• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.120.1-120.1
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• 2011

Increase the efficiency of PV modules for high-efficiency solar cells, light transmittance improvements, increasing the module, and much more research and development. Dual we light transmittance for photovoltaic module materials in low iron tempered glass in SiO2 using liquid AR implementation, light transmittance to solar modules to increase the efficiency of research.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.95-100
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• 2001

Recently, coated milling cutters are widely used for improving the productivity of cutting processes through high speed cutting and longer tool life. In metal cutting, cutting force increase rate is important factor to diagnose the cutting conditions because the amount of tool wear directly influences the cutting forces. As the cutting length increases, the worn cutter increases the cutting forces. In this study, the effect of coating process of end milling cutter on the cutting performance, especially on the cutting force increase rate, is investigated. The results acquired through the cutting test measuring cutting force increase rate show that not only the injection quantity of $N_2$ and Ar but also mean temperature influence the cutting force increase rate during the end milling process.

• Journal of Surface Science and Engineering
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• v.41 no.6
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• pp.287-291
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• 2008

Reactively magnetron sputtered TiN films were deposited on Si wafers under varying bias voltage and characterized by X-ray diffraction, field-emission scanning electron microscopy and Nanoindentation. The films deposited under an Ar + $N_2$ atmosphere exhibited a mixed (200)-(111) orientation with a strong (200) texture, which subsequently changed to a strong (111) texture with increasing bias voltage. The changes in texture and grain size of the TiN thin films are due to one or a combination of factors such as strain energy, surface free energy, surface diffusivity and adatom mobility. The influence of each factor depends on the processing conditions. The average deposition rate and grain size were calculated from FE-SEM images of the films indicating that the deposition rate was lower at the films deposited under bias voltage.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.95.1-95.1
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• 2017

In this study, it has been tried to make the single Mo-Cu alloying targets with the Cu showing the best surface hardness that was determined by investigation on the coatings with the double target process. The single alloying targets were prepared by powder metallurgy methods such as mechanical alloying and spark plasma sintering. The nanocomposite coatings were prepared by reactive magnetron sputtering process with the single alloying targets in $Ar+N_2$ atmosphere. The microstructure changes of the Mo-Cu-N coatings with diverse Cu contents were investigated by using XRD, SEM and EDS. The mechanical properties of the coatings were evaluated by using nano-indentor, scratch test, and ball on disc methods. Especially, the coated samples were tested by using various lubricating oil to compare the property of anti wear-resistance. In this study, the nano-composite MoN-Cu coatings prepared using an alloying target was eventually compared with the coatings from the multiple targets.

• Tribology and Lubricants
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• v.15 no.4
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• pp.328-334
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• 1999

Acoustic emission (AE) sensor was used to evaluate the wear-life of CrN-coated steel disks with 1 $\mu\textrm{m}$ and 4 $\mu\textrm{m}$ coating thickness. The relationship between Af and friction signal from scratch test and sliding test was investigated. The first spatting of CrN film was detected by AR signals in the early stage of coating failures, and overall failures by friction signals. Therefore, the conservative design for coating-life should be done using the results of AE signals. Using the percent contact load, the ratio of sliding normal load to the critical scratch load and the number of cycles to failure was measured to predict the wear-life of CrN film. On the wear-life dia-gram the percent contact loads and the number of cycles to failure showed a good linear relationship on the log coordinate. As the load percentage was decreased, the diagram showed that the wear-limits, at which the coated steels survived more than 35,000 cycles, were about 4∼5% of the critical scratch loads.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.226-226
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• 2014

난삭재에 대한 관심이 증가하면서 최근 공구시장에서는 고경도, 고내열성을 갖는 코팅물질에 대한 연구가 진행되고 있다. 따라서 두 장점을 모두 가진 나노복합구조를 가진 박막에 대한 연구가 진행되고 있으며 특히 경도에 영향을 미치는 나노결정립과 내열성에 영향을 주는 비정질층의 비율을 조절하는 연구에 집중하고 있다. 따라서 본 연구에서는 질소분압이 변화시키며 CrZrSiN 박막의 물성 변화를 확인하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.46-47
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• 2013

다이아몬드와 같은 $sp^3$ 결합을 가지며, 다이아몬드 다음으로 경도가 강한 입방정 질화붕소(cBN)는 철계금속가공에의 적합성 및 낮은 증착온도로 인하여 표면 코팅소재로의 응용이 크게 기대되어 왔다. 그러나 증착시 cBN 상의 핵생성 이전에 필연적으로 증착되는 비정질 질화붕소(aBN) 및 육방정 질화붕소(hBN) 층의 대기 하에서의 불안정성 그리고 cBN 상의 증착에 수반되는 높은 압축 잔류응력으로 인해 모재와의 밀착력이 낮아지는 문제점 등으로 인해 응용이 크게 제한되어져 왔다. 본 발표에서는 아르곤(Ar)과 질소($N_2$)를 반응가스로 이용하여 스퍼터링법으로 증착한 질화붕소에서 발생하는 높은 잔류응력의 원인과 이를 낮추기 위해 반응가스에 첨가한 수소의 효과에 대해서 상세히 고찰해 보고자 한다.

• Proceedings of the Optical Society of Korea Conference
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• 2000.08a
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• pp.26-27
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• 2000

고휘도 다이오드(Superluminescent Diodes : SLD)는 fiber gyroscope의 광원으로서 가장 적당한 소자로 알려져 있다$^{(1)}$ . 본 연구는 실제의 광섬유 자이로 스코프에 적용하기 위하여 활성층의 발진파장이 1.55$mu extrm{m}$인 SLD의 제작을 목적으로 하고 있다. SLD제작의 핵심은 거울면에서의 반사도를 낮추어 거울면의 반사에 의하여 일어나는 발진을 억제하는 것으로, 이를 위하여 단면이 각을 가진 stripe$^{(2)}$ , 계면의 무반사 코팅(antireflection coating : AR coating)$^{(3)}$ , window buried heterostructure$^{(4)}$ , unpumped absorbing region$^{(5)}$ , bent-buried absorbing region$^{(6)}$ 등과 같은 방법이 이용이 되고 있다 (중략)

• Journal of Surface Science and Engineering
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• v.34 no.4
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• pp.337-341
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• 2001

TiN coating of high speed end mill is recently generalized. The study of coating layer using ion plating is mainly about the coating method and the why of the longer life of coated tools. In CNC machning process, metal cutting isn't carry out until the tools including the end-mill and so on are fractured. Namely, it is difficult precision processing when the cutting force of the cutting tool is near the limit the fracture cutting force. So, the estimate of the life by wear and fracture is important. Therefore, this study is about the method to estimate the capacity of the coating layer in relation to the tendency of cutting force and the influence of the cutting capacity of coated end-mill by the condition N2, Ar, temperature. The cutting length is in inverse proportion to the cutting force ratio. So, the life of the TiN coated end mill can be predicated by the ratio of the increase of the cutting force.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1089-1091
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• 2004

본 연구에서는 fiexible 기판에 e-beam으로 sio2를 증착 한 후 R.F 스퍼터링으로 ito 박막을 증착한 경우와 polyimide를 스핀 코팅한 후 ito를 증착한 경우로 나누어서 실험 하였다. SIO2 박막은 ITO증착을 위해 증착온도 $100^{\circ}C$에서 증착 하였으며 ITO 박막은 투과율을 향상 시키기 위해서 Ar/O2 혼합가스를 이용하였다. SIO2 와 ITO 박막의 두께는 각각 500nm, 200nm로 증착하였다. Stress 분포는 bending test를 통해 발생하는 island의 crackt 수로 측정 하였다. 그 결과 crack 분포는 buffer layer의 young's modulus 크기와 island density 영향이 지배적임을 확인 하였다.