半導体封止用エポキシ樹脂の流動特性
Flow Characteristics of Epoxy Compounds for Encapsulation of Semiconductor Devices
佐伯準一
Saeki, Junichi
The flow characteristics of silica-filled epoxy compounds used for encapsulation of semiconductor devices were examined. For measuring shear viscosity in the absence of rapid chemical reactions that can cause drastic viscosity rises, trial compounds without hardening accelerators were used. A plunger extrusion type of rheometer was designed for this study. By changing the combination of plunger velocity and the dimensions of the circular channel, shear rates ranging from 1 to 104s-1 were obtained. The channel length correction of Bagley's method was found to be negligibly small. The molten compounds showed shear thinning behavior over the tested ranges of temperatures and shear rates. Notably, strong shear thinning behavior was observed at very low shear rates. Within the shear rate range from approximately 1 to 20s-1 values for the power law index ranged from around 0.3 to 0.4. The relationship between temperature and pseudoplastic viscosity k was found to be expressed by an Andrade's equation.
Key words: Epoxy compounds / Viscosity / Shear rate / Power law fluid