1. The space between large area grids is too small, and the edge between large area grid lines is too small (less than 0.3mm). In the process of PCB manufacturing, many broken films are easy to be produced in the drawing conversion process after the development and adhesion on the board, resulting in wire breakage.
2. The distance between the large area copper foil and the outer frame is too close. The distance between the large area copper foil and the outer frame should be at least 0.2mm. If the copper foil is milled to the outer frame, it is easy to cause the copper foil warping and the solder resist falling off.
3. The design of the outline is not clear. Some customers have designed the outline lines in the keep layer, board layer, top over layer, etc., and these outline lines do not coincide, which makes it difficult for PCB manufacturers to judge which outline line should be taken as the standard.
4. Uneven pattern design results in uneven coating and affects the quality of pattern electroplating.
5. The length / width of the special-shaped hole should be greater than or equal to 2:1, and the width should be less than or equal to 1.0 mm. Otherwise, the drilling machine is easy to break the drill when processing the special-shaped hole, resulting in processing difficulties and increasing costs.