A chuck-claw coupling mechanism includes a coupling member provided in a master jaw, a first resilient member, and an operation unit. The coupling member is movable between a coupling position at which the coupling member is coupled to the claw, and a separation position at which the coupling member is separated from the claw. The first resilient member urges the coupling member toward the coupling position. The operation unit moves the coupling member to the separation position.

A chuck-claw coupling mechanism includes a coupling member provided in a master jaw, a first resilient member, and an operation unit. The coupling member is movable between a coupling position at which the coupling member is coupled to the claw, and a separation position at which the coupling member is separated from the claw. The first resilient member urges the coupling member toward the coupling position. The operation unit moves the coupling member to the separation position.

A chuck-claw guide structure includes a guide-space delimiting part that delimits a guide space in communication with an attachment groove, and a regulation part provided on the guide-space delimiting part. The guide-space delimiting part has a contact surface configured to regulate the claw in contact therewith at a position along the attachment groove in a first direction. The regulation part is configured to regulate the claw at a position along the attachment groove in a second direction different from the first direction.

A stair form member attached jaw is installed with the stair form member provided at the bottom face of the soft jaw. The stair form member is held between a pair of grips in the jaw installing groove of the master jaw from both sides of the radial direction, thereby pulling the stair form member to the bottom direction of the jaw installing groove. The position of the radial direction of the soft jaw is determined by the engagement between the bottom face of the soft jaw and the upper serration faces of the master jaw; and the position of the soft jaw in the tangent line is determined by the close contact of the stair form member to the side face of the jaw installing groove.

A chuck-claw guide structure includes a guide-space delimiting part that delimits a guide space in communication with an attachment groove, and a regulation part provided on the guide-space delimiting part. The guide-space delimiting part has a contact surface configured to regulate the claw in contact therewith at a position along the attachment groove in a first direction. The regulation part is configured to regulate the claw at a position along the attachment groove in a second direction different from the first direction.

A stair form member attached jaw is installed with the stair form member provided at the bottom face of the soft jaw. The stair form member is held between a pair of grips in the jaw installing groove of the master jaw from both sides of the radial direction, thereby pulling the stair form member to the bottom direction of the jaw installing groove. The position of the radial direction of the soft jaw is determined by the engagement between the bottom face of the soft jaw and the upper serration faces of the master jaw; and the position of the soft jaw in the tangent line is determined by the close contact of the stair form member to the side face of the jaw installing groove.

A structure, including first and second portions respectively having a serration in which peaks and valleys are continuous, and configured to adjust relative positions of the first and second portions in an adjustment direction by interlocking the peaks and valleys with each other. The adjustment direction is a direction in which the peaks and valleys of the serration are continuous; a fixing portion configured to maintain a defined state. The defined state is a state in which the peaks and valleys are interlocked with each other and the relative positions of the first and second portions are fixed; and a positioning mechanism provided on the second portion or the fixing portion, and having a contact portion configured to contact the first portion in the defined state.

An apparatus for processing wafer-shaped articles includes a rotary chuck adapted to hold a wafer shaped article thereon. The rotary chuck includes a peripheral series of pins configured to contact an edge region of a wafer-shaped article. Each of the pins projects upwardly from the rotary chuck, and each of the pins is individually secured to the rotary chuck by a respective connecting mechanism. Any selected one of the pins can be removed from the rotary chuck by disconnecting its corresponding connecting mechanism without removing any structure of the rotary chuck that surrounds any others of the pins.