• 한국작물학회지
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• 제41권6호
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• pp.672-677
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• 1996

전자코를 이용하여 향미품종에 대한 방향성 성분함량비율을 조사한 결과를 요약하면 다음과 같다. 1. 작용기별로는 polar compound계열과 aldehydes compounds계열이 apolar compounds 계열과 sulphur compounds, aminated com-pounds계열에 비해 약 3배정도 높은 함량 비율을 보였다. 2. 백미와 취반상태에 있어서 방향성 성분 함량변화는 대부분 0.02에서 0.1수준으로 증가하는 경향을 보였으나, 찰성을 가진 밀양 14006의 경우는 취반 상태에서 방향성 성분의 함량이 오히려 감소하는 경향을 보였다. 3. 향기와 amylose함량 관계에서는 Japonica와 Indica계열 모두 아밀로스함량이 높을수록 방향성 성분의 함량이 증가하는 경향을 보였다. 4. Headspace 진행 후 센서에 감지되는 시간대는 대부분의 품종에서 30～35초에서 가장 많은 향기성분의 양을 검출할 수 있었으나, 이리 41003의 경우는 방향성성분의 검출이 30초대 이후에 급격히 감소하였다.

• 한국세라믹학회지
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• 제48권4호
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• pp.312-315
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• 2011

The effect of slurry composition and wafer flatness on a material removal rate (MRR) and resulting surface roughness which are evaluation parameters to determine the CMP characteristics of the on-axis 6H-SiC substrate were systematically investigated. 2-inch SiC wafers were fabricated from the ingot grown by a conventional physical vapor transport (PVT) method were used for this study. The SiC substrate after the CMP process using slurry added oxidizers into slurry consisted of KOH-based colloidal silica and nano-size diamond particle exhibited the significant MRR value and a fine surface without any surface damages. SiC wafers with high bow value after the CMP process exhibited large variation in surface roughness value compared to wafer with low bow value. The CMPprocessed SiC wafer having a low bow value of 1im was observed to result in the Root-mean-square height (RMS) value of 2.747 A and the mean height (Ra) value of 2.147 A.

• 센서학회지
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• 제29권4호
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• pp.232-236
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• 2020

Three-dimensional (3D) multilayered Pt electrodes were fabricated to develop a porous electrode using a pattern-transfer printing process. The Pt thin films were deposited using a transferred sputtering pattern having a 250 nm line width on the substrate, and the uniform line patterns were efficiently transferred using our proposed method. Temperature-programmed desorption (TPD) analyses were used to evaluate the porosity of the electrodes. It was possible to distinguish between two resolved maxima at 168 and 227 ℃, which could be described in terms of desorption reactions on the Pt (111) planes. The results of the TPD analysis of the 3D and multilayered Pt electrodes prepared through transfer printing were compared to those of an electrode fabricated through screen printing using a commercial Pt-carbon paste commonly used as porous electrodes. It was confirmed that the 3D multilayered electrodes exhibited a desorption concentration approximately 100 times higher than that of the Pt-carbon composite electrode, and the desorption concentration increased by approximately 0.02 mg/mol per layer. The 3D multilayered electrode effectively functions as a porous electrode and a catalyst.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2000년도 추계 기술심포지움 논문집
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• pp.57-57
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• 2000

본 논문에서는 MCM 및 패키지의 Lid로 사용되는 합금인 Kovar (Fe-Ni-Co alloy) 와 LTCC (Low Temperature Co-fired Ceramics) 간의 Brazing 특성을 연구하였다. 기존에 사용되고 있는 알루미나 패키지의 경우, 주로 80$0^{\circ}C$ 이상의 온도에서 Brazing을 실시하고 있으며, 조성은 Ag-Cu 계열을 사용하고 있다. 하지만, LTCC 의 경우, 소결온도가 85$0^{\circ}C$ 내외로서 기존의 방법을 그대로 적용하기는 어려움이 있다. 또한 Brazing 특성에 따른 접착 강도는 Brazing Alloy 의 영향뿐만 아니라 LTCC 와 전도체 전극사이의 Metallization 에 크게 영향을 받는다. 따라서, 본 논문에서는 Brazing Alloy의 종류 (Ag-Cu, Au-Sn) 및 Brazing 조건에 따른 Brazing 특성뿐만 아니라, 전도체 전극내 유리질 함량에 따른 Brazing 특성을 평가하여 LTCC/Kovar 간의 최적의 Brazing 조건을 구현하고자 하였다.

• 대한금속재료학회지
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• 제46권7호
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• pp.458-463
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• 2008

High purity Fe thin films were prepared by the ion beam deposition method with $^{56}Fe^{+}$ions on the Si substrate at the room temperature. The Fe thin films were deposited at the ion energy of 50 eV and 100 eV. Microstructural properties were investigated on the atomic scale using high-resolution transmission electron microscopy (HRTEM). It was found that the Fe thin film obtained with the energy of 50 eV having an excellent corrosion resistance consists of the amorphous layer of ~15 nm in thickness and the bcc crystalline layer of about 30 nm in grain size, while the thin film obtained with the energy of 100 eV having a poor corrosion resistance consists of little amorphous layer and the defective crystalline layer. Furthermore the crystal structures and arrangements of the oxide layers formed on the Fe thin films were analyzed by processing of the HRTEM images. It was concluded that the corrosion behavior of Fe thin films relates to the surface morphology and the crystalline structure as well as the degree of purification.

• 기술사
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• 제24권5호
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• pp.9-14
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• 1991

To date Korean electronic industry has held a position of the first rank both in productions and exports among the nation's industries. However, it is gradually losing its competitive foundation in the world market owing both to the weakening in price competition by least developed among developing countries(LDDC) and to the lack in technological competition with industrially advanced countries. Specifically it is worried about an industrial subordination to industrially advanced countries owing to an evasion of components supply, control of amount of materials, and the evasion of kernel technology transfer etc. As the condition has developed, both the government and the electronic industry in July of this year came to jointly establish a research and development center for electronic components for the purpose of rehabilitating the electronic industry and accordingly strengthen the export industry which has been and continuance to be vital to our nation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.321-322
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• 2005

In this paper, we dealt with a partial discharge(PD) measurement system that has been accepted as an effective and non-destructive technique for estimating reliabilities of low-voltage electrical and electronic components. Calibration tests on laboratory set-up have shown that the PD measurement system has a stable sensitivity of 37.6 mv/pC. In an application test on photo coupler, we could detect 0.1 pC level of partial discharge at the applied voltage of AC 520 $V_{peak}$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.202-202
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• 2008

The world gross market of many kinds of electronics, such as TV and mobile phone has been increasing rapidly these days. It is mainly caused by the amazing developments of IT technology during past decade and the changes of individual life style for the better. Thanks to the increases of electronics manufactured in quantity, much more electronic components such as MLCC (multi layer ceramic capacitor) and PCB (printed circuit board), which are our main products, have been needed as a consequence. Though it was reported that total market of electronic components exceeds several hundreds of billion dollars, there are many manufactures struggling for survival in the competition of electronics components. Then the recognition of quality as a key technology has spread and the efforts for high-yield production lines have been kept in many companies. In this paper, our efforts to eliminate the contamination of particles and the diffusion of some volatile organic compounds which is very harmful to workers at production line have been introduced.

• 동력기계공학회지
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• 제20권6호
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• pp.20-26
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• 2016

For power electronic devices, the thermal energy density per unit volume has seen a rapid increase in recent years, owing to the miniaturization and dense integration of electronic components, as well as the continuous development in performance and function. This research examined the validity and reliability of a thermal safety model for managing the heating conditions of TRIAC electronic components. Among the electronic components of a PCB, these can be considered as a heat source. Using the model, the heating conditions of TRIAC components were maintained at their design target levels in the process of developing an LMT motor drive board. In addition, the heating characteristics of the entire PCB were analyzed to verify its thermal safety. Finally, the reliability and validity of the thermal safety model for maintaining the heating conditions of the TRIAC electronic elements at adequate levels was verified using a numerical analysis method.

• 마이크로전자및패키징학회지
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• 제24권1호
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• pp.57-65
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• 2017

모바일 기기 내부에 있는 전자부품들은 반도체 칩이나 그 밖의 여러 가지 재료로 구성되어 있다. 이러한 전자부품들은 매우 얇고, 구성된 재료들은 다양한 열팽창 계수를 가지고 있으므로 온도 변화나 외부 하중에 의해서 쉽게 굽힘이 일어난다. 그림자 무아레 방법은 비접촉으로 전체 영역에 걸친 면외변위를 측정하는 광학적 방법이지만 측정 감도를 $50{\mu}m/fringe$ 이내로 하기 어려워서 반도체 패키지의 굽힘변형을 측정하기에는 적당하지 않은 면이 있었다. 본 논문에서는 그림자 무아레 기법의 여러 실험조건들을 최적화하여 $25{\mu}m/fringe$의 향상된 감도를 갖는 측정 방법을 구현하였다. 또한 이로부터 위상이동에 의해 기록되는 4장의 그림자 무늬를 영상 처리하여 감도가 4배 향상된 그림자 무늬를 얻어내고 이를 스마트폰의 소형 전자부품들에 적용하여 온도변화에 따라 발생하는 굽힘 변위를 $5{\mu}m/fringe$의 고감도로 측정하였다.