Abstract: A method for forming a laser processed hole in a workpiece configured by bonding a transparent first member formed of a first material and a second member formed of a second material. The method includes holding the workpiece by a chuck table with a side of the first member directed upward; applying a pulsed laser beam to the workpiece from the upward side of the first member; detecting a wavelength of plasma light generated by applying the pulsed laser beam to the workpiece; and controlling the laser beam according to a detection signal from the plasma light. The plasma is detected by: passing only the wavelength of plasma light generated from the first material, and detecting the plasma light generated from the first material and outputting a light intensity signal based on the detection. The processed hole extends entirely through the first member without melting the second member.

Abstract: A laser processing method includes holding a single crystal silicon wafer as a workpiece, selecting a laser beam having a wavelength of 1950 nm or more in a transmission wavelength region to the single crystal silicon wafer, and applying the laser beam to the single crystal silicon wafer along a predetermined area with the focal point of the laser beam set inside the wafer, thereby forming a plurality of shield tunnels arranged along the predetermined area. Each shield tunnel is composed of a fine hole and an amorphous region formed around the fine hole for shielding the fine hole. The fine hole extends from a beam applied surface of the wafer where the laser beam is applied to the other surface opposite to the beam applied surface.

Abstract: A laser processing apparatus includes: a chuck table that holds a workpiece; a laser beam applying unit that applies a pulsed laser beam having a predetermined line width to the workpiece held by the chuck table; and a processing feeding unit that performs relative processing feeding of the chuck table and the laser beam applying unit. The laser beam applying unit includes: a laser oscillator that oscillates the pulsed laser beam; a focusing device that focuses the pulsed laser beam oscillated by the laser oscillator; and a pulse width adjustment unit that is disposed between the laser oscillator and the focusing device and that generates a time difference in a wavelength region of the pulsed laser beam in the predetermined line width, thereby adjusting the pulse width.

Abstract: A method of sorting chips divided from a plate-shaped workpiece into acceptable chips and defective chips includes an ultrasonic vibration applying step of applying ultrasonic vibrations to chips, a fracture confirming step of confirming whether the chips have been fractured in the ultrasonic vibration applying step or not, and a sorting step of sorting those chips which have been confirmed as not fractured in the fracture confirming step as acceptable chips. The ultrasonic vibrations applied to the chips in the ultrasonic vibration applying step are set to values that do not cause chips to be fractured if the chips are free of minute fractures and cause chips to be fractured if the chips contain minute fractures.

Abstract: A method of processing a wafer includes: preparing a support substrate that can transmit ultraviolet rays having a wavelength of 300 nm or shorter and can support the wafer thereon; integrating a face side of the wafer and the support substrate by sticking the face side of the wafer and the support substrate to each other with an UV-curable resin whose adhesive power can be lowered by ultraviolet rays applied thereto interposed therebetween, thereby integrally combining the wafer and the support substrate with each other; processing a reverse side of the wafer; destroying the UV-curable resin by applying a focused laser beam in an ultraviolet range having a wavelength of 300 nm or shorter from a support substrate side; and peeling off the support substrate from the face side of the wafer.

Abstract: A single-crystal substrate having a film deposited on a surface thereof is processed to divide the single-crystal substrate along a plurality of preset division lines, including a shield tunnel forming step of applying a pulsed laser beam having such a wavelength that permeates through the single-crystal substrate to the single-crystal substrate from a reverse side thereof along the division lines to form shield tunnels, each including a fine hole and an amorphous region shielding the fine hole, in the single-crystal substrate along the division lines, a film removing step of removing the film deposited on the single-crystal substrate along the division lines, and a dividing step of exerting an external force on the single-crystal substrate to which the shield tunnel forming step and the film removing step are performed to divide the single-crystal substrate along the division lines along which the shield tunnels have been formed.

Abstract: A method for detecting an internal crack in a wafer includes a first image recording step of applying near infrared light having a transmission wavelength to a reference wafer having the same configuration as a target wafer to be subjected to the detection of the internal crack, thereby obtaining a first image of the reference wafer having no internal crack and then recording the first image, a processing step of processing the target wafer, a second image recording step of applying the near infrared light to the target wafer, thereby obtaining a second image of the processed target wafer and then recording the second image, and an internal crack detecting step of removing the same image information between the first image and the second image from the second image to obtain a residual image, thereby detecting the residual image as the internal crack in the target wafer.

Abstract: Disclosed herein is a processing method of a single-crystal substrate having a film formed on a front side or a back side thereof to divide the single-crystal substrate along a plurality of preset division lines. The method includes a film removing step of removing the film along the division lines, a shield tunnel forming step of applying a pulsed laser beam having a wavelength which permeates through the single-crystal substrate along the division lines to form shield tunnels, each including a fine hole and an amorphous region shielding the fine hole, in the single-crystal substrate along the division lines, and dividing step of exerting an external force on the single-crystal substrate to which the shield tunnel forming step is performed to divide the single-crystal substrate along the division lines.

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 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: Disclosed herein is a laser processing method including a first application step of applying a first laser beam having a pulse width shorter than time of electron excitation generated by application of a laser beam to a workpiece, and a second application step of applying a second laser beam within the electron excitation time.

Abstract: A laser beam irradiation unit of a laser processing apparatus includes: a laser oscillator in which a repetition frequency is set so as to oscillate a pulsed laser having a pulse width shorter than a time of electronic excitation caused by irradiating the workpiece with a laser beam and oscillate at least two pulsed lasers within the electronic excitation time; a condenser that irradiates the workpiece held on the chuck table with the pulsed laser beams oscillated by the laser oscillator; and a thinning-out unit that is disposed between the laser oscillator and the condenser and guides the pulsed laser beams necessary for processing to the condenser by thinning out and discarding pulsed laser beams in a predetermined cycle.

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 processing method for a wafer including a crack detection step for irradiating illumination of a wavelength transparent to wafer, picking up an image of the wafer, and detecting whether a crack is generated within the wafer, a crack direction verification step for verifying, when a crack is detected, to which one of the first and second directions a direction in which the crack extends is nearer, a first cutting step for positioning the cutting blade to a scheduled division line of a direction decided to be a direction farther from the direction in which the crack extends from between the first and second directions and cutting the scheduled division line, and next a second cutting step for positioning the cutting blade to a scheduled division line of a direction decided to be nearer to the direction in which the crack extends and cutting the scheduled division line.

Abstract: 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, includes 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 modified regions in the substrate, each modified region extending at least from the first surface towards the second surface. Each modified region is formed by melting substrate material by means of the pulsed laser beam and allowing the molten substrate material to resolidify. The method further comprises removing substrate material along the at least one division line where the plurality of modified regions has been formed.

Abstract: A substrate has a first surface with at least one division line formed thereon and a second surface opposite the first surface. The substrate is processed by applying a pulsed laser beam from the side of the first surface. The substrate is transparent to the pulsed laser beam. The pulsed laser beam is applied at least in a plurality of positions along the at least one division line, a focal point of the pulsed laser beam located at a distance from the first surface in the direction from the first surface towards the second surface, so as to form a plurality of modified regions inside the substrate. Each modified region is entirely within the bulk of the substrate, without any openings open to the first surface or the second surface. Substrate material is removed along the at least one division line where the modified regions are present.

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: A method for detecting an internal crack in a wafer includes a first image recording step of applying near infrared light having a transmission wavelength to a reference wafer having the same configuration as a target wafer to be subjected to the detection of the internal crack, thereby obtaining a first image of the reference wafer having no internal crack and then recording the first image, a processing step of processing the target wafer, a second image recording step of applying the near infrared light to the target wafer, thereby obtaining a second image of the processed target wafer and then recording the second image, and an internal crack detecting step of removing the same image information between the first image and the second image from the second image to obtain a residual image, thereby detecting the residual image as the internal crack in the target wafer.

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 method of sorting chips divided from a plate-shaped workpiece into acceptable chips and defective chips includes an ultrasonic vibration applying step of applying ultrasonic vibrations to chips, a fracture confirming step of confirming whether the chips have been fractured in the ultrasonic vibration applying step or not, and a sorting step of sorting those chips which have been confirmed as not fractured in the fracture confirming step as acceptable chips. The ultrasonic vibrations applied to the chips in the ultrasonic vibration applying step are set to values that do not cause chips to be fractured if the chips are free of minute fractures and cause chips to be fractured if the chips contain minute fractures.