Multilayer PCB Speedy Circuits Fabrication
Minimum Line Width : 3MIL ;
Minimum Line Spacing : 3MIL ;
Drilling Diameter : ≥ 0.1mm ;
Processing Size : 600 * 1200mm
Plate Thickness : 0.1-10mm ;
Processing Layers : 2-20 layers;
Special Process : Thick gold plate, ultra thick plate, depth control drilling, back drilling, hole filling electroplating, copper slurry plug hole, mechanical blind hole, etc.
Surface Treatment Processes : Include OSP, gold precipitation, silver precipitation, tin precipitation, gold plating, pure gold plating, thick gold plating, nickel palladium gold plating, nickel plating, tin plating, tin spraying, etc.
Compared with the product characteristics of conventional PCB boards, multi-layer high frequency PCB boards have thicker boards, more layers, lines and holes are more dense, the unit size is larger, the dielectric layer is thinner and other characteristics of the inner layer of space, the degree of alignment between the layers, impedance control, and reliability requirements are more stringent. What are the difficulties in the production of multi-layer high frequency PCB board?
a, The Inner Layer Line Production Difficulties
Multilayer board line has a high-speed, thick copper, high frequency, high Tg value of various special requirements, the inner layer of wiring and graphic size control requirements are increasingly high. For example, ARM development board, the inner layer has a very large number of impedance signal lines, to ensure the integrity of the impedance increases the difficulty of the inner layer line production.
The inner layer of signal lines, line width and spacing are basically in the 4 mil or less; board layers of multiple core board thin production is easy to wrinkle, these factors will increase the production cost of the inner layer.
b, The Inner Layer Between The Alignment Difficulties
More and more layers of multilayer boards, the inner layer of the alignment requirements are getting higher and higher. FILM by the workshop environment temperature and humidity will have the effect of rise and fall, the core board production will have the same rise and fall, which makes the precision of the alignment between the inner layer is more difficult to control.
c, Difficulties in Pressing Process
Multiple core boards and PP (semi-cured sheet) superposition, in the press-fit is prone to delamination, slippery boards and steam bag residue and other problems. The number of layers is large, the control of rise and shrinkage and size coefficient compensation can not maintain consistency; thin insulation layer between the layers, it is easy to lead to the failure of inter-layer reliability test problems.
d, Difficulties in Drilling Production
Multilayer board with high Tg or other special plates, different materials drilling roughness is not the same, increasing the difficulty of removing the glue residue in the hole. High-density multilayer board hole density, low productivity, easy to break the knife, different networks over the hole between the hole, the hole edge is too close will lead to CAF effect problems.
Multilayer high frequency PCB board its processing difficulty, its quality and reliability requirements, widely used in communications equipment, high-end servers, medical electronics, aviation, industrial control, military and other fields.