abstract |
The mechanisms for forming bumps on packaged dies and package substrates reduce variation of bump heights across the packaged dies and packaged substrates. Bumps are designed to have different widths to counter the higher plating current near edge(s) of dies or substrates. Bump sizes can be divided into different zones depending on the bump patterns and densities across the packaged die and/or substrates. Smaller bumps near edges reduce the thickness of plated film(s), which would have been thicker due to being near the edges. As a result, the bump heights across the packaged dies and/or substrates can be kept significantly constant and chip package can be properly formed. |