• Journal of information and communication convergence engineering
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• 제1권2호
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• pp.67-69
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• 2003

The experimental studies for the etch properties of the oxide grown on silicon substrate, which is in diluted hydrogen fluoride (HF) solution, are presented. Using different ion implantation dosages, dopants and energies, silicon substrate was implanted. The wet etching in diluted HF solution is used as a mean of wafer cleaning at various steps of VLSI processing. It is shown that the wet etch rate of oxide grown on various implanted silicon substrates is a strong function of ion implantation dopants, dosages and energies. This phenomenon has never been reported before. This paper shows that the difference of wet etch rate of oxide by ion implantation conditions is attributed to the kinds and volumes of dopants which was diffused out into $SiO_2$ from implanted silicon during thermal oxidation.

• Korean Chemical Engineering Research
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• 제53권2호
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• pp.216-223
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• 2015

The present work explores the potential of wet air oxidation (WAO) for pretreatment of mixed lignocellulosic biomass to enhance enzymatic convertibility. Rice husk and wheat straw mixture (1:1 mass ratio) was used as a model mixed lignocellulosic biomass. Post-WAO treatment, cellulose recovery in the solid fraction was in the range of 86% to 99%, accompanied by a significant increase in enzymatic hydrolysis of cellulose present in the solid fraction. The highest enzymatic conversion efficiency, 63% (by weight), was achieved for the mixed biomass pretreated at $195^{\circ}C$, 5 bar, 10 minutes compared to only 19% in the untreated biomass. The pretreatment under the aforesaid condition also facilitated 52% lignin removal and 67% hemicellulose solubilization. A statistical design of experiments on WAO process conditions was conducted to understand the effect of process parameters on pretreatment, and the predicted responses were found to be in close agreement with the experimental data. Enzymatic hydrolysis experiments with WAO liquid fraction as diluent showed favorable results with sugar enhancement up to $10.4gL^{-1}$.

• 한국재료학회지
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• 제27권4호
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• pp.221-228
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• 2017

Various morphologies of copper oxide (CuO) have been considered to be of both fundamental and practical importance in the field of electronic materials. In this study, using Cu ($0.1{\mu}m$ and $7{\mu}m$) particles, flake-type CuO particles were grown via a wet oxidation method for 5min and 60min at $75^{\circ}C$. Using the prepared CuO, AlN, and silicone base as reagents, thermal interface material (TIM) compounds were synthesized using a high speed paste mixer. The properties of the thermal compounds prepared using the CuO particles were observed by thermal conductivity and breakdown voltage measurement. Most importantly, the volume of thermal compounds created using CuO particles grown from $0.1{\mu}m$ Cu particles increased by 192.5 % and 125 % depending on the growth time. The composition of CuO was confirmed by X-ray diffraction (XRD) analysis; cross sections of the grown CuO particles were observed using focused ion beam (FIB), field emission scanning electron microscopy (FE-SEM), and energy dispersive analysis by X-ray (EDAX). In addition, the thermal compound dispersion of the Cu and Al elements were observed by X-ray elemental mapping.

• 한국전기전자재료학회논문지
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• 제21권11호
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• pp.981-986
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• 2008

The conventional IGBT has two problems to make the device taking high performance. The one is high on state voltage drop associated with JFET region, the other is low breakdown voltage associated with concentrating the electric field on the junction of between p base and n drift. This paper is about the structure to effectively improve both the lower on state voltage drop and the higher breakdown voltage than the conventional IGBT. For the fabrication of the circular trench IGBT with the circular trench layer, it is necessary to perform the only one wet oxidation step for the circular trench layer. Analysis on both the on state voltage drop and the breakdown voltage show the improved values compared to the conventional IGBT structure. Because the circular trench layer disperses electric field from the junction of between p base and n drift to circular trench, the breakdown voltage increase. The on state voltage drop decrease due to reduction of JFET region and direction changed of current path which pass through reversed layer channel. The electrical characteristics were studied by MEDICI simulation results.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2002년도 춘계학술발표논문집 (상)
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• pp.631-634
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• 2002

In this paper we improved that hump occurrence by increased oxidation thickness, and control field oxide recess$(\leq20nm)$, wet oxidation etch time(19HF, 30sec), STI nitride wet cleaning time(99 HF, 60sec + P 90min) and gate pre-oxidation cleaning time(U10min+19HF, 60sec) to prevent hump occurring at STI channel edge.

• 한국시뮬레이션학회논문지
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• 제11권1호
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• pp.23-30
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• 2002

An STI(Shallow Trench Isolation) by using a CMP(Chemical Mechanical Polishing) process has been one of the key issues in the device isolation[1] In this paper we fabricated N, P-MOSFEET tall analyse hump characteristics in various rounding oxdation thickness(ex : Skip, 500, 800, 1000$\AA$). As a result we found that hump occurred at STI channel edge region by field oxide recess. and boron segregation(early turn on due to boron segregatiorn at channel edge). Therefore we improved that hump occurrence by increased oxidation thickness, and control field oxide recess( 20nm), wet oxidation etch time(19HF,30sec), STI nitride wet cleaning time(99HF, 60sec+P 90min) and fate pre-oxidation cleaning time (U10min+19HF, 60sec) to prevent hump occurring at STI channel edge.

• 자원리싸이클링
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• 제11권4호
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• pp.3-10
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• 2002

핵연료 원료인 $UO_2$ 분말을 사용해 원자로에서 연소된 사용후 핵연료 소결체를 모의 제조하여 1회 산화ㆍ환원처리하여 분말로 만든 후, 건ㆍ습식 attrition 분쇄에 따른 분말의 특성 및 소결성을 조사하였다. 분쇄에 의한 분말의 평균입자크기는 건식분쇄의 경우에는 1 $mu extrm{m}$ 이하인 미분말이 쉽게 생성되었으나, 습식분쇄에서는 그 이상의 분말만이 생성되었다. 그리고 분쇄분말의 비표면적은 건식분쇄한 경우가 습식분쇄한 경우 보다 높았다. 분말의 미세구조는 건식분쇄에 의해서는 느슨한 응집체가 형성되었으며, 습식분쇄 분말은 압분성이 낮은 불규칙적이고 각진 입자형태를 나타내었다. 건식분쇄에 의해서 압분체 밀도는 크게 증가하며 소결체 요구 조건을 만족하는 이론밀도의 95%이상이 되고 평균 결정립 크기가 8 $\mu\textrm{m}$이상인 소결체를 얻을 수 있었다.

• 한국축산식품학회지
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• 제44권4호
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• pp.899-911
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• 2024

This research investigated the synergic outcome of high intensity ultrasound (HIU) treatment and wet-dry combined aging (WDCA) on physiochemical characteristics and lipid oxidation during refrigerated storage to ameliorate pork meat's quality and shelf life. The CIE b^* values, cooking loss (CL %), and pH of the HIU treated samples were higher than those of the control over the aging period. They were significantly (p<0.05) modified by the aging period and ultrasound (US) treatment. However, the released water (RW %) and moisture were not significantly influenced by US treatment (p>0.05). The Warner-Bratzler shear force of HIU-treated samples was lower over control values except in 7-14 d, and it showed a significant difference between control and US treatment according to the significance of HIU (p<0.05). The thiobarbituric acid reactive substance of HIU-treated samples was significantly higher (p<0.05) than control values over the aging period. These results suggested that HIU treatment and WDCA showed a synergistic effect of maximizing the tenderness, but lipid oxidation was higher than before ultrasonic treatment. In agreement with this, the most favorable approach would involve implementing wet aging for a period of two weeks followed by dry aging for a period not exceeding one week after the application of HIU.

• 한국광학회:학술대회논문집
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• 한국광학회 1999년도 제16회 광학 및 양자전자 학술발표회Proceedings of 16th Optics and Quantum Electronics Conference, 1999
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• pp.228-229
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• 1999

• 한국재료학회:학술대회논문집
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• 한국재료학회 1993년도 춘계학술발표회
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• pp.34-34
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• 1993