A first peel-off layer extending along a side surface of a truncated cone that has a first bottom surface positioned near a face side of a wafer and a second bottom surface positioned within the wafer and smaller in diameter than the first bottom surface, and a second peel-off layer extending along the second bottom surface of the truncated cone are formed in the wafer. Then, external forces are exerted on the wafer thicknesswise of the wafer, thereby dividing the wafer along the first peel-off layer and the second peel-off layer that function as division initiating points.

A wafer producing method includes a peel-off layer forming step of forming a peel-off layer by positioning a focused spot of a laser beam having a wavelength transmittable through an ingot to a depth corresponding to a thickness of the wafer to be produced from the ingot from a first end surface of the ingot and applying the laser beam to the ingot, a first chamfered portion forming step of forming a first chamfered portion by applying, from the first end surface side to a peripheral surplus region of the wafer, a laser beam having a wavelength absorbable by the wafer, a peeling-off step of peeling off the wafer to be produced, and a second chamfered portion forming step of forming a second chamfered portion by applying, from a peel-off surface side of the wafer, the laser beam having a wavelength absorbable by the wafer.

A method of operating an apparatus for laser annealing, includes reducing temporal or spatial coherency of a plurality of laser beams by beam superimposing; and reducing an electric field inner product magnitude of beams having the reduced temporal or spatial coherency by a fly eye lens array to reduce coherency, and/or by modifying a polarization state between the beams by beam superimposing.

A method of manufacturing an optionally shaped chip from a substrate having a crystalline structure includes establishing a projected dicing line on the substrate representing a contour of a chip to be fabricated from the substrate, and establishing a straight division assisting line contacting the contour of the chip for assisting in dividing the substrate. A division initiating point is formed after the projected dicing line is established and a laser beam is applied along the contour of the chip and the division assisting line while positioning a focused spot of the laser beam in the substrate at a predetermined position spaced from an upper surface of the substrate, thereby forming division initiating points in the substrate. The substrate is divided by applying external forces to the substrate in which the division initiating points have been formed, to divide the substrate along the division initiating points.

A substrate dividing method includes preparing a substrate that is formed with division start points along streets and that has a protective sheet attached to a surface on one side thereof and rolling a roller on a surface on the other side of the substrate, to attach an expanding tape. Next, suction by a holding table is cancelled, and, in a state in which a slight gap is formed between a holding surface of the holding table and the protective sheet, the roller is brought into contact with the expanding tape and rolled, thereby extending cracks extending from the division start points while causing the substrate to sink into the gap through the protective sheet with the division start points as starting points, and the expanding tape is expanded to widen the chip intervals with the division start points as starting points.

The invention relates to a method for cutting off at least one portion (4), in particular a wafer, from a solid body (2). The method comprises at least the following steps: modifying the crystal lattice of the solid body (2) by means of a modifier (18), wherein a number of modifications (19) are produced to form a nonplanar, in particular convex, detachment region (8) in the interior of the solid body, wherein the modifications (19) are produced in accordance with predetermined parameters, wherein the predetermined parameters describe a relationship between a deformation of the portion (4) and a defined further treatment of the portion (4), detaching the portion (4) from the solid body (2).

Laser processing of hard dielectric materials may include cutting a part from a hard dielectric material using a continuous wave laser operating in a quasi-continuous wave (QCW) mode to emit consecutive laser light pulses in a wavelength range of about 1060 nm to 1070 nm. Cutting using a QCW laser may be performed with a lower duty cycle (e.g., between about 1% and 15%) and in an inert gas atmosphere such as nitrogen, argon or helium. Laser processing of hard dielectric materials may further include post-cut processing the cut edges of the part cut from the dielectric material, for example, by beveling and/or polishing the edges to reduce edge defects. The post-cut processing may be performed using a laser beam with different laser parameters than the beam used for cutting, for example, by using a shorter wavelength (e.g., 193 nm excimer laser) and/or a shorter pulse width (e.g., picosecond laser).

A workpiece processing method includes holding a workpiece unit on a holding table and forming a division start point. The workpiece unit has a workpiece having a front side and a back side, and an additional member formed on the back side of the workpiece. The additional member is different in material from the workpiece. The workpiece unit is held on the holding table with the additional member opposed to the holding table. The division start point is formed by applying a laser beam to the front side of the workpiece with the focal point of the laser beam set inside the workpiece. The laser beam forms a modified layer inside the workpiece and simultaneously forming a division start point inside the additional member due to the leakage of the laser beam from the focal point toward the back side of the workpiece.

A laser processing machine includes a condenser and a water pillar forming unit. The condenser condenses a laser beam emitted from a laser oscillator and irradiates it to a workpiece held on a chuck table. The water pillar forming unit is disposed on a lower end of the condenser and is configured to form a thread-shaped water pillar on a front side of the workpiece. The laser oscillator includes a first laser oscillator, which emits a first laser beam having a short pulse width, and a second laser oscillator, which emits a second laser beam having a long pulse width. After the laser beams emitted from the first and second laser oscillators have transmitted through the thread-shaped water pillar formed by the water pillar forming unit and have been irradiated to the workpiece, a plasma occurred in the water pillar forming unit applies processing to the workpiece.

A device for producing and removing an internal contour from a planar substrate comprising: a beam-producing- and beam-forming arrangement which is configured to perform: a contour definition step wherein a laser beam is guided over the substrate to produce a plurality of individual zones of internal damage in a substrate material along a contour line defining the internal contour; a crack deformation step, wherein the laser beam is guided over the substrate and produces a plurality of individual zones of internal damage in the substrate material to form a plurality of crack line portions that lead away from the contour line into the internal contour; and a material removal-step, wherein a laser beam directed towards the substrate surface that inscribes a removal line through a thickness of the substrate at the internal contour causes the internal contour to detach from the substrate.