Polishing method

Abstract

A polishing method can obtain a good polishing profile which, for example, will not cause peeling of a semiconductor layer from a silicon substrate. The polishing method includes: positioning a polishing head at a position above a polishing start position in an edge portion of a rotating substrate; lowering a polishing tool of the polishing head until the polishing tool comes into contact with the polishing start position in the edge portion of the rotating substrate and a pressure between the polishing tool and the polishing start position reaches a set pressure; allowing the polishing tool to stay at the polishing start position for a predetermined amount of time; and then moving the polishing head toward a peripheral end of the substrate while keeping the polishing tool in contact with the edge portion of the rotating substrate at the set pressure.

1 . A polishing method comprising:
 positioning a polishing head at a position above a polishing start position in an edge portion of a rotating substrate;   lowering the polishing head and bringing a polishing tool of the polishing head into contact with the polishing start position in the edge portion of the rotating substrate at a predetermined pressure;   allowing the polishing tool to stay at the polishing start position for a predetermined amount of time; and then   moving the polishing head toward a peripheral end of the substrate while keeping the polishing tool in contact with the edge portion of the rotating substrate at the predetermined pressure.   
     
     
         2 . The polishing method according to  claim 1 , herein the predetermined amount of time is at least one second. 
     
     
         3 . The polishing method according to  claim 1 , wherein the polishing tool is a polishing tape which travels in one direction at a predetermined speed when it polishes the edge portion of the substrate. 
     
     
         4 . The polishing method according to  claim 1 , wherein a bevel portion of the substrate is polished while polishing the edge portion of the substrate by keeping the polishing tool in contact with the edge portion of the rotating substrate. 
     
     
         5 . A polishing method comprising:
 positioning a polishing head at a position above a polishing start position in an edge portion of a rotating substrate;   lowering a polishing tool of the polishing head until the polishing tool comes into contact with the polishing start position in the edge portion of the rotating substrate and a pressure between the polishing tool and the polishing start position reaches a set pressure;   allowing the polishing tool to stay at the polishing start position for a predetermined amount of time; and then   moving the polishing head toward a peripheral end of the substrate while keeping the polishing tool in contact with the edge portion of the rotating substrate at the set pressure.   
     
     
         6 . The polishing method according to  claim 5 , wherein the predetermined amount of time is at least one second. 
     
     
         7 . The polishing method according to  claim 5 , wherein during a period after contact of the polishing tool with the edge portion of the substrate until the start of movement of the polishing head, the contact pressure of the polishing tool on the edge portion of the substrate is kept higher than the set pressure. 
     
     
         8 . The polishing method according to  claim 5 , wherein after lowering the polishing tool and bringing the polishing tool into contact with the polishing start position in the edge portion of the rotating substrate at a lower pressure than the set pressure, the pressure of the polishing tool on the edge portion of the substrate is increased to the set pressure. 
     
     
         9 . The polishing method according to  claim 5 , wherein the polishing tool is a polishing tape which travels in one direction at a predetermined speed when it polishes the edge portion of the substrate. 
     
     
         10 . The polishing method according to  claim 5 , wherein a bevel portion of the substrate is polished while polishing the edge portion of the substrate by keeping the polishing tool in contact with the edge portion of the rotating substrate. 
     
     
         11 . A polishing method comprising:
 a first polishing including
 (a) positioning a polishing head at a position above a polishing start position in an edge portion of a rotating substrate, 
 (b) lowering a polishing tool of the polishing head until the polishing tool comes into contact with the polishing start position in the edge portion of the rotating substrate and a pressure between the polishing tool and the polishing start position reaches a set pressure, and 
 (c) moving the polishing head toward a peripheral end of the substrate at a first movement speed while keeping the polishing tool in contact with the edge portion of the rotating substrate; and 
   a second polishing including
 (d) moving the polishing head toward the peripheral end of the substrate at a second movement speed while keeping the polishing tool in contact with the edge portion of the rotating substrate. 
   
     
     
         12 . The polishing method according to  claim 11 , wherein the second movement speed of the polishing head is higher than the first movement speed of the polishing head. 
     
     
         13 . The polishing method according to  claim 11 , wherein when moving the polishing head toward the peripheral end of the substrate at the first movement speed, the contact pressure of the polishing tool on the edge portion of the substrate is kept higher than the set pressure. 
     
     
         14 . The polishing method according to  claim 11 , wherein after lowering the polishing tool and bringing the polishing tool into contact with the polishing start position in the edge portion of the rotating substrate at a lower pressure than the set pressure, the pressure of the polishing tool on the edge portion of the substrate is increased to the set pressure. 
     
     
         15 . The polishing method according to  claim 11 , wherein the polishing tool is a polishing tape which travels in one direction at a predetermined speed when it polishes the edge portion of the substrate. 
     
     
         16 . The polishing method according to  claim 11 , wherein a bevel portion of the substrate is polished while polishing the edge portion of the substrate by keeping the polishing tool in contact with the edge portion of the rotating substrate.