3d-numerical Model Of BPSG Reflow Using Surface Diffusion
M. Fujinaga, I. Tottori, T. Kunikiuyo · 2005
This paper presents a three-dimensional (3D-) numerical surface diffusion model of BPSG glass reflow of surface tension. The BPSG surface is described as an equiconcentration area. 3D-surface curvature is defined consistently as the ratio of the increment of surface area to that of volume in a small interface area. The flux of reflow is proportional to the gradient of the surface curvature and the direction is from the area of small curvature to that of large curvature. The algorithm is that an analysis region is divided into small cells, and the surface particles move from the mass-center of the equi-concentration area of a cell to that of the neighbor cells across the contact lines of the cell boundary and the equi-concentration area. This model is implemented using 3D-MULSS topography simulator and the simulation of reflow is possible for general 3D-topography. A 3D-simulation of reflow using 3D-MULSS is shown and compared with an experiment.