[case description and cause analysis]

This kind of slot is not output when the layer is output. The board factory did not carefully review the production, ignored this kind of slot, and made directly according to the round hole of the drilling layer. As a result, customers can not use the plug-in, resulting in the whole batch of boards scrapped and redone.

【祥达丰的做法，分三步走】

第一步：封装制作时，取消在槽孔位置处理做圆孔标识。

Step 2: output the. Rou layer separately in the software to facilitate comparison.

Step 3: mark the size in the drill layer aperture table, and mark slot number in the notes list.