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oe1(光电查) - 科学论文

3 条数据
?? 中文(中国)
  • Effect of plasma treatment on adhesion strength and moisture absorption characteristics between epoxy molding compound/silicon chip (EMC/chip) interface

    摘要: Reliability of interface between two dissimilar materials becomes an important issue due to increasing demands of high-density integrated circuits. Most of failures of semiconductor package occur at the interface between two dissimilar materials in high temperature reflow process, thus, adhesion strength under high temperature should be investigated. In this study, an adhesion shear test jig was newly devised to measure the adhesion strength of epoxy molding compound/Si chip (EMC/chip) interface at high temperature (200 °C). In order to investigate the effect of plasma treatment on adhesion strength and moisture absorption characteristics, the number of plasma treatments was varied. Also, moisture absorption time was varied to observe the moisture uptake and degradation of adhesion strength with respect to plasma treatment number. Atomic force microscope (AFM) was analyzed to verify the surface roughness of silicon chip, and scanning electron microscopy (SEM) was used to observe cross-sectional fractured morphology after adhesion strength test. From this study, it was found that the plasma treatments affect much the adhesion strength and moisture uptake at the interface between the EMC/Chip interface.

    关键词: Semiconductor package,Moisture absorption,Adhesion strength,Plasma treatment

    更新于2025-09-23 15:23:52

  • [IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Compact Single-Shot D-Scan Setup for the Characterization of Few-Cycle Laser Pulses

    摘要: The power generator is typically maintained with a time- or usage-based strategy, which could result in a substantial waste of remaining useful life, high maintenance cost, and low plant availability. Recently, the field of prognostics and health management offers diagnostic and prognostic techniques to precisely assess the health condition and robustly predict the remaining useful life (RUL) of an engineered system, with an aim to address the aforementioned deficiencies. This paper explores a smart health reasoning system to assess the health condition of power generator stator bars against moisture absorption based on the statistical analysis of the capacitance measurements on bar insulators. In particular, a relative health measure, namely the directional Mahalanobis distance, is proposed to quantify the health condition of a stator bar. The smart health reasoning system is validated using five years’ field data from seven generators, each of which contains 42 turns.

    关键词: health diagnostics,statistical correlation,moisture absorption,Directional Mahalanobis distance (DMD),power generator stator bar

    更新于2025-09-19 17:13:59

  • Moisture absorption and hydrothermal aging of phenylethynyl-terminated pyromellitic dianhydride-type asymmetric polyimide and composites

    摘要: The effects of moisture on a polymerized monomeric reactant (PMR)-type polyimide (TriA X) and associated composites were investigated. Water uptake tests were performed on the polyimide at various temperatures and relative humidity levels to investigate moisture absorption behavior. Two-stage moisture absorption was observed, in which the first stage was diffusion controlled, whereas the second stage was moisture plasticization controlled. As exposure temperature increased, the equilibrium moisture content of the polyimide decreased, indicating an exothermic absorption process. The Arrhenius temperature dependence and moisture saturation as functions of temperature and humidity in the neat polymer were determined using curve fitting based on the published mathematical models. Long-term hydrothermal aging at 95°C was conducted on the neat polyimide and associated carbon fiber composites. Reversible hydrolytic reactions and a trace of irreversible hydrolysis were observed in the long-term exposure. The tensile ductility of the neat polyimide and the short-beam shear strength of the composites decreased with increasing aging time, while the tensile strength and modulus and thermal properties of the polyimide exhibited little change after 2000-h aging, demonstrating hydrothermal stability. The decrease in the ductility of the neat polymer after long-term moisture exposure was attributed to the network structure change, driven by hydrolysis and moisture plasticization.

    关键词: β-relaxation,hydrothermal aging,moisture absorption,thermal properties,hydrolysis,Polyimide,composite,mechanical properties,plasticization

    更新于2025-09-04 15:30:14