Process for the locally restricted etching of a chromium layer

Abstract

A system and process for etching a portion of a chromium layer applied to a substrate is disclosed. The process includes exposing the substrate having the chromium layer to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism. An electron beam is directed onto a portion of the substrate that is to be etched.

1 . A process for etching a portion of a chromium layer applied to a substrate in which: 
 exposing the substrate having the chromium layer to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism; and    directing an electron beam onto a portion of the substrate that is to be etched.    
   
   
       2 . The process of  claim 1 , wherein halogen radicals and oxygen radicals are produced as a result of the dissociation, induced by electron collisions, of the compounds in the electron beam at the respectively predetermined rate, and 
 chromium is reacted with oxygen and halogen radicals, on account of the rates in each case being matched to the chromium etching mechanism, to form a volatile compound.    
   
   
       3 . The process of  claim 2 , wherein molecular chlorine Cl 2  and an oxygen-containing compound with a dissociation rate induced by electron collisions that is matched to the dissociation rate induced by electron collisions of the Cl 2  are provided for the compounds; and 
 chromium is reacted with oxygen and chlorine radicals to form volatile chromyl chloride CrO 2 Cl 2 .    
   
   
       4 . The process of  claim 3 , wherein water H 2 O, or nitrogen oxides N x O y  are used for the oxygen-containing compound.  
   
   
       5 . The process of  claim 3 , wherein dinitrogen oxide N 2 O is used for the oxygen-containing compound.  
   
   
       6 . The process as claimed in  claim 5 , comprising: 
 providing Cl 2  and N 2 O in the gas atmosphere in a ratio in a range between 10:1 and 1:10; and    providing the gas pressure in a range between 10 −4  and 10 −8  mbar.    
   
   
       7 . The process of  claim 1 , comprising providing Cl 2  and chlorine oxides Cl x O y , or Cl 2  and chlorine acids HClO x  for the compounds.  
   
   
       8 . The process of  claim 1 , comprising providing a chlorine-containing and oxygen-containing compound in the gas atmosphere.  
   
   
       9 . The process of  claim 7 , comprising providing a chlorine oxide Cl x O y  or a chlorine acid HClO x  as the compound.  
   
   
       10 . A process for repairing defects, caused by locally restricted chromium residues on transparent regions of a substrate, on masks having the opaque regions provided from chromium and transparent regions forming a pattern for lithographic imaging of the pattern from the mask onto a semiconductor wafer, comprising: 
 exposing the substrate having the chromium residue to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism; and    directing an electron beam onto the chromium residue on the substrate.    
   
   
       11 . The process of  claim 10 , wherein halogen radicals and oxygen radicals are produced as a result of the dissociation, induced by electron collisions, of the compounds in the electron beam at the respectively predetermined rate, and chromium residue is reacted with oxygen and halogen radicals, on account of the rates in each case being matched to the chromium etching mechanism, to form a volatile compound.  
   
   
       12 . The process of  claim 11 , wherein molecular chlorine Cl 2  and an oxygen-containing compound with a dissociation rate induced by electron collisions that is matched to the dissociation rate induced by electron collisions of the Cl 2  are provided for the compounds; and 
 chromium is reacted with oxygen and chlorine radicals to form volatile chromyl chloride CrO 2 Cl 2 .    
   
   
       13 . The process of  claim 12 , wherein water H 2 O, or nitrogen oxides N x O y  are used for the oxygen-containing compound.  
   
   
       14 . The process of  claim 13 , wherein dinitrogen oxide N 2 O is used for the oxygen-containing compound.  
   
   
       15 . The process as claimed in  claim 14 , comprising: 
 providing Cl 2  and N 2 O in the gas atmosphere in a ratio in a range between 10:1 and 1:10; and    providing the gas pressure in a range between 10 −4  and 10 −8  mbar.    
   
   
       16 . The process of  claim 11 , comprising providing Cl 2  and chlorine oxides Cl x O y , or Cl 2  and chlorine acids HClO x  for the compounds.  
   
   
       17 . The process of  claim 11 , comprising providing a chlorine-containing and oxygen-containing compound in the gas atmosphere.  
   
   
       18 . A process for etching a portion of a chromium layer applied to a substrate in which: 
 exposing the substrate having the chromium layer to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism; and    directing an electron beam onto a portion of the substrate that is to be etched,    wherein halogen radicals and oxygen radicals are produced as a result of the dissociation, induced by electron collisions, of the compounds in the electron beam at the respectively predetermined rate, and chromium is reacted with oxygen and halogen radicals, on account of the rates in each case being matched to the chromium etching mechanism, to form a volatile compound, and    wherein molecular chlorine Cl 2  and an oxygen-containing compound with a dissociation rate induced by electron collisions that is matched to the dissociation rate induced by electron collisions of the Cl 2  are provided for the compounds; and    chromium is reacted with oxygen and chlorine radicals to form volatile chromyl chloride CrO 2 Cl 2 .    
   
   
       19 . The process of  claim 18 , wherein water H 2 O, or nitrogen oxides N x O y  are used for the oxygen-containing compound.  
   
   
       20 . The process of  claim 18 , wherein dinitrogen oxide N 2 O is used for the oxygen-containing compound, and 
 providing Cl 2  and N 2 O in the gas atmosphere in a ratio in a range between 10:1 and 1:10; and    providing the gas pressure in a range between 10 −4  and 10 −8  mbar.    
   
   
       21 . A process for etching a portion of a chromium layer applied to a substrate comprising: 
 means for exposing the substrate having the chromium layer to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism; and    means for directing an electron beam onto a portion of the substrate that is to be etched.    
   
   
       22 . The process of  claim 21 , wherein halogen radicals and oxygen radicals are produced as a result of the dissociation, induced by electron collisions, of the compounds in the electron beam at the respectively predetermined rate, and 
 chromium is reacted with oxygen and halogen radicals, on account of the rates in each case being matched to the chromium etching mechanism, to form a volatile compound, wherein molecular chlorine Cl 2  and an oxygen-containing compound with a dissociation rate induced by electron collisions that is matched to the dissociation rate induced by electron collisions of the Cl 2  are provided for the compounds; and    chromium is reacted with oxygen and chlorine radicals to form volatile chromyl chloride CrO 2 Cl 2 .    
   
   
       23 . A system for etching a portion of a chromium layer applied to a substrate in which: 
 a gas configured to expose the substrate having the chromium layer to a gas atmosphere containing a halogen compound and an oxygen compound, each of the compounds being selected in such a way that halogen and oxygen radicals are produced, by dissociation induced by electron collisions, at a predetermined rate that is matched to a chromium etching mechanism; and    an electron beam focused onto a portion of the substrate that is to be etched.    
   
   
       24 . The system of  claim 23 , wherein halogen radicals and oxygen radicals are produced as a result of the dissociation, induced by electron collisions, of the compounds in the electron beam at the respectively predetermined rate, and 
 chromium is reacted with oxygen and halogen radicals, on account of the rates in each case being matched to the chromium etching mechanism, to form a volatile compound.    
   
   
       25 . The process of  claim 24 , wherein molecular chlorine Cl 2  and an oxygen-containing compound with a dissociation rate induced by electron collisions that is matched to the dissociation rate induced by electron collisions of the Cl 2  are provided for the compounds; and 
 chromium is reacted with oxygen and chlorine radicals to form volatile chromyl chloride CrO 2 Cl 2 .    
   
   
       26 . The system of  claim 23 , comprising: 
 a gas inlet positioned proximate the substrate, wherein the gas is provided via the gas inlet.