Patent ID: 9464884
Filing Date: 2016-10-11
CPC Classification: G01B,H01L

Claim Text:
1. A method for determining an X-Y position of an axis of rotation of a substrate holding means, the substrate holding means being configured to hold a substrate, the X-Y position being on an X-Y coordinate system, the axis of rotation being perpendicular to the X-Y coordinate system, the substrate holding means being configured to rotate around the axis of rotation, the method, comprising the steps of: determining a first X-Y reference position RP of a reference labeling provided on the substrate holding means, rotating the substrate holding means by a defined angle of rotation R around the axis of rotation, determining a second X-Y reference position RP′ of the reference labeling that is changed by the step of rotating, calculating the X-Y position of the axis of rotation in a plane of the substrate based on said first X-Y reference position RP and said second X-Y reference position RP′, and determining an alignment error of contact points of the substrate, wherein the substrate is fixed on the substrate holding means during the step of determining the alignment error and the step of calculating.