Laser beam machining method for wiring board, laser beam machining apparatus for wiring board, and carbonic acid gas laser oscillator for machining wiring board

摘要

In a laser beam machining method for a wiring board, a machined portion of the wiring board is irradiated with a pulsed laser beam for a beam irradiation time ranging from about 10 to about 200 &mgr;s and with energy density of about 20 J/cm² or more, thereby machining the wiring board, for example, drilling for a through-hole and a blind via hole, grooving, and cutting for an outside shape.