A laser-assisted method embeds luminescent taggant particles in the surface of a substrate to provide a covert method of evaluating the authenticity of articles so treated.

A laser processing method includes a laser light emitting step of emitting a pulsed laser light along a line from a back surface of a target having a functional element layer on side of a front surface. The laser light emitting step includes: a first step of irradiating the functional element layer with a first pulsed laser light along the line, to form a weakened region in the functional element layer along the line; and a second step of emitting a second pulsed laser light into the target to follow the first pulsed laser light along the line, to form a crack reaching the front surface along the line in the target. The first pulsed laser light has a pulse width that is shorter than a pulse width of the second pulsed laser light.

A laser processing method includes a laser light emitting step of emitting a pulsed laser light along a line from a back surface of a target having a functional element layer on side of a front surface. The laser light emitting step includes: a first step of irradiating the functional element layer with a first pulsed laser light along the line, to form a weakened region in the functional element layer along the line; and a second step of emitting a second pulsed laser light into the target to follow the first pulsed laser light along the line, to form a crack reaching the front surface along the line in the target. The first pulsed laser light has a pulse width that is shorter than a pulse width of the second pulsed laser light.

In one example, a system can comprise a laser assisted bonding (LAB) tool comprising a stage block and a laser source facing the stage block. The stage block can be configured to support a first substrate and a first electronic component coupled with the first substrate, the first electronic component comprising a first interconnect. The laser source can be configured to emit a first laser towards the stage block to induce a first heat on the first interconnect to bond the first interconnect with the first substrate. Other examples and related methods are also disclosed herein.

In one example, a system can comprise a laser assisted bonding (LAB) tool comprising a stage block and a laser source facing the stage block. The stage block can be configured to support a first substrate and a first electronic component coupled with the first substrate, the first electronic component comprising a first interconnect. The laser source can be configured to emit a first laser towards the stage block to induce a first heat on the first interconnect to bond the first interconnect with the first substrate. Other examples and related methods are also disclosed herein.

A method of separating a coated substrate includes directing an infrared laser beam onto a first surface of the coated substrate. The coated substrate includes a coating layer disposed on a transparent workpiece, a plurality of defects is disposed within the coated substrate along a contour line that divides a primary region from a dummy region of the coated substrate from a dummy region of the coated substrate. The method also includes translating at least one of the coated substrate and the infrared laser beam relative to each other such that an infrared beam spot traces an oscillating pathway that follows an offset line in a translation direction and oscillates between an inner and outer track line, the oscillating pathway is disposed on the dummy region of the coated substrate, and the infrared laser beam applies thermal energy to the plurality of defects to induce separation of the coated substrate.

A method of separating a coated substrate includes directing an infrared laser beam onto a first surface of the coated substrate. The coated substrate includes a coating layer disposed on a transparent workpiece, a plurality of defects is disposed within the coated substrate along a contour line that divides a primary region from a dummy region of the coated substrate from a dummy region of the coated substrate. The method also includes translating at least one of the coated substrate and the infrared laser beam relative to each other such that an infrared beam spot traces an oscillating pathway that follows an offset line in a translation direction and oscillates between an inner and outer track line, the oscillating pathway is disposed on the dummy region of the coated substrate, and the infrared laser beam applies thermal energy to the plurality of defects to induce separation of the coated substrate.

A method of laser processing a transparent workpiece includes directing a pulsed laser beam into the transparent workpiece. The pulsed laser beam includes pulse bursts having 2 sub-pulses per pulse burst or more, each pulse burst of the pulsed laser beam has a burst duration T.sub.bd of 380 ns or greater; and the pulsed laser beam forms a pulsed laser beam focal line in the transparent workpiece, the pulsed laser beam focal line inducing absorption in the transparent workpiece, the induced absorption producing a defect in the transparent workpiece. The pulsed laser beam focal line includes a wavelength λ, a spot size w.sub.o, and a Rayleigh range Z.sub.R that is greater than

[00001]$F_D\frac{\pi w_o^2}{\lambda },$

where F.sub.D is a dimensionless divergence factor comprising a value of 10 or greater.

A method of laser processing a transparent workpiece includes directing a pulsed laser beam into the transparent workpiece. The pulsed laser beam includes pulse bursts having 2 sub-pulses per pulse burst or more, each pulse burst of the pulsed laser beam has a burst duration T.sub.bd of 380 ns or greater; and the pulsed laser beam forms a pulsed laser beam focal line in the transparent workpiece, the pulsed laser beam focal line inducing absorption in the transparent workpiece, the induced absorption producing a defect in the transparent workpiece. The pulsed laser beam focal line includes a wavelength λ, a spot size w.sub.o, and a Rayleigh range Z.sub.R that is greater than

[00001]$F_D\frac{\pi w_o^2}{\lambda },$

where F.sub.D is a dimensionless divergence factor comprising a value of 10 or greater.

A wafer processing method for processing a wafer with devices formed in regions on a side of a front surface of the wafer, the regions being defined by first scheduled division lines and second scheduled division lines includes a first modified layer forming step and a second modified layer forming step. In the first modified layer forming step, a laser beam is irradiated with its focal point set at a height leveled with a height of a first region located inside the wafer on the side of the front surface of the wafer, whereby first modified layers are formed. In the second modified layer forming step, the laser beam is irradiated with its focal point set at a height leveled with a height of a second region located inside the wafer on a side of a back surface of the wafer, whereby second modified layers are formed.