Method of forming metal line of inductor

Abstract

A method of forming a metal line of an inductor used in a Radio Frequency (RF) device, effectively removes polymer generated during an etching process to form trenches. The method removes the polymer using a radical having a high reactivity with the polymer. The method includes carrying out first main etching to form the trenches, carrying out ashing to remove polymer generated in the first main etching, and carrying out second main etching to form vias on the bottoms of the trenches.

1 . A method comprising:
 carrying out a first main etching to form trenches;   carrying out ashing to remove polymer generated in the first main etching; and   carrying out a second main etching to form vias on the bottoms of the trenches.   
   
   
       2 . The method of  claim 1 , wherein in the first main etching, the trenches are formed through reactive ion etching. 
   
   
       3 . The method of  claim 1 , wherein in the ashing, a nitrogen based radical having a high reactivity with the polymer is used as a process gas. 
   
   
       4 . The method of  claim 3 , wherein the polymer is removed from the sidewalls of the trenches. 
   
   
       5 . The method of  claim 1 , wherein in the ashing, a fluorine based radical having a high reactivity with the polymer is used as a process gas. 
   
   
       6 . The method of  claim 5 , wherein the polymer is removed from the sidewalls of the trenches. 
   
   
       7 . The method of  claim 1 , comprising carrying out ashing to remove the residue of a photoresist used to form the trenches in the first main etching. 
   
   
       8 . The method of  claim 7 , wherein the ashing to remove the residue of the photoresist is carried out in an oxygen atmosphere. 
   
   
       9 . The method of  claim 1 , including filling the trenches and vias with metal to form a metal line of an inductor. 
   
   
       10 . A method comprising:
 forming an insulating film over a substrate;   forming a photoresist pattern over the insulating film to form trenches;   forming the trenches on the insulating film through reactive ion etching using the photoresist pattern;   removing the photoresist pattern;   removing polymer in the trenches; and   forming vias on the bottoms of the trenches.   
   
   
       11 . The method of  claim 10 , wherein in the removal of the polymer, ashing using a nitrogen based radical as a process gas is carried out. 
   
   
       12 . The method of  claim 10 , wherein in the removal of the polymer, ashing using a fluorine based radical as a process gas is carried out. 
   
   
       13 . The method of  claim 10 , further comprising removing the residue of the photoresist pattern, after the removal of the photoresist pattern. 
   
   
       14 . The method of  claim 10 , further comprising forming a metal line of an inductor by filling the trenches and vias with a metal. 
   
   
       15 . An apparatus configured to:
 carry out a first main etching to form trenches;   carry out ashing to remove polymer generated in the first main etching; and   carry out a second main etching to form vias on the bottoms of the trenches.   
   
   
       16 . The apparatus of  claim 15 , configured to form the trenches in the first main etching through reactive ion etching. 
   
   
       17 . The apparatus  claim 15  configured to use as a process gas, in carrying out the ashing, one of a nitrogen based radical and a fluorine based radical, having a high reactivity with the polymer. 
   
   
       18 . The apparatus of  claim 17 , wherein the polymer is removed from the sidewalls of the trenches. 
   
   
       19 . The apparatus of  claim 15 , configured to carry out ashing, in an oxygen atmosphere, to remove the residue of a photoresist used to form the trenches in the first main etching. 
   
   
       20 . The apparatus of  claim 15 , configured to fill the trenches and vias with metal to form a metal line of an inductor.