Plasma processing apparatus and control method thereof

Abstract

There is provided a plasma processing apparatus includes a lower electrode in a processing chamber on which a object to be processed is mounted; an upper electrode confronting the lower electrode; a first and a second high-frequency power supply for applying high-frequency powers respectively to the upper and the lower electrode; and an output controller for raising each of outputs from the high-frequency power supplies at least three times in a stepwise manner up to each of set levels for processing the object to be processed. The output controller adjusts each of rising times of the outputs from the high-frequency power supplies so that an output of the second high-frequency power supply is raised earlier than an output of the first high-frequency power supply while the outputs from the high-frequency power supplies are raised up to the set levels in a stepwise manner.

1 - 24 . (canceled) 
   
   
       25 . A plasma processing apparatus, comprising:
 a lower electrode disposed in a processing chamber, capable of mounting an object to be processed thereon;   an upper electrode disposed in the chamber to face the lower electrode;   a first high-frequency power supply and a second high-frequency power supply for applying high-frequency powers to at least one of the upper and the lower electrode; and   an output controller for raising respective outputs of the first and the second high-frequency power supply up to respective set levels for processing the object to be processed,   wherein the output controller controls the respective outputs of the high-frequency power supplies to be raised continuously, to be raised stepwise, or to be raised stepwise during a certain interval and continuously during the rest, and   wherein the output controller regulates raise timings of the outputs of the respective high-frequency power supplies such that one of the high-frequency powers, whose frequency is lower than that of the other of the high-frequency powers, is raised earlier than the other of the high-frequency powers, while the outputs of the high-frequency power supplies are raised up to the respective set levels.   
   
   
       26 . The plasma processing apparatus of  claim 25 , wherein the output controller controls the respective outputs of the high-frequency power supplies such that the high frequency powers are raised stepwise in at least three steps, and one of the high-frequency powers reaches a level of a first step after the other of the high-frequency powers reaches a level of a first step but before the other of the high-frequency powers reaches a level of a second step, and
 wherein an output of the first high-frequency power supply has a frequency higher than that of an output of the second high-frequency power supply.   
   
   
       27 . The plasma processing apparatus of  claim 26 , wherein the output of the first high-frequency power supply is supplied to the upper electrode, and the output of the second high-frequency power supply is supplied to the lower electrode. 
   
   
       28 . The plasma processing apparatus of  claim 27 , wherein the output controller regulates the outputs of the respective high-frequency power supplies so that the outputs right before reaching the respective set levels are within 25% and 50% of the set levels. 
   
   
       29 . The plasma processing apparatus of  claim 28 , wherein the output controller regulates the outputs of the respective high-frequency power supplies so that first outputs are equal to or above levels at which plasma can be ignited and not more than 25% of the respective set levels. 
   
   
       30 . The plasma processing apparatus of  claim 27 , wherein the output controller regulates the outputs of the respective high-frequency power supplies so that, while keeping the output of one high-frequency power supply constant, the output of the other high-frequency power supply is raised. 
   
   
       31 . The plasma processing apparatus of  claim 27 , wherein the output controller regulates the outputs of the respective high-frequency power supplies so that differences between the respective outputs fall within a certain range. 
   
   
       32 . The plasma processing apparatus of  claim 25 , wherein one of the high-frequency powers is applied to the lower electrode whereas the other of the high-frequency powers is applied to the upper electrode, and
 wherein the output controller controls the high-frequency powers such that one of the high-frequency powers applied to the lower electrode reaches a set level earlier than the other of the high-frequency powers applied to the upper electrode.   
   
   
       33 . A method for controlling a plasma processing apparatus including a lower electrode in a processing chamber on which an object to be processed is mounted, an upper electrode disposed in the chamber to face the lower electrode, and a first high-frequency power supply and a second high-frequency power supply for applying high-frequency powers to at least one of the upper and the lower electrode, the method comprising the step of:
 raising respective outputs of the high-frequency power supplies to reach respective set levels for processing the object to be processed,   wherein the respective outputs of the high-frequency power supplies are controlled to be raised continuously, to be raised stepwise, or to be raised stepwise during a certain interval and continuously during the rest, and   wherein respective raise timings of the outputs of the high-frequency power supplies are controlled such that one of the high-frequency powers, whose frequency is lower than that of the other of the high-frequency powers, is raised earlier than the other of the high-frequency powers, while the respective outputs of the high-frequency power supplies are raised to the respective set levels.   
   
   
       34 . The method of  claim 33 , wherein the respective outputs of the high-frequency power supplies are controlled such that the high-frequency powers are raised stepwise in at least three steps, and one of the high-frequency powers reaches a level of a first step after the other of the high-frequency powers reaches a level of a first step but before the other of the high-frequency powers reaches a level of a second step, and
 wherein an output of the first high-frequency power supply has a frequency higher than that of an output of the second high-frequency power supply.   
   
   
       35 . The method of  claim 34 , wherein the output of the first high-frequency power supply is supplied to the upper electrode, and the output of the second high-frequency power supply is supplied to the lower electrode. 
   
   
       36 . The method of  claim 35 , wherein the respective outputs of the high-frequency power supplies are regulated so that the outputs right before reaching the respective set levels are within 25% and 50% of the set levels. 
   
   
       37 . The method of  claim 36 , wherein the outputs of the respective high-frequency power supplies are regulated so that first outputs are equal to or above levels at which plasma can be ignited and not more than 25% of the respective set levels. 
   
   
       38 . The method of  claim 35 , wherein the outputs of the respective high-frequency power supplies are regulated so that, while keeping the output of one high-frequency power supply constant, the output of the other high-frequency power supply is raised. 
   
   
       39 . The method of  claim 35 , wherein the outputs of the respective high-frequency power supplies are regulated so that differences between the respective outputs fall within a certain range. 
   
   
       40 . The method of  claim 33 , wherein one of the high-frequency powers is applied to the lower electrode whereas the other of the high-frequency powers is applied to the upper electrode, and
 wherein the high-frequency powers are controlled such that one of the high-frequency powers applied to the lower electrode reaches a set level earlier than the other of the high-frequency powers applied to the upper electrode.