1. Paste coverage for fine pitch components like 0201 's and small apertures (140 microns) is significantly better for the AMTX E-FAB stencil compared to the Laser-Cut stencil for Lead Free Solder pastes. This was also the case for Lead solder paste as shown in prior publications.'1'2' 2. Paste smearing was lower for the AMTX E-FAB stencil using the electroformed E-Blade compared to the Laser-Cut stencil using the OEM blade, in both cases Paste A was used. 3. The best Spread Test results (minimum bridging between solder bricks) was achieved for the AMTX E-FAB stencil / Paste A / E-Blade combination. 4. The best Aperture Test results (bridging / opens) was achieved for the AMTX E-FAB stencil / Paste B / E-Blade combination. 5. The best Paste Transfer results was achieved for the AMTX E-FAB stencil / Paste B / E-Blade combination. 6. The E-Blade demonstrated the lowest squeegee pressure for all combinations except for Laser-Cut / Paste C. 7. Paste B with the E-Blade demonstrated the lowest squeegee pressure at. 14 Kgms/cm. 8. When comparing the five different squeegee blade types the E-Blade provided the lowest squeegee pressure of any in the group. 9. When comparing the residue paste left on the squeegee blade after printing it was found there is very little variation from blade to blade. The variation was 10 grams up to 17 grams. Even at 17 grams there was not nearly enough paste to get on the blade holder where it could be a problem.
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