• 대한전기학회논문지:시스템및제어부문D
• /
• 제52권5호
• /
• pp.206-206
• /
• 2003

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

• 대한전기학회논문지:전기물성ㆍ응용부문C
• /
• 제52권5호
• /
• pp.206-212
• /
• 2003

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

• 마이크로전자및패키징학회지
• /
• 제30권1호
• /
• pp.49-54
• /
• 2023

최근 SIP (System in Packaging) 기술은 고주파(5G 이상) 통신 및 미세 피치 회로 특성을 만족해야 한다. 기존 ENIG (Electroless Ni/Immersion Au Plating) 표면처리는 전송 손실이 증가하여 고주파에 적합하지 않으므로, 니켈 도금층이 없어도 패턴 및 패드의 신뢰성 수준을 만족시킬 수 있는 표면 처리 기술이 검토되고 있다. 본 논문에서는 고주파 통신 대응을 위한 Ni-less 표면처리기술과 소재에 따른 주파수 특성 등에 대한 연구 동향을 조사하였다.

• 설비공학논문집
• /
• 제12권5호
• /
• pp.525-532
• /
• 2000

Evaporation heat transfer characteristics have been investigated experimentally when distilled water is sprayed on the outside wall of horizontal tubes in a evaporator. This problem is of particular interest in the design of evaporator of an absorption system. Hydrophilic surface treatment was employed to increase the wettability on copper tubes. The results indicate that evaporation heat transfer with hydrophilic tubes is shown to be 25-44% higher than that with bare tubes at evaporation pressure of 31.8 Torr(evaporation temperature$ 30^{\circ}C). Evaporation heat transfer rates of hydrophilic treatment tubes are improved substantially, comparing with those of conventional copper tubes in the wide range of operating parameters, such as water inlet temperatures, water mass flow rates and evaporation pressures.

• Transactions on Electrical and Electronic Materials
• /
• 제11권6호
• /
• pp.266-270
• /
• 2010

The effect of an Ar plasma treatment on polycarbonate substrates was investigated using $TiO_2$ coatings produced by reactive ion-beam assisted sputtering. The typical pressure used during sputtering was about $10^{-4}$ Torr. After the Ar plasma treatment, the contact angle of a water droplet was reduced from $88^{\circ}$ to $52^{\circ}$ and then further decreased to $12^{\circ}$ with the addition of oxygen into the chamber. The surface of the polycarbonate substrate hanged from hydrophobic to hydrophilic with these treatments and revealed its changing nano-scale roughness. The $TiO_2$ films on the treated surface showed various colors and periodic ordering dependant on the film thickness due to optical interference.

• 열처리공학회지
• /
• 제1권1호
• /
• pp.1-7
• /
• 1988

In this study the improvement of mechanical properties of ion-nitrided SACM-1 steel was investigated by analysing microstructural developments and hardness increase in the nitrided surface layer. Specimens were quenched at $570^{\circ}C$, which is lower than the eutectoid temperature ($590^{\circ}C$) of Fe-N binary system after nitrided at temperature of $460-570^{\circ}C$ for 2-8 hours under constant pressure of 8 torr. The depths of diffusion and compound layers were appeared to proportional to the root mean square time of nitriding. And the hardness showed the maximun value Hv = 1200 for the specimen nitrided at $530^{\circ}C$. Hardness distribution of the. ion-nitrided steels were increased by diffusion treatment below the eutectoid temperature of the Fe-N binary system. A prolonged heat treatment below the eutectoid temperature was attributed to the increase in the depth of diffusion layer at the expense of the decrease in surface hardness of the ion nitreded steel.

• 대한치과보철학회지
• /
• 제43권5호
• /
• pp.599-610
• /
• 2005

Purpose: The success of the bonding between electroformed gold and ceramic is dependent on the surface treatment of the pure gold coping. The purpose of this study was to evaluate the bonding strength between the electroformed gold and ceramic with varying surface treatment. Materials and methods: A total of 32 disks,8 were using conventional ceramometal alloy, 24 were using electroforming technique as recommended by manufacturer, were prepared. 24 electroformed disks were divided 3 groups according to surface treatment, i.e. 50 microns aluminium oxide sandblasting(GES-Sand), gold bonder treatment(GES-Bond) and $Rocatec^{TM}$ system(GES-Rocatec). For control group of conventional alloy 50 microns aluminium oxide treatment was done(V-Supragold). Energy dispersive x-ray analysis and scanning electron microscope image were observed. Using universal testing machine, shear bond strength and bonding failure mode at metal-porcelain interface were measured. Results and Conclusion: The following conclusions were drawn: 1. In the energy dispersive x-ray analysis, the Au was main component in electroformed gold(99.9wt%). After surface treatment, a little amount of $Al_2O_3(2.4wt%)$ were found in GES-Sand, and $SiO_2(4wt%)$ in GES-Bond. In GES-Rocatec, however, a large amount of $SiO_2(17.4wt%)$ were found. 2. In the scanning electron microscopy, similar pattern of surface irregu larities were observed in V-Supragold and GES-Sand. In GES-Bond, surface irregularities were increased and globular ceramic particles were observed. In GES-Rocatec, a large amount of silica particles attached to metal surface with increased surface irregularities were observed. 3. The mean shear bond strength values(MPa) in order were $22.9{\pm}3.7(V-Supragold),\;22.1{\pm}3.8(GES-Bond),\;20.1{\pm}2.8(GES-Rocatec)\;and\;13.0{\pm}1.4(GES-Sand)$. There was no significant difference between V-Supragold, GES-Bond, and GES-Rocatec. (P>0.05) 4. Most bonding failures modes were adhesive type in GES-Sand. However, in V-Supragold, GES-Bond and GES-Rocatec, cohesive and combination failures were commonly observed. From the result, with proper surface treatment method electroformed gold may have enough strength compare to conventional ceramometal alloy.

• 한국재료학회지
• /
• 제18권5호
• /
• pp.229-234
• /
• 2008

Porous Ti implant samples were fabricated by the sintering of spherical Ti powders in a high vacuum furnace. To increase their surface area and biocompatibility, anodic oxidation and a hydrothermal treatment were then applied. Electrolytes in a mixture of glycerophosphate and calcium acetate were used for the anodizing treatment. The resulting oxide layer was found to have precipitated in the phase form of anatase $TiO_2$ and nano-scaled hydroxyapatite on the porous Ti implant surface. The porous Ti implant can be modified via an anodic oxidation method and a hydrothermal treatment for the enhancement of the bioactivity, and current multi-surface treatments can be applied for use in a dental implant system.

• 접착 및 계면
• /
• 제12권1호
• /
• pp.26-33
• /
• 2011

폴리케톤 필름의 산처리 조건에 따른 필름 표면의 화학적인 변화를 접촉각과 XPS를 이용하여 분석하고, 모폴로지의 변화를 SEM과 AFM을 통하여 살펴보고, 최종적으로 이러한 변화가 폴리케톤 필름과 고무와의 계면접착력에 어떠한 영향을 미치는지를 살펴보았다. 인산처리에 의하여 폴리케톤 필름의 표면에 젖음성이 증가하여 인산의 농도 및 처리시간에 따라서 접촉각이 감소하였으며, 표면에 산소함유기들이 증가하는 결과를 보였다. 인산농도와 처리시간이 증가함에 따라 표면에 crack과 etching이 증가하여 표면거칠기가 증가하였으나, 산처리 조건이 강화되면서 폴리케톤 필름의 표면에 degradation이 발생하여 roughness가 감소하는 결과를 보였다. 폴리케톤과 고무와의 계면접착력을 살펴본 결과, pH 0.74에서 120 min, pH 0.4에서 60 min 처리한 경우에 최대 계면접착력을 보였으며, 산처리 조건이 그 이상으로 증가하면서 degradation이 발생하면서 계면접착력이 감소하였다.

• 한국전기전자재료학회논문지
• /
• 제22권1호
• /
• pp.81-85
• /
• 2009

We has been analysed optical properties of OLED(organic light emitting diode) and characteristics of ITO(Indium Tin Oxide) in terms of $O_2$ plasma treatment for manufacturing high efficiency OLED, RF power of $O_2$ plasma was changed 25, 50, 100, 200 W. $O_2$ gas flow, gas pressure and treatment time were fixed. Sheet resistance and surface roughness of ITO were measured by Hall-effect measurement system and AFM, respectively. The ranges of sheet resistance and surface roughness were $5.5{\sim}6,06\;{\Omega}$ and $2.438{\sim}3.506\;nm$ changing of RF power, respectively, PM(Passive Matrix)OLED was fabricated with the structure of ITO(plasm treatment)/TPD($400\;{\AA}$)/$Alq_3(600\;{\AA})$/LiF($5\;{\AA}$)/Al($1200\;{\AA}$). Turn-on voltage of PMOLED was 7 V and luminance was $7,371\;cd/m^2$ at the RF power of 25 W, $O_2$ plasma treatment of ITO surface was result in lowering the operating voltage and improving luminance of PMOLED.