DFM Analysis

Solder Paste Analysis will primarily include:

 

  • Solderpaste Not on SMD 

Solderpaste on non-SMD pads may result in shorts.

  • SMD Pad Without Solderpaste

Missing solderpaste may result in broken net connectivity


  • Testpoint Without Solderpaste 

Some production processes, such as OSP, require that testpoints have solderpaste applied to make sure that the test probes have good contact.

  • THMT Without Solderpaste 

Some production processes, such as lead-free processes, require solderpaste applied to THMT pads/drills to enhance good soldering.

  • Solderpaste Not Exposed by Solder Mask

Solderpaste which does not contact pads, due to solder mask, may result in broken net connectivity.

  • Solderpaste Outside Copper 

Solderpaste not on pads may result in shorts.

  • SP to SM 

If solderpaste pads are too close to solder mask clearances, manufacturing imprecisions, such as a shift in the solderpaste stencil or the solder mask layer, could cause solder bridging between solderpaste and the copper inside the solder mask clearance.

  • SP to SP 

Solderpaste pads too close together can cause a short, or indicate a design problem.

  • SP to Rout 

Purpose: To detect cases of soldepaste applied too close to the rout.


  • SP to PTH 

Purpose: To detect cases of soldepaste applied too close to a PTH drill.

  • SP to NPTH

Purpose: To detect cases of soldepaste applied too close to an NPTH drill.

  • Roof Area / Wall Area (Feature) 

If side wall area is too large in comparison to roof area, the solderpaste might stick to the stencil when removing it from the PCB.

  • Roof Area / Wall Area (Side) 

If side wall area is too large in comparison to roof area, the solderpaste might stick to the stencil when removing it from the PCB.

  • Hole Inside SP Feature 

A clearance within a metal mask could lead to an inadequate amount of solderpaste being applied on the board.