• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.908-909
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• 2006

The HTCC based multilayer structure plasma head unit have some difficulties in fabrication due to complicated post-processes, such as heat treatment at reduced atmosphere, re-bonding of each layer, and silver metallization. On the other hand, LTCC based technology provides relatively simple process for multilayer plasma unit except weak mechanical properties. To overcome this problem a combined scheme using both LTCC and HTCC technology has been developed in our group, recently. In this work, we report the structural design, materials selection, joining of LTCC with HTCC substrate, and co-firing process for the fabrication of multilayered atmospheric plasma head unit.

• Journal of Biosystems Engineering
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• 제43권3호
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• pp.229-236
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• 2018

Purpose: Makgeolli is a traditional alcoholic beverage made from rice with a fermentation starter called "nuruk." The concentration of alcohol in makgeolli depends on the temperature of the fermentation tank. It is important to monitor the alcohol concentration to manage the makgeolli production process. Methods: Data were collected from 84 makgeolli fermentation tanks over a year period. Independent variables included the temperatures of the tanks and the room where the tanks were located, as well as the quantity, acidity, and water concentration of the source. Software for the multilayer perceptron model (MLP) was written in Python using the Scikit-learn library. Results: Many models were created for which the optimization converged within 100 iterations, and their coefficients of determination $R^2$ were considerably high. The coefficient of determination $R^2$ of the best model with the training set and the test set were 0.94 and 0.93, respectively. The fact that the difference between them was very small indicated that the model was not overfitted. The maximum and minimum error was approximately 2% and the total MSE was 0.078%. Conclusions: The MLP model could help predict the alcohol concentration and to control the production process of makgeolli. In future research, the optimization of the production process will be studied based on the model.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.291-297
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• 2010

This article introduces a facile nanoparticle self-assembly/annealing method for the preparation of nanoisland films. First, nanoparticle-polymer multilayer films are prepared with layer-by-layer assembly. Nanoparticle multilayer films are then annealed at $~500^{\circ}C$ in air to evaporate organic matters from the films. During the annealing process, the nanoparticles on the solid surface undergo nucleation and coalescence, resulting in the formation of nanostructured gold island arrays. By controlling the overall thickness (number of layers) of nanoparticle multilayer films, nanoisland films with various island density and different average sizes are obtained. The surface property of gold nanoisland films is further controlled by the self-assembly of alkanethiols, which results in an increased surface hydrophobicity of the films. The structure and characteristics of these nanoisland film arrays are found to be quite comparable to those of nanoisland films prepared by vacuum evaporation method. However, this self-assembly/annealing protocol is simple and requires only common laboratory supplies and equipment for the entire preparation process.

• 마이크로전자및패키징학회지
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• 제6권4호
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• pp.15-22
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• 1999

일반적으로 빌드업 다층 인쇄회로기판은 에칭, 도금등의 습식공정에 의해 제작이 이루어지므로 많은 장비와 많은 시간이 필요하게 된다. 이러한 습식공정은 양산에는 적합하지만 개발단계에서는 그리 적합하지 않은 방법이다. 본 연구에서는 스크린 인쇄기술을 도입하여 빌드업 다층 인쇄회로기판을 제작하여 보았다. 절연성 재료로는 광경화성수지 또는 열경화성수지를 사용하였으며 전도성 재료로는 전도성 페이스트를 사용하였다. 층간의 전기적 연결을 담당하는 비아와 회로를 형성하기 위해 스크린 인쇄공정을 통해 전도성 페이스트를 인쇄 하였다. 이러한 방법을 통해 제품의 개발 단계에서 기존의 빌드업 다층 인쇄회로기판 제작 공정과 비교하여 좀더 효율적인 방법을 제시하였다.

• 한국광학회지
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• 제9권5호
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• pp.300-306
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• 1998

광학용 유전체 다층박막의 증착시 높은 열로 인해 형성되는 층간확산의 광학적 효과를 연구하였다. 연속적으로 변하는 굴절률 분포함수를 갖고 하나의 부분구조가 주기적으로 반복되는, 다층박막의 광특성 계산방법을 제시한다. 이 방법을 이용하여 Fabry-Perot형 여과막, 넓은 영역에 걸쳐 높은 반사율을 갖는 전반사경 및 반사 방지막에 대해 층간확산이 미치는 영향을 계산하여 투과 및 반사 스펙트럼을 얻었다. 층간확산으로 인하여 전반사경의스펙트럼 대역폭이 줄어들었으며 다층 반사방지막의 경우층의 수가 많을 때 특성이 악화되고 파장에 따른 반사율의 변화가 크게 되었다.

• 폴리머
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• 제29권4호
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• pp.392-398
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• 2005

Layer-by-layer(LbL) 흡착에 의한 poly(ethylene-alt-m미? anhydride) (PEMAh)/poly(4-vinyl pyridine) (P4VP) 자기조립 다층박막을 제조하였다. 자기조립 다층막을 이루는 PEMAh/P4VP 두 고분자 사이의 수소 결합과 정전기적 인력이 다층막을 이루는 원동력이라는 것이 푸리에 변환 적외선(FT-IR) 분광분석에 의해서 확인되었다. 다층막의 균일한 자기조립 과정은 PEMAh/P4VP 이중층막의 적층 수 증가에 따른 UV-vis 스펙트럼의 256 nm에서 나타나는 P4VP 특성 흡수 피크의 선형적 증가에 의해서 확인할 수 있었다. 다층막을 이루는 고분자 전해질 담지 용액의 조건 변화가 다층막 형성에 미치는 영향을 살펴보기 위하여 두 고분자 용액의 농도 및 PEMAh 담지용액의 pH를 변화시키면서 다층막을 제조하였다. 다층막의 두께, 흡착된 고분자 전해질 질량 및 표면 거칠기의 변화를 UV-vis 분광 분석, 수정진동자 미량저울(quartz crystal microbalance;QCM) 및 원자 힘 현미경(atomic force microscopy;AFM)을 이용하여 측정하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.125-126
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• 2005

Recently semiconductor devices are required more smaller scale and more powerful performance. For smaller scale of device, multilayer structure is proposed. And, for the higher performance, interconnection material is change to copper, because copper has high EM(Electro-migration)and low resistivity. Then copper CMP process is a great role in a multilayer formation of semiconductor. Copper process is different from aluminum process. ECP process is one of the copper processes. In this paper, we focused on the defects tendency by copper thickness which filled using ECP process. we observed hump high and dishing. Conclusively, hump hight reduced at copper thickness increased Also dishing reduced.

• 전기학회논문지
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• 제63권11호
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• pp.1533-1537
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• 2014

$WO_3/Ag/WO_3$ multilayer was researched by using RF magnetron sputtering with transparent electrode. Process gas flow ratio with $Ar/O_2$ were selected the optimum conditions at 70sccm/2sccm and $WO_3$ thin film at its conditions was appeared at transmittance about 80% in the visible light region to the average. $WO_3/Ag/WO_3$ multilayer thin films were fabricated from the same process condition which was the same gas flow ratio of Ar and $O_2$ $WO_3/Ag/WO_3$ thin films were appeared transmittance about 93% and sheet resistance about $6.41{\Omega}/{\square}$. From the SEM images, each thin films were appeared when $WO_3$ is 40nm and $O_2$ is 10nm.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1575-1577
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• 2009

We have investigated the characteristics of transparent indium zinc oxide(IZO)/Ag/IZO multilayer electrode grown on polyethylene terephthalate (PET) substrates using a specially designed roll-to-roll sputtering system for use in flexible device are described. By the continuous R2R sputtering of the bottom IZO, Ag, and top IZO layers at room temperature, we were able to fabricate an IZO-Ag-IZO multilayer electrode with a sheet resistance of 6.15 ${\Omega}$/square, optical transmittance of 87.4 %, and figure of merit value of 42.03 10-3 ${\Omega}$-1. In addition, the IZO-Ag-IZO multilayer electrode exhibited superior flexibility to the RTR sputter grown single ITO electrode, due to the existence a ductile Ag layer between the IZO layers. This indicates that the RTR sputtered IZO-Ag-IZO multilayer is a promising flexible electrode that can substitute for the conventional single ITO electrode grown by bath type sputtering for use in low cost flexible device, due to its low resistance, high transparency, superior flexibility and fast preparation by the R2R process.

• 한국전기전자재료학회논문지
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• 제20권12호
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• pp.1044-1048
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• 2007

With development of electronic products the demands for miniaturization and weight-lightening have increased until a recent date. Accordingly, The effort to substitute glass substrates was widely made. However, polymer substrates have weak point that substrates were damaged at high temperature. In this paper, we deposited transparent conductive film at low temperature. And we inserted Au thin film between oxide to compensate for deteriorated electrical characteristics. Ga-doped ZnO(GZO) multilayer coatings were deposited on glass substrate by DC sputtering. The optimization of deposition conditions of both AZO and Au layers were performed to obtain better electrical and optical characteristics in advance. We presumed that the properties of multilayer were affected by the deposition process of both GZO and Au layers. The best multilayer coating exhibited the resistivity of $2.72{\times}10^{-3}\;{\Omega}-cm$ and transmittance of 77 %. From these results, we can confirm a possibility of the application as transparent conductive electrodes.