The pot patch should be flat during use, but there will also be such a situation: it is flat when it is just attached to the PCB board, but after a while, the edge of the pot patch will warp, resulting in dust entering and poor contact. So what is the cause of this problem? Let's analyze it briefly.
The pot patch is a double-layer structure, the thickness of the upper layer is generally 0.05MM, the thickness of the lower partition layer is generally 0.075MM, the pot piece is located in the lower partition layer, if the height is relatively high triangle or cross-shaped pot piece (height 0.4-0.7MM), the height difference between the pot piece and the partition layer is large, once the pot piece is close to the edge, it will cause the pot piece patch to warp. To solve this problem, we can start with two aspects. First, during the design process, don't get too close to the edges and leave enough space to prevent warping. Secondly, we can thicken and glue the partition layer to prevent the pan patch from warping.
