BGA tin-lead solder ball solidification process simulation method based on cellular automaton

Abstract

The invention discloses a BGA tin-lead solder ball solidification process simulation method based on a cellular automaton, and belongs to the field of metal solidification process simulation. In orderto solve the problem that when a cellular automaton method is used for simulating a metal solidification process at present, the situation that under the condition of non-isothermal and non-equal solute interfaces, an unbalanced interface series model needs to be used for simulating the rapid solidification process of a supercooled alloy melt is not considered, so that the simulation process doesnot meet the actual solidification process of a BGA tin-lead solder ball. The method includes: acquiring physical property parameters; uniformly dividing a fixed two-dimensional calculation area intosquare grids; initializing a unit cell; establishing a dendritic crystal growth model; capturing the liquid phase cells; calculating the solid-phase growth rate of the captured adjacent interface cells, the concentration of residual liquid-phase solute and the temperature of unit cells according to the established dendritic crystal growth model; accumulating the unit time step length obtained byeach time of calculation, and ending the calculation simulation process. The method is used for researching the growth process of the isometric crystal and the influence of different supercooling degrees on the growth of the isometric crystal.

Description

technical field [0001] The invention belongs to the field of metal solidification process simulation, and in particular relates to a method for simulating the solidification process of BGA tin-lead solder balls. Background technique [0002] Numerical simulation builds a bridge between theoretical and experimental research and greatly promotes scientific and technological progress. Cellular automata simulation, as a general simulation method, has attracted more and more attention. At the same time, as the feature size of integrated circuits shrinks, the importance of ball grid array packaging (BGA) becomes increasingly prominent. The comprehensive performance of tin-lead precision solder balls is crucial to the reliability of BGA micro-interconnection. The invention simulates the solidification process of micron-level tin-lead precision solder balls used for BGA based on cellular automata simulation. [0003] The containerless solidification (containerless solidification)...

AI Technical Summary

Problems solved by technology

This makes theoretical research and mathematical analysis encounter great difficulties

Moreover, since the solidified liquid metal is often at a relatively high temperature, and the metal itself is opaque and in a fluid state, this makes experimental research lack direct and effective methods.

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