A wire saw apparatus 1 executes cut-machining by pressing a workpiece W against a cutting wire 3 spirally wound around multiple wire guides 2, while running the cutting wire 3 and simultaneously swinging the wire guides 2 as well as the cutting wire 3. The wire saw apparatus 1 includes a controller 8 controlling a position of a workpiece holder 51 for holding the workpiece W. The position is controlled depending on a swing angle of the cutting wire 3 so that machined portion of the workpiece W is shaped into an arc.

A plate crystal cut from a gallium nitride crystal with a crystal cutting wire, where the plate crystal has a principal face of (2021), and a magnitude of warpage of the plate crystal is 1.0 m/mm or less in a line along the perpendicular projection of the c axis on the principal face passing through the center of the principal face.

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.

Cutting fluids for brittle materials, e.g., silicon ingot, comprise, in weight percent: A. 70-99% polyalkylene glycol (PAG), e.g., polyethylene glycol; B. 0.01-10% PAG-grafted polycarboxylate; and C. 0-30% water.
These cutting fluids are used with abrasive materials, e.g., silicon carbide (SiC), to form cutting slurries. The slurry is sprayed on the cutting tool, e.g., a wire saw, to cut a brittle work piece, e.g., a silicon ingot.

In a wafer processing method by which, by using, as a reference surface, a flat surface obtained by applying a curable material to the whole of one surface of a wafer obtained by slicing a semiconductor single-crystal ingot by using a wire saw apparatus, surface grinding is performed on the other surface of the wafer and surface grinding is performed on the one surface of the wafer by using the other surface of the wafer subjected to surface grinding as a reference surface, both surfaces of the wafer are planarized at the same time immediately after the wafer is obtained by slicing.

An abrasive article comprising an elongated body, a bonding layer overlying a surface of the elongated body, and abrasive grains contained within the bonding layer at an average abrasive grain concentration within a range between about 0.02 ct/m and about 0.30 ct/m.

A method for slicing an ingot, including: forming a wire row by a wire spirally wound between a plurality of wire guides and configured to travel in an axial direction; and pressing an ingot against the wire row while supplying a contact portion between the ingot and the wire with a slurry from a nozzle, thereby slicing the ingot into wafers. The slurry is supplied such that slurries whose temperatures are separately controlled by two or more lines of heat exchangers are respectively supplied from two or more sections of the nozzle which are orthogonal to a travelling direction of the wire row. Consequently, a wire saw and a method for slicing an ingot are provided which enable separate control of wafer shapes depending on ingot-slicing positions.

An abrasive article including a substrate having an elongated body, a tacking layer overlying the substrate, and a first type of abrasive particle overlying the tacking layer and defining a first abrasive particle concentration at least about 10 particles per mm of substrate.

A method for slicing a workpiece into wafers by imparting axial reciprocating motion to a wire wound around a plurality of grooved rollers, and moving the workpiece relatively downwardly to press the workpiece against the reciprocating wire and feed the workpiece with the workpiece cut into while supplying a slurry to the wire, the method including the steps of: configuring each of the grooved rollers such that a distance from a bottom of grooves of the grooved roller to a rotating shaft of the grooved roller decreases gradually from a wire-supply side toward a wire-collection side; slicing the workpiece in such a manner that the workpiece is pressed against the wire on the wire-supply side before the workpiece is pressed against the wire on the wire-collection side.

A method of shaping a laminated glass structure includes providing the laminated glass structure comprising a flexible glass sheet having a thickness of no greater than about 0.3 mm laminated to a non-glass substrate by an adhesive layer. The flexible glass structure and adhesive layer are ground using a first tool to remove glass material. The non-glass substrate is cut with a second tool different from the first tool through a kerf formed through the flexible glass structure thereby forming a shaped laminated glass structure. A glass edge strength of a cut edge of the shaped laminated glass structure is at least about 20 MPa.