• 제목/요약/키워드: Reaction barrier

검색결과 321건 처리시간 0.045초

A Study on Bumping of Micoro-Solder for Optical Packaging and Reaction at Solder/UBM interface (광패키징용 마이크로 솔더범프의 형성과 Contact Pad용 UBM간의 계면 반응 특성에 관한 연구)

  • Park, Jong-Hwan;Lee, Jong-Hyun;Kim, Yong-Seog
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.332-336
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    • 2001
  • In this study, the reaction at UBM(Under Bump Metallurgy) and solder interface was investigated. The UBM employed in conventional optical packages, Au/Pt/Ti layer, were found to dissolve into molten Au-Sn eutectic solder during reflow soldering. Therefore, the reaction with different diffusion barrier layer such as Fe, Co, Ni were investigated to replace the conventional Pt layer. The reaction behavior was investigated by reflowing the solder on the pad of the metals defined by Cr layer for 1, 2, 3, 4, and 5 minutes at $330^{\circ}C$. Among the metals, Co was found to be most suitable for the diffusion barrier layer as the wettability with the solder was reasonable and the reaction rate of intermetallic formation at the interface is relatively slow.

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A Study on Bumping of Micro-Solder for Optical Packaging and Reaction at Solder/UBM interface (광패키징용 마이크로 솔더범프의 형성과 Contact Pad용 UBM간의 계면 반응 특성에 관한 연구)

  • 박종환;이종현;김용석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.332-336
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    • 2001
  • In this study, the reaction at UBM(Under Bump Metallurgy) and solder interface was investigated. The UBM employed in conventional optical packages, Au/Pt/Ti layer, were found to dissolve into molten Au-Sn eutectic solder during reflow soldering. Therefore, the reaction with different diffusion barrier layer such as Fe, Co, Ni were investigated to replace the conventional R layer. The reaction behavior was investigated by reflowing the solder on the pad of the metals defined by Cr layer for 1, 2, 3, 4, and 5 minutes at 330$^{\circ}C$. Among the metals, Co was found to be most suitable for the diffusion barrier layer as the wettability with the solder was reasonable and the reaction rate of intermetallic formation at the interface is relatively slow.

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Inactivation of Zooplankton Artemia sp. Using Plasma Process (플라즈마 공정을 이용한 동물성 플랑크톤 Artemia sp. 불활성화)

  • Dong-Seog Kim;Young-Seek Park
    • Journal of Environmental Science International
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    • 제32권3호
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    • pp.197-204
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    • 2023
  • This study aims to inactivate Artemia sp. (Zooplankton) in ballast water through the dielectric barrier discharge (DBD) plasma process. The DBD plasma process has the advantage of enabling direct electric discharge in water and utilizing chemically active species generated by the plasma reaction. The experimental conditions for plasma reaction are as follows; high voltage of 9-22 kV, plasma reaction time of 15-600 s, and air flow rate of 0.5-5.5 L/min. The results showed that the optimal experimental conditions for Artemia sp inactivation were 16 kV, 60 s, 2.5 L/min, respectively. The concentrations of total residual oxidants and ozone generated by plasma reaction increased with an increase of in voltage and reaction time, and the concentration of generated air did not increase above a certain amount.

Effect of Reducing Inflammation of Coptis chinensis Extract -Ceramide Complex through ECS Control in Atopic Dermatitis

  • Ahn, Sang Hyun;Kim, Ki Bong
    • The Journal of Korean Medicine
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    • 제42권4호
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    • pp.197-207
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    • 2021
  • Objectives: The purpose of this study was to confirm effect of reducing inflammation of Coptis chinensis extract-ceramide complex through the endocannabinoid system (ECS) control in atopic dermatitis. Methods: 8-week-old ICR mice were divided into normal group (Ctrl), lipid barrier elimination group (ADE), palmitoylethanolamide treated group after lipid barrier elimination (PEAT), and Coptis chinensis extract-ceramide complex applied group after lipid barrier elimination (CRA). After inducing atopic dermatitis, cannabinoid receptor (CB) 1, CB2, CD68, p-I𝜅B, iNOS, substance P and serotonin were observed to confirm the regulation of the ECS, macrophage activity and mast cell activity. Results: CB1 and CB2 showed higher positive reactions in the CRA than in the ADE and PEAT. CD68, p-I𝜅B and iNOS showed higher positive reaction in the ADE, PEAT and CRA than in the Ctrl, but the increase in the positive reaction was lower in the CEA compared to the ADE and PEAT. Substance P and serotonin showed higher positive reaction in the ADE, PEAT and CRA than in the Ctrl, but the increase in the positive reaction was lower in the CEA compared to the ADE and PEAT. Conclusions: The effects of Coptis chinensis extract -ceramide complex were confirmed on the regulation of the ECS, macrophage activity and mast cell activity.

Potential Energy Surfaces for the Reaction Al + O2→ AlO + O

  • Ledentu, Vincent;Rahmouni, Ali;Jeung, Gwang-Hi;Lee, Yoon-Sup
    • Bulletin of the Korean Chemical Society
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    • 제25권11호
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    • pp.1645-1647
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    • 2004
  • Potential energy surfaces for the reaction Al + $O_2{\to}$AlO + O have been calculated with the multireference configuration interaction (MRCI) method using molecular orbitals derived from the complete active space selfconsistent field (CASSCF) calculations. The end-on geometry is the most favourable for the reaction to take place. The small reaction barrier in the present calculation (0.11 eV) is probably an artefact related to the ionicneutral avoided crossing. The charge analysis implies that the title oxidation reaction occurs through a harpooning mechanism. Along the potential energy surface of the reaction, there are two stable intermediates of $AlO_2(C_{{\infty}v}$ and $C_{2v}$) at least 2.74 eV below the energy of reactants. The calculated enthalpy of the reaction (-0.07 eV) is in excellent agreement with the experimental value (-0.155 eV) in part due to the fortuitous cancellation of errors in AlO and $O_2$ calculations.

Initial Reaction of Hexachlorodisilane on Amorphous Silica Surface for Atomic Layer Deposition Using Density Functional Theory

  • Kim, Ki-Young;Yang, Jin-Hoon;Shin, Dong-Gung;Kim, Yeong-Cheol
    • Journal of the Korean Ceramic Society
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    • 제54권5호
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    • pp.443-447
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    • 2017
  • The initial reaction of hexachlorodisilane ($Si_2Cl_6$, HCDS) on amorphous silica ($SiO_2$) surface for atomic layer deposition was investigated using density functional theory. Two representative reaction sites on the amorphous $SiO_2$ surface for HCDS reaction, a surface hydroxyl and a two-membered ring, were considered. The reaction energy barrier for HCDS on both sites was higher than its adsorption energy, indicating that it would desorb from the surface rather than react with the surface. At high temperature range, some HCDSs can have kinetic energy high enough to overcome the reaction energy barrier. The HCDS reaction on top of the reacted HCDS was investigated to confirm its self-limiting characteristics.

A Study on the Improvement of Decomposition Efficiency of Organic Substances Using Plasma Process and Catalytic Surface Chemical Reaction (플라즈마 프로세스 및 촉매 표면화학반응에 의한 유기화합물 분해효율 향상에 대한 연구)

  • Han, Sang-Bo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • 제59권5호
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    • pp.932-938
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    • 2010
  • This paper proposed the effective treatment method for organic substances using the barrier discharge plasma process and catalytic chemical reaction followed from ozone decomposition. The decomposition by the plasma process of organic substances such as trichloroethylene, methyl alcohol, acetone, and dichloromethane carried out, and ozone is generated effectively at the same time. By passing through catalysts, ozone easily decomposed and further decomposed organic substances. And, 2-dimensional distribution of ozone using the optical measurement method is performed to identify the catalytic surface chemical reaction. In addition, CO is easily oxidized into $CO_2$ by this chemical reaction, which might be induced oxygen atom radicals formed at the surface of catalyst from ozone decomposition.

Pt/Al Reaction Mechanism in the FeRAM Device Integration (FeRAM 소자 제작 중에 발생하는 Pt/Al 반응 기구)

  • Cho Kyoung-Won;Hong Tae-Whan;Kweon Soon-Yong;Choi Si-Kyong
    • Korean Journal of Materials Research
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    • 제14권10호
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    • pp.688-695
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    • 2004
  • The capacitor contact barrier(CCB) layers have been introduced in the FeRAM integration to prevent the Pt/Al reaction during the back-end processes. Therefore, the interdiffusion and intermetallic formation in $Pt(1500{\AA})/Al(3000{\AA})$ film stacks were investigated over the annealing temperature range of $100\sim500^{\circ}C$. The interdiffusion in Pt/Al interface started at $300^{\circ}C$ and the stack was completlely intermixed after annealing over $400^{\circ}C$ in nitrogen ambient for 1 hour. Both XRD and SBM analyses revealed that the Pt/Al interdiffusion formed a single phase of $RtAl_2$ intermetallic compound. On the other hand, in the presence of TiN($1000{\AA}$) barrier layer at the Pt/Al interface, the intermetallic formation was completely suppressed even after the annealing at $500^{\circ}C$. These were in good agreement with the predicted effect of the TiN diffusion barrier layer. But the conventional TiN CCB layer could not perfectly block the Pt/Al reaction during the back-end processes of the FeRAM integration with the maximum annealing temperature of $420^{\circ}C$. The difference in the TiN barrier properties could be explained by the voids generated on the Pt electrode surface during the integration. The voids were acted as the starting point of the Pt/Al reaction in real FeRAM structure.

Effect of Skin Lipid Barrier Formation on Hataedock Treatment with Douchi

  • Kim, Hee-Yeon;Ahn, Sang-hyun;Yang, Injun;Kim, Kibong
    • The Journal of Korean Medicine
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    • 제38권2호
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    • pp.41-52
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    • 2017
  • Objectives: Hataedock is indigenous treatment of Korean medicine that administers herbal extracts orally to newborn infants for remove the fetal heat. The purpose of this study was to evaluate skin lipid barrier formation effect of Hataedock treatment with Douchi. Methods: We measured the Western blot to observe the expression of protein such as involucrin and loricrin. Moreover, we observed immunohistochemical changes in NC/Nga mice. The 3-week-old NC/Nga mice were divided into 3 groups: the 3-week-old control group (3w-Ctrl), 5-week-old control group (5w-Ctrl), and the Hataedock-treated group (5w-FGT). Only the 5w-FGT group was treated with Douchi at the 3rd week. We identified the changes of the lipid skin barrier and protein differentiation through immunohistochemical changes of involucrin, loricrin, filaggrin and acid sphingomyelinase (ASM) in the stratum corneum. Results: The expression of involucrin and loricrin was increased in the Western blot that was treated with concentration of Douchi extracts. In 5w-FGT group, loricrin-positive reaction was increased by 54.0%, involucrin-positive reaction was increased by 84.0%, filaggrin-positive reaction was increased by 108.0% and ASM-positive reaction was increased by 91.0% in the stratum corneum. Conclusions: These results suggest that Hataedock treatment with Douchi promoted skin lipid barrier formation by promoting differentiation of keratinocytes.

Facilitation of the four-mask process by the double-layered Ti/Si barrier metal for oxide semiconductor TFTs

  • Hino, Aya;Maeda, Takeaki;Morita, Shinya;Kugimiya, Toshihiro
    • Journal of Information Display
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    • 제13권2호
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    • pp.61-66
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    • 2012
  • The double-layered Ti/Si barrier metal is demonstrated for the source/drain Cu interconnections in oxide semiconductor thin-film transistors (TFTs). The transmission electromicroscopy and ion mass spectroscopy analyses revealed that the double-layered barrier structure suppresses the interfacial reaction and the interdiffusion at the interface after thermal annealing at $350^{\circ}C$. The underlying Si layer was found to be very useful for the etch stopper during wet etching for the Cu/Ti layers. The oxide TFTs with a double-layered Ti/Si barrier metal possess excellent TFT characteristics. It is concluded that the present barrier structure facilitates the back-channel-etch-type TFT process in the mass production line, where the four- or five-mask process is used.