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In Cu wire technology, it is observed that the Cu–Al IMC formation increases from a very thin layer of a few nm to a few μm after subjected to annealing process. The identified IMC phases are mainly CuAl 2 , CuAl and Cu 9 Al 4 , whereas the other three phases which are less reported are Cu 4 Al 3 , Cu 3 Al 2 and Cu 3 Al. The reliability risk of Cu–Al IMC is commonly known, with the degradation of voids or crack propagation from ball periphery to internal ball bond direction after long duration of annealing. However, the cause of the degradation is not well established. This paper will focus on the study of the degradation of Cu–Al IMC layers with and without the presence of a mold compound by using ex-situ post annealing and in-situ annealing method on the same assembled sample. The ex-situ post annealing sample is studied using focus ion beam (FIB) after the molded sample had underwent a standard High Temperature Storage (HTS) at 150 °C for 1000 h. The in-situ annealing sample is studied using a transmission electron microscope (TEM) on a lamella with Cu–Al interface but without the presence of a mold compound. The result shows that the IMC formed are identified as CuAl 2 , CuAl and Cu 9 Al 4 via Energy Dispersive Spectrometer (EDX). These IMC are seen to grow increasingly with the duration of annealing process for both methods. The native Al oxide lines are seen for both methods and were embedded in between the IMC. The degradation starts at the ball periphery with cracks and voids at IMC are seen for the ex-situ postannealing sample but it is not observed under in-situ annealing sample. It is found that the degradation of the IMC is not caused by propagation of microcrack; instead it is assumed to be the influence of additive within the mold compound itself. [ABSTRACT FROM AUTHOR]

Kapton tape is often used for co-planarity of inner metal lead frame parts in the packaging of semiconductor components. It is made of organic material known as high temperature insulating tape. In this paper, the increment of leakage current in a packaged component that is caused by a Kapton tape was studied. The leakage measurement on Kapton tape was done using simple testing instruments such as source meter, micro prober and temperature controlled hot plate. The different leakage current characteristics were investigated on high temperature, test duration and length of the Kapton tape. According to the measured leakage current on various dependencies, it is suggested the leakage is due to mobile ion in Kapton tape. Various analysis techniques were able to identify the mobile ion was Sodium ions in the glue of the Kapton tape. Based on the observation, a model explaining the Sodium mobile ions failure mechanism in the Kapton tape was established. The deployment of leakage test can be applied to test incoming lead frame material. The test set up did not require expensive tester equipment and manufactured devices. It could also be transferred as new outgoing quality check mainly for lead frame suppliers. [ABSTRACT FROM AUTHOR]

Abstract: The growth of graphene on Ni using a photo-thermal chemical vapor deposition (PT-CVD) technique is reported. The non-thermal equilibrium nature of PT-CVD process resulted in a much shorter duration in both heating up and cooling down stages, thus allowing for a reduction in the overall growth time. Despite the reduced time for synthesis compared to standard thermal chemical vapor deposition (T-CVD), there was no decrease in the quality of the graphene film produced. Furthermore, the graphene formation under PT-CVD is much less sensitive to cooling rate than that observed for T-CVD process. Growth on Ni also allows for the alleviation of hydrogen blister damage that is commonly encountered during growth on Cu substrates and a lower processing temperature. To characterize the film’s electrical and optical properties, we further report the use of pristine PT-CVD grown graphene as the transparent electrode material in an organic photovoltaic device (OPV) with poly(3-hexyl)thiophene (P3HT)/phenyl-C61-butyric acid methyl ester (PCBM) as the active layer where the power conversion efficiency of the OPV cell is found to be comparable to that reported using pristine graphene prepared by conventional CVD. [Copyright &y& Elsevier]

Abstract: An enhancement by 5 orders of magnitude of the electrical conductivity of nanoclustered carbon films is reported by incorporation of metallic atoms, but without significant morphological changes. Films were deposited by 248nm pulsed laser ablation of both a pyrolytic graphite target and a mixed carbon–nickel (C:Ni) target, and structural analysis revealed that similar film morphologies were obtained when deposition was carried out using either target. Compositional analysis demonstrated a preferential incorporation of nickel over carbon in the resulting films (cf. the composition of the target). This non-stoichiometric transfer was also observed for films grown by 193nm laser ablation of the C:Ni target, for which the enhancement was more pronounced, indicating that the ablation mechanism and the subsequent transfer are important in determining the eventual film composition. [Copyright &y& Elsevier]

Abstract: The water resource system, related to society, economy and environment, is a compound feedback system. Supply and demand of the water resources in basins interacts with the development of social economy as well as the aquatic ecosystem. Therefore once suffering crisis of water shortage, not only the socioeconomic system will be confronted with large financial loss, but also the original aquatic ecological equilibrium in basins will be broken. This paper constructed an early warning system of water shortage by using Stella software based on the system dynamics (SD) model, which has been believed to delineate clearly the coupling correlation between the water resource and the social economic system and aquatic ecosystem. The ecological flow was considered as an indispensable element in the water demand. So the calculation model of ecological flow was involved in the SD model, which distinguished it from traditional model of water resources supply and demand. Moreover, the supply and demand ratio was chosen to predict the variation of supply and demand of the socioeconomic water as well as ecological flow by means of simulation under a given scenario of water shortage. [ABSTRACT FROM AUTHOR]

Abstract: Octopus-like carbon nanofibres with leg diameters as small as 9nm are reported, with a high yield over large areas, using a unique photo-thermal chemical vapour deposition system. The branched nature of these nanostructures leads to geometries ideal for increasing the surface area of contacts for many electronic and electrochemical devices. The manufacture of these structures involves a combination of a polyacrylonitrile/polysiloxane film covering the surface of cupronickel catalysts, supported on silicon. Acetylene is used as the carbon feedstock. High-resolution electron microscopy revealed a relationship between the geometry of the nanoparticles and the catalytic growth process, which can be tuned to maximise geometries (and therefore the surface area) and was obtained with a catalyst size of 125nm. The technique proposed for growing these carbon octopi nanostructures is ideal to facilitate a new in situ transfer film process to place high-density carbon structures on secondary surfaces to produce high capacitance all-carbon contacts. [Copyright &y& Elsevier]