Polishing head testing with movable pedestal

A test station for testing a polishing head using a test wafer, the polishing head for planarizing a semiconductor wafer, the station comprising:

• a frame;
• a pedestal having a central wafer support surface adapted to support a test wafer;
• a test wafer positioner having a first plurality of test wafer engagement members positioned around said central wafer support surface;
• a polishing head mount adapted to mount said polishing head over said central wafer support surface;
• a pneumatic circuit adapted to couple to said polishing head and to pressure test said polishing head;
• a head mount actuator, coupled to said frame and said polishing head mount and adapted to move said polishing head in a vertical direction relative to said central wafer support surface;
• and
• a pedestal actuator, coupled to said frame and said pedestal and adapted to move said central wafer support surface in a vertical direction relative to said frame between a first vertical position vertically displaced from said polishing head of said polishing head mount, and a second vertical position vertically closer to said polishing head of said polishing head mount as compared to the first vertical position,
• wherein the first plurality of test wafer engagement members each includes a respective wafer engagement surface adapted to engage and position said test wafer with respect to said central wafer support surface when the central wafer support surface is at the first vertical location, and
• wherein the central wafer support surface is below the respective wafer engagement surfaces of the first plurality of test wafer engagement members when the central wafer support surface is at the first vertical position, and is configured to lift said test wafer off and away from the respective wafer engagement surfaces of the first plurality of test wafer engagement members when the central wafer support surface is moved from the first vertical position to the second vertical position.