| Summary: | 碩士 === 國立雲林科技大學 === 機械工程系碩士班 === 93 === The mold flow software C-MOLD and Moldflow are used to simulate the flow behavior of Fine-Pitch Ball Grid Array （FBGA） package during encapsulation. The molding behavior during encapsulation for different chip thicknesses and offsets of hole on the substrate are discussed. The wave front shape predicted by simulation is compared with the shape by short shot experiment to verify the accuracy of the simulation model. The wire sweep during the encapsulation is predicted by C-MOLD, Moldflow, as well FEM software ANSYS, where the applied load is the drag force calculated by the acquisition of the flow viscosity and velocity from the mold flow simulation. The predictions of the wire sweep are compared with the experimental measurements. Also, the effects of chip thicknesses and offsets of hole on the substrate on the wave front difference between mold halves, wire sweep, and resin bleed are discussed.
For the thermal analysis, the ANSYS software is used to build the FEM solid model and CFD fluid-thermal model of Micro Ball Grid Array Package （μBGA） to predict the thermal resistance of the package under the natural and forced convection, and the predicted thermal resistance is compared with the experimental measurement to verify the accuracy of the simulation. The averaged surface convection coefficients for both package and PCB （Printed Circuit Board） surfaces acquired from the CFD model are compared with the plate surface convection coefficients to show the difference. Furthermore, the effects of chip thickness, flow velocity, and PCB thickness on the thermal performance of the package are discussed.
|
|---|
