• Title/Summary/Keyword: acoustic viscosity

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Development of Curing Process for EMC Encapsulation of Ultra-thin Semiconductor Package (초박형 반도체 패키지의 EMC encapsulation을 위한 경화 공정 개발)

  • Park, Seong Yeon;On, Seung Yoon;Kim, Seong Su
    • Composites Research
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    • v.34 no.1
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    • pp.47-50
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    • 2021
  • In this paper, the Curing process for Epoxy Molding Compound (EMC) Package was developed by comparing the performance of the EMC/Cu Bi-layer package manufactured by the conventional Hot Press process system and Carbon Nanotubes (CNT) Heater process system of the surface heating system. The viscosity of EMC was measured by using a rheometer for the curing cycle of the CNT Heater. In the EMC/Cu Bi-layer Package manufactured through the two process methods by mentioned above, the voids inside the EMC was analyzed using an optical microscope. In addition, the interfacial void and warpage of the EMC/Cu Bi-layer Package were analyzed through C-Scanning Acoustic Microscope and 3D-Digital Image Correlation. According to these experimental results, it was confirmed that there was neither void in the EMC interior nor difference in the warpage at room temperature, the zero-warpage temperature and the change in warpage.

Effect of Irradiation Temperature on Physicochemical and Sensory Properties of Tarakjuk (Milk Porridge) (방사선 조사 온도가 타락죽의 이화학적 및 관능적 품질 특성에 미치는 영향)

  • Han, In-Jun;Song, Beom-Seok;Lee, Ju-Woon;Kim, Jae-Hun;Choi, Kap-Sung;Park, Jeong-Ro;Chun, Soon-Sil
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.9
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    • pp.1307-1313
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    • 2011
  • This study was conducted to evaluate the effects of irradiation temperature on the physicochemical and sensory properties of Tarakjuk, milk porridge. Tarakjuk was gamma-irradiated at different temperatures of $25^{\circ}C$ (in room), $4^{\circ}C$ (in ice), and $-20^{\circ}C$ (in dry ice) at a dose of 10 kGy, and then autoclaved at $120^{\circ}C$ for 15 min for comparison. pH and Hunter's color value of Tarakjuk were not changed by irradiation regardless of the temperature. However, the TBA (2-thiobarbituric acid) value decreased as irradiation temperature was decreased. The viscosity of Tarakjuk irradiated in dry ice was significantly higher than that irradiated at room temperature and in ice (p<0.05). For the sensory evaluation, there were no significant differences in overall acceptability between non-treated Tarakjuk and that irradiated in dry ice. Flavor pattern analysis using an electronic nose with a SAW (surface acoustic wave) sensor determined that the main peaks at retention times 3.88 and 7.34 sec were related with off-flavor induced by irradiation and unique flavor of Tarakjuk, respectively. These results indicated that irradiation at freezing temperature improved quality deterioration of Tarakjuk by gamma irradiation. However, sensory quality of Tarakjuk irradiated at freezing temperature was still lower than that of non-irradiated Tarakjuk. Therefore, further research is needed to improve the quality of Tarakjuk using combined treatment such as addition of antioxidants and vacuum packaging method.