Abstract: A processing method for processing an SiC ingot includes a peel-off zone forming step of applying a processing pulsed laser beam having a wavelength transmittable through the ingot to the ingot while positioning a focused spot of the processing pulsed laser beam at a depth corresponding to a thickness of a wafer to be peeled off from the ingot, to form belt-shaped peel-off zones each including cracks in the ingot, a reflected beam detecting step of applying an inspecting laser beam having a wavelength transmittable through the ingot and reflectable from cracks of the peel-off zones and detecting an intensity of a beam reflected by the cracks, and a processing laser beam output power adjusting step of adjusting an output power of the processing pulsed laser beam to keep the intensity of the reflected beam detected in the reflected beam detecting step within a predetermined range.

Abstract: A SiC wafer is produced from a single crystal SiC ingot. Wafer producing apparatus includes a holding unit for holding the ingot, a flattening unit for grinding the upper surface of the ingot, thereby flattening the upper surface, a laser applying unit for setting the focal point of a laser beam having a transmission wavelength to the ingot inside the ingot at a predetermined depth from the upper surface of the ingot, the predetermined depth corresponding to the thickness of the wafer to be produced, and next applying the laser beam to the ingot to thereby form a separation layer for separating the wafer from the ingot, a wafer separating unit for holding the upper surface of the ingot to separate the wafer from the ingot along the separation layer, and a wafer storing unit for storing the wafer separated from the ingot.

Abstract: A diamond substrate producing method includes a belt-shaped separation layer forming step of applying a laser beam to a diamond ingot as relatively moving the ingot and a focal point of the laser beam in a [110]-direction perpendicular to a (110)-plane, thereby forming a belt-shaped separation layer extending in the [110]-direction inside the ingot, an indexing step of relatively moving the ingot and the focal point in an indexing direction parallel to a (001)-plane and perpendicular to the [110]-direction, a planar separation layer forming step of repeating the belt-shaped separation layer forming step and the indexing step to thereby form a planar separation layer parallel to the (001)-plane inside the ingot, the planar separation layer being composed of a plurality of belt-shaped separation layers arranged side by side in the indexing direction, and a separating step of separating a substrate from the diamond ingot along the planar separation layer.

Abstract: A wafer producing apparatus for producing an SiC wafer from a single-crystal SiC ingot includes an ingot grinding unit, a laser applying unit that applies a pulsed laser beam having a wavelength that is transmittable through the single-crystal SiC ingot while positioning a focal point of the pulsed laser beam in the single-crystal SiC ingot at a depth corresponding to the thickness of the SiC wafer to be produced from an upper surface of the single-crystal SiC ingot, thereby forming a peel-off layer in the single-crystal SiC ingot, a wafer peeling unit that peels the SiC wafer off the peel-off layer in the single-crystal SiC ingot, and a delivery unit assembly that delivers the single-crystal SiC ingot between the ingot grinding unit, the laser applying unit, and the wafer peeling unit.

Abstract: A pressure vessel, comprising: a vessel body having a rectangular parallelepiped shape for containing high pressure gas; a dividing wall in the form of a plate and disposed in the vessel body; and a plurality of ribs disposed on an outer surface of the vessel body. The vessel body includes: a top wall having a rectangular shape; a bottom wall having a rectangular shape and facing the top wall; and a surrounding wall joining a peripheral edge of the top wall and a peripheral edge of the bottom wall. The dividing wall is disposed in the vessel body to define a first chamber having a rectangular parallelepiped shape and a second chamber having a rectangular parallelepiped shape in cooperation with the vessel body. Each of the plurality of ribs extends over an entire circumference of the vessel body and along a plane perpendicularly intersecting the dividing wall.

Abstract: A controller performs, in a first mode, a first operation for controlling composite electromagnetic force of electromagnets such that a target member moves within a predetermined moving range, and a second operation for acquiring temperature drift correlation information indicative of a correlation between a reference value and an input-output characteristic of a position sensor, based on the reference value and the input-output characteristic of the position sensor in the first operation. The controller performs, in a second mode, a third operation for controlling the composite electromagnetic force of the electromagnets according to a signal level of a detection signal from the position sensor, and a fourth operation for compensating the input-output characteristic of the position sensor in the third operation, based on the temperature drift correlation information and the reference value in the third operation.

Abstract: A SiC wafer is produced from a single crystal SiC ingot. A modified layer is formed by setting a focal point of a pulsed laser beam inside the ingot at a predetermined depth from the upper surface of the ingot, the predetermined depth corresponding to the thickness of the wafer to be produced. The pulsed laser beam is applied to the ingot while moving the ingot in a first direction perpendicular to a second direction where an off angle is formed, thereby forming a modified layer in the first direction inside the ingot and cracks propagating from the modified layer along a c-plane. A separation surface is formed by indexing the ingot in the second direction and applying the laser beam plural times to thereby form a separation surface inside the ingot. Part of the ingot is separated along the separation surface to thereby produce the wafer.

Abstract: A SiC wafer is produced from a single crystal SiC ingot. A focal point of a pulsed laser beam having a transmission wavelength to the ingot is set inside the ingot at a predetermined depth from a flat surface of the ingot, the predetermined depth corresponding to the thickness of the wafer to be produced. The pulsed laser beam is applied to the ingot to thereby form a separation layer for separating the wafer from the ingot. The wafer is separated from the ingot along the separation layer, and a flat surface is formed by grinding an upper surface of the ingot as a rough separation surface left after separating the wafer, thereby removing the roughness of the upper surface of the ingot to flatten the upper surface of the ingot.

Abstract: A laser processing apparatus for producing a GaN wafer from a GaN ingot includes a laser beam irradiating unit configured to apply a laser beam having a wavelength capable of passing through the GaN ingot held by a chuck table. The laser beam irradiating unit includes a laser oscillator configured to oscillate the laser beam. The laser oscillator includes a seeder configured to oscillate a high-frequency pulsed laser, a thinning-out unit configured to thin out high-frequency pulses oscillated by the seeder at a predetermined repetition frequency, and generate one burst pulse with a plurality of high-frequency pulses as sub-pulses, and an amplifier configured to amplify the generated burst pulse.

Abstract: A semiconductor substrate processing method includes: a peeling layer forming step of forming a peeling layer by irradiating a first semiconductor substrate with a laser beam having a wavelength capable of passing through the first semiconductor substrate while positioning a focal point of the laser beam within the first semiconductor substrate; a second semiconductor substrate forming step of forming a second semiconductor substrate by epitaxial growth on an upper surface of the first semiconductor substrate after performing the peeling layer forming step; a peeling step of peeling off the first semiconductor substrate from the peeling layer; and a grinding step of grinding and removing the first semiconductor substrate after performing the peeling step.

Abstract: Disclosed herein is an SiC wafer producing method for producing an SiC wafer from a single crystal SiC ingot. The SiC wafer producing method includes a wafer producing step of separating a part of the ingot along a separation layer as an interface. The wafer producing step includes the steps of immersing the ingot in a liquid and applying the ultrasonic wave from an ultrasonic vibrator through the liquid to the ingot, the ultrasonic wave having a frequency greater than or equal to a critical frequency close to the natural frequency of the ingot.

Abstract: A method for producing a wafer from a hexagonal single crystal ingot includes: planarizing an upper surface of the hexagonal single crystal ingot; applying a laser beam of such a wavelength as to be transmitted through the ingot, with a focal point positioned in an inside of a region not to be formed with devices of a wafer to be produced from the upper surface of the ingot which has been planarized, to form a production history; and applying a laser beam of such a wavelength as to be transmitted through the hexagonal single crystal ingot with a focal point of the laser beam positioned at a depth corresponding to a thickness of the wafer to be produced from the upper surface of the hexagonal single crystal ingot which has been planarized, to form an exfoliation layer.

Abstract: Disclosed herein is a laser processing apparatus for forming a separation layer inside an ingot by applying a laser beam to an end surface of the ingot in the condition where the focal point of the laser beam is set inside the ingot, the laser beam having a transmission wavelength to the ingot. The laser processing apparatus includes a holding unit for holding the ingot, a moving unit for moving the holding unit in a direction parallel to the end surface of the ingot held by the holding unit, a laser beam applying unit for applying the laser beam to the ingot held by the holding unit, an imaging unit for detecting the position of the ingot in the direction parallel to the end surface of the ingot, and a height detecting unit for detecting the height of the end surface of the ingot held by the holding unit.

Abstract: A wafer production method for producing a wafer from a lithium tantalate ingot includes a step of irradiating, from an end face of a lithium tantalate ingot which is a 42-degree rotation Y cut ingot having an orientation flat formed in parallel to a Y axis, a laser beam of a wavelength having transparency to lithium tantalate with a focal point of the laser beam positioned in the inside of the ingot to form a modified layer in the inside of the ingot while the ingot is fed for processing, and a step of applying external force to the ingot to peel off a plate-shaped material from the ingot to produce a wafer. At the step of forming a modified layer, the ingot is relatively fed for processing in a direction parallel or perpendicular to the orientation flat.

Abstract: A method for producing a wafer from a hexagonal single crystal ingot includes: planarizing an upper surface of the hexagonal single crystal ingot; applying a laser beam of such a wavelength as to be transmitted through the ingot, with a focal point positioned in an inside of a region not to be formed with devices of a wafer to be produced from the upper surface of the ingot which has been planarized, to form a production history; and applying a laser beam of such a wavelength as to be transmitted through the hexagonal single crystal ingot with a focal point of the laser beam positioned at a depth corresponding to a thickness of the wafer to be produced from the upper surface of the hexagonal single crystal ingot which has been planarized, to form an exfoliation layer.

Abstract: A planarization method includes a grinding step of holding the opposite side to a separation surface in an SiC ingot by a rotatable chuck table and rotating a grinding wheel having plural grinding abrasives disposed in a ring manner to grind the separation surface of the SiC ingot held by the chuck table, and a flatness detection step of irradiating the separation surface of the SiC ingot exposed from the grinding wheel with light and detecting reflected light to detect the degree of flatness. The grinding step is ended when that the separation surface of the SiC ingot has become flat is detected in the flatness detection step.

Abstract: A shaft seal device is fixed to a container that separates a high-pressure fluid and a low-pressure fluid from each other, and seals a shaft-penetrated portion of the container through which a rotational shaft extends. This shaft seal device includes: a seal casing having a through-hole through which the rotational shaft extends, the seal casing having a seal chamber which communicates with the through-hole and into which the high-pressure fluid flows; and a disk-shaped seal body which is housed in the seal chamber, the seal body being rotatable together with the rotational shaft and having an annular surface perpendicular to an axis of the rotational shaft. An inner surface of the seal casing, which faces the annular surface of the seal body and defines the seal chamber, is a flat surface perpendicular to the axis of the rotational shaft.

Abstract: A method of detecting a Facet region includes: a fluorescence luminance detecting step of detecting fluorescence luminance unique to SiC by irradiating a SiC ingot with exciting light having a predetermined wavelength from a top surface of the SiC ingot; and a coordinate setting step of setting a region in which the fluorescence luminance is equal to or higher than a predetermined value in the fluorescence luminance detecting step as a non-Facet region, setting a region in which the fluorescence luminance is lower than the predetermined value in the fluorescence luminance detecting step as a Facet region, and setting coordinates of a boundary between the Facet region and the non-Facet region.

Abstract: A hexagonal single crystal wafer is produced from a hexagonal single crystal ingot. A wafer producing method includes a separation start point forming step of applying a laser beam to the ingot to form a modified layer parallel to the upper surface of the ingot and cracks extending from the modified layer, thus forming a separation start point. The focal point of the laser beam is relatively moved in a first direction perpendicular to a second direction where a c-axis in the ingot is inclined by an off angle with respect to a normal to the upper surface. The off angle is formed between the upper surface and a c-plane perpendicular to the c-axis, thereby linearly forming the modified layer extending in the first direction. The laser beam is applied to the ingot with the direction of the polarization plane of the laser beam set to the first direction.

Abstract: A wafer producing method for producing a hexagonal single crystal wafer from a hexagonal single crystal ingot, including a separation start point forming step of setting the focal point of a laser beam inside the ingot at a predetermined depth from the ingot's upper surface, which depth corresponds to the thickness of the wafer to be produced, and next applying the laser beam while relatively moving the focal point and the ingot to thereby form: (i) a modified layer parallel to the ingot's upper surface, and (ii) cracks extending from the modified layer, thus forming a separation start point. The laser beam is applied to form the modified layer in a condition where the relation of ?0.3?(d?x)/d?0.5 holds, where d is the diameter of a focused spot of the laser beam and x is the spacing between adjacent focused spots of the laser beam.