Wafer polishing machine with fluid bearings

In a semiconductor wafer polishing machine of the type comprising at least one polishing pad assembly and at least one wafer holder positioned to hold a semiconductor wafer against the polishing pad assembly, the improvement comprising:

• a support positioned adjacent the polishing pad assembly, said support comprising a plurality of fluid bearings that support the polishing pad assembly on the support, each of said fluid bearings comprising:
• a respective fluid supply conduit connectable to a respective source of fluid at a respective pressure;
• a respective set of fluid pads, each in fluid communication with the respective fluid supply conduit, said fluid pads configured to direct fluid from the respective fluid supply conduit to support in part the polishing pad assembly on the support;
• wherein the fluid bearings comprise first and second plates;
• said first plate comprising a plurality of concentric grooves, each in communication with a respective one of the fluid supply conduits;
• said second plate comprising a plurality of sets of orifices, each set of orifices overlying and aligned with a respective concentric groove;
• said first and second plates secured together to hold the orifices in alignment with the respective grooves;
• each fluid pad formed in the second plate in communication with a respective orifice.