Nov 05, 2019 Backdrill is the process of creating vias by removing the stub in multilayer_ed printed wiring boards, to allow signals to flow from one layer of the board to another. It is a special craftsmanship of control depth drilling.
Advantages:
- Reduce interference of other signal
- Improve signal integrity
- Reduce partial plate thickness
- Reduce the use of blind and buried vias to reduce the difficulty of PCB fabrication
General Characteristics
- Mostly are rigid boards on back
- Normally used on 8 layers or above
- Board thickness is over 2.5mm
- Minimum hold size is 0.3mm
- Backdrill is 0.2mm larger than the vias
- Tolerance of backdrill depth+/-0.05MM
