• 한국전기전자재료학회논문지
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• 제28권12호
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• pp.821-825
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• 2015

Anti-reflective (AR) thin film was fabricated on a glass substrate by sol-gel method. The coating solution was synthesized with TEOS (tetraethlyorthosilicate) and poly ethylene glycol (PEG, 4.0 wt%). As the withdrawal speed of coating was changed from 0.1 mm/sec to 0.3 mm/sec, the thickness and refractive index of prepared thin films were changed. The reflectance and transmittance of coating glass fabricated by the withdrawal speed of 0.1 mm/sec were 0.62% and 95.0% in visible light range. The refractive index and thickness of single layer thin film were n= 1.29 and ca. 99.0 nm.

• 한국표면공학회지
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• 제31권2호
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• pp.81-90
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• 1998

NiCrAly/YSZ(8wt% Y2O3-Zro2) functionally fraded thermal barrier coating (FGC) layers on a Co-base sureralloy (HAYNESS 188) substrate were fabricated using Ar shielded single torch air plasma spraying method. Functional grading were produced with the stepwise compositional change throughout layer thinkness. Microstructural observation revealed a sucessful fabrication of NiCrAly/YSZ FGC. From the results of the curvature measurement, adhesive stength measurement and thermal shock test for the FGC, it was concluded that the optimum enhance of functionally graded coating layer thinkcess and compositional pattern exit to enhance the properties of FGC, which is closely reated to the internal residual distribution with it.

• 한국표면공학회지
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• 제48권5호
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• pp.218-226
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• 2015

The goal of this study is to investigate a metal cladding that contains SiC composites as a protective layer and analysis the characteristics of the specimens on high temperature oxidation To make SiC composites, the current process needs a high temperature (about $1100^{\circ}C$) for the infiltration of fixing materials such as SiC. To improve this situation, we need a low temperature process. In this study, we developed a low temperature process for making SiC composites on the metal layer, and we have made two kinds: cladding with protective SiC composites made by polycarbosilane(PCS), and a PCS filling method using supercritical carbon dioxide. A corrosion test at $1200^{\circ}C$ in a mixed steam and Ar atmosphere was performed on these specimens. The result show that the cladding with protective SiC composites have excellent oxidation suprression rates. This study can be said to have developed new metal cladding with enhanced durability by using SiC composite as protective films of metal cladding instead of simple coating film.

• 한국표면공학회지
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• 제48권5호
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• pp.205-210
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• 2015

NbN coatings were prepared by ICP (inductively coupled plasma) assisted magnetron sputtering from a Nb metal target in $Ar+N_2$ atmosphere at various ICP powers. Effect of ICP on the microstructure, crystalline structure and mechanical properties of NbN coatings was investigated by field emission electron microscopy, X-ray diffraction, atomic force microscopy and nanoindentation measurements. The results show that ICP power has a significant influence on coating microstructure, structure and mechanical properties of NbN coatings. With the increasing of ICP power, coating microstructure evolves from the columnar structure of DC process to a highly dense one. Crystalline structure of NbN coatings were changed from cubic ${\delta}$-NbN to hexagonal ${\beta}-Nb_2N$ with increase of ICP power. The maximum nano hardness of 25.4 GPa with Ra roughness of 0.5 nm was obtained from the NbN coating sputtered at ICP power of 200 W.

• 대한금속재료학회지
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• 제50권9호
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• pp.653-657
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• 2012

In this study, a molybdenum disilicide ($MoSi_2$) coating process was investigated by hydrogen reduction and Si-pack cementation. At first, the metallic Mo coating was carried out by hydrogen reduction of $MoO_3$ powder at $750^{\circ}C$ for various holding times (1, 2, 3 h) in hydrogen atmosphere. A $4.3{\mu}m$ thick metallic molybdenum thin film was formed at 3 h. $MoSi_2$ was obtained by Si-pack cementation on molybdenum thin film through hydrogen reduction processing. It was carried out using $Si:Al_2O_3:NH_4Cl=5:92:3$ (wt%) packs at $900^{\circ}C$ for various holding times (30, 60, 90 min) in Ar atmosphere. When the holding time was 90 min, a $MoSi_2$ layer was coated successfully and a $15.4{\mu}m$ thickness was observed.

• 한국표면공학회지
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• 제34권2호
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• pp.97-104
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• 2001

($Ti_{ 1-x}$$Al_{ x}$)N has been deposited on high speed steel (HSS) substrate using PECVD from the gas mixture of $TiC1_4$, $AlC1_4$, $NH_3$, $H_2$, and Ar. The correlation between the microstructure and the mechanical properties was investigated. ($Ti_{1-x}$$Al_{ x}$)N showed single phase NaCl-structure up to X=0.87, while a mixed phase of NaCl Type (Ti, Al) N and wurtzite structure AlN was observed for 0.87$Ti_{1-x}$ $Al_{x}$ )N became by degrees as increasing X, which made the hardness of the coating higher by Al addition. When the coating was composed of a mixed phase, however, the hardness decreased abruptly due to the effect of soft AlN phase. The wear volume of the coatings could be obtained as the concentration of the coating was varied, and the relation between the wear volume and hardness or the adhesion strength was discussed.

• 전자공학회논문지A
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• 제32A권11호
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• pp.44-51
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• 1995

Homogeneous, compositionally graded, and superlattice-like silicon oxynitride(SiON) dielectric layers, with the refractive index varying from 1.46 to 2.05 as a function of film thickness, were grown by computer-controlled plasma-enhanced chemical vapor deposition (PECVD) using silane, nitrogen, and nitrous oxide reactant gases. An antireflection(AR) coating and thin-film electroluminescent(TFEL) devices with multiple dielectrics were designed and fabricated using real time control of reactant gases of the PECVD system.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.128-128
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• 2012

Korea institute of materials science (KIMS) has researched an anode layer linear ion source (ALIS) for various roll-to-roll treatment processes. The ALIS can be used to Ar ion beam (1~2 keV) treatment, and diamond-like carbon coating and so on. The treatment width of ALIS is 500 mm with a uniformity below 5 % (=(Max-min)/(Max+min)). We also demonstrate the status of development of ALIS in a roll-to-roll industry.

• 한국산학기술학회논문지
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• 제13권9호
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• pp.4139-4145
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• 2012

본 논문에서는 향후 태양전지 반사방지막에 적용여부를 알기 위하여 굴절률 분포에 따른 반사방지막의 성능을 분석하였다. 기존논문에서 제시되었던 1차, 3차 및 5차 함수의 굴절률 분포를 6층 구조의 두께 180 nm 반사방지막에 적용하고 각 굴절률 분포에 대한 반사율을 계산하고 비교하였다. 또한 새로운 구배형 굴절률(graded index) 구조를 제안하였고, 제안한 구조와 기존의 1차, 3차 및 5차 함수의 반사율과 비교하였다. 그 결과로써, 굴절률 분포가 고차 함수로 갈수록 반사율이 대체적으로 감소하였고, 구배형 굴절률 분포의 경우는 짧은 파장대(500 nm ~ 700 nm 이하)에서는 1차, 3차 및 5차 함수보다 더 높은 반사율을 보였고, 긴 파장대(700 nm 이상 ~ 800 nm)에서는 더 낮은 반사율을 보였다. 따라서 긴 파장대에서는 구배형 굴절률 분포가 기존의 1차, 3차, 5차 함수인 경우보다 더 좋은 반사방지막이 될 수 있다는 것을 발견했고, 이 결과는 긴 적색 가시광선에서 적외선 영역에 적용되는 광소자 및 광필터에 적용 가능하리라 판단된다.

• 한국표면공학회지
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• 제51권4호
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• pp.224-230
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• 2018

In this study, Mg films were prepared on hot dip aluminized steel (HDA) by using a sputtering method as a high corrosion resistance coating. The corrosion resistance of the Mg films was improved by controlling the morphology and the crystal structure of films by adjusting the Ar gas pressure during the coating process. Anodic polarization measurement results confirm that the corrosion resistance of the Mg films was affected by surface morphology and crystal structure. The corrosion resistance of the Mg coated HDA specimen increased with decreasing crystal size of the Mg coating and it was also improved by forming a film with denser morphology. The crystal structure oriented at Mg(101) plane showed the best corrosion resistance among crystal planes of the Mg metals, which is attributed to its relatively low surface energy. Neutral salt spray test confirmed that corrosion resistance of HDA can be greatly improved by Mg coating, which is superior to that of HDG (hot dip galvanized steel). The reason for the improvement of the corrosion resistance of Mg films on hot dip aluminized steel was due to the barrier effect by the Mg corrosion products formed by the corrosion of the Mg coating layer.