Abstract: A laser processing method of applying a pulsed laser beam to a single crystal substrate to thereby process the single crystal substrate. The laser processing method includes a numerical aperture setting step of setting the numerical aperture (NA) of a focusing lens for focusing the pulsed laser beam so that the value obtained by dividing the numerical aperture (NA) of the focusing lens by the refractive index (N) of the single crystal substrate falls within the range of 0.05 to 0.

Abstract: A chip having a desired shape is formed from a platelike workpiece. The chip manufacturing method includes a shield tunnel forming step of applying a pulsed laser beam to the workpiece from a focusing unit included in a pulsed laser beam applying unit along the contour of the chip to be formed, with the focal point of the pulsed laser beam set at a predetermined depth from the upper surface of the workpiece, thereby forming a plurality of shield tunnels inside the workpiece along the contour of the chip to be formed. Each shield tunnel has a fine hole and an amorphous region formed around the fine hole for shielding the fine hole. In a chip forming step, ultrasonic vibration is applied to the workpiece to break the contour of the chip where the shield tunnels have been formed, thereby forming the chip from the workpiece.

Abstract: A lift-off method for transferring an optical device layer in an optical device wafer to a transfer substrate, the optical device layer being formed on the front side of an epitaxy substrate through a buffer layer. A transfer substrate is bonded through a bonding layer to the front side of the optical device layer of the optical device wafer, thereby forming a composite substrate. A pulsed laser beam having a wavelength transmissive to the epitaxy substrate and absorptive to the buffer layer is applied from the back side of the epitaxy substrate to the buffer layer, thereby breaking the buffer layer, and the epitaxy substrate is peeled from the optical device layer, thereby transferring the optical device layer to the transfer substrate. Ultrasonic vibration is applied to the composite substrate in transferring the optical device layer.

Abstract: A plate-shaped object processing method forms a through hole of a desired shape in a plate-shaped object. The method includes a through hole contour forming step of performing laser processing within the plate-shaped object along a contour of the through hole to be formed, by positioning, within the plate-shaped object, a focal point of a pulsed laser beam of a wavelength capable of passing through the plate-shaped object. The beam is applied along the contour of the through hole to be formed by a pulsed laser beam irradiation unit including a condenser applying the laser beams. A through hole is formed by breaking the laser-processed contour of the through hole and forming the through hole by positioning an ultrasonic transducer of an ultrasonic wave applying unit in correspondence with the contour of the through hole to be formed, and applying an ultrasonic wave.

Abstract: A laser processing method for performing laser processing to a workpiece. The laser processing method includes: a filament forming step of applying a first pulsed laser beam having a transmission wavelength to the workpiece to thereby form a filament as an optical transmission line in the workpiece so that the filament extends from the surface of the workpiece to be irradiated with the first pulsed laser beam to the inside of the workpiece, the filament having a refractive index higher than that of the workpiece; and a laser processing step of applying a second pulsed laser beam to the filament after performing the filament forming step to thereby transmit the second pulsed laser beam along the filament, thereby processing the workpiece with the second pulsed laser beam.

Abstract: A method of detecting a condensing spot position in a laser beam processing apparatus, including: a detection position setting step of setting a plurality of Z-axis directional positions in a range from a starting point to an ending point of detection positions into which the condenser is positioned; a laser beam processed groove forming step of sequentially positioning the condenser into the detection positions in the range from the starting point to the ending point, performing a predetermined interval indexing feeding by operating indexing feeding means each time the detection position for the condenser is changed, and forming a laser beam processed groove of a predetermined length in the plate-shaped body at each of the detection positions for the condenser; and a laser beam processed groove imaging step of imaging the laser beam processed grooves formed in the plate-shaped body by imaging means.

Abstract: In an optical device wafer processing method, a light emitting layer on the front side of a wafer is removed by applying a pulsed laser beam to the wafer along division lines from the back side of a substrate with the focal point of the beam set near the light emitting layer, thereby partially removing the light emitting layer along the division lines. A shield tunnel is formed by applying the beam to the wafer along the division lines from the back of the substrate with the focal point of the beam set near the front of the substrate. This forms a plurality of shield tunnels arranged along each division line, each shield tunnel extending from the front side of the substrate to the back side thereof. Each shield tunnel has a fine hole and an amorphous region formed around the fine hole for shielding the fine hole.

Abstract: A laser processing method of applying a pulsed laser beam to a single crystal substrate to thereby process the single crystal substrate. The laser processing method includes a numerical aperture setting step of setting the numerical aperture (NA) of a focusing lens for focusing the pulsed laser beam so that the value obtained by dividing the numerical aperture (NA) of the focusing lens by the refractive index (N) of the single crystal substrate falls within the range of 0.05 to 0.

Abstract: A wafer processing method for forming a via hole in a wafer. The wafer processing method includes a filament forming step of applying a pulsed laser beam to the wafer, the pulsed laser beam having a transmission wavelength to the wafer, in the condition where the focal point of the pulsed laser beam is set inside the wafer in a subject area where the via hole is to be formed, thereby forming an amorphous filament inside the wafer in the subject area, and an etching step of etching the amorphous filament formed inside the wafer by using an etching agent to thereby form the via hole inside the wafer.

Abstract: A wafer processing method for dividing a wafer along a plurality of division lines to obtain a plurality of individual chips. The wafer processing method includes a filament forming step of applying a pulsed laser beam having a transmission wavelength to the wafer along each division line in the condition where the focal point of the pulsed laser beam is set inside the wafer in a subject area to be divided, thereby forming a plurality of amorphous filaments inside the wafer along each division line, and an etching step of etching the amorphous filaments formed inside the wafer along each division line by using an etching agent to thereby divide the wafer into the individual chips along the division lines.

Abstract: A laser processing method for performing laser processing to a workpiece. The laser processing method includes: a filament forming step of applying a first pulsed laser beam having a transmission wavelength to the workpiece to thereby form a filament as an optical transmission line in the workpiece so that the filament extends from the surface of the workpiece to be irradiated with the first pulsed laser beam to the inside of the workpiece, the filament having a refractive index higher than that of the workpiece; and a laser processing step of applying a second pulsed laser beam to the filament after performing the filament forming step to thereby transmit the second pulsed laser beam along the filament, thereby processing the workpiece with the second pulsed laser beam.

Abstract: A laser beam processing method for a wafer includes a first processed groove forming step in which a laser beam is radiated along a planned dividing line so that the overlapping rate of condensed beam spots is equal to or less than 95%, to thereby form a first laser beam processed groove. The laser beam processing method for a wafer further includes a second processed groove forming step in which a laser beam is radiated along the first laser beam processed groove in such a manner that the overlapping rate of condensed beam spots is equal to or more than 97%, to thereby form a second laser beam processed groove at a bottom portion of the first laser beam processed groove.

Abstract: A method of detecting a condensing spot position in a laser beam processing apparatus, including: a detection position setting step of setting a plurality of Z-axis directional positions in a range from a starting point to an ending point of detection positions into which the condenser is positioned; a laser beam processed groove forming step of sequentially positioning the condenser into the detection positions in the range from the starting point to the ending point, performing a predetermined interval indexing feeding by operating indexing feeding means each time the detection position for the condenser is changed, and forming a laser beam processed groove of a predetermined length in the plate-shaped body at each of the detection positions for the condenser; and a laser beam processed groove imaging step of imaging the laser beam processed grooves formed in the plate-shaped body by imaging means.

Abstract: A device processing method for improving the die strength of a device divided from a semiconductor wafer. The device processing method includes a chamfering step of applying a pulsed laser beam having an absorption wavelength to the device along the periphery of the device to thereby chamfer the periphery of the device, wherein the pulse width of the pulsed laser beam to be applied in the chamfering step is set to 2 ns or less, and the peak energy density is set in the range of 5 to 200 GW/cm2.

Abstract: A laser processing method for a semiconductor wafer including a groove forming step of applying a pulsed laser beam having an absorption wavelength to the semiconductor wafer along a division line formed on the semiconductor wafer to thereby form a laser processed groove along the division lines on the semiconductor wafer, wherein the pulse width of the pulsed laser beam to be applied in the groove forming step is set to 2 ns or less, and the peak energy density is set in the range of 5 to 200 GW/cm2.

Abstract: A device processing method for improving the die strength of a device divided from a semiconductor wafer. The device processing method includes a chamfering step of applying a pulsed laser beam having an absorption wavelength to the device along the periphery of the device to thereby chamfer the periphery of the device, wherein the pulse width of the pulsed laser beam to be applied in the chamfering step is set to 2 ns or less, and the peak energy density is set in the range of 5 to 200 GW/cm2.

Abstract: A laser processing method for a semiconductor wafer including a groove forming step of applying a pulsed laser beam having an absorption wavelength to the semiconductor wafer along a division line formed on the semiconductor wafer to thereby form a laser processed groove along the division lines on the semiconductor wafer, wherein the pulse width of the pulsed laser beam to be applied in the groove forming step is set to 2 ns or less, and the peak energy density is set in the range of 5 to 200 GW/cm2.

Abstract: A laser beam processing machine comprising a chuck table for holding a workpiece, a laser beam application means for applying a laser beam to the workpiece held on the chuck table, and a processing-feed means for moving the chuck table and the laser beam application means relative to each other, wherein the chuck table comprises a body and a workpiece holding member disposed on the top surface of the body, and the workpiece holding member is made of a material which transmits a laser beam having a predetermined wavelength.

Abstract: A wafer laser processing method for forming a groove along streets in a wafer by moving the wafer at a predetermined feed rate while a laser beam whose focal spot is elliptic is applied along the streets formed on the wafer, comprising: a groove forming step for forming a groove along the streets by applying a first laser beam whose elliptic focal spot has a ratio of the long axis to the short axis of 30 to 60:1, along the streets formed on the wafer; and a debris removing step for removing debris accumulated in the groove by applying a second laser beam whose elliptic focal spot has a ratio of the long axis to the short axis of 1 to 20:1, along the groove formed by the groove forming step; the groove forming step and the debris removing step being repeated alternately.

Abstract: A wafer holding mechanism for holding a wafer affixed to a frame with a tape utilizing a suction force. The wafer holding mechanism includes a suction body, a wafer holder with a holding surface for holding the wafer via the tape, and a suction unit with a suction portion disposed at an outer peripheral edge of the wafer holder. The suction portion transmits a suction force across the holding surface though the outer peripheral edge of the wafer holder such that when the suction portion is covered and sealed by the tape, the wafer holder is held at the suction unit and the wafer is held at the holding surface.