Holder for flat workpieces, particularly semiconductor wafers

Not applicable. A holder for flat workpieces, particularly semiconductor wafers, particularly in an apparatus for chemico-mechanically polishing the semiconductor wafers, comprising a disk-like head which is adapted to be connected to a spindle adjustable in height at the upper surface and has a support plate at the lower side which, via a universal joint, is coupled to a carrier portion disposed above the support plate or the spindle and which has a number of vertical bores which extend to the underside of the support plate and can be optionally connected to a vacuum and/or a fluid source under pressure, where the support plate is guided to be movable in height in the carrier portion and displacing means are provided between the carrier portion and the support plate to displace the support plate with respect to the carrier portion and to exert a predetermined pressure on the workpiece, characterized in that a ring-shaped loading member of limited width is provided which is movably supported in an axially parallel way in the support plate near its border and is displaceable by a loading mechanism towards a workpiece retained by the support plate and is displaceable away therefrom to apply a predetermined pressure to the workpiece.