Stencil is damaged which will result in Excess paste on the BGA pads resulting in Bridging after Reflow
Stencil Aperture Blocked after Laser Cutting which will result in no paste on to the pads.
Bridging or Shorts on two pads which can result in soder short after reflow
Solder Slump which is very rare mainly occurs due to Temperature.
Scooping which is mainly caused due to High Squeegee Pressure resulting in less solder.
Bleeding is caused because of the Board Vacuum on the printer which results in solder balls
Residues is because of improper cleaning of the board resulting in solder balls.
Incomplete print is due to improper cleaning of the stencil.
Slamp is because of the contact with the stencil, the stencil has either flexed during separation with the board or the board has lifted
Paste Misalignment is result of poor alignment which will result in solder shorts
No comments:
Post a Comment