PRINTING CAPABILITY STUDY OF 008004 (0201 m) COMPONENTS FOR SiP APPLICATIONS - Part II

摘要

In the previous paper, a printing test had been done on 008004 components. In the study, the attempted apertures were smaller than the usual 008004 pads, so as to simulate paste reduction, to allow very close pad-to-pad distance, and to prevent bridging. The target was to achieve a 50μm gap between component pads without bridging during paste printing. However, the achievable distance was 80μm during previous test setup conditions. In this part of the study, printing setups utilized an electroform stencil and also vacuum tooling to minimize gasketing problems during solder paste printing. We also attempted to print even smaller apertures down to 120μm × 60μm, with an area ratio of 0.57. In order to meet up with the 5 ball rule, T7-SG powders were tested to see how fine we could print with the setup and whether it could achieve 50μm component gap printing. Results show that 50μm gap printing is possible with the correct setup. The support of the PCB while printing is extremely important and could affect the printing consistency significantly.