Issue link: https://iconnect007.uberflip.com/i/989774
JUNE 2018 I SMT007 MAGAZINE 81 line with T4 paste into compliance with the benchmark for ARs of 0.69 and 0.62, but again, showed very little difference in TE and CV between the standard and high-tension mountings. Finally, going for the absolute worst-case scenario possible—circular, copper-defined pads, with T4 paste after a 90-minute pause— all the trends remained constant. As seen in Figure 17, the paste release was extremely simi- lar to that of Time 0, with the higher tension stencil showing a very slight potential advan- tage in TE, and little effect on CV. Comparing the effects of nanocoating to the effects of high tension, these tests indicate that nanocoating offers far greater benefit than Figure 16: Comparison of effect of foil mounting tension on print quality with Type 5 solder paste and worst-case scenario pad design. Figure 15: Comparison of effect of foil mounting tension on print quality with Type 4 solder paste and worst-case scenario pad design.