Here is the abstract you requested from the IMAPS_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Development of Newly Instrumented Plastometer and Rheological Characterization of the Low Shear Zone of an Epoxy Molding Compound for Encapsulation of Semiconductor Devices|
|Keywords: Epoxy Molding Compound for Encapsulation, Rheological Characterization, Moldability Evaluation|
|In encapsulation molding of IC packages, the melt flow inside the cavity is generally in a low shear zone to prevent wire sweep, bump flow, and other molding defects. Therefore, it is important to evaluate the rheological properties of epoxy molding compounds (EMC) in a low shear zone including determining the yield stress. In this study, a new instrument - a precision Parallel-Plate Plastometer - was developed in order to evaluate the yield and rheological properties of EMCs. Since the plastometer is equipped with a high-speed laser-displacement meter, it enables the evaluation of low-viscosity melt flow such as in the case of EMCs. Using this plastometer, the yield stress and its temperature dependence were clarified, and the rheological properties in the low shear zone were evaluated. As a result, the rheological properties in a low shear zone of 0.1-10 s-1 were characterized using the Herschel-Bulkley viscosity model which introduced the yield stress, the Castro-Macosko equation as a dependency model of cure, and the WLF equation as a dependency model for temperature. Furthermore, it was clarified the correlation between the rheological properties in low shear and flow behavior, molding defects (wire sweeps, weld voids).|
|Masaki Yoshii, Chief Researcher
Hitachi Chemical Co., Ltd.
Yuki-city, Ibaraki 307-0015,