Abstract: A laser processing apparatus includes a laser oscillator that emits a laser beam, a beam condenser that condenses the laser beam emitted by the laser oscillator and positions the condensed point to a wafer, a condensed point position adjuster that is disposed between the laser oscillator and the beam condenser and adjusts the position of the condensed point, and an upper surface position detector that detects the upper surface position of the wafer. The upper surface position detector includes a detection light source that emits detection light of a wide wavelength band and a selector that selects detection light with a specific wavelength from the detection light emitted by the detection light source.

Abstract: A laser processing apparatus includes a laser beam applying unit for applying a laser beam to a wafer. The laser beam applying unit includes a laser oscillator for emitting the laser beam, a beam condenser for focusing the laser beam emitted from the laser oscillator into a focused spot and positioning the focused spot in the wafer held on a chuck table, a focused spot position adjuster disposed between the laser oscillator and the beam condenser for adjusting the position of the focused spot, and an upper surface position detector for detecting the position of an upper surface of the wafer. The upper surface position detector includes a first upper surface position detecting unit, a second upper surface position detecting unit, and a selector for selecting either the first upper surface position detecting unit or the second upper surface position detecting unit depending on a feature of the wafer.

Abstract: A spectral interference height detecting apparatus includes a chuck table for holding a workpiece thereon and a height detecting unit for detecting the height of an upper surface of the workpiece held on the chuck table. The height detecting unit includes a light source for emitting light in a predetermined wavelength band into a first optical path, a condenser disposed in the first optical path for converging light onto the workpiece held on the chuck table, a beam splitter disposed between the light source and the condenser for splitting the light in the first optical path into a second optical path, a mirror disposed in the second optical path to form a basic optical path length, for reflecting light into the second optical path and returning light through the beam splitter to the first optical path.

Abstract: A testing system for testing a workpiece for a characteristic by irradiating microwaves to the workpiece and also irradiating a laser beam at an irradiation position of the microwaves, receiving microwaves reflected at the irradiation position where the workpiece has a reflectivity increased by carriers generated through photoexcitation, and measuring a lifetime of the carriers. The testing system includes a chuck table that holds the workpiece, a microwave irradiation unit that irradiates the microwaves to the workpiece held on the chuck table, a microwave reception unit that receives microwaves reflected by the workpiece, and a laser beam irradiation unit that irradiates the laser beam onto the irradiation position to which the microwaves have been irradiated.

Abstract: A testing system for testing a workpiece for a characteristic by irradiating microwaves to the workpiece and also irradiating a laser beam at an irradiation position of the microwaves, receiving microwaves reflected at the irradiation position where the workpiece has a reflectivity increased by carriers generated through photoexcitation, and measuring a lifetime of the carriers. The testing system includes a chuck table that holds the workpiece, a microwave irradiation unit that irradiates the microwaves to the workpiece held on the chuck table, a microwave reception unit that receives microwaves reflected by the workpiece, and a laser beam irradiation unit that irradiates the laser beam onto the irradiation position to which the microwaves have been irradiated.

Abstract: Disclosed herein is a laser processing apparatus including first and second laser mechanisms, a laser oscillator for oscillating an original laser beam, an optical system for branching the original laser beam into first and second laser beams, and first and second operation panels for respectively setting first and second processing conditions for the first and second laser mechanisms. The first and second laser mechanisms include first and second chuck tables for holding first and second workpieces, first and second X moving units for moving the first and second chuck tables in an X direction, first and second Y moving units for moving the first and second chuck tables in a Y direction perpendicular to the X direction, and first and second focusing units for focusing the first and second laser beams to the first and second workpieces held on the first and second chuck tables, respectively.

Abstract: A laser processing apparatus includes a controller having (a) a section for storing the Y coordinate of a characteristic point having a predetermined positional relation to each division line formed on a wafer as a reference value with respect to a reference position where the focal point of a laser beam coincides with a predetermined position on each division line, (b) a section for detecting the amount of deviation of the Y coordinate of the characteristic point after indexing each division line of the wafer in the Y direction by the operation of a Y moving unit, from the Y coordinate stored as the reference value, and (c) a section for determining whether or not the amount of deviation detected is greater than an allowable value.

Abstract: A thickness measuring apparatus measures the thickness of a wafer. The apparatus includes a light source for emitting light having a transmission wavelength region to the wafer, a focusing unit for applying the light emitted from the light source to the wafer, a first optical path for optically connecting the light source to the focusing unit, an optical branching section provided on the first optical path for branching the light reflected on the wafer and then guiding the reflected light to a second optical path, a diffraction grating provided on the second optical path for diffracting the reflected light to obtain diffracted light of different wavelengths, an image sensor for detecting the intensity of the diffracted light according to the different wavelengths and producing a spectral interference waveform, and a control unit having a thickness computing section for computing the spectral interference waveform to output thickness information.

Abstract: A reflectance detection method in which a workpiece is irradiated with a laser beam and reflectance is detected, irradiating, with a light amount H0, the workpiece with a laser beam with a first wavelength X1 shorter than a detection-target wavelength X and detecting a light amount H1 of reflected return light, irradiating the workpiece with a laser beam with a second wavelength X2 longer than the detection-target wavelength X with the light amount H0 and detecting a light amount H2 of reflected return light, and employing H calculated based on an expression shown below as the light amount of return light obtained when the workpiece is irradiated with the detection-target wavelength X and calculating reflectance obtained when the workpiece is irradiated with the detection-target wavelength X based on H/H0.

Abstract: A spectral interference height detecting apparatus includes a chuck table for holding a workpiece thereon and a height detecting unit for detecting the height of an upper surface of the workpiece held on the chuck table. The height detecting unit includes a light source for emitting light in a predetermined wavelength band into a first optical path, a condenser disposed in the first optical path for converging light onto the workpiece held on the chuck table, a beam splitter disposed between the light source and the condenser for splitting the light in the first optical path into a second optical path, a mirror disposed in the second optical path to form a basic optical path length, for reflecting light into the second optical path and returning light through the beam splitter to the first optical path.

Abstract: A reflectance detection method in which a workpiece is irradiated with a laser beam and reflectance is detected, irradiating, with a light amount H0, the workpiece with a laser beam with a first wavelength X1 shorter than a detection-target wavelength X and detecting a light amount H1 of reflected return light, irradiating the workpiece with a laser beam with a second wavelength X2 longer than the detection-target wavelength X with the light amount H0 and detecting a light amount H2 of reflected return light, and employing H calculated based on an expression shown below as the light amount of return light obtained when the workpiece is irradiated with the detection-target wavelength X and calculating reflectance obtained when the workpiece is irradiated with the detection-target wavelength X based on H/H0.

Abstract: Disclosed herein is a laser processing apparatus including a controller. The controller includes a coordinate storing section for storing the Y coordinate of a characteristic point having a predetermined positional relation to each division line formed on a wafer as a reference value with respect to a reference position where the focal point of a laser beam to be focused by a focusing unit coincides with a predetermined position on each division line in a Y direction as an indexing direction, a deviation detecting section for detecting the amount of deviation of the Y coordinate of the characteristic point imaged by an imaging unit after indexing each division line of the wafer in the Y direction by the operation of a Y moving unit, from the Y coordinate stored as the reference value in the coordinate storing section, and a determining section for determining whether or not the amount of deviation detected by the deviation detecting section is greater than an allowable value.

Abstract: A laser processing apparatus includes a beam splitting unit disposed between a pulsed laser beam oscillating unit and a condenser. The beam splitting unit includes a half-wave plate that rotates the plane of polarization of a pulsed laser beam, a birefringent lens that splits the pulsed laser beam that has passed through the half-wave plate into ordinary light and extraordinary light, the birefringent lens being formed by joining two kinds of crystalline bodies to each other across a curved plane of a concave surface and a convex surface, and a splitting angle adjusting unit that moves the birefringent lens in a direction orthogonal to the pulsed laser beam that has passed through the half-wave plate to change the angle of incidence with respect to the curved plane and adjust a beam splitting angle.

Abstract: A laser processing apparatus includes a first chuck table for holding a first workpiece, moving units for moving the first chuck table in X and Y directions, and a first focusing unit for focusing a first laser beam to the first workpiece. A second chuck table holds a second workpiece. Other moving units move the second chuck table in the X direction and Y directions, and a second focusing unit focuses a second laser beam to the second workpiece. A laser oscillator produces an original laser beam, and an optical system branches the original laser beam into the first laser beam and the second laser beam, and leads the first and second laser beams to the first and second focusing units, respectively.

Abstract: Disclosed herein is a laser processing apparatus including first and second laser mechanisms, a laser oscillator for oscillating an original laser beam, an optical system for branching the original laser beam into first and second laser beams, and first and second operation panels for respectively setting first and second processing conditions for the first and second laser mechanisms. The first and second laser mechanisms include first and second chuck tables for holding first and second workpieces, first and second X moving units for moving the first and second chuck tables in an X direction, first and second Y moving units for moving the first and second chuck tables in a Y direction perpendicular to the X direction, and first and second focusing units for focusing the first and second laser beams to the first and second workpieces held on the first and second chuck tables, respectively.

Abstract: A laser machining apparatus that includes an interferometric height position detection unit, a condensing point position adjustment unit, and a confocal optical height position detection unit. A controller of the laser machining apparatus specifies, as a correction value, the difference between the two height positions of the upper face of the workpiece, one detected by the confocal optical height position detection unit and the other detected by the interferometric height position detection unit. The controller controls the condensing point position adjustment unit based on the height position obtained by correcting the height position of the upper face of the workpiece detected by the interferometric height position detection unit using the correction value.

Abstract: A laser processing apparatus includes a beam splitting unit disposed between a pulsed laser beam oscillating unit and a condenser. The beam splitting unit includes a half-wave plate that rotates the plane of polarization of a pulsed laser beam, a birefringent lens that splits the pulsed laser beam that has passed through the half-wave plate into ordinary light and extraordinary light, the birefringent lens being formed by joining two kinds of crystalline bodies to each other across a curved plane of a concave surface and a convex surface, and a splitting angle adjusting unit that moves the birefringent lens in a direction orthogonal to the pulsed laser beam that has passed through the half-wave plate to change the angle of incidence with respect to the curved plane and adjust a beam splitting angle.

Abstract: A laser machining apparatus that includes an interferometric height position detection unit, a condensing point position adjustment unit, and a confocal optical height position detection unit. A controller of the laser machining apparatus specifies, as a correction value, the difference between the two height positions of the upper face of the workpiece, one detected by the confocal optical height position detection unit and the other detected by the interferometric height position detection unit. The controller controls the condensing point position adjustment unit based on the height position obtained by correcting the height position of the upper face of the workpiece detected by the interferometric height position detection unit using the correction value.

Abstract: A laser beam having an annular spot shape with which a workpiece is irradiated is reflected on an upper surface and a lower surface of the workpiece. The reflected light having the annular spot shape which is reflected on the lower surface of the workpiece is intercepted by a pinhole mask, whereas the reflected light having the annular spot shape which is reflected on the upper surface of the workpiece is permitted to pass through the pinhole mask, and the intensity of light received is detected based on the latter reflected light. Therefore, the height position of the upper surface of a workpiece can be detected even where the workpiece is transmissive to visible rays. In this case, with regard to the reflected light having the annular spot shape which is reflected on the upper surface of the workpiece, the intensity of the light after diffusion by a laser beam diffusing unit is detected by a photodetector having a detecting surface with a predetermined area.

Abstract: A laser processing apparatus including a detecting unit. The detecting unit includes a white light source for emitting white light, a focusing lens for focusing the white light to the workpiece, a first optical fiber for guiding the white light emitted from the white light source to the focusing lens, a detector for detecting the intensity of reflected light from the workpiece, and a second optical fiber for guiding the reflected light to the detector. Accordingly, the white light to be focused to the workpiece can be easily handled and only a wavelength component focused on the workpiece can be stably propagated.