A workpiece support jig includes a support plate supporting a workpiece on a first surface while covering a support surface of a chuck table with a second surface opposite to the first surface and a retainer plate including an area sufficient to cover the whole of the workpiece and sandwiching the workpiece, held on the first surface of the support plate, between the support plate and itself. The support plate includes a plurality of groove parts corresponding to projected division lines of the supported workpiece and a plurality of through holes formed in chip-holding regions demarcated and divided by the intersecting groove parts. When the workpiece divided by a processing unit into chips is unloaded from the chuck table, the workpiece is unloaded while being sandwiched between the support plate and the retainer plate.

A wafer is divided into device chips each of which is surrounded by a mold resin. The wafer has a plurality of devices arranged like a matrix with a spacing having a predetermined width, the front side of each device being covered with the mold resin, the spacing being filled with the mold resin to form a street between any adjacent ones of the devices. The wafer processing method includes a division start point forming step of forming a division start point along each street at the lateral center of the mold resin filling the spacing and a dividing step of applying an external force to the wafer after performing the division start point forming step, thereby laterally dividing each street into two parts at the division start point to obtain the device chips divided from each other, each device chip being surrounded by the mold resin.

A dividing method for a disk-shaped workpiece having a plurality of first division lines and a plurality of second division lines intersecting the first division lines. The workpiece is cut along the first and second division lines by using a cutting blade in a down cut manner as supplying a cutting fluid to the cutting blade, wherein the workpiece is fully cut in a thickness direction thereof to obtain a plurality of chips. The dividing method includes a first cutting step of cutting the workpiece along the first division lines and a second cutting step of cutting the workpiece along the second division lines. In at least the second cutting step, the outer circumference of the workpiece at the cut end of each second division line is not cut to form an uncut region, thereby suppressing the formation of waste chips.

Herein is provided a method of milling a brittle workpiece (46) using a milling tool (10), the workpiece (46) comprising a material, the material having a Ductile-Brittle Transition Undeformed Chip Thickness, DBh.sub.rn, the milling tool (10) comprising a tool shank (12) having an axis of rotation (14), and further comprising a tool head (16) comprising superhard material at one end thereof, the tool head (16) having a diameter (42), and operating the milling tool (10) such that an Undeformed Chip Thickness, h.sub.m, of the workpiece (46) is less than said Ductile-Brittle Transition Undeformed Chip Thickness, DBh.sub.m of the material.

Herein is provided a method of milling a brittle workpiece (46) using a milling tool (10), the workpiece (46) comprising a material, the material having a Ductile-Brittle Transition Undeformed Chip Thickness, DBh.sub.rn, the milling tool (10) comprising a tool shank (12) having an axis of rotation (14), and further comprising a tool head (16) comprising superhard material at one end thereof, the tool head (16) having a diameter (42), and operating the milling tool (10) such that an Undeformed Chip Thickness, h.sub.m, of the workpiece (46) is less than said Ductile-Brittle Transition Undeformed Chip Thickness, DBh.sub.m of the material.

A method is for dividing a plate-like workpiece in which devices are respectively formed in regions sectioned by a plurality of intersecting planned dividing lines. The method includes: forming a first cutting groove not reaching a rear surface of a workpiece by causing a rotating cutting blade to cut into from a front surface of the workpiece along the planned dividing lines; after forming the first cutting groove, forming a second cutting groove not reaching a bottom portion of the first cutting groove by causing the rotating cutting blade to cut into from the rear surface of the workpiece along the first cutting groove; and after forming the second cutting groove, dividing the workpiece along the planned dividing lines by applying external force to the workpiece.

A semiconductor substrate manufacturing method includes: epitaxially growing a columnar III nitride semiconductor single crystal on a principal place of a circular substrate; removing a hollow cylindrical region at an outer peripheral edge side of the III nitride semiconductor single crystal to leave a solid columnar region at an inside of the hollow cylindrical region of the III nitride semiconductor single crystal; and slicing the solid columnar region after removing the hollow cylindrical region. The hollow cylindrical region is removed such that the shape of the III nitride semiconductor single crystal is always keeps an axial symmetry that a center axis of the III nitride semiconductor single crystal is defined as a symmetric axis.

The fancy concave cutting gemstone faceting attachment device is a device that allows concave type faceting of gemstones by means of mounting this device to an existing faceting machine. This may be accomplished utilizing the existing machines drive motors and hardware. This device prevents the need to purchase completely separate concave faceting machines to accomplish the same task of concave faceting. This is preferably a universal machine design allowing this device to mount to many makes of faceting machines in the current marketplace.

A spindle apparatus may include a cover; a rotation body within the cover to be rotatable about a central axis thereof and including a first end portion exposed to the outside and a second end portion opposite to the first end portion; a cutting tool on the first end portion of the rotation body; and an electrostatic discharge (ESD) prevention device on the second end portion of the rotation body. The ESD prevention device includes a charge discharge structure in at least partial contact with the second end portion of the rotation body to discharge charges accumulated in the cutting tool to the outside; a sensor above the charge discharge structure to detect whether the charge discharge structure is in contact with the rotation body; and a driver to move the charge discharge structure so that the charge discharge structure is in contact with the rotation body.