Abstract: A SiC wafer is produced from an SiC ingot having an end surface by setting the focal point of a laser beam at a predetermined depth from the end surface. The depth corresponds to the thickness of the SiC wafer to be produced. The laser beam is applied to the end surface of the SiC ingot while relatively moving the focal point and the SiC ingot to thereby form a modified layer parallel to the end surface and cracks extending from the modified layer, thus forming a separation start point. The separation start point is formed by setting the numerical aperture of a focusing lens to form the focal point to 0.45 to 0.9 and substantially setting the M2 factor of the laser beam between 5 and 50 to thereby set the diameter of the focal point to 15 to 150 ?m.

Abstract: A SiC wafer is produced from an SiC ingot having an end surface by setting the focal point of a laser beam at a predetermined depth from the end surface. The depth corresponds to the thickness of the SiC wafer to be produced. The laser beam is applied to the end surface of the SiC ingot while relatively moving the focal point and the SiC ingot to thereby form a modified layer parallel to the end surface and cracks extending from the modified layer, thus forming a separation start point. The separation start point is formed by setting the numerical aperture of a focusing lens to form the focal point to 0.45 to 0.9 and substantially setting the M2 factor of the laser beam between 5 and 50 to thereby set the diameter of the focal point to 15 to 150 ?m.

Abstract: The present invention provides a laser processing method in which a modified layer is formed inside a workpiece by irradiating the workpiece with a laser beam having such a wavelength as to be transmitted through the workpiece with the focal point of the laser beam positioned inside the workpiece. In the laser processing method, the spectral line width of the laser beam is set equal to or smaller than 10 pm.

Abstract: The present invention provides a laser processing method in which a modified layer is formed inside a workpiece by irradiating the workpiece with a laser beam having such a wavelength as to be transmitted through the workpiece with the focal point of the laser beam positioned inside the workpiece. In the laser processing method, the spectral line width of the laser beam is set equal to or smaller than 10 pm.

Abstract: A laser beam processing machine is provided which includes a laser beam irradiation unit including a laser beam oscillation unit and a processing head provided with a condenser lens condensing a laser beam oscillated from the laser beam oscillation unit. The processing head includes a liquid column forming mechanism provided with a jet nozzle adapted to jet liquid along an optical path for the laser beam condensed by the condenser lens, and a water droplet suction mechanism disposed below the liquid column forming mechanism and provided with an insertion passage through which a liquid column jetted from the jet nozzle is passed and with an annular suction port formed to surround the insertion passage and communicate with suction means.

Abstract: A laser beam processing machine is provided which includes a laser beam irradiation unit including a laser beam oscillation unit and a processing head provided with a condenser lens condensing a laser beam oscillated from the laser beam oscillation unit. The processing head includes a liquid column forming mechanism provided with a jet nozzle adapted to jet liquid along an optical path for the laser beam condensed by the condenser lens, and a water droplet suction mechanism disposed below the liquid column forming mechanism and provided with an insertion passage through which a liquid column jetted from the jet nozzle is passed and with an annular suction port formed to surround the insertion passage and communicate with suction means.

Abstract: A laser processing method for a wafer such that a laser beam is applied to a work surface of the wafer along a separation line formed on the work surface to thereby form a laser processed groove along the separation line on the work surface by ablation. The laser processing method includes a protective material coating step for coating the work surface of the wafer with a liquid protective material mainly containing a water-soluble silicone oil and a laser processed groove forming step for applying the laser beam to the work surface coated with the protective material along the separation line in the condition that the protective material has fluidity, thereby forming the laser processed groove along the separation line.

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 grooves along streets by applying a pulse laser beam along the streets for sectioning a plurality of devices of a wafer having the plurality of devices which are composed of a laminate consisting of an insulating film and a functional film, on the front surface of a substrate, wherein the pulse laser beam is set to have a repetition frequency of 150 kHz to 100 MHz and an energy per unit length of 5 to 25 J/m.

Abstract: In a wafer dividing method of dividing a wafer into individual devices, the wafer being sectioned by streets to form the devices each made of a laminated body in which an insulating film and a function film are laminated on a front surface of a semiconductor substrate, the method includes a laser processing groove forming step for forming a laser processing groove on the laminated body so as to reach the semiconductor substrate by applying a laser beam formed with an annular spot to the laminated body side of the wafer along the street, the annular spot having an outer diameter larger than a width of a cutting blade and smaller than a width of the street; and a cutting step for allowing a cutting blade to cut the semiconductor substrate of the semiconductor wafer along the laser processing groove formed at the street.

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.

Abstract: A silicon wafer laser processing method for forming a deteriorated layer along dividing lines formed on a silicon wafer in the inside of the silicon wafer by applying a laser beam along the dividing lines, wherein the wavelength of the laser beam is set to 1,100 to 2,000 nm.

Abstract: In a wafer dividing method of dividing a wafer into individual devices, the wafer being sectioned by streets to form the devices each made of a laminated body in which an insulating film and a function film are laminated on a front surface of a semiconductor substrate, the method includes a laser processing groove forming step for forming a laser processing groove on the laminated body so as to reach the semiconductor substrate by applying a laser beam formed with an annular spot to the laminated body side of the wafer along the street, the annular spot having an outer diameter larger than a width of a cutting blade and smaller than a width of the street; and a cutting step for allowing a cutting blade to cut the semiconductor substrate of the semiconductor wafer along the laser processing groove formed at the street.

Abstract: A laser processing apparatus comprising a chuck table, laser beam irradiation means for irradiating a workpiece held on the chuck table with a laser beam, and processing feed means for processing-feeding the chuck table and the laser beam irradiation means relative to each other. The laser beam irradiation means includes first laser beam irradiation means for throwing a first pulsed laser beam having a wavelength in the intermediate-infrared radiation region, and second laser beam irradiation means for throwing a second pulsed laser beam having a wavelength in the ultraviolet radiation region. The first laser beam irradiation means and the second laser beam irradiation means are set such that at least a part, in the processing feed direction, of the focus spot of the second pulsed laser beam overlaps the focus spot of the first pulsed laser beam.

Abstract: A method of dividing, along dividing lines, a wafer having function elements formed in areas sectioned by the dividing lines formed in a lattice pattern on the front surface, comprising: a frame holding step for affixing the back surface of the wafer to a dicing tape mounted on an annular frame; a deteriorated layer forming step for forming a deteriorated layer along the dividing lines in the inside of the wafer by applying a pulse laser beam capable of passing through the wafer to the wafer along the dividing lines, from the side of the front surface of the wafer held on the frame; a dividing step for dividing the wafer into individual chips along the dividing lines by exerting external force along the dividing lines where the deteriorated layers have been formed of the wafer held on the frame; an expansion step for enlarging the interval between chips by stretching the dicing tape affixed to the wafer divided into individual chips; and a picking up step for picking up each chip from the expanded dicing tape

Abstract: Disclosed herein is a processing apparatus using a laser beam, which includes a holder for holding a workpiece, and laser beam applicator for irradiating the workpiece, held by the holder, with a pulsed laser beam capable of passing through the workpiece, thereby deteriorating the workpiece. The laser beam applicator includes a pulsed laser beam oscillator and a transmitter/focuser for transmitting and focusing the pulsed laser beam oscillated by the pulsed laser beam oscillator. The transmitter/focuser focuses the pulsed laser beam, with a time difference provided, to at least two focus points that are displaced in the optical axis direction.

Abstract: A laser processing method for a wafer such that a laser beam is applied to a work surface of the wafer along a separation line formed on the work surface to thereby form a laser processed groove along the separation line on the work surface by ablation. The laser processing method includes a protective material coating step for coating the work surface of the wafer with a liquid protective material mainly containing a water-soluble silicone oil and a laser processed groove forming step for applying the laser beam to the work surface coated with the protective material along the separation line in the condition that the protective material has fluidity, thereby forming the laser processed groove along the separation line.

Abstract: A method of dividing a silicon wafer along predetermined dividing lines, comprising a deteriorated layer forming step for forming deteriorated layers exposed to at least a surface to which a laser beam is applied, from the inside of the silicon wafer by applying a pulse laser beam with a wavelength capable of passing through the silicon wafer to the silicon wafer along the dividing lines; and a dividing step for dividing the silicon wafer along the dividing lines by applying a laser beam having absorptivity for the silicon wafer to the silicon wafer along the dividing lines where the deteriorated layers have been formed, from the side to which the deteriorated layers have been exposed, to generate thermal stress along the dividing lines.

Abstract: A wafer laser processing method for forming grooves along streets by applying a pulse laser beam along the streets for sectioning a plurality of devices of a wafer having the plurality of devices which are composed of a laminate consisting of an insulating film and a functional film, on the front surface of a substrate, wherein the pulse laser beam is set to have a repetition frequency of 150 kHz to 100 MHz and an energy per unit length of 5 to 25 J/m.