• Korean Journal of Materials Research
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• v.3 no.4
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• pp.403-409
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• 1993

In this paper, an $NH_3$, added during dry oxidation and annealing m Si( 111) is clarified effect ive to suppress or remove defects. Annealing effects in $N_2$ and $NH_3/N_2$ ambient are estimated with dry $O_2$ and $NH_4$ oxidation($NH_3$ added in dry $O_2$ oxidation) method. C;em'rated defects in dry $O_2$ oxidation are lengthened according to oxidation time. but any defects in $NH_3$ oxidation are not found. Dry oxidation, after $NH_3$ oxidation as an initial oxidation. lias the defect -removing effect at the interface of Si -$SiO_2$. After dry or $NH_3$. oxidation. the annealmg 7.5% $NH_3/N_2$ ambient brings out gettering effect of OSF. The annealing in 7.5% $NH_3/N_2$ ambient for NI L oxidation method decreaSE,s $NH_3$ length of OSF about 20 % compared with dry oxidation method. Tlw feature of OSF is pit type, the gettering is directed to (011) plane for (111) plane. and OSFs are etched following to 110) directIon.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.57-58
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• 1992

The NH$_3$oxidation, which forms thermal oxide layer on silicon substrate with pure $O_2$gas added with small amounts of NH$_3$gas, has good interface sates due to activated gettering effect during oxidation. The superiority of interfae state in NH$_3$ oxidation method is not affected by preprocess but by gettering during oxidation. The dramatec reduction fo interface state is conformed with observing OSF when NH$_3$ oxide is annealed in NH$_3$ atmosphere.

• Journal of the Korean Vacuum Society
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• v.7 no.2
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• pp.82-87
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• 1998

In the oxidation process of the $NH_3/O_2$ oxidation method, adding $NH_3$ gas to $O_2$ gas, the detected outlet gases in the reaction quartz chamber are N2, $O_2$ and $H_2O$ and in addition, a very small quantity of $CO_2$, NO and $NO_2$ are detected. Two kinds of species ($O_2$ and H2O) contribute to oxidation, so the growth rate is determined by oxidation temperature and by also partial pressure of the NH3 and $O_2$ gases. The slop of growth rate is identified to be medial and in parallel between that of the dry and wet oxidation. Auger electron spectroscopy (AES) indicates that $NH_3/O_2$ oxide film has a certain stoichiomerty of $SiO_2$, this oxidation method restrains the generation of defects in the $SiO_2/Si$ interface, minimizing fixed charges. The breakdown voltage of $NH_3/O_2$ oxide film (470$\AA$) is 57.5 volts, and the profile of the C-V curve including flat band voltage (0.29 volts) agree with the ideal curve.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.363-366
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• 1988

A new $NH_{3}-O_{2}$ oxidation method was estimated by the electrical properties of the fabricated n-MOS transistor. For the C-V characteristic curves the Qox are almost equal to Qss and no hysteresis phenomena are observed. The Id-Vds characteristics show that $NH_{3}-O_{2}$ oxidation method is superior to Dry oxidation.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.645-649
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• 2013

In this study, we investigated the $NH_3$ oxidation reaction characteristic over $W/TiO_2$ catalyst in order to control $NH_3$ generated from a thermoelectric power plant or incinerator. As a result, it was found that the optimal content of tungsten in $W/TiO_2$ catalyst is 10 wt% and $NH_3$ removal efficiency decreased due to decreasing specific surface areas of catalyst with increasing tungsten contents. When $NH_3$ was injected more than 420 ppm, $NH_3$ conversion decreased at the middle temperature range. In addition, $NH_3$ conversion decreased due to the competitive adsorption of moisture and with increasing oxygen concentration, the $NH_3$ conversion increased while the $N_2$ selectivity decreased.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.1
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• pp.25-33
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• 2006

The objective of this research is to improve the adsorption capacity of adsorbent made from MSWI (Municipal Solid Waste Incinerator) fly ash by surface oxidation. Used oxidation agents were $HNO_{3}$, $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$. These agents can modify the surface property of an adsorbent such as specific surface area, pore volume, and functional group. The surface structure was studied by BET method with $N_{2}$ adsorption. The acid value and base value were determined by Boehm's method. The adsorption properties were investigated with benzene and MEK (Methylethylketone). According to the results, the specific surface area of the adsorbent was increased from 309.2 $m^{2}$/g to 553.2 $m^{2}$/g by $HNO_{3}$ oxidation. But $H_{2}SO_{4}$ and $(NH_{4})_{2}S_{2}O_{8}$ oxidation was decreased slightly. After Oxidation, surface acid value increased, but base value decreased. FAA-N shows the highest acid value. The content of oxygen increased greatly and oxygen group was created on the adsorbent surface. The surface oxidation improved the adsorbing capacity for MEK. The amount of adsorbing MEK was increased from 189 $m^{2}$/g to 639 $m^{2}$/g by $HNO_{3}$ oxidation.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.11
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• pp.1329-1334
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• 1988

A new method was developed for growing oxidation film by thermal reaction of $NH_3$ and $O_2$. The growth rate increased with the increase of partial pressure of $NH_3$. Optical transparency of the growth film was 12% at the wave number 1100 $cm^{-1}$ compared with 17% by thermal dry oxidation method, and the quality was much better. In C-V characteristic curve, $Q_{OX}$ was almost equal to $Q_{SS}$ and no hysteresis phenomena was observed. n-MOS transistors fabricated with this new method showed $I_D$-$V_{DS}$ characteristics better than thermal dry oxidation method.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.360-362
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• 1988

The new oxidation method was presented to grow the oxide layer by thermal reaction of $NH_{3}$ and $O_{2}$. The growth rate increased according as increase of partial pressure of $NH_{3}$. Optical transparent of the grown film was 12% compared with 17% of thermal oxidation when the wave number was $1,100cm^{-1}$. The oxide layer with good quaility was obtained.

• Journal of the Korean Society of Combustion
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• v.12 no.4
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• pp.39-46
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• 2007

The technique of $NH_3$ SCR (selective catalytic reduction) assisted by plasma oxidation has been applied to a 2,000 cc diesel engine. The present combined $deNO_x$ process consists of two steps. The first step is that about 50% of emitted NO from the engine is oxidized to $NO_2$ in a plasma oxidation process. The second step is that NO and $NO_2$ are simultaneously reduced to $N_2$ in the $NH_3$ SCR process. The engine test results showed that the $deNO_x$ rates of the present combined process are higher than those of conventional SCR process by 20%. Such a high performance of the combined process is noticeable especially, when the exhaust temperature are relatively low, i.e., $170-220^{\circ}C$. To provide a feasibility of the present technique the effects of operating conditions, such as an electrical input energy, an exhaust gas temperature, an initial NO concentration, and the amount of hydrocarbon addition, were discussed.

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.05a
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• pp.165-166
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• 1994

The depth profiles of the as-grown and the annealed NH$_3$ oxide film in NH$_3$(7.5%)/$N_2$ ambient at 45$0^{\circ}C$ are analized . This annealing in the ambient of mixed gases removes the small quantities of N component from the NH$_3$ oxide film. In AES analysis, the NH$_3$ oxidation shows the exact stoichiometry of SiO$_2$ and a sharp slop at SiO$_2$/Si interface.