The invention is directed to a double-disc grinding apparatus including: a rotatable ring holder configured to support a sheet workpiece along a circumferential direction from an outer circumference side of the workpiece; a pair of grinding wheels for grinding surfaces of the workpiece supported by the ring holder; and a hydrostatic bearing for supporting the ring holder without contact from both of a direction of a rotational axis of the ring holder and a direction perpendicular to the rotational axis by hydrostatic pressure of fluid supplied from both directions, wherein supply pressures at which the fluid is supplied from the direction of the rotational axis and from the direction perpendicular to the rotational axis can be independently controlled. The invention provides a double-disc grinding apparatus and a workpiece double-disc grinding method that can improve variation in nanotopography depending on the lot of workpieces or grinding wheels to obtain nanotopography stably.

A manufacturing method of a carrier for a double-side polishing apparatus by performing a lapping process on the carrier for a double-side polishing apparatus, being gear shaped and having a holding hole to hold a semiconductor wafer; including: providing an outer carrier, being larger than the carrier for a double-side polishing apparatus in size, having a hole to hold the carrier for a double-side polishing apparatus, and being configured to arrange the center of the hole to be eccentric to the center of the outer carrier; holding the carrier for a double-side polishing apparatus by the outer carrier, with the carrier for a double-side polishing apparatus being put in the hole; and performing a lapping process on the carrier for a double-side polishing apparatus with the center of the hole being eccentric to the center of the outer carrier.

A manufacturing method of a carrier for a double-side polishing apparatus by performing a lapping process on the carrier for a double-side polishing apparatus, being gear shaped and having a holding hole to hold a semiconductor wafer; including: providing an outer carrier, being larger than the carrier for a double-side polishing apparatus in size, having a hole to hold the carrier for a double-side polishing apparatus, and being configured to arrange the center of the hole to be eccentric to the center of the outer carrier; holding the carrier for a double-side polishing apparatus by the outer carrier, with the carrier for a double-side polishing apparatus being put in the hole; and performing a lapping process on the carrier for a double-side polishing apparatus with the center of the hole being eccentric to the center of the outer carrier.

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.

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.

A wafer double-side polishing apparatus is disclosed. The wafer double-side polishing apparatus includes an upper plate and a lower plate facing each other, polishing pads respectively disposed at a lower portion of the upper plate and at an upper portion of the lower plate, a first gear disposed in a central region of an upper surface of the lower plate, a second gear disposed in a peripheral region of the upper surface of the lower plate, and carriers disposed between the polishing pads while being engaged between the first gear and the second gear. The upper plate includes a plurality of slurry supply holes extending in a vertical direction. Each of the carriers includes at least one wafer accommodation hole. The sum of cross-sectional areas of the wafer accommodation holes of the carriers is 32 to 34% of the cross-sectional area of the lower plate.

A wafer double-side polishing apparatus is disclosed. The wafer double-side polishing apparatus includes an upper plate and a lower plate facing each other, polishing pads respectively disposed at a lower portion of the upper plate and at an upper portion of the lower plate, a first gear disposed in a central region of an upper surface of the lower plate, a second gear disposed in a peripheral region of the upper surface of the lower plate, and carriers disposed between the polishing pads while being engaged between the first gear and the second gear. The upper plate includes a plurality of slurry supply holes extending in a vertical direction. Each of the carriers includes at least one wafer accommodation hole. The sum of cross-sectional areas of the wafer accommodation holes of the carriers is 32 to 34% of the cross-sectional area of the lower plate.

Disclosed is a wafer processing apparatus. The wafer processing apparatus includes a first surface plate on which a plurality of carriers is arranged, a first gear arranged at the central region of the first surface plate and engaged with the plurality of carriers, a second gear arranged around the edge region of the first surface plate and engaged with the plurality of carriers, a motor rotating the first surface plate in a first direction, a fixing hanger arranged opposite the first surface plate, and a second surface plate hung on the fixing hanger such that a clearance between the first surface plate and the second surface plate may be varied.

Disclosed is a wafer processing apparatus. The wafer processing apparatus includes a first surface plate on which a plurality of carriers is arranged, a first gear arranged at the central region of the first surface plate and engaged with the plurality of carriers, a second gear arranged around the edge region of the first surface plate and engaged with the plurality of carriers, a motor rotating the first surface plate in a first direction, a fixing hanger arranged opposite the first surface plate, and a second surface plate hung on the fixing hanger such that a clearance between the first surface plate and the second surface plate may be varied.

A polishing apparatus includes a chuck table configured to hold the workpiece, a polishing unit including a rotatable polishing pad configured to polish the workpiece held by the chuck table, a moving mechanism configured to move a holding unit to a loading and unloading region for loading and unloading the workpiece onto and from the chuck table and a polishing region for polishing the workpiece by the polishing unit, a raising and lowering mechanism configured to bring the polishing pad into contact with the workpiece held by the chuck table or separate the polishing pad from the workpiece by raising or lowering the polishing unit, and a shaping unit configured to shape the polishing pad. The shaping unit comes into contact with a polishing surface of the polishing pad, and shapes the polishing surface into a desired shape.