Format Specification
Digital coordinates instruct automated drilling machines on where to pierce a printed circuit board substrate during manufacturing. Gerber drill files contain the precise spatial information, tool sizes, and feed rates required to create plated through-holes and via holes. These numeric files accompany the copper layer artwork files to ensure that each hole aligns perfectly with its mating pad.
In modern fabrication, the drill file format uses standard drill data blocks to coordinate complex multi-layer designs. This standardization prevents alignment errors between different design software tools and makes it possible for the factory to run automated checks before production begins.
Drilling Process
Automated machines read the file instructions to select the correct drill bits and execute the boring sequence. In the fabrication area, Gerber drill files dictate which holes are plated with copper and which remain non-plated. The drill file also specifies the depth of blind and buried vias, which are critical for high-density boards.
Correct feed speeds and spindle rotation parameters are derived from the tool definitions in the header of the file. This process secures the structural connection of the layers.
File Verification
Fabricators run digital simulations to verify the drill files against the copper Gerber layers before start of production. This check identifies misaligned holes or missing pads that would result in defective circuits. Software compares the drill layout with the circuit netlist to prevent open circuits or shorts.
The step ensures that no drilling is performed without matching copper contacts.
