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JANUARY 2024 I SMT007 MAGAZINE 49 process capability of ± 56.4 μm at 3-sigma and in the Y axis of ± 46.5 μm at 3-sigma. e XY positioning of this dot is considerably more inaccurate compared with the dot of Zone A because to be able to jet the uneven area of the center of the TQFP (Zone B), the jetting dis- tance must be substantially higher. Higher jet- ting distances tend to give less accurate posi- tioning results. e process capability report for the dot diameter is shown in Figure 9. e average dot diameter is 674.7 μm and its pro- cess variability is ± 8.1% at 3-sigma. Figure 10 illustrates the complete TQFP aer jetting. A second jetting process to replace a BGA with 200 μm pad diameter with 400 μm pitch was analyzed. is component required a low temperature type 6 paste with an Sn63Bi37 alloy. For this product, a needle length of 1 mm with an opening of 0.15 mm was selected. e same procedure as in the previous product was average dot diameter is 262.7 μm and its pro- cess variability is ± 17.5% at 3-sigma. Figure 6 illustrates the 200 μm pads aer jetting. e same procedure was used to verify the capability of the process applied for Zones B and C. In these zones, the use of a nozzle is pos- sible because there are no components close to the jetting areas. Figure 7 and Figure 8 show the process capability report for X and Y posi- tioning. e positioning in the X axis gives a Figure 6: 400 μm pitch after jetting. Figure 10: Complete TQFP after jetting. Figure 7: Distribution of the X positioning in zones B and C. Figure 8: Distribution of the Y positioning in zones B and C. Figure 9: Dot diameter distribution in zones B and C.