Recent Advances of Flip-Chip Underfill Process(2)

In order to enhance the reliability of a flip chip on organic board package,underfill is usually used to redistribute the thermo mechanical stress created by the coefficient of thermal expansion(CTE) mis-match between the silicon chip and organic substrate. However,the conventional underfill relies on the capillary flow of the underfill resin and has many disadvantages. In order to overcome these disadvantages,many variations have invented to improve the flip chip underfill process.