S-pad implementation; total plastic package crack solution for non-moisture sensitive package

This paper investigates capability of following technologies; mold compound, die attach adhesive, textured die pad, and buffer coat, in resolving or improving the package crack performance of plastic package during reflow soldering process. We have finally succeeded in resolving this problem by making a die pad smaller than chip size and analyzed the stress, thermal and electrical characterization by using the simulation to determine suitable scoop size and lead frame line-up. The chip size limitation was confirmed by actual experiments for a chip size, a package size and a package thickness.