A method of producing a glass article includes holding a carrier having a circular shape, in which a glass substrate having a circular shape is retained, with an upper surface plate and a lower surface plate; and polishing the glass substrate by rotating the carrier with respect to the upper surface plate and the lower surface plate, to obtain the glass article. The glass substrate is disposed in the carrier such that, in a top plan view, a center of the carrier is included in a region of the glass substrate, and a center of the glass substrate is shifted from the center of the carrier.

An inner-periphery-side cutoff part where a polishing surface of an upper plate inclines upward toward an inner periphery part of the upper plate and an inner-periphery-side cutoff part where a polishing surface of a lower plate inclines downward toward an inner periphery part of the lower plate are respectively formed on the respective inner periphery parts of the upper plate and the lower plate, or an outer-periphery-side cutoff part where the polishing surface of the upper plate inclines upward toward an outer periphery part of the upper plate and an outer-periphery-side cutoff part where the polishing surface of the lower plate inclines downward toward an outer periphery part of the lower plate are respectively formed on the respective outer periphery parts of the upper plate and the lower plate, or all of them are formed thereon.

An inner-periphery-side cutoff part where a polishing surface of an upper plate inclines upward toward an inner periphery part of the upper plate and an inner-periphery-side cutoff part where a polishing surface of a lower plate inclines downward toward an inner periphery part of the lower plate are respectively formed on the respective inner periphery parts of the upper plate and the lower plate, or an outer-periphery-side cutoff part where the polishing surface of the upper plate inclines upward toward an outer periphery part of the upper plate and an outer-periphery-side cutoff part where the polishing surface of the lower plate inclines downward toward an outer periphery part of the lower plate are respectively formed on the respective outer periphery parts of the upper plate and the lower plate, or all of them are formed thereon.

A workpiece processing apparatus including: a center drum that is rotatable around a rotation axis and has at least one first groove formed in the axial direction on the peripheral surface, a carrier having a holding hole to insert and hold a workpiece to be processed, an upper and lower turn table that are rotatable around the rotation axis in a state wherein the carrier holding workpiece is interposed, at least one hook fitted in the upper turn table's internal circumference, with the tip being inserted into the first groove and movable along first groove; wherein the center drum has at least one second groove formed in the axial direction on peripheral surface, and second groove has a length different from that of the first groove and has a supporting surface to support the hook from below at a position above a position where upper turn table processes the workpiece.

A workpiece processing apparatus including: a center drum that is rotatable around a rotation axis and has at least one first groove formed in the axial direction on the peripheral surface, a carrier having a holding hole to insert and hold a workpiece to be processed, an upper and lower turn table that are rotatable around the rotation axis in a state wherein the carrier holding workpiece is interposed, at least one hook fitted in the upper turn table's internal circumference, with the tip being inserted into the first groove and movable along first groove; wherein the center drum has at least one second groove formed in the axial direction on peripheral surface, and second groove has a length different from that of the first groove and has a supporting surface to support the hook from below at a position above a position where upper turn table processes the workpiece.

Provided is a method of lapping a semiconductor wafer, which can suppress the formation of a ring-shaped pattern in a nanotopography map. The method of lapping a semiconductor wafer includes: a stopping step of stopping lapping of a semiconductor wafer; a reversing step of reversing surfaces of the semiconductor wafer facing a upper plate and a lower plate after the stopping step; and a resuming step of resuming lapping of the semiconductor wafer after the reversing step while maintaining the reversal of the surfaces facing the plates.

Provided is a double-sided polishing method of a wafer in which the wafer, which has been set in a wafer loading hole of the carrier, is compressed and held along with the carrier with an upper platen and a lower platen and the upper platen and the lower platen are rotated while supplying slurry to the wafer. The method includes: previously measuring an inclination value of a main surface of each of a plurality of carriers in the vicinity of the edge of the wafer loading hole; selecting, from among the plurality of carriers, those for which the inclination value is equal to or smaller than a threshold based on the measurement results of the inclination value; and applying the double-sided polishing to a wafer using the selected carrier.

Provided is a double-sided polishing method of a wafer in which the wafer, which has been set in a wafer loading hole of the carrier, is compressed and held along with the carrier with an upper platen and a lower platen and the upper platen and the lower platen are rotated while supplying slurry to the wafer. The method includes: previously measuring an inclination value of a main surface of each of a plurality of carriers in the vicinity of the edge of the wafer loading hole; selecting, from among the plurality of carriers, those for which the inclination value is equal to or smaller than a threshold based on the measurement results of the inclination value; and applying the double-sided polishing to a wafer using the selected carrier.

A double-head grinding machine includes a disc-shaped carrier ring having a support hole for supporting a silicon wafer, a rotation mechanism rotating the carrier ring around a center of the carrier ring, and a grinding wheel including a grinding stone for grinding the silicon wafer. The support hole is circular and has a center eccentric to the center of the carrier ring.

A method of producing a glass article includes holding a carrier having a circular shape, in which a glass substrate having a circular shape is retained, with an upper surface plate and a lower surface plate; and polishing the glass substrate by rotating the carrier with respect to the upper surface plate and the lower surface plate, to obtain the glass article. The glass substrate is disposed in the carrier such that, in a top plan view, a center of the carrier is included in a region of the glass substrate, and a center of the glass substrate is shifted from the center of the carrier.