHOW EXCELLENT BREAKDOWN FIELD. LEAKAGE CURRENT AND TDDB CHARACTERISTICS. ALSO, CAPACITANCE Of R.T NITRIDED OXIDES ARE SUPERIOR BY 10% TO CONVENTIONAL OXIDES, BUT TDDB CHARACTERISTIC ARE POORER THAN OXIDE FILMS.

• 한국분말재료학회지
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• 제15권6호
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• pp.496-502
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• 2008

Aluminum nitride (AlN) powders were prepared by the chemical vapor synthesis (CVS) process in the $AlCl_{3}-NH_{3}-N_{2}$ system. Aluminum chloride ($AlCl_3$) as the starting material was gasified in the heating chamber of $300^{\circ}C$. Aluminum chloride gas transported to the furnace in $NH_{3}-N_{2}$ atmosphere at the gas flow rate of 200-400ml/min. For samples synthesized between 700 and $1200^{\circ}C$, the XRD peaks corresponding to AlN were comparatively sharp and also showed an improvement of crystallinity with increasing the reaction temperature. In additions, the average particle size of the AlN powders decreased from 250 to 40 nm, as the reaction temperature increased.

• 한국세라믹학회지
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• 제53권6호
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• pp.622-627
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• 2016

The effects of the debinding atmosphere on the properties of sintered reaction-bonded $Si_3N_4$ (SRBSN) ceramics prepared by tape casting method were investigated. Si green tape was produced from Si slurry of Si powder, using 11.5 wt% polyvinyl butyral as the organic binder and 35 wt% dioctyl phthalate as the plasticizer. The debinding process was conducted in air and $N_2$ atmospheres at $400^{\circ}C$ for 4 h. The nitridation process of the debinded Si specimens was performed at $1450^{\circ}C$, followed by sintering at $1850^{\circ}C$ and 20 MPa. The results revealed that the debinding atmosphere had a significant effect on $Si_3N_4$ densification and thermal conductivity. Owing to the higher sintered density and larger grain size, the thermal conductivity of $Si_3N_4$ specimens debinded in air was higher than that of the samples debinded in $N_2$. Thus, debinding in air could be suitable for the manufacture of high-performance SRBSN substrates by tape casting.

• Journal of Magnetics
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• 제9권1호
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• pp.17-22
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• 2004

We studied the magnetotransport properties of tunnel junctions with AlO and AlN barriers fabricated using microwave-excited plasma. The plasma nitridation process provided wider controllability than the plasma oxidization for the formation of MTJs with ultra-thin insulating layer, because of the slow nitriding rate of metal Al layers, comparing with the oxidizing rate of them. High tunnel magnetoresistance (TMR) ratios of 49 and 44% with respective resistance-area product $(R{\times}A) of 3 {\times} 10^4 and 6 {\times} 10^3 {\Omega}{\mu}m^2$ were obtained in the Co-Fe/Al-N/Co-Fe MTJs. We conclude that AlN is a hopeful barrier material to realize MTJs with high TMR ratio and low $R{\times}A$ for high performance MRAM cells. In addition, in order to clarify the annealing temperature dependence of TMR, the local transport properties were measured for Ta $50{\AA} /Cu 200 {\AA}/Ta 50 {\AA}/Ni_{76}Fe_{24} 20 {\AA}/Cu 50 {\AA}/Mn_{75}Ir_{25} 100 {\AA}/Co_{71}Fe_{29} 40 {\AA}/Al-O$ junction with $d_{Al}= 8 {\AA} and P_{O2}{\times}t_{0X}/ = 8.4 {\times} 10^4$ at various temperatures. The current histogram statistically calculated from the electrical current image was well in accord with the fitting result considering the Gaussian distribution and Fowler-Nordheim equation. After annealing at $340^{\circ}C$, where the TMR ratio of the corresponding MTJ had the maximum value of 44%, the average barrier height increased to 1.12 eV and its standard deviation decreased to 0.1 eV. The increase of TMR ratio after annealing could be well explained by the enhancement of the average barrier height and the reduction of its fluctuation.

• 한국전기전자재료학회논문지
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• 제15권7호
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• pp.576-582
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• 2002

Nonvolatile semiconductor memory devices with reoxidized nitrided oxide(RONO) gate dielectrics were fabricated, and nitrogen distribution and bonding species which contribute to memory characteristics were analyzed. Also, memory characteristics of devices depending on the anneal temperatures were investigated. The devices were fabricated by retrograde twin well CMOS processes with $0.35\mu m$ design rule. The processes could be simple by in-situ process in growing dielectric. The nitrogen distribution and bonding states of gate dielectrics were investigated by Dynamic Secondary Ion Mass Spectrometry(D-SIMS), Time-of-Flight Secondary Ion Mass Spectrometry(ToF-SIMS), and X-ray Photoelectron Spectroscopy(XPS). As the nitridation temperature increased, nitrogen concentration increased linearly, and more time was required to form the same reoxidized layer thickness. ToF-SIMS results showed that SiON species were detected at the initial oxide interface which had formed after NO annealing and $Si_2NO$ species within the reoxidized layer formed after reoxidation. As the anneal temperatures increased, the device showed worse retention and degradation properties. It could be said that nitrogen concentration near initial interface is limited to a certain quantity, so the excess nitrogen is redistributed within reoxidized layer and contribute to electron trap generation.

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.131-135
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• 2005

Gallium nitride (GaN) powders and nanowires were prepared by using tris(N,N-dimethyldithiocarbamato)gallium(III) (Ga(DmDTC)$_3$) and tris(N,N-diethyldithiocarbamato)gallium(III) (Ga(DeDTC)$_3$) as new precursors. The GaN powders were obtained by reaction of the complexes with ammonia in the temperature ranging from 500 to 1100 ${^{\circ}C}$. The process of conversion of the complexes to GaN was monitored by their weight loss, XRD, and $^{71}$Ga magic-angle spinning (MAS) NMR spectroscopy. Most likely the complexes decompose to $\gamma$ -Ga$_2$S$_3$ and then turn into GaN via amorphous gallium thionitrides (GaS$_x$N$_y$). The reactivity of Ga(DmDTC)$_3$ with ammonia was a little higher than that of Ga(DeDTC)$_3$. Room-temperature photoluminescence spectra of asprepared GaN powders exhibited the band-edge emission of GaN at 363 nm. GaN nanowires were obtained by nitridation of as-ground $\gamma$ -Ga$_2$S$_3$ powders to GaN powders, followed by sublimation without using templates or catalysts.

• 한국통신학회논문지
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• 제16권11호
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• pp.1179-1185
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• 1991

초박막 재산화 질화산화막을 $1050^{\circ}C-1100^{\circ}C$ 온도에서 20, 40초 동안 산소 분위기에서 램프 가열 방법의 급속 열처리 공정에 의해 형성 시켰다. 초박막의 전기적 특성은 누설전류, 항복전압, 시간종속 항복과 F-N 관통을 분석 하였다. 질화와 재산화 조건에 따른 전하포획의 의존성 즉 고전계 스트레스에 유기되는 항복전하량$(Q_{BD})$ 증가 여부와 평탄대역 전압이동$(\DeltaV_{FB})$을 연구하였다. 분석 결과에 의하면, 급속 열처리 재산화시 유전적 성질이 상당히 개선되었고, 항복전하량은 증가되었으며, 평탄대역전압은 감소 되었다.

• 한국결정성장학회지
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• 제9권3호
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• pp.320-326
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• 1999

금속 Al과 산화물{{{{{Al}_{2}{O}_{3}}}}}를 사용하여 Al의 직접질화법에 의한 ALON 합성실험을 행하여 Al의 첨가량의 변화에 따른 질화반응 거동과 ALON 반응소결체의 특성을 조사하였다. Al과{{{{{Al}_{2}{O}_{3}}}}}의 직접질화법에 의한 ALON 합성이 가능함을 확인하였다. 소결온도가 증가함에 따라 ALON의 생성량이 증가하였으며, Al 첨가량 10wt%까지는 $1750^{\circ}C$ 이상의 소결온도에서 ALON상만이 존재하였다. Al 첨가량 13wt% 이상의 조성에서는 약간의 AlN상이 ALON상과 공존하였다. 반응소결체의 밀도는 소결온도가 증가함에 따라 증가하였으나, AlN이 잔존하는 시편의 소결밀도는 $1750^{\circ}C$를 넘으면 약간 감소하였다. Al 첨가량이 증가할수록 입내파괴현상이 현저히 증가하였다.

• 한국세라믹학회지
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• 제46권5호
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• pp.452-455
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• 2009

A cost-effective route to synthesize $\beta$-SiAlONs from Si mixtures by reaction bonding followed by post-sintering was investigated. Three different z values, 0.45, 0.92 and 1.87, in $Si_{6-z}Al_zO_zN_{8-z}$ without excess liquid phase were selected to elucidate the mechanism of SiAlON formation and densification. For RBSN (reaction-bonded silicon nitride) specimens prior to post-sintering, nitridation rates of more than 90% were achieved by multistep heating to $1400^{\circ}C$ in flowing 5%$H_2$/95%$N_2$; residual Si was not detected by XRD analysis. An increase in density was acquired with increasing z values in post-sintered specimens, and this tendency was explained by the presence of higher amounts of transient liquid phase at larger z values. Measured z values from the synthesized $\beta$-SiAlONs were similar to the values calculated for the starting compositions. Slight deviations in z values between measurements and calculations were rationalized by a reasonable application of the characteristics of the nitriding and post-sintering processes.