Method for dry etching interlayer insulating film

Abstract

A method for dry etching an interlayer insulating film with an ArF resist or KrF resist thereon comprises dry etching fine features into the interlayer insulating film with an etching gas in such a manner as to form a polymer film on the ArF or KrF resist from the etching gas, wherein the etching gas is introduced under a pressure of 0.5 Pa or less, and wherein a Fourier transform infrared spectrum of the polymer film includes a C—F bond peak at about 1200 cm −1 , a C—N bond peak at about 1600 cm −1 , and a C—H bond peak at about 3300 cm −1 .

1 . A method for dry etching an interlayer insulating film with an ArF resist or KrF resist thereon, comprising:
 dry etching fine features into said interlayer insulating film with an etching gas in such a manner as to form a polymer film on said ArF or KrF resist from said etching gas,   wherein said etching gas is introduced under a pressure of 0.5 Pa or less, and   wherein a Fourier transform infrared spectrum of said polymer film includes a C—F bond peak at about 1200 cm − , a C—N bond peak at about 1600 cm − , and a C—H bond peak at about 3300 cm −1 .   
   
   
       2 - 9 . (canceled) 
   
   
       10 . The method according to  claim 1 , wherein said interlayer insulating film is an SiOCH-based material. 
   
   
       11 . The method according to  claim 1 , wherein said etching gas includes a CF-based gas, a N-containing gas, and a low molecular weight hydrocarbon gas. 
   
   
       12 . The method according to  claim 11 , wherein said low molecular weight hydrocarbon is selected from the group consisting of CH 4 , C 2 H 6 , C 3 H 8 , C 4 H 10 , and C 2 H 2 . 
   
   
       13 . The method according to  claim 11 , wherein said N-containing gas includes at least one gas selected from the group consisting of nitrogen gas, NO x , NH 3 , methylamine, and dimethylamine. 
   
   
       14 . The method according to  claim 1 , wherein said etching gas includes a C x F y H z  gas and a N-containing gas. 
   
   
       15 . The method according to  claim 14 , wherein said low molecular weight hydrocarbon is selected from the group consisting of CH 4 , C 2 H 6 , C 3 H 8 , C 4 H 10 , and C 2 H 2 . 
   
   
       16 . The method according to  claim 14 , wherein said N-containing gas includes at least one gas selected from the group consisting of nitrogen gas, NO x , NH 3 , methylamine, and dimethylamine. 
   
   
       17 . The method according to  claim 11 , wherein said CF-based gas includes at least one gas selected from the group consisting of CF 4 , C 3 F 8 , C 2 F 6 , C 4 F 8 , C 5 F 8  and C x F y I. 
   
   
       18 . The method according to  claim 17 , wherein said low molecular weight hydrocarbon is selected from the group consisting of CH 4 , C 2 H 6 , C 3 H 8 , C 4 H 10 , and C 2 H 2 . 
   
   
       19 . The method according to  claim 14 , wherein said C x F y H z  gas is CHF 3  gas. 
   
   
       20 . The method as claimed in  claim 17 , wherein said C x F y I gas is C 3 F 7 I gas or CF 3 I gas.