hi winThree moving HIWIN axes with spindle drive are used here for wafer centring and angular alnment. Depending on the alner model, an X-Y unit or an X-Z unit is used. Due toHIWIN has come up with the ideal solution in the form of its CRB series of crossed roller bearings. The crossed arrangement of the rollers at an angle of 90° means that the bearings are able to