The design of multilayer PCB is much more complicated than singled sided PCB and doubled sided PCB. And in terms of manufacturing, the fabrication of multilayer circuit boards is also more difficult than standard PCB. Let’s take a look at what are the difficulties in manufacturing multilayer PCB board

1.The difficulty of inner copper layer.

a. Because of the special layer out of multilayer PCB board, most multilayer printed circuit boards use different material, for example, high TG, high speed, high frequency material, heavy copper prepreg and ultra-thin prepregs etc. These special materials will have demanding requirements for the inner copper pattern etching.

b.Because of smaller traces width and space on the multilayer PCB boards, there is more chances for open or short circuits with lower passing rates. And because of the small traces, the AOI might not detect the failure

c. The ultra-thin prepreg also caused some difficulty in multilayer PCB manufacturing. The thin prepreg will get rolled easily or exposure issue.

2.Lamination difficulty

In the lamination process, because of the special stack-up or material, there will be blister in the material or other lamination issue. So in the manufacturing multilayer rigid PCB boards, our engineer will take all data into consideration, for example material thermal stress, permittivity of the FR4 or prepreg, some times our engineer will provide the solutions of more prepregs for customer’s multilayer PCB stack-up.

3.Drilling difficulty.

Unlike single sided or double-sided PCBs, most multilayer PCB use high TG, high speed, high frequency or other special material, this will ask for demanding drilling technique of the printed circuit boards which will leave some burs inside the holes.

Linked Electronics Co., Limited, the one stop PCB supplier in China, are specialized in the high-speed PCB manufacturing, high frequency PCB manufacturing, HDI PCB fabrication. If you have PCB requirement such as multilayer PCB, aluminum PCB, Rogers PCB manufacturing etc, contact Linked Electronics, our team are very happy to help you to build your project.