• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.278-278
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• 2009

A photovoltaic device consisting of arrays of radial p-n junction wires enables a decoupling of the requirements for light absorption and carrier extraction into orthogonal spatial directions. Each individual p-n junction wire in the cell is long in the direction of incident light, allowing for effective light absorption, but thin in orthogonal direction, allowing for effective carrier collection. To fabricate radial p-n junction solar cells, p or n-type vertical Si wire cores need to be produced. The majority of Si wires are produced by the vapor-liquid-solid (VLS) method. But contamination of the Si wires by metallic impurities such as Au, which is used for metal catalyst in the VLS technique, results in reduction of conversion efficiency of solar cells. To overcome impurity issue, top-down methods like noble metal catalytic etching is an excellent candidate. We used noble metal catalytic etching methods to make Si wire arrays. The used noble metal is two; Au and Pt. The method is noble metal deposition on photolithographycally defined Si surface by sputtering and then etching in various BOE and $H_2O_2$ solutions. The Si substrates were p-type ($10{\sim}20ohm{\cdot}cm$). The areas that noble metal was not deposited due to photo resist covering were not etched in noble metal catalytic etching. The Si wires of several tens of ${\mu}m$ in height were formed in uncovered areas by photo resist. The side surface of Si wires was very rough. When the distance of Si wires is longer than diameter of that Si nanowires are formed between Si wires. Theses Si nanowires can be removed by immersing the specimen in KOH solution. The optimum noble metal thickness exists for Si wires fabrication. The thicker or the thinner noble metal than the optimum thickness could not show well defined Si wire arrays. The solution composition observed in the highest etching rate was BOE(16.3ml)/$H_2O_2$(0.44M) in Au assisted chemical etching method. The morphology difference was compared between Au and Pt metal assisted chemical etching. The efficiencies of radial p-n junction solar Cells made of the Si wire arrays were also measured.

• 한국산학기술학회논문지
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• 제13권9호
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• pp.4126-4130
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• 2012

본 논문에서는 고주파수 무선 신호 전송을 위한 AC 커플링(Coupling) 기반의 평면 나선형 인덕터를 제안하고, 이에 대한 다양한 구조의 인덕터를 설계, 모델링 및 특성을 분석하였다. 커패시턴스의 의한 영향을 줄이기 위해서는 두 박막 인덕터가 서로 평행하게 위치함으로서 인덕터 간의 커패시턴스를 줄여야 한다. 이를 위해 두 가지 구조를 제안하였다. 첫 번째 구조는 inter-diagonal 구조로 평행한 두 인덕터의 도선 부분이 겹치지 않게 만든 구조이다. 이 구조의 경우 비록 평행하게 겹치지는 않지만 도선의 두께와 폭이 좁으므로 서로 엇갈리는 위치에 도선이 위치하더라도 실제 커패시턴스의 변화가 작아서 전체적인 S-파라미터의 특성이 크게 변하지 않았다. 두 번째 구조는 On-chip형 구조로 두 박막 인덕터가 평행하게 존재하지만 마주보지 않게 사선형으로 배치한 구조이다. 이 구조의 경우 박막 인덕터 간의 수평거리가 길어짐에 따라 두 번에 걸쳐서 일어나는 공진이 한 번으로 줄어드는 것을 볼 수 있는데, 이는 두 인덕터 간의 거리가 멀어짐으로 인해 박막 인덕터 간의 커패시턴스 영향이 점점 줄어들기 때문이다.

• 한국진공학회지
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• 제16권6호
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• pp.439-445
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• 2007

RF 및 고속 아날로그 특성 및 제조 공정의 용이성에 의하여 고속 유무선통신 및 초고주파 분야에서 많이 이용되고 있는 SiGe 집적회로에서, SiGe 박막 저항기의편차를 줄여 집적회로의 신뢰성을 높이는 것이 중요하다. 본 논문에서는 실리콘계 박막 저항기 제조 후 발생하는 불균일한 저항 값 분포의 원인 규명과 그 해결 방안에 대하여 고찰한다. SiGe 박막 저항기의 실리사이드가 존재하는 컨택 영역에서 Ti-B석출물의 영향으로 인하여 저항 값의 불균일성 발생하는데, 이를 최소화하기 위하여는 가능한 최대의 boron 이온을 주입할 필요가 있다. SiGe 저항기와 금속을 배선하기 위한 컨택 홀의 크기가 작을수록 SiGe 층 내에서 돌출부가 컨택 홀의 전체면적을 차지하게 될 확률이 커지게 되어 접촉저항이 비정상적으로 커질 확률 또한 높아지게 되므로, 돌출부가 생성되는 SiGe 저항기의 경우는 컨택 홀의 면적을 크게하여 SiGe 저항기의 편차를 개선하였다.

• 센서학회지
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• 제1권1호
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• pp.53-57
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• 1992

본 연구는 $CdS_{1-x}Se_{x}$의 박막을 제작하고 그 전기-광학적인 특성을 조사한 것이다. 전자선 가열증착법을 이용하여 $CdS_{1-x}Se_{x}$을 알루미나 기판위에 $1.5{\times}10^{-7}$ torr의 압력, 4kV의 전압, 2.5 mA의 전류 그리고 기판온도를 $300^{\circ}C$로 유지하여 증착하였다. 증착된 $CdS_{1-x}Se_{x}$ 박막은 X-ray 회절 실험을 통하여 볼 때, 육방정계의 결정구조를 가지며 성장되었다. $CdS_{1-x}Se_{x}$ 도전막은 특정분위기에서 $550^{\circ}C$, 30분간 열처리함으로써 높은 광전도성을 나타내게 되었다. 또한 Hall 효과, 광전류 스펙트럼, 감도, 최대 허용 전력과 응답시간 등을 조사하였다.

• 한국정밀공학회지
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• 제17권12호
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• pp.145-150
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• 2000

Micro punching is one of general methods to fabricate simple holes such as permanent ink-jet printer nozzles. A thin punch, that is need for micro punching, usually has been obtained by mechanical machining. There are some method to obtain a thin punch from a cylindrical rod, e.g., microgrinding and WEDG (Wire Electro-Discharge Grinding). Inefficiently, only one punch can be obtained from these machining methods. In contrast with these methods, many punches can be fabricated simultaneously by electrochemical process. Electrochemical process has usually aimed to obtain very sharp probe for atomic force microscopy (AFM) or scanning tunneling microscopy (STM), and it has not been considered the whole shape of a probe in spite of good merits. In this paper, an ultrathin punch with a tapered shape and a cylindrical tip is newly fabricated by electrochemical process.

• 한국군사과학기술학회지
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• 제19권4호
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• pp.476-482
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• 2016

In this study, a method using single Wheatstone bridge flexure has been presented to measure hinge moment acting on control surfaces of wind tunnel models. The structural simplicity of the flexure reduces difficulty regarding gauging and wire-routing, and also makes it feasible to install flexures even inside thin wings. Some flexures were designed and fabricated under typical aerodynamic loads in wind tunnel test, and the strains on the flexure according to applied loads were compared with the result of the analysis by finite element method. The relation between applied loads and output signals showed good linearity, and the standard deviation on the residual errors from linear equation obtained by least square method was within 1.0 % of the maximum design moments. In addition, the FEM analysis on the thickness of load-connecting part of the flexure showed that the sensitivity was improved as the thickness became thin as much as desired to avoid buckling.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.723-726
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• 2002

We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-$\gamma$ Benzyl $_D$-Glutamate/Al; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 초전도 자성체 연구회
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• pp.30-33
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• 2003

YBCO coated conductor, also called the 2nd generation high temperature superconducting wire, consists of oxide multi-layer hetero-epitaxial thin films. Pulsed laser deposition (PLD) is one of many film deposition methods used to make coated conductor, and is the one known to be the best to make superconducting layer so far. As a part of the effort to make long length coated conductor, the optimum deposition condition of YBCO film on single crystal substrate (SrTiO3) was investigated using PLD. Substrate temperature, oxygen partial pressure, and laser fluence were varied to find the best combination to grow high quality YBCO film.

• Archives of Plastic Surgery
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• 제38권1호
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• pp.96-101
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• 2011

Purpose: In treatment of facial bone fracture, occurred in children, we generally use wires, miniplate, absorbable plate or their combination. These foreign bodies can be palpable, and sometimes may cause infections, and need reoperation for removing. When bone fragments are multiple, small or thin, they are hard to handle and make accurate reduction of all fragments. In these cases, a biodegradable tissue adhesive, Histoacryl$^{(R)}$ (n-butyl-2-cyanoacrylate), can be used as fixation technique for small, multiple, and thin fracture fragments. Methods: 3 years old and 6 years old children, who has comminuted fracture on frontal sinus, we used Histoacryl$^{(R)}$ for fixation of multiple bone fragments. After approaching by coronal incision, we pulled out all bone fragments and reconstructed bone fragments by Histoacryl$^{(R)}$ and fixed those on frontal sinus by absorbable plates. Results: Photographs and 3-dimensional CT obtained preoperatively and postoperatively. And we compared them each other in terms of accuracy of reconstructed bony contour. We could reconstruct almost all bone fragments easily along 3-dimensional structure and get excellent aesthetic results. There was no complication such as infection. Conclusion: In treatment of comminuted facial bone fracture, occurred in children, Histoacryl$^{(R)}$ is an excellent method for accurate reconstruction in small and thin bone fragments which cannot be fixed by wire, miniplate or absorbable plate without complication.

• 터널과지하공간
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• 제25권3호
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• pp.293-302
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• 2015

박층 뿜칠 라이너(TSL)는 숏크리트와 철망을 대체하는 새로운 암반 지보재로서 고려되고 있다. 하지만 아직까지 TSL의 핵심 제작기술이 공개되지 않은 관계로 독자적인 TSL 개발이 요구되고 있다. 따라서 본 연구에는 TSL의 개발을 위한 첫 번째 단계로서, 2가지의 경제적인 분말형 TSL 시작품 배합조건들을 도출하였고 이들을 액상 및 분말 재료가 혼합되는 2성분 외국산 TSL의 역학적 성능들과 실험적으로 비교하였다. 실험결과, 1가지 TSL 시작품 배합조건은 파괴 시의 신장률이 낮게 나타나 지보재로서의 활용이 어려운 것으로 나타났으나, 나머지 TSL 시작품 배합조건은 기존 외국산 TSL보다 큰 인장강도와 부착강도를 발현하는 등 우수한 성능을 나타내었으며 유럽 EFNARC(2008)의 모든 성능기준을 만족하여 지보재로서 활용이 가능한 것으로 검증되었다. 단, 외국산 2성분 TSL과 비교할 때 TSL 시작품의 연성을 추가적으로 향상시키기 위한 보완이 필요한 것으로 나타났다.