Patent ID: 8801069

Claim:
An apparatus for gripping a substrate on its peripheral edge, the apparatus comprising: a substrate support having proximate and distal ends; at least one distal rest pad disposed at the distal end of the substrate support, the at least one distal rest pad includes a back stop portion and is configured to support the peripheral edge of the substrate; at least one proximate rest pad disposed at the proximate end of the substrate support, the at least one proximate rest pad being configured to support the peripheral edge of the substrate; and an active contact member assembly disposed at the proximate end of the substrate support, the active contact member assembly including a pusher member, a contact member and a rotatable coupling member that are substantially linearly reciprocably movable towards the distal end of the substrate support for urging the substrate against the back stop portion of the at least one distal rest pad, the contact member being movably secured to the pusher member by the rotatable coupling member so that the contact member is substantially free to rotate about a center axis of the rotatable coupling member substantially on contact with the substrate and a center axis of the rotatable coupling member is aligned with an axis of the pusher member.