1. Multilayer circuit board is a kind of printed circuit board that is laminated and bonded by alternating conductive pattern layers and insulating materials. The number of conductive pattern layers is more than three, and the electrical interconnection between layers is realized through metalized holes.
2. Comparing the production processes of the two parties, the multilayer fasts PCB board has added several process steps such as inner layer imaging, blackening, lamination, hatchback, and de-drilling.
3. Multi-layer PCB boards are more stringent than double-sided boards in some process parameters, equipment accuracy, and complexity. For example, multi-layer boards have stricter requirements on the quality of hole walls than double-layer boards, so the requirements for drilling are higher.
4. The number of stacks of each drilling of the multi-layer flex PCBA board, the speed, and the feed rate of the drill bit during drilling are different from the double-sided board.
5. The inspection of finished and semi-finished multi-layer circuit boards is much stricter and more complicated than double-sided boards.
6. Due to the complex structure of the multi-layer electronic pcba board, the glycerin hot-melt process with uniform temperature is adopted; the infrared hot-melt process that may cause local temperature rise is not used.