Apparatus for processing a wafer-shaped article

1 . An apparatus for processing a wafer-shaped article, the apparatus comprising a support configured to support the wafer-shaped article during a processing operation to be performed on the wafer-shaped article; wherein:

the support comprises a support body and a plurality of gripping pin assemblies adapted and positioned relative to the support body for gripping the wafer-shaped article, wherein the gripping pin assemblies are rotatable between a gripping configuration in which the gripping pin assemblies are arranged to grip the wafer-shaped article, and a non-gripping configuration in which the gripping pin assemblies are not arranged to grip the wafer-shaped article; and

the apparatus comprises a detector configured to directly or indirectly detect a configuration of the gripping pin assemblies,

wherein

the support body comprises a second gear for driving rotation of the gripping pin assemblies,

the detector is configured to directly or indirectly detect a rotational position of the second gear,

each of the gripping pin assemblies comprises a first gear that is located inside the support body, and

the second gear is meshed with each of the first gears so that rotation of the second gear causes synchronized rotation of the gripping pin assemblies.

2 . The apparatus according to claim 1 , wherein the detector is configured to directly or indirectly detect a rotational position of one or more of the gripping pin assemblies.

3 . The apparatus according to claim 1 , wherein:

the detector is configured to directly or indirectly detect when the gripping pin assemblies are in the gripping configuration; and/or

the detector is configured to directly or indirectly detect when the gripping pin assemblies are in the non-gripping configuration.

4 . The apparatus according to claim 1 , wherein:

the detector comprises a rotatable arm, wherein rotation of the rotatable arm is directly or indirectly coupled to rotation of the gripping pin assemblies, so that a rotational position of the rotatable arm is directly related to rotational positions of the gripping pin assemblies; and

the detector is configured to detect the rotational position of the rotatable arm.

5 . The apparatus according to claim 1 , wherein:

the detector comprises a rotatable arm, wherein rotation of the rotatable arm is directly or indirectly coupled to rotation of the second gear, so that the rotational position of the rotatable arm is directly related to the rotational position of the second gear; and

the detector is configured to detect a rotational position of the rotatable arm.

6 . The apparatus according to claim 5 , wherein:

the rotatable arm is rotatably coupled to the support at a first rotatable connection; and

the rotatable arm is rotatably coupled to the second gear at a second rotatable connection, so that rotation of the second gear causes the rotatable arm to be rotated around the first rotatable connection relative to the support.

7 . The apparatus according to claim 4 , wherein:

the detector comprises a radiation source and a radiation sensor;

the rotatable arm is arranged to interrupt a radiation path between the radiation source and the radiation sensor when the gripping pin assemblies are in a predetermined configuration; and

the detector is configured to detect when the radiation path between the radiation source and radiation sensor is interrupted.

8 . The apparatus according to claim 7 , wherein the radiation path is along a longitudinal axis of the support.

9 . The apparatus according to claim 7 , wherein:

the radiation source is below the support and the radiation sensor is above the support, and the support includes a transparent window; or

the radiation source is above the support and the radiation sensor is below the support, and the support includes a transparent window; or

the radiation sensor and the radiation source are below the support, and the support comprises a reflector for reflecting radiation from the radiation source to the radiation sensor.

10 . The apparatus according to claim 1 , wherein the detector comprises a distance measuring detector.

11 . The apparatus according to claim 4 , wherein:

the detector comprises a distance measuring detector; and

the distance measuring detector is configured to measure a distance to the rotatable arm.

12 . The apparatus according to claim 11 , wherein:

the distance measuring detector is configured to measure a distance to the rotatable arm in a direction parallel to a rotation axis of the rotatable arm; and

the rotatable arm has a thickness that varies along a direction perpendicular to the rotation axis of the rotatable arm, so that rotation of the rotatable arm causes the distance between the rotatable arm and the distance measuring detector to vary based on the varying thickness of the rotatable arm.

13 . The apparatus according to claim 1 , wherein the second gear is a ring gear.

14 . The apparatus according to claim 1 , wherein each of the gripping pin assemblies comprises:

a body;

the first gear at a first end of the body; and

a gripping part at a second end of the body for gripping the wafer-shaped article.

15 . The apparatus according to claim 14 , wherein the gripping part comprises a longitudinal protrusion from the second end of the body, the longitudinal protrusion being spaced apart from a longitudinal axis of the gripping pin assembly.

16 . The apparatus according to claim 1 , wherein the gripping pin assemblies are positioned in a circular series surrounding an area where the wafer-shaped article is to be positioned on the support, and in the gripping configuration the gripping pin assemblies are configured to make edge contact with the wafer-shaped article thereby to constrain the wafer-shaped article from lateral movement away from a pre-determined position.

17 . The apparatus according to claim 1 , wherein:

the apparatus is configured to apply a rotational force to the gripping pin assemblies when the gripping pin assemblies are in the gripping configuration, so that the gripping pin assemblies apply a gripping force to the wafer-shaped article; and

the rotational force is arranged to rotate the gripping pin assemblies away from the gripping configuration if the wafer-shaped article is lost or broken.