Prepare solder mask-defined pads for manufacturing

SMD and NSMD describe the exposed pad

For a solder mask-defined pad, the mask opening is smaller than the copper pad and overlaps its perimeter. For a non-solder mask-defined pad, the mask opening extends beyond the copper edge. Here, SMD describes pad geometry; it is not the same abbreviation as a surface-mount component.

Set the geometry in the source design

1. Start with the component manufacturer’s land-pattern recommendation and the intended assembly process.
2. Set the copper pad and solder-mask opening in the PCB footprint or relevant rules. Do not use a generic expansion value for every fine-pitch package.
3. Check mask registration, minimum mask web and clearances against the DIYIPCB capability information, and confirm marginal features before release.

Check the exported mask layer

Overlay copper and solder-mask Gerbers in a viewer and measure the opening. Confirm that local footprint settings were not overridden by a board rule or export setting. Check both sides where applicable. Paste apertures control stencil printing and must be reviewed separately from solder mask.

Explain intentional mask overlap

Identify affected reference designators or pad groups in the fabrication notes and state that the overlap is intentional. Provide a dimensioned detail if necessary. Ask for review when the design approaches process limits; do not rely on the archive name to communicate pad intent.

Upload to DIYIPCB

Open DIYIPCB PCB / PCBA Online Quote, upload the Gerber ZIP and choose the material, specifications and quantity. Verify the displayed dimensions and layer count against your design; the preview is a reference, not engineering approval.

For bare PCBs, the Gerber ZIP must also contain the drill data. For assembly, provide a matching BOM and placement file as well. Use the available cart or inquiry option for your selected service. See BOM and placement-file requirements.