An apparatus for chemical mechanical polishing (CMP) of a substrate is described herein. The apparatus includes an extension disposed between a retaining ring and a chucking membrane. The extension is disposed radially outward from the edge of the substrate and is configured to contact the retaining ring during substrate processing. The extension provides a repeatable and controlled point of contact between the retaining ring and the chucking membrane. The extension may have multiple configurations, such that the contact point between the retaining ring and the chucking membrane is set at a pre-determined location or such that the contact point is moveable by an adjustable stop.

An apparatus for chemical mechanical polishing (CMP) of a substrate is described herein. The apparatus includes an extension disposed between a retaining ring and a chucking membrane. The extension is disposed radially outward from the edge of the substrate and is configured to contact the retaining ring during substrate processing. The extension provides a repeatable and controlled point of contact between the retaining ring and the chucking membrane. The extension may have multiple configurations, such that the contact point between the retaining ring and the chucking membrane is set at a pre-determined location or such that the contact point is moveable by an adjustable stop.

An elastic emission machining apparatus includes a machining element having a non-spherical shape that is configured to spin about an axis of rotation, a tank, and a driving system. The tank has a chamber positioned to receive the machining element and a slurry comprising a mixture of a liquid and chemically reactive fine particles. The driving system is coupled to and configured to engage the machining element to spin about the axis of rotation adjacent to a surface of the workpiece to accelerate the chemically reactive fine particles through a gap between the machining element and the surface of the workpiece.

An elastic emission machining apparatus includes a machining element having a non-spherical shape that is configured to spin about an axis of rotation, a tank, and a driving system. The tank has a chamber positioned to receive the machining element and a slurry comprising a mixture of a liquid and chemically reactive fine particles. The driving system is coupled to and configured to engage the machining element to spin about the axis of rotation adjacent to a surface of the workpiece to accelerate the chemically reactive fine particles through a gap between the machining element and the surface of the workpiece.

A vacuum chuck includes: a vacuum chuck stage having a circular vacuum surface; a vacuum protection pad provided to the vacuum surface; an annular or arc-shaped concave portion dividing the vacuum surface into a central region located closer to a center of the vacuum surface and an outer circumferential region located on an outer circumferential side; and radially-extending concave portions formed in the central region. The vacuum protection pad has through holes in communication with the radially-extending concave portions, and the vacuum protection pad is bonded to the vacuum surface at the central region excluding the radially-extending concave portions.

A vacuum chuck includes: a vacuum chuck stage having a circular vacuum surface; a vacuum protection pad provided to the vacuum surface; an annular or arc-shaped concave portion dividing the vacuum surface into a central region located closer to a center of the vacuum surface and an outer circumferential region located on an outer circumferential side; and radially-extending concave portions formed in the central region. The vacuum protection pad has through holes in communication with the radially-extending concave portions, and the vacuum protection pad is bonded to the vacuum surface at the central region excluding the radially-extending concave portions.

A rotor polishing device, including a housing with a space therein for holding rotors in need of polishing, an inlet for pumping a polishing lapper into the housing, and a rotational assembly for rotating the rotors during the polishing process. The rotor polishing device is useful for polishing rotors commonly used by rotary screw compression systems.

A rotor polishing device, including a housing with a space therein for holding rotors in need of polishing, an inlet for pumping a polishing lapper into the housing, and a rotational assembly for rotating the rotors during the polishing process. The rotor polishing device is useful for polishing rotors commonly used by rotary screw compression systems.

The present disclosure includes charging members for charging abrasive particles into the surface of a lapping plate. The charging members include one or more channels to permit abrasive slurry to flow through when the charging member is in contact with the lapping plate.

A method for manufacturing a hypoid gear includes: a tooth cutting step of machining a shape of a tooth of the hypoid gear; a surface treatment step of forming a third intermediary gear provided with a hardened layer on a surface of the tooth; a lapping step of machining the third intermediary gear using an abrasive particle having a diameter of 14 ?m or less to form a fourth intermediary gear; and a shot peening step of spraying a particle having a diameter of 160 ?m or less onto the fourth intermediary gear.