Planarization polishing method and method for manufacturing semiconductor device

Abstract

Disclosed herein is a planarization polishing method for polishing a polishing-target wafer for a planarized surface, the method including the step of polishing a polishing-target surface into a planarized surface by using polishing slurry that contains an abrasive grain and a surfactant encapsulated through surface coating.

1 . A planarization polishing method for polishing a polishing-target wafer for a planarized surface, the method comprising the step of
 polishing a polishing-target surface into a planarized surface by using polishing slurry that contains an abrasive grain and a surfactant encapsulated through surface coating.   
   
   
       2 . The planarization polishing method according to  claim 1 , wherein
 the polishing-target surface is an oxide film.   
   
   
       3 . The planarization polishing method according to  claim 2 , wherein
 ceria-based polishing slurry that contains a ceria particle as the abrasive grain is used.   
   
   
       4 . The planarization polishing method according to  claim 2 , wherein
 the surfactant acts on the oxide film that is to be polished.   
   
   
       5 . The planarization polishing method according to  claim 2 , wherein
 the oxide film is a silicon oxide film formed across a trench in a substrate and an underlying silicon nitride film outside the trench, and   the surfactant acts on the silicon oxide film.   
   
   
       6 . The planarization polishing method according to  claim 2 , wherein
 polishing is carried out by using first polishing slurry that contains an abrasive grain and a surfactant encapsulated through surface coating until a projection region on a polishing-target surface is planarized, and   subsequent polishing is carried out by using second polishing slurry that contains no surfactant.   
   
   
       7 . The planarization polishing method according to  claim 1 , wherein
 mechanical strength of a coating film of the encapsulated surfactant is equal to or lower than mechanical strength by polishing pressure and shear force.   
   
   
       8 . A method for manufacturing a semiconductor device, the method comprising the step of
 for formation of a shallow trench isolation region serving as an element isolation region, polishing an oxide film deposited on a region other than a trench of a semiconductor substrate for a planarized surface by using polishing slurry that contains an abrasive grain and a surfactant encapsulated through surface coating.   
   
   
       9 . The method for manufacturing a semiconductor device according to  claim 8 , wherein
 the oxide film on the region other than the trench is deposited on an underlying film formed of a nitride film.   
   
   
       10 . The planarization polishing method according to  claim 8 , wherein
 ceria-based polishing slurry that contains a ceria particle as the abrasive grain is used.   
   
   
       11 . The planarization polishing method according to  claim 8 , wherein
 the surfactant acts on the oxide film that is to be polished.   
   
   
       12 . The method for manufacturing a semiconductor device according to  claim 8 , wherein
 polishing is carried out by using first polishing slurry that contains an abrasive grain and a surfactant encapsulated through surface coating until a projection region of the oxide film is planarized, and   subsequent polishing is carried out by using second polishing slurry that contains no surfactant.   
   
   
       13 . The method for manufacturing a semiconductor device according to  claim 8 , wherein
 mechanical strength of a coating film of the encapsulated surfactant is equal to or lower than mechanical strength by polishing pressure and shear force.