It is recommended to choose a high Tg plate. For thick copper circuit boards, due to the thick copper, the thermal conductivity is strong. When mounting under the same conditions, ordinary Tg boards are more prone to problems such as layered bursting and white spots than high Tg boards.
2. PCB drilling
For the thick copper board PCB, due to the thick copper and the superposition of various layers, the copper is already at a large thickness. During drilling, the friction of the drill in the board for a long time is prone to wear or break the drill , And then affect the quality of the hole wall, and further affect the reliability of the product.
3. PCB circuit
For the thick copper board PCB board, because the copper thickness is thicker, when etching the circuit, the processing difficulty is greater than the ordinary board. Therefore, increasing the width of the line width during design helps reduce the difficulty of etching processing, and also has a greater improvement in laminating and filling.
4. PCB Lamination
For the thick copper board PCB board, because the copper thickness is thicker, the thicker the copper thickness, the deeper the line gap. When the residual copper rate is the same, the required resin filling amount increases accordingly, and multiple prepregs (PP) are needed to satisfy the glue filling. When there is less resin, it is easy to cause the lack of glue delamination and poor thickness uniformity.
Thick copper pcb board during lamination due to the superimposition effect of the inner layer circuit and the limitation of resin flow, will cause the board thickness to be thicker in areas with high copper residue rate after lamination than in areas with low copper residue rate, resulting in PCB board thickness Uneven. Therefore, in the design, the inner layer copper uniformity should be improved as much as possible.
5. PCB solder mask
For thick copper PCBs, due to the thick copper thickness, problems such as substandard ink thickness, vertical flow, false exposed copper and bubbles are likely to occur during solder mask production. The industry usually adopts two solder mask printing and two exposure methods. Now there is better support for electrostatic spraying equipment.