Patent ID: 6657159
Filing Date: 2003-12-02
Classification: B23K,H05K

Abstract:
A method for drilling vias in a multilayered structure comprising a first conductive layer and an underlying dielectric layer, comprising:removing the first conductive layer of the multilayered structure using a first laser, the first laser being configured to emit a first energy beam at a first wavelength and to focus the first energy beam to a first spot for removing the first conductive layer, the first spot having a first diameter which is less than a diameter of a via hole to be drilled; removing the underlying dielectric layer of the multilayered structure using a second laser, the second laser being configured to emit a second energy beam at a second wavelength and to focus the second energy beam to a second spot having a second diameter which is equal to or greater than the diameter of the via hole to be drilled; and, directing the first spot in a trepanning motion for completely removing the first conductive layer of the multilayered structure to the diameter of the via hole to be drilled, and for removing a portion of the underlying dielectric layer.