An object is to provide a SiC wafer in which a detection rate of an optical sensor can improved and a SiC wafer manufacturing method. The method includes: a satin finishing process S141 of satin-finishing at least a back surface 22 of a SiC wafer 20; an etching process 21 of etching at least the back surface 22 of the SiC wafer 20 by heating under Si vapor pressure after the satin finishing process S141; and a mirror surface processing process S31 of mirror-processing a main surface 21 of the SiC wafer 20 after the etching process S21. Accordingly, it is possible to obtain a SiC wafer having the mirror-finished main surface 21 and the satin-finished back surface 22.

A wire saw apparatus including: a wire row formed of a wire wound around a plurality of wire guides and reciprocatively travels in an axial direction; a nozzle from a coolant or slurry is supplied to the wire; and a workpiece feed mechanism presses a held workpiece against the wire row, the wire saw apparatus slice the workpiece into a wafer shape by pressing the workpiece held by the workpiece feed mechanism against the wire row and feeding it for slicing while supplying the coolant or the slurry from the nozzle to the wire, the wire saw apparatus nozzle is arranged above the wire row to be orthogonal to the wire row, and windbreak plates are arranged on both left and right sides of the arranged nozzle seen from an axial direction.

An amount of warp of a wafer is not only reduced, but the amount of warp of the wafer is also accurately controlled to a desired amount. The present invention relates to a method for slicing a semiconductor single crystal ingot, by which a cylindrical semiconductor single crystal ingot is bonded to and held by a holder in a state where the ingot is rotated at a predetermined rotation angle around a crystal axis of the ingot different from a center axis of a cylinder of this ingot and the ingot is sliced by a cutting apparatus in this state. The predetermined rotation angle at the time of bonding and holding the ingot with the use of the holder in such a manner that an amount of warp of a wafer sliced out by the cutting apparatus becomes a predetermined amount.

A method for cutting a monocrystalline silicon square rod may include the steps of: loading: providing a square rod on a working platform and clamping the square rod, and lowering the square rod until it comes into contact with a diamond wire; cutting: setting cutting parameters, and cutting the square rod by forward and reverse reciprocating movement along the diamond wire, wherein during cutting process, first speed of the working platform varies synchronously with wire speed; and unloading: unloading after the cutting step is finished, wherein the square rod is gradually separated from the diamond wire.

An abrasive article including a substrate having an elongated body, a tacking layer overlying the substrate, a first type of abrasive particle overlying the tacking layer, a second type of abrasive particle different than the first type of abrasive particles overlying the tacking layer, and a bonding layer overlying at least a portion of one of the first type of abrasive particle and the second type of abrasive particle and the tacking layer.

An abrasive article including a substrate having an elongated body, a tacking layer overlying the substrate, a first type of abrasive particle overlying the tacking layer, a second type of abrasive particle different than the first type of abrasive particles overlying the tacking layer, and a bonding layer overlying at least a portion of one of the first type of abrasive particle and the second type of abrasive particle and the tacking layer.

A method of producing wafers or discs from an industrially grown crystal includes: scanning a crystal in volume and forming a 3D volumetric digital model of the crystal, recording 3D spatial coordinates of defects detected during said scanning, measuring one or more crystal axes provided by a crystalline structure of the crystal, and recording this crystal axis in said 3D model of the crystal, coring out one or more cores from the crystal in a selected crystal direction which is parallel to one of said crystal axes or at a defined angle with respect to said crystal axis, and slicing the core orthogonally to the selected crystal direction with a wafer slicing machine comprising a slicing tool comprising a plurality of cutting wires or blades spaced at a regular slicing pitch configured to cut wafers of identical thicknesses from the core.

An apparatus configured to automatically set a stroke range of a cutting device includes: a driver including a rotary shaft on which a bobbin is detachably mounted; a traverse configured to move an attachment point of a wire with respect to the bobbin; and a sensor configured to measure a distance between the driver and the bobbin. The apparatus further includes a controller configured to adjust the stroke range of the traverse to move in parallel based on the distance measured by the sensor. The sensor is configured to measure, as first distance data, a distance between a side of the driver and a side of the bobbin.

A cutting method for cutting a workpiece is provided. This cutting method includes holding the workpiece including a crystal structure having a c-axis inclined with respect to a perpendicular to a surface and a c-plane perpendicular to the c-axis and cutting the workpiece along a planned cutting plane that is perpendicular to the surface and is inclined with respect to the c-plane by rotating a cutting blade having an annular cutting edge and making a tip portion of the cutting edge cut into the workpiece. In the cutting the workpiece, the tip portion is made to cut into the workpiece in a state in which a force in such an orientation as to bring an angle formed by the planned cutting plane and the tip portion close to 0 acts on the cutting edge from the workpiece when the tip portion is made to cut into the workpiece.