• 한국세라믹학회지
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• 제51권5호
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• pp.447-452
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• 2014

This paper presents the effects of pulse plasma parameters such as duty cycle and pulse frequency on the properties of TiAlN coatings deposited by asymmetric bipolar pulsed DC magnetron sputtering systems. The results show that, with decreasing duty cycle and increasing pulse frequency, the coating morphology changes from a columnar structure to a dense structure with finer grains. Pulsed sputtered TiAlN coatings showed higher hardness, higher residual stress, and smaller grain sizes than did DC prepared TiAlN coatings. Moreover, residual stress and nanoindentation hardness of pulsed sputtered TiAlN coatings increased with increasing pulse frequency. Meanwhile, the surface roughness decreased continuously with increasing pulsed DC frequency up to 50 kHz.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.101.1-101.1
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• 2015

플라즈마에 의한 식각 공정중 챔버 내에서 발생한 오염입자가 기판위에 떨어져 제품의 불량을 일으키고 그에 따른 부품 교체비용이나 교체시 가동을 멈춰야하는 문제점들이 있다. 이러한 문제점을 해결하기 위해 내플라즈마성이 우수하다고 알려진 아노다이징 피막을 사용하고 있다. 하지만 다양한 아노다이징 공법중 어떠한 요인이 내플라즈마 특성과 관계되는지에 대한 보고는 부족한 실정이다. 기존의 아노다이징 특성평가방법으로는 내화학 특성과 열안정성 평가, 구조적 특성을 확인하는 것이 주로 사용되어 왔다. 따라서 본 연구에서는 기존 내화학 특성과 열안정성이 우수하다고 알려진 황산-주석산법을 이용한 피막의 특성을 평가하여 내화학특성, 열적 안정성, 구조적 특성이 내플라즈마 특성과 어떠한 관계가 있는지 확인했다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.56-59
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• 2000

In this study, Ferroelectric $Pb(Zr_x,Ti_{1-x})O_3$(x=0.53) thin films were fabricated by the spin-coating on the Pt/Ti/$SiO_2$/Si substrate using the PZT metal alkoxide solutions with various excess Pb contents. Etching of PZT film was performed using planar inductively coupled Ar(20)$/Cl_2/BCl_3$ plasma. The etch rate of PZT film was 2450 ${\AA}/min$ at Ar(20)$/BCl_3$(80) gas mixing ratio and substrate temperature of $80^{\circ}C$. The leakage current densities of before etching and after etching PZT thin film were $6.25\times10^{-8}A/cm^2$, $8.74\times10^{-7}A/cm^2$ with electric field of 0.07MV/em, respectively.

• 한국주조공학회지
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• 제18권6호
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• pp.593-603
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• 1998

Commercial ductile iron was coated with titanium and aluminum powders by low pressure plasma spraying and then irradiated with a $CO_2$ laser to produce anti-corrosive TiC composite layer. TiC carbides were precipitated homogeneously in a laser alloyed layer by in-situ reaction between carbon existed in the base metal and titanium with thermal sprayed coating. The formation of gas pores and brittle limited mixing zone with ledeburite microstructure in TiC composite layer were surpressed by the complementary alloying of aluminum. The hardness of TiC composite layer obtained by addition of titanium and aluminum was between 600 and 660 Hv, which was three times as high as the hardness of ferritic ductile iron. From the results of isothermal oxidation at 1123k for 24 hours in air, high temperature oxidation resistance of the TiC composite layer with aluminum was improved and doubled when compared with the TiC composite layer without aluminum.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.964-967
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• 2002

The effectiveness of silicon nitride SiNx surface passivation is investigated and quantified. This study adopted single-layer antireflection (SLAR) coating of SiNx for efficiency improvement of solar cell. The silicon nitride films were deposited by means of plasma enhanced chemical vapor deposition (PECVD) in planar coil reactor. The process gases used were pure ammonia and a mixture of silane and helium. The thickness and the refractive index on the films were measured by ellipsometry and chemical bonds were determined by using an FT-IR equipment. This films obtained were analyzed in term of hydrogen content, refractive index for gas flow ratio $(NH_3/SiH_4)$, and efficiency of solar cell. The polycrystalline silicon solar cells passivated by silicon nitride shows efficiency above 12.8%.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.97-107
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• 1998

Three different kinds of brake discs including two coated brake discs and one steel disc were tested under the same experimental conditions on a reduced scale braking test bench. Braking test bench was specially designed to analyse thermo-mechanical and frictional behaviors of two sizes of brake discs in stop and hold braking modes. And Plasma spray coating technique was used to coat ceramic powder on the discs. In the test four commercial brake pads were coupled with discs. Ceramic coated discs had shown good stability in friction coefficient at high speed and high energy braking conditions. But they caused large pad mass wear loss compared with the steel disc. It was shown that thermal barrier effect in ceramic coated discs adjusted the thermal partition between pad and disc. For a steel disc, it had shown fluctuating friction coefficient at high speed but a fittie pad mass wear loss compared with ceramic coated discs.

• Transactions on Electrical and Electronic Materials
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• 제8권3호
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• pp.125-130
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• 2007

DLC coating on ceramics is very useful for manufacturing the materials with hardness and low friction. Adhesion of DLC thin film on ceramics, on the other hand, is usually very weak. Adhesion of DLC film depends on many parameters such as contamination and chemical bonding between thin film and substrate. In this study, adhesion of DLC film on ceramics was improved by the intermediate layer when the plasma immersion ion deposition (PIID) technique was applied. It is found that the chemical composition and the thickness of intermediate layer have significantly an effect on the adhesion of DLC thin film on $Al_2O_3$.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.314-315
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• 2004

As environmental issue threatens to be aggravated, applications of bio-degradable plastic (Polybutylene Succinate:PBS) tend to be increased. However, improvement of mechanical characteristics of PBS is indispensable for further widespread actual applications. Therefore, in order to produce further functional P8S with improved mechanical characteristics, TiO$_2$ coatings on PBS substrate were prepared under various spraying conditions using plasma and HVOF spraying techniques. The effects of thermal spraying methods and spraying parameters on coating properties could be confirmed. Moreover, wear behavior for TiO$_2$ coatings on PBS substrate has been also reviewed and characterized.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.516-517
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• 2010

최근에 들어 반도체 및 디스플레이 분야를 포함하여 태양전지와 같은 신재생 에너지 분야에서 고품질, 고기능성 박막이 많이 사용되고 있으며, 이에 따라 플라즈마 제어기술 및 코팅 공정기술 개발에 대한 요구가 증가하고 있다. 산업기술이 고도화됨에 따라 다양한 계열의 박막이 필요하게 되었고 고밀도의 플라즈마를 공급하고 안정된 공정을 진행하기 위해 순시적인 플라즈마 제어가 가능한 임펄스 전원장치에 대한 연구가 활발히 진행되고 있다. 기존의 임펄스 전원장치에서는 플라즈마 발생에 필요한 고전압 발생만 관점을 두고 있으나 플라즈마의 발생뿐이 아니라 증착율이 높은 상태로 유지되어야 실제 공정의 효율이 증가한다. 본 연구에서는 증착 효율을 극대화하기 위하여 별도의 저압회로를 부가한 복합형 임펄스 전원장치를 제안한다.

• 한국산학기술학회논문지
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• 제4권4호
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• pp.361-365
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• 2003

Oxide etcher장비에서 실리콘 웨이퍼를 잡고 공정을 수행할 수 있는 단극 (unipolar) 형태의 E-chuck을 제작하였다. 단극 형태의 E-chuck을 개발하기 위하여 핵심기술인 폴리이미드 박막의 코팅기술과 알미늄 표면의 양극처리기술을 개발하였다. E-chutk은 폴리이미드 재료를 표면 물질로 사용하여 플라스마에 의한 표면 손상을 최소화하였다. Oxide etcher 장비에 사용되는 핵심 부품인 E-chuck의 제조 과정을 살펴보고 히터 내장형 E-chuck을 위한 박막형 전열체 기술을 개발하였다.