Optimizing Solder Paste Printing For Wafer Bumping

摘要

Recently, wafer bumping using solder paste with very fine solder powder has come into focus as more cost effective thanrnconventional sputtered or plated methods. This additive method revolves around a stencil printing process similar tornconventional SMT with the exception of the extremely small pitch and desired deposit size. The results and findings of arnprint process array of experiments are presented that focus on optimal print deposit area consistency. Variables such asrnsqueegee type (polymer vs. metal), separation speed and snapoff distance are compared and contrasted.