Method and apparatus for cleaning a substrate processing chamber

Abstract

A method of cleaning process residues formed on surfaces in a chamber during processing of a substrate in the chamber includes first and second steps. In a first cleaning step, a first energized cleaning gas having a first chlorine-containing gas and oxygen is provided in the chamber and then exhausted. In a second cleaning step, a second energized cleaning gas having a second chlorine-containing gas and oxygen is provided in the chamber and then exhausted.

What is claimed is:  
     
         1 . A method of cleaning process residues formed on surfaces in a chamber during processing of a substrate in the chamber, the method comprising: 
 (a) a first cleaning step comprising: 
 providing a first energized cleaning gas in the chamber, the first energized cleaning gas comprising a first chlorine-containing gas and oxygen; and  
 exhausting the first cleaning gas; and  
   (b) a second cleaning step comprising: 
 providing a second energized cleaning gas in the chamber, the second energized cleaning gas comprising a second chlorine-containing gas and oxygen; and  
 exhausting the second cleaning gas.  
   
     
     
         2 . A method according to  claim 1  wherein the second energized cleaning gas is selected to remove residues that are formed during the first cleaning step.  
     
     
         3 . A method according to  claim 1  wherein in the first chlorine-containing gas comprises only chlorine, and wherein the second chlorine-containing gas comprises chlorine and hydrogen.  
     
     
         4 . A method according to  claim 1  wherein the second chlorine-containing gas comprises HCl.  
     
     
         5 . A method according to  claim 4  wherein the second energized cleaning gas comprises HCl and O 2  in a volumetric flow ratio of at least about 3:7.  
     
     
         6 . A method according to  claim 1  wherein at least one of the first and second cleaning gases comprises one or more of H 2 , H 2 O and H 2 O 2 .  
     
     
         7 . A substrate processing apparatus comprising: 
 a chamber having a substrate support;    a gas supply;    a gas energizer;    a gas exhaust; and    a controller comprising:    (a) substrate processing program code to operate the substrate support, gas supply, gas energizer and gas exhaust to process a substrate in the chamber by introducing an etchant gas into the chamber, energizing the etchant gas to etch the substrate, and exhausting the etchant gas; and    (b) chamber cleaning program code to operate the substrate support, gas supply, gas energizer and gas exhaust to clean surfaces in the chamber by, 
 (i) in a first cleaning step: 
 providing a first energized cleaning gas in the chamber, the first energized cleaning gas comprising a first chlorine-containing gas and oxygen; and  
 exhausting the first cleaning gas; and  
 
 (ii) in a second cleaning step: 
 providing a second energized cleaning gas in the chamber, the second energized cleaning gas comprising a second chlorine-containing gas and oxygen; and  
 exhausting the second cleaning gas.  
 
   
     
     
         8 . An apparatus according to  claim 7  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide a second energized cleaning gas that is selected to remove residues that are formed during the first cleaning step.  
     
     
         9 . An apparatus according to  claim 7  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide a first chlorine-containing gas comprising only chlorine in the first cleaning step, and a second chlorine-containing gas comprising chlorine and hydrogen in the second cleaning step.  
     
     
         10 . An apparatus according to  claim 7  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide a second chlorine-containing gas comprising HCl.  
     
     
         11 . An apparatus according to  claim 10  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide a second energized cleaning gas comprising HCl and O 2  in a volumetric flow ratio of at least about 3:7.  
     
     
         12 . An apparatus according to  claim 7  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide at least one of a first and second cleaning gas comprising one or more of H 2 , H 2 O and H 2 O 2 .  
     
     
         13 . A method of cleaning process residues formed on surfaces in a chamber during processing of a substrate in the chamber, the method comprising: 
 (a) a first cleaning step comprising; 
 introducing a first cleaning gas into the chamber, the first cleaning gas comprising Cl 2  and O 2 ;  
 coupling RF energy to the first cleaning gas in the chamber to energize the first cleaning gas; and  
 exhausting the first cleaning gas; and  
   (b) a second cleaning step comprising: 
 introducing a second cleaning gas into the chamber, the second cleaning gas comprising HCl and O 2 ;  
 coupling RF energy to the second cleaning gas in the chamber to energize the second cleaning gas; and  
 exhausting the second cleaning gas.  
   
     
     
         14 . A method according to  claim 13  wherein the second cleaning gas comprises HCl and O 2  in a volumetric flow ratio of at least about 3:7.  
     
     
         15 . A method according to  claim 13  further comprising, before (a) or (b), introducing a purging gas into the chamber, sustaining a plasma of the purging gas, and exhausting the purging gas.  
     
     
         16 . A substrate processing apparatus comprising: 
 a chamber having a substrate support;    a gas supply;    a gas energizer;    a gas exhaust; and    a controller comprising:    (a) substrate processing program code to operate the substrate support, gas supply, gas energizer and gas exhaust to process a substrate in the chamber by introducing an etchant gas into the chamber, energizing the etchant gas to etch the substrate, and exhausting the etchant gas; and    (b) chamber cleaning program code to operate the substrate support, gas supply, gas energizer and gas exhaust to clean surfaces in the chamber by, 
 (i) in a first cleaning step: 
 introducing a first cleaning gas into the chamber, the first cleaning gas comprising Cl 2  and O 2 ;  
 coupling RF energy to the first cleaning gas in the chamber to energize the first cleaning gas; and  
 exhausting the first cleaning gas; and  
 
 (ii) in a second cleaning step: 
 introducing a second cleaning gas into the chamber, the second cleaning gas comprising HCl and O 2 ;  
 coupling RF energy to the second cleaning gas in the chamber to energize the second cleaning gas; and  
 exhausting the second cleaning gas.  
 
   
     
     
         17 . An apparatus according to  claim 16  wherein the controller further comprises chamber purging program code to operate the substrate support, gas supply, gas energizer and gas exhaust to purge the chamber by introducing a purge gas into the chamber, sustaining a plasma of the purging gas, and exhausting the purge gas.  
     
     
         18 . An apparatus according to  claim 17  wherein the controller comprises chamber purging program code to operate the gas supply to introduce the purge gas before and after the first and second cleaning steps.  
     
     
         19 . An apparatus according to  claim 16  wherein the controller comprises chamber cleaning program code to operate the gas supply to introduce a second cleaning gas comprising HCl and O 2  in a volumetric flow ratio of at least about 3:7.  
     
     
         20 . A method of cleaning process residues formed on surfaces in a chamber during processing of a substrate in the chamber, the method comprising: 
 (a) providing an energized cleaning gas in the chamber, the energized cleaning gas comprising H 2 , chlorine species and oxygen species; and    (b) exhausting the cleaning gas.    
     
     
         21 . A method according to  claim 20  wherein the cleaning gas comprises one or more of HCl and Cl 2 .  
     
     
         22 . A method according to  claim 20  wherein the cleaning gas comprises one or more of O 2 , H 2 O and H 2 O 2 .  
     
     
         23 . A method according to  claim 20  further comprising: 
 (c) providing a second energized cleaning gas in the chamber, the second energized cleaning gas comprising Cl 2  and O 2 ; and 
 exhausting the second cleaning gas.  
 
 
     
     
         24 . A substrate processing apparatus comprising: 
 a chamber having a substrate support;    a gas supply;    a gas energizer;    a gas exhaust; and    a controller comprising:    (a) substrate processing program code to operate the substrate support, gas supply, gas energizer and gas exhaust to process a substrate in the chamber by introducing an etchant gas into the chamber, energizing the etchant gas to etch the substrate, and exhausting the etchant gas; and    (b) chamber cleaning program code to operate the substrate support, gas supply, gas energizer and gas exhaust to clean surfaces in the chamber by, 
 (i) providing an energized cleaning gas in the chamber, the first energized cleaning gas comprising H 2 , chlorine species and oxygen species; and  
 (ii) exhausting the cleaning gas.  
   
     
     
         25 . An apparatus according to  claim 24  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide one or more of HCl and Cl 2 .  
     
     
         26 . An apparatus according to  claim 24  wherein the controller comprises chamber cleaning program code to operate the gas supply to provide one or more of O 2 , H 2 O and H 2 O 2 .  
     
     
         27 . An apparatus according to  claim 24  wherein the controller comprises chamber cleaning program code to operate the substrate support, gas supply, gas energizer and gas exhaust to clean surfaces in the chamber by, in a second cleaning step: 
 (iii) providing a second energized cleaning gas in the chamber, the second energized cleaning gas comprising Cl 2  and O 2 ; and  
 (iv) exhausting the second cleaning gas.