A method for processing semiconductor wafers includes obtaining measurement data of an edge profile of a semiconductor wafer processed by a front-end process tool. The method includes determining an edge profile center point based on the measurement data, generating a raw height profile, and generating an ideal edge profile. The method further includes generating a Gapi edge profile of the semiconductor wafer based on the raw height profile and the ideal edge profile and calculating a Gapi edge value of the semiconductor wafer based on the Gapi edge profile. The generated Gapi edge profile and/or the calculated Gapi edge value may be used to tune the front-end process tool and/or sort the semiconductor wafer for polishing. Systems include at least a front-end process tool, a flatness measurement tool, and a computing device.

A modular apparatus (10) for machining flat sheets, in particular glass, plate glass, or mirror sheets or sheets made from stone materials or the like, comprising machining moduli consisting of a first store (16) suitable for receiving sheets to be machined (25) and a second store (18) suitable for receiving machined sheets (27), a first grinding machine (12), and a second grinding machine (14) suitable for performing grinding machinings along the peripheral edges of said sheets (25), one or more further moduli for machining said flat sheets, if any, of the corner cutting, drill, or washing machine types, possibly associated with said first and second grinding machines (12, 14), and interface means for transferring said flat sheets between said machining moduli.

A modular apparatus (10) for machining flat sheets, in particular glass, plate glass, or mirror sheets or sheets made from stone materials or the like, comprising machining moduli consisting of a first store (16) suitable for receiving sheets to be machined (25) and a second store (18) suitable for receiving machined sheets (27), a first grinding machine (12), and a second grinding machine (14) suitable for performing grinding machinings along the peripheral edges of said sheets (25), one or more further moduli for machining said flat sheets, if any, of the corner cutting, drill, or washing machine types, possibly associated with said first and second grinding machines (12, 14), and interface means for transferring said flat sheets between said machining moduli.

A wafer edge polishing apparatus includes a cleaning mechanism exhibiting a superb effect of cleaning slurry residue adhered on a chuck table. This edge polishing device is provided with: a chuck table which sucks/holds a wafer; a rotation drive mechanism which rotates the chuck table; an edge polishing unit which polishes an edge of the wafer while supplying slurry to the wafer, which is rotating while being sucked/held by the chuck table; and a cleaning unit which removes slurry residue on the chuck table. The cleaning unit includes a cleaning head, and cleans the chuck table through high-pressure cleaning and brush-cleaning by using the cleaning head, wherein the cleaning head is provided with a high-pressure jet nozzle and a brush surrounding the periphery of the high-pressure jet nozzle.

Provided are a method of polishing a silicon wafer and a method of producing a silicon wafer which can reduce the formation of step-forming microdefects on a silicon wafer. The method includes: a double-side polishing step of performing polishing on front and back surfaces of a silicon wafer; a notch portion polishing step of performing polishing on a beveled portion of a notch portion of the silicon wafer after the double-side polishing step; a peripheral beveled portion polishing step of performing polishing on the beveled portion on the periphery of the silicon wafer other than the beveled portion of the notch portion after the notch portion polishing step; and a finish polishing step of performing finish polishing on the front surface of the silicon wafer after the peripheral beveled portion polishing step. The notch portion polishing step is performed in a state where the front surface is wet with water.

A polishing apparatus for an outer peripheral portion of a wafer includes: a stage for horizontally holding a disc-shaped wafer; a rotation drive unit for rotating the stage around its center axis as a rotation axis; polishing heads having an inner circumferential surface mounted with polishing pads; and a polishing-head drive mechanism for bringing the polishing pads into contact with the outer peripheral portion of the wafer and sliding the polishing heads in a direction slanted relative to a center axis of the wafer or a vertical direction thereof under application of a predetermined polishing pressure to the outer peripheral portion of the wafer. The inner circumferential surface of each of the polishing heads is mounted with two or more types of the polishing pads having different physical property values in the vertical direction.

A polishing apparatus capable of forming a step-shaped recess having a right-angled cross section in an edge portion of a substrate, such as a wafer, is disclosed. The polishing apparatus includes: a substrate rotating device configured to rotate the substrate about a rotation axis; a first roller having a first circumferential surface configured to press a polishing tape against the edge portion of the substrate; and a second roller having a second circumferential surface in contact with the first circumferential surface. The second roller has a tape stopper surface that restricts movement of the polishing tape in a direction away from the rotation axis. The tape stopper surface is located radially outward of the first circumferential surface.

A method evaluates an edge shape of a silicon wafer, in which as shape parameters in a wafer cross section, when defining a radial direction reference L1, a radial direction reference L2, an intersection point P1, a height reference plane L3, h1 [μm], h2 [μm], a point Px3, a straight line Lx, an angle θx, a point Px0, δ [μm], a point Px1, and a radius Rx [μm], the edge shape of the silicon wafer is measured, values of the shape parameters h1, h2, and δ are set, the shape parameters Rx and θx are calculated in accordance with the definition based on measurement data of the edge shape, and the edge shape of the silicon wafer is determined from the calculated Rx and θx to be evaluated. Consequently, a method evaluates an edge shape of a silicon wafer capable of preventing an occurrence of trouble.

A polishing method for polishing a wafer by use of a polishing unit having a spindle with a polishing tool, the polishing tool having a disk-shaped base and an annular polishing layer that is fixed to one surface of the base and that includes an opening being located at a central portion in a diameter direction of the base and having a predetermined diameter, a maximum width of an effective polishing region of the polishing layer in a radial direction of the base being smaller than the radius of the wafer and the radius of the wafer being smaller than the diameter of the opening, the method includes polishing the wafer in such a manner that a part of a peripheral edge of the wafer protrudes from a periphery of the polishing layer and that the center of the wafer is located in the opening section of the polishing layer.

A method for preparing a SiC ingot includes: disposing a raw material and a SiC seed crystal facing each other in a reactor having an internal space; subliming the raw material by controlling a temperature, a pressure, and an atmosphere of the internal space; growing the SiC ingot on the seed crystal; and collecting the SiC ingot after cooling the reactor. The wafer prepared from the ingot, which is prepared from the method, generates cracks when an impact is applied to a surface of the wafer, the impact is applied by an external impact source having mechanical energy, and a minimum value of the mechanical energy is 0.194 J to 0.475 J per unit area (cm.sup.2).