About the process and critical control point for RO4000 series material.
Hello, I’m the technology manager of ChinaPCBOne, I have over ten years’ experience about process Roger material, now pls let me briefly introduce how the RO4000 series material laminated, process, and critical control point.
First, what is RO4000 material? It is a glass fiber reinforced ceramic laminated with low dielectric constant and low dielectric loss, stable electrical characteristics at different frequencies, excellent dimensional stability, etc.
Key control points for the process:
Storage: there is temperature requirement for stock RO4003C, RO4350B and other 4000 series of copper-clad substrates, the temperature is 10-32 degrees. the warehouse needs to use the "first in, first out" inventory system, and warehouse need to record the batch number of material during every purchaser to better track
About lamination, it is the same as FR4, using dry film or Photosensitive ink as anti-etching layer to make the pattern which within tolerance. Using the way of machine punching holes to add tooling hole to fix, then ensure the accuracy of fix location within+/-2mil. Using Amertech syrup to do browning before lamination so that can ensure the bonding force between prepreg and copper clad. Also, we can laminate FR4+Rogers material in mixture if the customer want to save cost, but need us pay more attention on the shrinking of material, and take different response on these two different material so that ensure the size is meet the requirement after laminating.
Drilling, there is no bid different with FR4, but the drill-bites lost more worse for Rogers than FR4. The engineer needs to adjust the drilling parameter and the usage time of drill-bite. We did control the parameter of different design and usage time.
Etching: this is a very important process. It will etching some copper which no need then get the circuit what we want. We can ensure the accuracy trace width when etching, using control +/-10% tolerance for the trace width which less than 0.2mm, if over 0.2mm, then we will control stricter than +/-10% which the range is +/-0.2mm. of course, this is the situation which enough compensate on the working gerber. If we can’t meet, we will come up EQ with our best solution.
Testing, High-speed flying probe test to ensure fast and good measurement of electrical performance
Profile: we can ensure the smooth outline within tolerance of the final product as we use the professional CNC equipment.
Packing- this is the last stagebut, we also can’t relax, every board we use vacuum packaging to ensure the board will not hurt during transport.
This is ChinaPCBOne, professional PCB manufacturer, you worth to try.