1. It is recommended to choose high Tg board for circuit board board selection
For thick copper circuit boards, due to the thicker copper thickness, its thermal conductivity is stronger. When mounted under the same conditions, ordinary Tg boards are more likely to have problems such as delamination, explosion, and white spot compared with high Tg boards.
2. Drilling
For thick copper circuit boards, due to the thick copper and the superposition of each layer, the copper is already at a large thickness. When drilling, the long-term friction of the drill in the board is likely to cause drill wear or breakage. , And then affect the quality of the hole wall, and further - affect the reliability of the product.
3. Line
For thick copper circuit boards, due to the thicker copper thickness, the processing difficulty is greater than that of ordinary boards when etching circuits. Therefore, increasing the line width and spacing during design will help reduce the difficulty of etching processing, and it will also greatly improve the lamination filling.
4. Lamination
For thick copper circuit boards, because the copper thickness is thicker, the thicker the copper thickness, the deeper the line gap. In the case of the same residual copper rate, the required amount of resin filling increases accordingly, and multiple prepregs (PP) are required to satisfy the filling. When the resin is less, it is easy to cause lack of glue and poor layering and board thickness uniformity;
Due to the superposition effect of the inner layer circuit and the limitation of resin flow during lamination of the thick copper circuit board, the area with a high residual copper rate after lamination will be thicker than the area with a low residual copper rate, resulting in a thicker circuit board. uneven. Therefore, the uniformity of copper laying on the inner layer should be improved as much as possible during design.
5. Solder mask
For thick copper circuit boards, due to the thicker copper thickness, problems such as substandard ink thickness, vertical flow, false copper exposure and air bubbles are prone to occur during solder mask production. In the industry, two solder mask printing and two exposure methods are usually used to achieve this. Our company now has electrostatic spraying equipment to support the effect better.
