Method of producing mold

Abstract

A method for producing a mold, used for imprint, by dry etching a substrate made of quartz by using a dry etching apparatus, the method includes: a mask forming step for forming an etching mask having a concave and convex pattern on the substrate, and an etching step for forming a protective film on a side wall of the etching mask and for etching the substrate at the same time.

1 . A method for producing a mold, used for imprint, by dry etching a substrate made of quartz by using a dry etching apparatus, the method comprising:
 a mask forming step for forming an etching mask having a concave and convex pattern on the substrate, and   an etching step for forming a protective film on a side wall of the etching mask and for etching the substrate at the same time.   
     
     
         2 . The method of  claim 1 , wherein the etching step controls a relationship between a film forming rate of the protective film and an etching rate of the substrate. 
     
     
         3 . The method of  claim 1 , wherein the etching step controls the relationship between the film forming rate of the protective film and an etching rate of the substrate by controlling a O 2 /CF ratio of oxygen and fluorocarbon included in an etching gas introduced into a vacuum chamber of the dry etching apparatus. 
     
     
         4 . The method of  claim 3 , wherein the etching step reduces a ratio of the etching rate of the substrate relative to the film forming rate of the protective film by causing the O 2 /CF ratio to become larger, and increases the ratio of the etching rate of the substrate relative to the film forming rate of the protective film by causing the O 2 /CF ratio to become smaller. 
     
     
         5 . The method of  claim 1 , wherein the etching step controls the relationship between the film forming rate of the protective film and the etching rate of the substrate by controlling a biasing electric power applied to the substrate. 
     
     
         6 . The method of  claim 1 , further comprising a bias power determination step for determining a biasing electric power applied to the substrate with reference to a map in which the biasing electric power applied to the substrate corresponds to a relationship between the film forming rate of the protective film and the etching rate of the substrate. 
     
     
         7 . The method of  claim 1 , further comprising a fluorocarbon components determination step for determining a component of the fluorocarbon with reference to a map in which the component of the fluorocarbon corresponds to a relationship between the film forming rate of the protective film and the etching rate of the substrate. 
     
     
         8 . The method of  claim 1 , further comprising a gas ratio determination step for determining the O 2 /CF ratio with reference to a map in which the O 2 /CF ratio corresponds to a relationship between the film forming rate of the protective film and the etching rate of the substrate. 
     
     
         9 . The method of  claim 8 , further comprising an etching rate determination step for determining the etching rate of the substrate relative to O 2 /CF ratio determined with reference to a map in which the O 2 /CF ratio corresponds to the etching rate of the substrate. 
     
     
         10 . The method of  claim 9 , further comprising a mask thickness determination step for determining a thickness of the etching mask needed on the basis of the etching rate determined and the etching time determined. 
     
     
         11 . The method of  claim 1 , wherein the protective film includes SiO 2 .