Polishing apparatus and polishing method

Abstract

A polishing apparatus comprises a first polishing table having a first polishing surface, a substrate carrier for holding a substrate and positioning the substrate so as to bring a surface of the substrate into contact with the first polishing surface, a pressing mechanism for pressing, against the first polishing surface, the surface of the substrate which has been brought into contact with the first polishing surface by the substrate carrier, a retainer ring mounted on the substrate carrier so as to surround the substrate which has been pressed against the first polishing surface by the pressing mechanism, and a retainer-ring-position-adjustment mechanism for adjustably positioning the retainer ring relative to the substrate, which has been pressed against the first polishing surface, in directions toward and away from the first polishing surface.

1 . A substrate carrier system comprising:
 a substrate carrier for holding a substrate and positioning the substrate so as to bring a surface of the substrate into contact with a polishing surface during polishing;   a substrate carrier drive shaft connected to said substrate carrier for driving, raising and lowering said substrate carrier;   a ball screw and a ball nut connected to said substrate carrier drive shaft;   a pulse motor coupled to said ball screw for raising and lowering said substrate carrier until at a desired vertical position;   a fluid pressure source to apply a pressurized fluid above the substrate; and   a control mechanism for fixing a vertical position of said substrate carrier by said pulse motor, said ball screw and said ball nut until said substrate carrier is fixed at a desired vertical position, and supplying a pressurization fluid above said substrate to press the substrate against said polishing surface.   
     
     
         2 . A substrate carrier system according to  claim 1 , further comprising a resilient member for defining inflatable chambers for applying said fluid pressure onto the substrate. 
     
     
         3 . A substrate carrier system according to  claim 1 , wherein said control mechanism lowers said substrate carrier until said substrate carrier is brought into contact with said polishing surface, and then raises said substrate carrier until said substrate carrier is raised at a certain distance from said polishing surface to fix said vertical position of said substrate carrier. 
     
     
         4 . A substrate carrier system according to  claim 3 , wherein said substrate carrier comprises a retainer ring for surrounding said substrate, and said contact of said substrate carrier with said polishing surface is detected by judging whether said retainer ring contacts with said polishing surface. 
     
     
         5 . A substrate carrier system according to  claim 3 , wherein said contact of said substrate carrier with said polishing surface is detected by judging whether said substrate held by said substrate carrier contacts with said polishing surface. 
     
     
         6 . A substrate carrier system according to  claim 3 , further comprising a load cell installed at a lower end of said substrate carrier drive shaft, wherein said load cell detects the contacts said substrate carrier with said polishing surface. 
     
     
         7 . A substrate carrier system according to  claim 3 , wherein said certain distance from said polishing surface is less than a thickness of said substrate. 
     
     
         8 . A substrate carrier system according to  claim 2 , wherein said resilient member defines a plurality of said inflatable chambers over radial direction of said substrate carrier.