Definition

Drilling creates holes for vias, through-hole components, and mounting. Mechanical drilling uses carbide or diamond-coated bits spinning at 100,000+ RPM, achieving minimum diameters around 0.15-0.2mm in production. Laser drilling (CO2 or UV) creates micro-vias (0.075-0.15mm) by ablating material layer by layer. Drill registration, positional accuracy, and hole wall quality are critical. Entry and backup materials reduce burrs and improve hole quality. Drill wear affects hole quality in production runs.