In a substrate processing apparatus, a shield plate includes a first chucking magnetic material (441). The shield plate is moved up and down by a chamber opening-and-closing mechanism. A substrate holding part includes a movable chuck member (412) and a fixed chuck member. The movable chuck member (412) includes a second chucking magnetic material (442). When the shield plate is moved down, the shield plate comes in close proximity to the upper surface of a substrate (9), and the first chucking magnetic material (441) comes in close proximity to the second chucking magnetic material (442). The substrate (9) is held by magnetic action between the first chucking magnetic material (441) and the second chucking magnetic material (442). It is thus possible to hold the substrate (9) with a simple structure.

A chuck for gripping a workpiece includes: a chuck body; a jaw connected to the chuck body for constrained movement relative to the chuck body along a jaw path in jaw-closing and jaw-opening directions; an actuator body connected to the chuck body for constrained movement relative to the chuck body along an actuator path; and a slider body connected to the chuck body for constrained movement relative to the chuck body along a slider body path. The slider body is connected to the jaw for constrained movement relative to the jaw along a slider-body-to-jaw path. The slider body is connected to the actuator body for constrained movement relative to the actuator body along a slider-body-to-actuator-body path.

A chuck for gripping a workpiece includes: a chuck body; a jaw connected to the chuck body for constrained movement relative to the chuck body along a jaw path in jaw-closing and jaw-opening directions; an actuator body connected to the chuck body for constrained movement relative to the chuck body along an actuator path; and a slider body connected to the chuck body for constrained movement relative to the chuck body along a slider body path. The slider body is connected to the jaw for constrained movement relative to the jaw along a slider-body-to-jaw path. The slider body is connected to the actuator body for constrained movement relative to the actuator body along a slider-body-to-actuator-body path.

In a component for connecting a shaft to a clamping holder that can receive a rotor, the clamping holder is able to be inserted into a cup-shaped housing and is able to be fixed there by fasteners. On the housing base of the housing is a connector for connecting the housing to the shaft in a torque-proof manner. The fasteners are arranged with their base surface on the outer lateral surface of the housing, and can be brought into engagement with the clamping holder by bores present in the housing. The fasteners have at least one recess in the base surface, such that they rest with their base surface on the outer lateral surface only in some regions.