Patent ID: 8729426
Filing Date: 2014-05-20
Classification: B23K,H05K,Y10T

Abstract:
1. Apparatus for the formation by laser ablation of relatively narrow grooves and relatively wide areas and/or holes in the surface of a dielectric layer comprising: laser apparatus for providing a first laser beam that is strongly absorbed by the dielectric layer and has substantially diffraction limited beam quality and which operates continuously or quasi-continuously for direct writing of the grooves and a second laser beam that is strongly absorbed by the dielectric layer and which operates in pulsed mode for forming the areas and/or holes via an image of an aperture or mask or via focal spot shaping; a common optical path comprising a beam scanner for deflecting the first and second laser beams in two orthogonal axes relative to the dielectric layer and a lens for focusing the first laser beam onto the surface of the dielectric layer and, when the second laser beam is used, for forming an image of said aperture or mask on the surface of the dielectric layer or for forming a shaped focal spot on the surface of the dielectric layer; and a control system arranged, in a first step, to drive the beam scanner so that a focused spot of the first laser beam is moved so as to vaporize the dielectric material to form relatively narrow grooves in the surface thereof and, in a second step, to drive the beam scanner so that a relatively wide laser spot from the second laser beam is incident on the surface of the dielectric layer and is moved to form relatively wide areas of defined depth in the surface thereof and/or is moved between a series of defined locations and the second laser beam held stationary at each location and a burst of laser pulses of sufficient number and energy is fired such that the dielectric material is vaporized to form a relatively wide hole of defined depth.