Plasma processing apparatus

Abstract

A plasma processing apparatus includes a pedestal to receive a substrate thereon; a temperature control mechanism provided in the pedestal; a heat transfer gas supply mechanism configured to supply a heat transfer gas to a back surface of the substrate; a first radio frequency power source configured to output first high frequency power having a first frequency; a second radio frequency power source configured to output second high frequency power having a second frequency that is lower than the first frequency; and a temperature measurement unit configured to control a surface temperature of the substrate to have a temperature lower than −35 degrees C. by using the temperature control mechanism provided in the pedestal and to perform feedback control of stopping the output of the second radio frequency power from the second radio frequency power source.

What is claimed is: 
     
         1 . A plasma processing apparatus, comprising:
 a pedestal to receive a substrate thereon;   a temperature control mechanism provided in the pedestal;   a heat transfer gas supply mechanism configured to supply a heat transfer gas to a back surface of the substrate;   a first radio frequency power source configured to output first high frequency power having a first frequency;   a second radio frequency power source configured to output second high frequency power having a second frequency that is lower than the first frequency; and   a temperature measurement unit configured to control a surface temperature of the substrate to have a temperature lower than −35 degrees C. by using the temperature control mechanism provided in the pedestal and to perform feedback control of stopping the output of the second radio frequency power from the second radio frequency power source.   
     
     
         2 . The plasma processing apparatus as claimed in  claim 1 , wherein both of the first radio frequency power and the second radio frequency power have pulse waves or the second radio frequency power has pulse waves. 
     
     
         3 . The plasma processing apparatus as claimed in  claim 1 , wherein the stop of the output of the second radio frequency power from the second radio frequency power source, and pressure control of the heat transfer gas, are performed by autonomous control. 
     
     
         4 . The plasma processing apparatus as claimed in  claim 1 , further comprising:
 a monitor mechanism configured to monitor the surface temperature of the substrate in real time.   
     
     
         5 . The plasma processing apparatus as claimed in  claim 4 , further comprising:
 a focus ring provided on a periphery of the pedestal,   wherein the monitor mechanism is configured to monitor the surface temperature of the substrate based on a result of temperature measurement of the focus ring.   
     
     
         6 . The plasma processing apparatus as claimed in  claim 5 , wherein the temperature measurement unit measures the surface temperature of the substrate by using an interferometer type thermometer. 
     
     
         7 . The plasma processing apparatus as claimed in  claim 1 , further comprising:
 a focus ring provided on a periphery of the pedestal,   wherein the temperature measurement unit performs the feedback control so that the focus ring has a temperature lower than −35 degrees C. by stopping the output of the second radio frequency power from the second radio frequency power source.   
     
     
         8 . A plasma processing apparatus, comprising:
 a pedestal to receive a substrate thereon;   a temperature control mechanism provided in the pedestal;   a heat transfer gas supply mechanism configured to supply a heat transfer gas to a back surface of the substrate;   a first radio frequency power source configured to output first high frequency power having a first frequency;   a second radio frequency power source configured to output second high frequency power having a second frequency that is lower than the first frequency; and   a temperature measurement unit configured to control a surface temperature of the substrate to have a temperature lower than −35 degrees C. by using the temperature control mechanism provided in the pedestal and to perform feedback control of stopping the output of the first radio frequency power from the first radio frequency power source and the output of the second radio frequency power from the second radio frequency power source.   
     
     
         9 . The plasma processing apparatus as claimed in  claim 8 , wherein both of the first radio frequency power and the second radio frequency power have pulse waves or the second radio frequency power has pulse waves. 
     
     
         10 . The plasma processing apparatus as claimed in  claim 8 , wherein the stop of at least one of the output of the first radio frequency power from the first radio frequency power source and the output of the second radio frequency power from the second radio frequency power source, and pressure control of the heat transfer gas, are performed by autonomous control. 
     
     
         11 . The plasma processing apparatus as claimed in  claim 8 , further comprising:
 a monitor mechanism configured to monitor the surface temperature of the substrate in real time.   
     
     
         12 . The plasma processing apparatus as claimed in  claim 11 , further comprising:
 a focus ring provided on a periphery of the pedestal,   wherein the monitor mechanism is configured to monitor the surface temperature of the substrate based on a result of temperature measurement of the focus ring.   
     
     
         13 . The plasma processing apparatus as claimed in  claim 12 , wherein the temperature measurement unit measures the surface temperature of the substrate by using an interferometer type thermometer. 
     
     
         14 . The plasma processing apparatus as claimed in  claim 1 , further comprising:
 a focus ring provided on a periphery of the pedestal,   wherein the temperature measurement unit performs the feedback control so that the focus ring has a temperature lower than −35 degrees C. by stopping the output of the first radio frequency power from the first radio frequency power source and the output of the second radio frequency power from the second radio frequency power source.