• E2M - 전기 전자와 첨단 소재
• /
• 제11권10호
• /
• pp.24-31
• /
• 1998

Interfacial effect in polymetric composites have been studied extensively. This report deals mainly with the effects of interfacial space charge and interface structure. A model for the dynamic process of interfacial space charge accumulation is proposed. The new model might interpret some interface phenomena which is difficult to be explained in terms of traditional Maxwell-Wagner theory. An interface structure is also presented, by which the importance of surface treatment of glass Fiber for improving the properties of FRP could be well understood.

• 한국염색가공학회지
• /
• 제10권2호
• /
• pp.8-17
• /
• 1998

In this study we have examined electroless chemical plating on the plasma grafted poly [ethylene terephathalate］(PET) fabric in order to improve the interfacial adhesion between metal and fiber. The vapour phase of acrylic acid introduced on the PET surface and the graft polymerization was carried out by using cold plasma, resulting in the grafting yield of 0.8-1.3 wt％. The carboxyl group of the plasma grafted was identified by FT-IR-ATR spectra. The Interfacial adhesion was related to the carboxyl group. After electroless chemical plating of nickel, it showed that the more the carboxyl, the better the interfacial adhesion. Comparing to the untreated, the plasma grafted fabric showed fairly good interfacial adhesion(5B grade, ASTM D3359) . The shielding effect of electromagnetic wave showed 95dB. The shielding effect depends on the fabric structure, the surface structure, and the cross sectional shape of fibers. The dense fabric structure, the etched surface like a microcrater, and the trigonal cross sectional shape were prefered.

• 소음진동
• /
• 제8권6호
• /
• pp.1093-1102
• /
• 1998

The success of controllability of smart structures depends on the quality of the bonding along the interface between the main structure and the attached sensing and acuating elements. Generally, the analysis procedures neglect the effect of the interfacial bond layer or assume that this bond layer behaves like viscoelastic material. Three different bond layers. two modified epoxy adhesives, and one isocyanate adhesive were prepared for their toughness and moduli. Bond layer of the chosen adhesive provides an almost perfect bonding condition between the composite structure and the PZT while bended significantly like arrow-shape. The perfect bonding condition is tested by considering various material properties of the bond layers. and based on this perfect bonding condition, the effects of the interfacial bond layer on the dynamic behavior and controllability of the test structure is experimentally studied. Once the perfect bonding condition is achieved. dynamic effects of the bond layer itself on the dynamic characteristics of the main structure is negligible. but the contribution of the attached PZT elements on the stiffness of the multi-layered structure becomes significant when the thickness of the bond layer increased.

• 마이크로전자및패키징학회지
• /
• 제8권2호
• /
• pp.15-18
• /
• 2001

Magnetron sputtering 장비를 이용하여 극자외선 노광 공정용 Mo/Si 다층 박막을 증착하였다. 증착 파워로는 Mo의 경우 DC파워를, Si의 경우 RF파워를 이용하였다. 각각의 target에 인가되는 DC 또는 RF 파워의 시간 및 파워 조절을 통해서 원하는 구조인자를 가진 다층박막을 증착하였다. 증착된 다층박막을 단면 TEM, low/high angle XRD 등을 이용하여 박막의 미세구조와 interfacial layer의 거동을 살펴 보았으며, low angle XRD로부터 다층박막을 간접적으로 평가할 수 있었으며, 단면 TEM으로부터 Si위에 형성되는 Mo의 interfacial layer가 Mo위에 형성되는 경우보다 두꺼운 것을 알 수 있었다.

• Transactions on Electrical and Electronic Materials
• /
• 제15권6호
• /
• pp.328-332
• /
• 2014

Thin film transistors (TFTs) with an amorphous silicon zinc tin oxide (a-2SZTO) channel layer have been fabricated using an RF magnetron sputtering system. The effect of the change of excitation electron on the variation of the total interfacial trap states of a-2SZTO systems was investigated depending on sputtering power, since the interfacial state could be changed by changing sputtering power. It is well known that Si can effectively reduce the generation of the oxygen vacancies. However, The a-2SZTO systems of ZTO doped with 2 wt% Si could be degraded because the Si peripheral electron belonging to a p-orbital affects the amorphous zinc tin oxide (a-ZTO) TFTs of the s-orbital overlap structure. We fabricated amorphous 2 wt% Si-doped ZnSnO (a-2SZTO) TFTs using an RF magnetron sputtering system. The a-2SZTO TFTs show an improvement of the electrical property with increasing power. The a-2SZTO TFTs fabricated at a power of 30 W showed many of the total interfacial trap states. The a-2SZTO TFTs at a power of 30 W showed poor electrical property. However, at 50 W power, the total interfacial trap states showed improvement. In addition, the improved total interfacial states affected the thermal stress of a-2SZTO TFTs. Therefore, a-2SZTO TFTs fabricated at 50 W power showed a relatively small shift of threshold voltage. Similarly, the activation energy of a-2SZTO TFTs fabricated at 50 W power exhibits a relatively large falling rate (0.0475 eV/V) with a relatively high activation energy, which means that the a-2SZTO TFTs fabricated at 50 W power has a relatively lower trap density than other power cases. As a result, the electrical characteristics of a-2SZTO TFTs fabricated at a sputtering power of 50 W are enhanced. The TFTs fabricated by rf sputter should be carefully optimized to provide better stability for a-2SZTO in terms of the sputtering power, which is closely related to the interfacial trap states.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.65-69
• /
• 2002

An Al film deposited on the Kovar alloy substrate was anodically-bonded to the borosilicate glass, and the bond interfaces was closely investigated by transmission electron microscopy. Al oxide was found to form a layer ~l0 nm thick at the bond interface, and fibrous structure of the same oxide was found to grow epitaxially in the glass from the oxide layer. The fibrous structure grew with the bonding time. The mechanism of the formation of this fibrous structure is proposed on the basis of the migration of Al ions under the electric field. Penetration of Al into glass beyond the interfacial Al oxide was not detected. The comparison of the amount of excess oxygen ions generated in the alkali depletion layer with that incorporated in the Al oxide suggests that the growth of the alkali-ion depletion layer is controlled by the consumption of excess oxygen to form the interfacial Al oxide.

• 한국세라믹학회지
• /
• 제33권12호
• /
• pp.1421-1425
• /
• 1996

Sintered Si3N4 and Inconel composed of Ni(58-63%) Cr(21-25%) Al(1-17%) Mn(<1%) fe(balance) were pressurelessly joined by using Ag-Cu-Ti brazing filler metal at 950℃ and 1200℃ under N2 gas atmosphere of 1atm and their interfacial structures were investigated. In case that the reaction temperature was low as 950℃ its interfacial structure was "Inconel metal/Ti-rich phase layer/brazing filler metal layer/Si3N4 " Ti used as reactive metal existed in between inconel steel and brazing metal and moved to the interface of between brazing filler metal nd Si3N4 according as reaction temperature increased up to 1200℃. The interfacial structure of inconel steel-Si3N4 reacted at 1200℃ was ' inconel metal/Ni-rich phase layer containing of Fe. Cr and Si/Cu-rich phase layer containing of Mn and Si/Si3N4 " Cr Mn, Ni and Fe diffused to the interface of between brazing filler metal and Si3N4 and reacted with Si3N4 The most reactive components of ingredients of inconel metal were Cr and Mn. On the other hand Ti added as reactive components to Ag-Cu eutectic segregated into Ni-rich phase layer,.

• 마이크로전자및패키징학회지
• /
• 제27권3호
• /
• pp.41-47
• /
• 2020

비메모리 반도체 미세 Cu배선의 전기적 신뢰성 향상을 위해 SiN_x 피복층(capping layer)과 Cu 배선 사이 50 nm 두께의 Co 박막층 삽입이 계면 신뢰성에 미치는 영향을 double-cantilever beam (DCB) 접착력 측정법으로 평가하였다. DCB 평가 결과 SiN_x/Cu 구조는 계면접착에너지가 0.90 J/㎡이었으나 SiN_x/Co/Cu 구조에서는 9.59 J/㎡으로 SiN_x/Cu 구조보다 약 10배 높게 측정되었다. 대기중에서 200℃, 24시간 동안 후속 열처리 진행한 결과 SiN_x/Cu 구조는 0.93 J/㎡으로 계면접착에너지의 변화가 거의 없는 것으로 확인되었으나 SiN_x/Co/Cu 구조에서는 2.41 J/㎡으로 열처리 전보다 크게 감소한 것을 확인하였다. X-선 광전자 분광법 분석 결과 SiN_x/Cu 도금층 사이에 Co를 증착 시킴으로써 SiN_x/Co 계면에 CoSi₂ 반응층이 형성되어 SiN_x/Co/Cu 구조의 계면접착에너지가 매우 높은 것으로 판단된다. 또한 대기중 고온에서 장시간 후속 열처리에 의해 SiN_x/Co 계면에 지속적으로 유입된 산소로 인한 Co 산화막 형성이 계면접착에너지 저하의 주요인으로 판단된다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
• /
• pp.897-899
• /
• 1999

In this paper, the interfacial dielectric breakdown phenomenon of interface between Epoxy/EPDM (ethylene propylene diene terpolymer) was discussed, which affects stability of insulation system of power delivery devices. Specimen structure was designed by using MAGSOFT's FLUX2D based on the finite elements method. Design concepts is to reduce the effect of charge transport from electrode in the process of breakdown and to have the tangential electrical potential with the Epoxy/EPDM interface. AC interfacial breakdown phenomenon of was investigated by variation of interfacial conditions oil and temperature which are supposed to have influence on the interfacial breakdown strength. Interfacial breakdown strength was improved by spreading oil over interfacial surface. The decreasing ratio of the AC interfacial breakdown strength in non-oiled specimens was increased by the temperature rising and its of oiled specimens was not affected by temperature.

• Nuclear Engineering and Technology
• /
• 제37권6호
• /
• pp.525-536
• /
• 2005

The interfacial area transport equation dynamically models the changes in interfacial structures along the flow field by mechanistically modeling the creation and destruction of dispersed phase. Hence, when employed in the numerical thermal-hydraulic system analysis codes, it eliminates artificial bifurcations stemming from the use of the static flow regime transition criteria. Accounting for the substantial differences in the transport mechanism for various sizes of bubbles, the transport equation is formulated for two characteristic groups of bubbles. The group 1 equation describes the transport of small-dispersed bubbles, whereas the group 2 equation describes the transport of large cap, slug or chum-turbulent bubbles. To evaluate the feasibility and reliability of interfacial area transport equation available at present, it is benchmarked by an extensive database established in various two-phase flow configurations spanning from bubbly to chum-turbulent flow regimes. The geometrical effect in interfacial area transport is examined by the data acquired in vertical fir-water two-phase flow through round pipes of various sizes and a confined flow duct, and by those acquired In vertical co-current downward air-water two-phase flow through round pipes of two different sizes.