US 6,787,732 B1 · Method for laser-scribing brittle substrates and apparatus therefor

Abstract

A method of separating a sheet of a brittle material into portions by means of laser-scribing, comprising steps of: (a) providing a sheet of a brittle material having first and second opposing major surfaces separated by a thicknesst; (b) providing a source of laser energy adjacent said first surface, adapted for supplying a focussed beam of laser energy converging to a focal spot in a plane parallel to the first surface; (c) irradiating the sheet of brittle material with the focussed beam of laser energy, the plane of the focal spot of the beam initially being positioned within the sheet just below the first surface; and (d) continuing irradiating while simultaneously providing relative movement between the focal spot of the laser beam and the sheet to move the focal spot at a pre-selected rate and path extending over the first surface, and moving the depth of the plane of the focal spot at a pre-selected rate through a major portion of thickness t of the sheet to form a micro-crack zone extending along the pre-selected path from just below the first surface to a shallow depth just below the second surface.

Claims20

Dependent claims

A method of separating a sheet of a brittle material into portions by means of laser-scribing, comprising steps of:

(a) providing a sheet of a brittle material having first and second opposing major surfaces separated by a thickness t;
(b) providing a source of laser energy adjacent one of said first and second surfaces, said laser energy source adapted for supplying a focussed beam of laser energy converging to a focal spot in a plane parallel to said one surface;
(c) irradiating said sheet of brittle material with said focussed beam of laser energy from said source, said plane of said focal spot of said laser beam initially being positioned within said sheet just below said first surface thereof;
and
(d) continuing said irradiating while simultaneously:
(1) providing relative movement between said focal spot of said laser beam and said sheet to move said focal spot at a pre-selected rate along a pre-selected path extending over said first surface, and (2) moving the depth of said plane of said focal spot at a pre-selected rate through a major portion of said thickness t of said sheet to form a micro-crack zone extending along said pre-selected path from just below said first surface to a shallow depth just below said second surface.

3 more elements

An apparatus for performing laser-scribing of a sheet of material, comprising:

(a) a mounting means for mounting a sheet of a material having first and second opposing major surfaces having a thickness t;
(b) a pulsed UV laser source adapted for supplying a focussed beam of laser energy converging to a focal spot in a plane parallel to said first surface of said sheet of material;
(c) means for providing relative movement between said focal spot of said laser beam and said sheet for moving said beam at a pre-selected rate along a pre-selected path extending over said first surface of said sheet of material;
and
(d) means for moving the depth of said plane of said focal spot of said laser beam at a pre-selected rate through a major portion of said thickness of said sheet of material from a depth near said first surface to a depth nearer said second surface.

2 more elements

Dependencies are inferred from the claim text.

Method for laser-scribing brittle substrates and apparatus therefor

Life of this patent

Method for laser-scribing brittle substrates and apparatus therefor

Life of this patent

Abstract

Claims20