Process for forming a pattern including on a semiconductor device

Abstract

An objective of this invention is to prevent resist poisoning and sensitivity deterioration in a chemically amplified resist. The chemically amplified resist comprises a base resin, a photoacid generator and a salt exhibiting buffer effect in the base resin.

1 . A process for manufacturing a semiconductor device, comprising the steps of;
 forming a film to be etched on a semiconductor substrate,   applying a chemically amplified resist composition on the film to be etched to form a resist film,   patterning the resist film and etching the film to be etched, using the patterned resist film as a mask:   wherein the chemically amplified resist composition comprises;   a base resin,   a photoacid generator which generates an acid by exposure, and   a salt exhibiting buffer effect in the base resin.   
     
     
         2 . A process for manufacturing a semiconductor device, comprising the steps of;
 forming a film to be etched on a semiconductor substrate,   on the film to be etched, forming a first resist film patterned in a predetermined shape and using the first resist film as a mask, etching the film to be etched to form a concave,   removing the first resist film,   on the film to be etched, applying a chemically amplified resist composition, which is then dried to form a second resist film,   patterning the second resist film to form an opening such that at least part of the region where the concave has been formed is exposed, and   etching the film to be etched, using the patterned second resist film as a mask:   wherein the chemically amplified resist composition comprises;   a base resin,   a photoacid generator which generates an acid by exposure, and   a salt exhibiting buffer effect in the base resin.   
     
     
         3 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the step of removing the first resist film comprises removing a part of the first resist film with an amine stripper. 
     
     
         4 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the film to be etched contains nitrogen. 
     
     
         5 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the film to be etched contains nitrogen. 
     
     
         6 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the film to be etched is a film having a porous structure with a specific dielectric constant of 3 or less. 
     
     
         7 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the film to be etched is a film having a porous structure with a specific dielectric constant of 3 or less. 
     
     
         8 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the salt comprises the acid generated from the photoacid generator by exposure. 
     
     
         9 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the salt comprises the acid generated from the photoacid generator by exposure. 
     
     
         10 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the salt is a sulfonate. 
     
     
         11 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the salt is a sulfonate. 
     
     
         12 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the salt is an amine salt. 
     
     
         13 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the salt is an amine salt. 
     
     
         14 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the salt is a salt of an alkanolamine or alkoxyalkylamine with a sulfonic acid. 
     
     
         15 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the salt is a salt of an alkanolamine or alkoxyalkylamine with a sulfonic acid. 
     
     
         16 . The process for manufacturing a semiconductor device as claimed in  claim 1 , wherein the base resin is a resin whose alkali solubility is changed by the action of the acid. 
     
     
         17 . The process for manufacturing a semiconductor device as claimed in  claim 2 , wherein the base resin is a resin whose alkali solubility is changed by the action of the acid. 
     
     
         18 . A process for forming a pattern, comprising the steps of;
 applying a chemically amplified resist composition on a material to be etched to form a resist film,   patterning the resist film, and   etching and patterning the material to be etched, using the patterned resist film as a mask:   wherein the chemically amplified resist composition comprises;   a base resin,   a photoacid generator which generates an acid by exposure, and   a salt exhibiting buffer effect in the base resin.   
     
     
         19 . The process for patterning as claimed in  claim 18 , wherein the material to be etched contains nitrogen. 
     
     
         20 . The process for patterning as claimed in  claim 18 , wherein the film to be etched is a film having a porous structure with a specific dielectric constant of 3 or less. 
     
     
         21 . The process for patterning as claimed in  claim 18 , wherein the salt comprises the acid generated from the photoacid generator by exposure. 
     
     
         22 . The process for patterning as claimed in  claim 18 , wherein the salt is a sulfonate. 
     
     
         23 . The process for patterning as claimed in  claim 18 , wherein the salt is an amine salt. 
     
     
         24 . The process for patterning as claimed in  claim 18 , wherein the salt is a salt of an alkanolamine or alkoxyalkylamine with a sulfonic acid. 
     
     
         25 . The process for patterning as claimed in  claim 18 , wherein the base resin is a resin whose alkali solubility is changed by the action of the acid.