Plasma processing method

Abstract

The present invention is a plasma processing method including: a step of introducing a substrate into a processing container, a metal or metallic compound film being formed on a surface of the substrate; a step of supplying a noble gas and an H 2 gas into the processing container; and a step of generating plasma in the processing container while the noble gas and the H 2 gas are supplied, so that a natural oxide film formed on a surface of the metal or metallic compound film is removed by means of the plasma. According to the invention, the noble gas and the H 2 gas are supplied into the processing container, the plasma is generated in the processing container, and the plasma acts on the natural oxide film formed on a surface of the metal or metallic compound film. Thus, active hydrogen in the plasma reduces the natural oxide film, and active species of the noble gas etch the natural oxide film. As a result, the natural oxide film can be removed with a satisfactory selective ratio.

1 - 37 . (canceled)  
   
   
       38 . A plasma processing method comprising; 
 a step of introducing a substrate into a processing container, a metal or metallic compound or Si film being on a surface of the substrate,    a step of supplying an Ar gas into the processing container, and    a step of generating inductive coupling plasma in the processing container while the Ar gas is supplied, so that a natural oxide film existing on a surface of the metal or metallic compound or Si film is removed by means of the plasma, wherein    a gas flow rate of the Ar gas is 30 sccm or lower,    an etching selective ratio of the natural oxide film with respect to the metal or metallic compound or Si film is 3 or more,    a frequency for generating the inductive coupling plasma is 450 kHz, and    a frequency of the high-frequency bias voltage is 13.56 MHz.    
   
   
       39 . A plasma processing method according to  claim 38 , further comprising: 
 a step of heating the substrate to 200 to 500° C., after the step of supplying an Ar gas into the processing container.    
   
   
       40 . A plasma processing method according to  claim 38 , wherein the metal or metallic compound consists of any of CoSi 2 , Co, W, WSi, Cu, Al, Mo, MoSi, Ni and NiSi.  
   
   
       41 . A plasma processing method comprising: 
 a step of introducing a substrate into a processing container, a CoSi 2  film being on a surface of the substrate,    a step of supplying an Ar gas into the processing container, and    a step of heating the substrate to 200 to 500° C.,    a step of generating inductive coupling plasma in the processing container and applying a high-frequency bias voltage to the substrate while the Ar gas is supplied, so that a natural oxide film existing on a surface of the CoSi 2  film is removed by means of the plasma, wherein    a gas flow rate of the Ar gas is 30 sccm or lower,    an etching selective ratio of the natural oxide film with respect to the CoSi 2  film is 3 or more,    a frequency for generating the inductive coupling plasma is 450 kHz, and    a frequency of the high-frequency bias voltage is 13.56 MHz.    
   
   
       42 . A plasma processing method according to  claim 38 , wherein the high-frequency bias voltage to the substrate is 20 to 700 W.  
   
   
       43 . A plasma processing method according to  claim 41 , wherein the high-frequency bias voltage to the substrate is 20 to 700 W.  
   
   
       44 . A plasma processing method according to  claim 38 , wherein the high-frequency bias voltage to the substrate is 10 to 500 W.  
   
   
       45 . A plasma processing method according to  claim 41 , wherein the high-frequency bias voltage to the substrate is 10 to 500 W.  
   
   
       46 . A plasma processing method according to  claim 38 , wherein a pressure in the processing container is 0.133 to 6.55 Pa.  
   
   
       47 . A plasma processing method according to  claim 41 , wherein a pressure in the processing container is 0.133 to 6.55 Pa.  
   
   
       48 . A plasma processing method according to  claim 38 , wherein a pressure in the processing container is 0.133 to 2.66 Pa.  
   
   
       49 . A plasma processing method according to  claim 41 , wherein a pressure in the processing container is 0.133 to 2.66 Pa.  
   
   
       50 . A plasma processing method according to  claim 38 , wherein the time of the step of removing the natural oxide film is 10 to 180 seconds.  
   
   
       51 . A plasma processing method according to  claim 41 , wherein the time of the step of removing the natural oxide film is 10 to 180 seconds.  
   
   
       52 . A plasma processing method according to  claim 38 , wherein the time of the step of removing the natural oxide film is 10 to 120 seconds.  
   
   
       53 . A plasma processing method according to  claim 41 , wherein the time of the step of removing the natural oxide film is 10 to 120 seconds.  
   
   
       54 . A plasma processing method according to  claim 38 , further comprising: 
 a step of covering an edge of the substrate by means of a circular member, after the step of supplying an Ar gas into the processing container.    
   
   
       55 . A plasma processing method according to  claim 41 , further comprising: 
 a step of covering an edge of the substrate by means of a circular member, after the step of supplying an Ar gas into the processing container.    
   
   
       56 . A plasma processing method according to  claim 38 , wherein 
 the processing container has a chamber whose upper end is open and a bell jar is arranged on the chamber,    an inductive coil is wound around an outside periphery of the bell jar,    a susceptor for placing the substrate thereon is arranged in the processing container,    a lower electrode is buried in the susceptor, and    the chamber is connected to an exhaust unit.    
   
   
       57 . A plasma processing method according to  claim 41 , wherein 
 the processing container has a chamber whose upper end is open and a bell jar is arranged on the chamber,    an inductive coil is wound around an outside periphery of the bell jar,    a susceptor for placing the substrate thereon is arranged in the processing container,    a lower electrode is buried in the susceptor, and    the chamber is connected to an exhaust unit.    
   
   
       58 . A plasma processing method comprising: 
 a step of introducing a substrate into a processing container, a metal or metallic compound or Si film being on a surface of the substrate,    a step of supplying an Ar gas into the processing container,    a step of generating inductive coupling plasma in the processing container while the Ar gas is supplied, so that a natural oxide film existing on a surface of the metal or metallic compound or Si film is removed by means of the plasma,    a step of forming a Ti film on the substrate, and    a step of forming a TiN film on the Ti film, wherein    a gas flow rate of the Ar gas is 30 sccm or lower,    an etching selective ratio of the natural oxide film with respect to the metal or metallic compound or Si film is 3 or more,    a frequency for generating the inductive coupling plasma is 450 kHz, and    a frequency of the high-frequency bias voltage is 13.56 MHz.    
   
   
       59 . A plasma processing method according to  claim 58 , wherein 
 the step of forming a Ti film is conducted by a plasma CVD process using a TiCl 4  gas, an H 2  gas and an Ar gas.    
   
   
       60 . A plasma processing method according to  claim 58 , wherein 
 the step of forming a TiN film is conducted by a CVD process using a gas including a TiCl 4  gas and an NH 3  gas.    
   
   
       61 . A plasma processing method according to  claim 59 , wherein 
 the step of forming a TiN film is conducted by a CVD process using a gas including a TiCl 4  gas and an NH 3  gas.