Semiconductor processing with a remote plasma source for self-cleaning

Abstract

A plasma CVD device includes a reaction chamber, a remote plasma discharge chamber that is provided remotely from the reaction chamber, and piping that links the reaction chamber and the remote plasma discharge chamber. The remote plasma discharge chamber activates cleaning gas by plasma discharge energy, and the activated cleaning gas is introduced into the inside of the reaction chamber through the piping and changes solid substances that adhere to the inside of the reaction chamber in consequence of film formation, to gaseous substances, thereby cleaning the inside of the reaction chamber. The device is characterized by at least one of the following: (a) the remote plasma discharge chamber generates active species using radio frequency oscillating output energy of a preselected frequency; (b) the piping is made of materials that are not corroded by the active species; or (c) the piping is provided with a through-flow type valve.

1 . A method of cleaning a chemical vapor deposition (CVD) reaction chamber with cleaning gas provided through a remote plasma discharge chamber, comprising: 
 dissociating cleaning gas within the remote plasma discharge chamber, wherein said dissociated cleaning gas is exposed to an anodized aluminum alloy wall of the remote plasma discharge chamber;    supplying activated species from the remote plasma discharge chamber to the reaction chamber through a piping;    opening a valve on the piping after conducting a CVD reaction and prior to supplying activated species, wherein opening a valve comprises withdrawing a valve body completely from a path to form an opening substantially as wide as internal surfaces of the piping; and    removing adhered deposits from CVD reactions on a wall of the reaction chamber.    
   
   
       2 . The method of  claim 1 , further comprising closing the valve after removing the adhered deposits.  
   
   
       3 . The method of  claim 1 , wherein removing adhered deposits comprises removing adhered silicon nitride deposits.  
   
   
       4 . The method of  claim 1 , wherein the cleaning gas comprises fluorine-containing gas and the activated species comprises fluorine active species.  
   
   
       5 . The method of  claim 1 , wherein the applied energy has a frequency between about 300 kHz and 500 kHz.  
   
   
       6 . The method of  claim 1 , wherein supplying activated species comprises flowing NF 3  through the remote plasma discharge chamber at a rate between about 0.5 slm and 1.5 slm.  
   
   
       7 . The method of  claim 1 , wherein supplying activated species comprises flowing the activated species solely along a straight-line section of the piping.  
   
   
       8 . The method of  claim 1 , wherein when cleaning gas flows from the remote plasma discharge chamber to the reaction chamber, no appreciable pressure loss arises in the piping and at the valve.  
   
   
       9 . The method of  claim 8 , wherein dissociating cleaning gas comprises applying an energy in the remote plasma discharge chamber of less than 3000 W to the cleaning gas to form the activated species, wherein said activated species is a fluorine species; and wherein removing the adhered deposits from CVD reactions on a wall of the reaction chamber occurs at a rate of greater than or equal to about 2.0 microns/minute.  
   
   
       10 . The method of  claim 9 , wherein removing adhered deposits on the wall of the reaction chamber comprises removing adhered silicon nitride deposits.  
   
   
       11 . The method of  claim 9 , wherein removing adhered deposits on the wall of the reaction chamber comprises removing adhered silicon oxide deposits.  
   
   
       12 . The method of  claim 9 , wherein removing adhered deposits on the wall of the reaction chamber comprises removing adhered tungsten deposits.  
   
   
       13 . The method of  claim 9 , the cleaning gas comprises carbon tetrafluoride (CF 4 ).  
   
   
       14 . The method of  claim 9 , the cleaning gas comprises nitrogen trifluoride (NF 3 ).  
   
   
       15 . The method of  claim 9 , wherein dissociating cleaning gas comprises applying an energy of between about 2,500 W and 3,000 W.  
   
   
       16 . The method of  claim 15 , wherein the applied energy has a frequency between about 300 kHz and 500 kHz.  
   
   
       17 . A method of cleaning a chemical vapor deposition (CVD) reaction chamber with cleaning gas provided through a remote plasma discharge chamber, comprising: 
 dissociating cleaning gas within the remote plasma discharge chamber, wherein said dissociated cleaning gas is exposed to an anodized aluminum alloy wall of the remote plasma discharge chamber;    supplying activated species from the remote plasma discharge chamber to the reaction chamber through a piping, wherein said piping is a straight-line structure between the remote plasma discharge chamber and the chemical vapor deposition reaction chamber;    opening a valve on the piping after conducting a CVD reaction and prior to supplying activated species, wherein opening a valve comprises withdrawing a valve body completely from a path to form an opening substantially as wide as internal surfaces of the piping, wherein when cleaning gas flows from the remote plasma discharge chamber to the reaction chamber, no appreciable pressure loss arises in the piping and at the valve; and    removing adhered deposits from CVD reactions on a wall of the reaction chamber.    
   
   
       18 . A method of cleaning a chemical vapor deposition (CVD) reaction chamber with cleaning gas provided through a remote plasma discharge chamber, comprising: 
 dissociating cleaning gas within the remote plasma discharge chamber, wherein said dissociated cleaning gas is exposed to an anodized aluminum alloy wall of the remote plasma discharge chamber;    supplying activated species from the remote plasma discharge chamber to the CVD reaction chamber, wherein the activated species flows rectilinearly from the remote plasma discharge chamber to the CVD reaction chamber in a piping;    opening a valve on the piping after conducting a CVD reaction and prior to supplying activated species, wherein opening a valve comprises withdrawing a valve body completely from a path to form an opening substantially as wide as internal surfaces of the piping, wherein when cleaning gas flows from the remote plasma discharge chamber to the reaction chamber, no appreciable pressure loss arises in the piping and at the valve; and    removing adhered deposits from CVD reactions on a wall of the reaction chamber.    
   
   
       19 . The method of  claim 18 , wherein supplying activated species comprises flowing through rectilinear piping having more than one inch in diameter.