Abstract: Disclosed herein is a wafer processing method including a cover plate providing step of providing a cover plate on the front side of a wafer to thereby form a composite wafer, a welding step of applying a laser beam along each division line formed on the front side of the wafer in the condition where the focal point of the laser beam is set at the interface between the wafer and the cover plate on opposite sides of the lateral center of each division line, thereby forming two parallel welded lines for joining the wafer and the cover plate along each division line, and a dividing step of forming a cut line between the two parallel welded lines formed along each division line, thereby cutting the composite wafer along each division line to obtain individual device chips each covered with the cover plate.

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: Disclosed herein is a wafer processing method including a cover plate providing step of providing a cover plate on the front side of a wafer to thereby form a composite wafer, a welding step of applying a laser beam along each division line formed on the front side of the wafer in the condition where the focal point of the laser beam is set at the interface between the wafer and the cover plate on opposite sides of the lateral center of each division line, thereby forming two parallel welded lines for joining the wafer and the cover plate along each division line, and a dividing step of forming a cut line between the two parallel welded lines formed along each division line, thereby cutting the composite wafer along each division line to obtain individual device chips each covered with the cover plate.

Abstract: Disclosed herein is an inspecting apparatus including an illuminating unit adapted to be positioned in the periphery of a transparent member for illuminating the transparent member from the outside of the circumference thereof, an imaging unit adapted to be opposed to the transparent member for imaging the transparent member illuminated by the illuminating unit, and a displaying monitor for displaying an image obtained by the imaging unit.

Abstract: A method of dividing a single-crystal substrate along a plurality of preset division lines, includes a shield tunnel forming step of applying a pulsed laser beam having such a wavelength that permeates through the substrate along the division lines to form shield tunnels, each including a fine hole and an amorphous region shielding the fine hole, a protective member adhering step of adhering a protective member to the substrate before or after the shield tunnel forming step, and a grinding step of holding the protective member on the substrate, to which the shield tunnel forming step and the protective member adhering step are performed, on a chuck table of a grinding apparatus, grinding a reverse surface of the substrate to bring the substrate to a predetermined thickness, and dividing the substrate along the division lines along which the shield tunnels have been formed.

Abstract: The invention relates to a method of processing a substrate, having a first surface with a device area and a second surface opposite the first surface, wherein the device area has a plurality of devices formed therein. The method comprises applying a pulsed laser beam to the substrate from the side of the second surface, in a plurality of positions along the second surface, so as to form a plurality of hole regions in the substrate, each hole region extending from the second surface towards the first surface. Each hole region is composed of a modified region and a space in the modified region open to the second surface. The method further comprises grinding the second surface of the substrate, where the plurality of hole regions has been formed, to adjust the substrate thickness.

Abstract: Disclosed herein is a method of forming a gettering layer for capturing metallic ions on the back side of a semiconductor wafer formed with devices on the face side thereof. The method includes irradiating the back-side surface of the semiconductor wafer with a pulsed laser beam having a pulse width corresponding to a thermal diffusion length of 10 to 230 nm, to thereby form the gettering layer.

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 wafer is divided into a plurality of individual devices along a plurality of division lines, the wafer being composed of a substrate and a functional layer formed on the upper surface of the substrate through a buffer layer. The functional layer is partitioned by the division lines to define a plurality of separate regions where the devices are formed on the front side of the wafer. At least the functional layer is cut along the division lines. A protective member is provided on the front side of the wafer. The buffer layer is broken by applying a laser beam having a transmission wavelength to the substrate with the focal point of the laser beam set in the buffer layer, thereby breaking the buffer layer. The substrate is peeled from the functional layer, thereby forming the individual devices from the functional layer.

Abstract: A method of processing a wafer includes placing a supporting substrate in confronting relation to a face side of the wafer and integrally bonding the supporting substrate to the face side of the wafer with a bonding material, grinding a reverse side of the wafer to thin the wafer, cutting the wafer along division lines from the reverse side of the wafer into chips that carry individual devices thereon, placing a protective member on the reverse side of the wafer, applying a laser beam having a wavelength which is able to transmit the supporting substrate in the condition where a focused spot of the laser beam is set in the bonding material, thereby breaking the bonding material, and peeling the supporting substrate off from the devices to separate the chips that carry the individual devices thereon.

Abstract: A laser processing method for forming a laser processed hole in a workpiece having a first member including a first material and a second member including a second material, the laser processed hole extending from the first member to the second member, the laser processing method including: applying a pulsed laser beam to the workpiece; using a plasma detecting means to detect the wavelength of plasma light generated by applying the pulsed laser beam to the workpiece; controlling, via a controller, a laser beam applying means according to a detection signal from the plasma detecting means; and stopping the application of the pulsed laser beam when both: (i) the light intensity detected by a first photodetector is decreased, and (ii) the light intensity detected by a second photodetector is increased to a peak value and next decreased to a given value that is slightly less than the peak value.

Abstract: A wafer is formed by slicing a single crystal ingot and removing crystal strains remaining in a peripheral portion of the wafer. In the crystal strain removing step, a laser beam having such a wavelength as to be transmitted through the wafer is applied to the wafer from one side of the wafer in positions located along the margin of the wafer and spaced a predetermined distance inward from the margin, to cause growth of fine holes and amorphous regions shielding the fine holes, over the range from one side to the other side of the wafer, whereby shield tunnels are formed in an annular pattern. Then, an external force is applied to the wafer along the shield tunnels so as to break the wafer in the region of the shield tunnels, thereby removing the peripheral wafer portion where the crystal strains are remaining.

Abstract: The invention relates to a method of processing a substrate, having a first surface with at least one division line formed thereon and a second surface opposite the first surface. The method comprises applying a pulsed laser beam to the substrate from the side of the first surface, at least in a plurality of positions along the at least one division line, so as to form a plurality of hole regions in the substrate, each hole region extending from the first surface towards the second surface. Each hole region is composed of a modified region and a space in the modified region open to the first surface. The method further comprises removing substrate material along the at least one division line where the plurality of hole regions has been formed.

Abstract: A focusing unit of a laser processing apparatus includes: a focusing lens that focuses a laser beam oscillated from a laser beam oscillating unit; and a spherical aberration extending lens that extends the spherical aberration of the focusing lens. A pulsed laser beam is applied from the focusing unit to a workpiece held on a chuck table, to form shield tunnels each composed of a fine hole and an amorphous region shielding the fine hole, the shield tunnels extending from an upper surface toward a lower surface of the workpiece.

Abstract: A method for processing a workpiece including: a supporting plate preparing step of preparing a supporting plate having, on a top surface side of the supporting plate, a recessed portion configured to house a projecting portion provided in a device region of the workpiece; a positioning step of mounting the workpiece on the supporting plate such that the recessed portion of the supporting plate and the device region of the workpiece correspond to each other; a bonding step of forming a welded region in which the workpiece is welded to the supporting plate by irradiating a peripheral surplus region of the workpiece mounted on the supporting plate with a laser beam, whereby the workpiece is fixed on the supporting plate; and a processing step of processing the workpiece after performing the bonding step.

Abstract: Disclosed herein is a wafer thinning method for thinning a wafer formed from an SiC substrate having a first surface and a second surface opposite to the first surface. The wafer thinning method includes an annular groove forming step of forming an annular groove on the second surface of the SiC substrate in an annular area corresponding to the boundary between a device area and a peripheral marginal area in the condition where a thickness corresponding to the finished thickness of the wafer after thinning is left, and a separation start point forming step of applying the laser beam to the second surface as relatively moving a focal point and the SiC substrate to thereby form a modified layer and cracks inside the SiC substrate at the predetermined depth.

Abstract: A method of processing a single-crystal member includes setting the peak energy density of a pulsed laser beam to a value in a range from 1 TW/cm2 to 100 TW/cm2, and applying the pulsed laser beam to the single-crystal member while positioning a converged point of the pulsed laser beam at a predetermined position spaced from an upper side of the single-crystal member to grow a fine hole and a amorphous region shielding the fine hole from the upper side of the single-crystal member, thereby forming a shield tunnel in the single-crystal member.

Abstract: A wafer is formed with a plurality of division lines on a front surface of a single crystal substrate having an off angle and formed with devices in a plurality of regions partitioned by the division lines. The wafer is processed by setting a numerical aperture (NA) of a focusing lens for focusing a pulsed laser beam so that a value obtained by dividing the numerical aperture (NA) by a refractive index (N) of the single crystal substrate falls within the range from 0.05 to 0.2. The pulsed laser beam is applied along the division lines, with a focal point of the pulsed laser beam positioned at a desired position from a back surface of the single crystal substrate, so as to form shield tunnels each composed of a pore and a pore-shielding amorphous portion along the division lines from the focal point positioned inside the single crystal substrate.

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 lift-off method transfers an optical device layer in an optical device wafer to a transfer substrate. The optical device layer is formed on the front side of an epitaxy substrate through a buffer layer. A composite substrate is formed by bonding the transfer substrate through a bonding agent to the front side of the optical device layer, thereby forming a composite substrate. The buffer layer is broken up by applying a laser beam having a wavelength transmissive to the epitaxy substrate and absorptive to the buffer layer from the back side of the epitaxy substrate to the buffer layer after performing the composite substrate forming step, thereby breaking the buffer layer. An optical device layer is transferred by peeling off the epitaxy substrate from the optical device layer after performing the buffer layer breaking step, thereby transferring the optical device layer to the transfer substrate.