To provide a plane lapping/polishing machine in which fluid such as lubricating oil is ensured to flow to the bottom of a fluid bearing pan of a fluid bearing and also in the inner and outer circumferential direction, thereby preventing the retention of the fluid in the bottom of the fluid bearing pan and in the inner and outer circumferential direction, and removing the impurities that settle into the bottom of the fluid bearing pan so as to make clean fluid, thus ensuring the function as a fluid bearing over a long period of time so as to enable smooth rotation.
In this plane lapping/polishing machine, an inner circumferential side recovery hole 27 is provided through an inner circumferential side bottom surface 52 adjacent to a lower bearing surface 51 in a groove of the fluid bearing pan 5. Also, an outer circumferential side recovery hole 28 is provided through an outer circumferential side bottom surface 53. A bypass circuit 29 communicates from inside to outside and vice versa between these inner circumferential side recovery hole 27 and outer circumferential side recovery hole 28 so as to eliminate uneven distribution. In addition, the fluid containing impurities that settle in the fluid bearing pan 5 is recovered.
|JP2002057131||MECHANISM FOR CONTROLLING SHAPE OF SURFACE TABLE FOR WAFER POLISHING|