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PCB Pre-Manufacturing Checklist Form

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Your Design Package Needs to be Complete to Avoid Delays and Other Hassles

Specify Processing Instructions:

Some needed information isn't included in your Gerber (or even CAD) files. So, the package provided to the manufacturer should include a file (PcbPackage.xml or ReadMe.txt) that specifies:

Finished board thickness
Color of Solder mask to be used
Color of the printing (aka. silk or nomenclature)
Copper thickness for outer layers (often specified in ounces per squire foot)
Copper thickness for inner layers
Which core material to use
If the addition of theiving (extra copper to improve overall plating) by the manufacturer is allowed or not

Provide the Needed Gerber or CAD Files:

Some manufacturing steps require "pictures" of the material (copper, ink or solder mask) as it should appear in the final product. The imagery can be supplied as Gerber files, which is the mechanism supported by the broadest range of manufactureers, or by providing native CAD files.

If providing files in Gerber 274-D format, one or more aperture definition files
Board Outline (particularly if your board is non-rectangular)
Top/Component Side Nominclature
Top/Component Side Solder Mask
Top/Component Side Copper
All Inner Layer Copper
Bottom/Solder Side Copper
Bottom/Solder Side Solder Mask
Bottom/Solder Side Nominclature

Provide Excellon Drill File(s):

Drilling holes is a mechanical operation that requires information not traditionally specified in Gerber files. The most common format for specifying hole locations and sizes is "Excellon format."

Hole sizes are specified per the manufacturers requirements and so called-out in the ReadMe.txt or PcbPackage.xml file
Smallest and Largest hole sizes are within manufacturer's capabilities
All hole sizes match manufacturer's capabilities where fixed drill sizes are specified
Plated and non-plated holes are sepatarated by file
Route-paths for (if provided) are specified in a separate file

Design for Manufacturability:

Following some simple rules in your design can help lower your costs and your manufacturers yeild. Here are a few basic ones:

Use traces as wide as is reasonable. Shoot for 8 mil (0.008") traces for economical manufacturing.
Maintain 10 mil (0.010") spaces between traces and other features
Keep "webs" of solder mask between pads to at least 4 mil (0.004") thickness
Avoid making copper shapes that are concave (watch joints between traces and rectangular pads)
Keep all features at least 30 mils from the edge of the board (except pads for edge connections)
Avoid drawing silkscreen on pads. Pre-clipping your silkscreen layers to the soldermask layer helps avoid delays and prevents issues with testing and assembly of the board.
Try to avoid placing "extra" information into the gerbers such as titleblocks or instructions. Put instructions in the readme, where they belong.

This is just a partial list of things to consider. If you have suggestions for generally appropriate items that should go on this list, please send us an email and we'll consider adding them.