Plasma processing apparatus

Abstract

A plasma processing apparatus including a vacuum vessel, a lower electrode provided in the vacuum vessel to place a sample thereon, a matcher connected to the lower electrode, and a power supply for supplying power to the lower electrode via the matcher includes an electrostatic chuck electrode provided within the lower electrode to hold the sample, and a voltage measurement circuit provided within the lower electrode to measure a voltage at the electrostatic chuck electrode and output the measured voltage as a DC voltage.

1 . A plasma processing apparatus including a vacuum vessel, a lower electrode provided in the vacuum vessel to place a sample thereon, a matcher connected to the lower electrode, and a power supply for supplying power to the lower electrode via the matcher, the plasma processing apparatus comprising:
 an electrostatic chuck electrode provided within the lower electrode to hold the sample; and   a voltage measurement circuit provided within the lower electrode to measure a voltage at said electrostatic chuck electrode and output the measured voltage as a DC voltage.   
   
   
       2 . The plasma processing apparatus according to  claim 1 , wherein said voltage measurement circuit is installed within a vessel that intercepts at least a corrosive gas. 
   
   
       3 . The plasma processing apparatus according to  claim 1 , wherein said voltage measurement circuit can detect a phase signal. 
   
   
       4 . A plasma processing apparatus including a vacuum vessel, a lower electrode provided in the vacuum vessel so as to incorporate an electrostatic chuck electrode for holding a sample, a matcher connected to the lower electrode, and a power supply for supplying power to the lower electrode via the matcher, the plasma processing apparatus comprising:
 a voltage measurement circuit provided under atmospheric pressure to measure a voltage at the electrostatic chuck electrode and output the measured voltage as a DC voltage; and   a coaxial line for connecting the electrostatic chuck electrode to said voltage measurement circuit.   
   
   
       5 . The plasma processing apparatus according to  claim 4 , wherein a composite impedance of said voltage measurement circuit and said coaxial line is greater than a load impedance between the electrostatic chuck electrode and plasma. 
   
   
       6 . The plasma processing apparatus according to  claim 4 , wherein said voltage measurement circuit can detect a phase signal. 
   
   
       7 . A plasma processing apparatus including a vacuum vessel, a lower electrode provided in the vacuum vessel so as to incorporate an electrostatic chuck electrode for holding a sample, an upper electrode provided in a position opposed to the lower electrode, a first matcher connected to the lower electrode, a first power supply for supplying power to the lower electrode via the first matcher, a second matcher connected to the upper electrode, and a second power supply for supplying power to the upper electrode via the second matcher, the plasma processing apparatus comprising:
 a first phase measurement circuit provided under atmospheric pressure to measure a phase of a voltage applied to the electrostatic chuck electrode;   a first coaxial line for connecting the electrostatic chuck electrode to said first phase measurement circuit;   a second phase measurement circuit provided under atmospheric pressure to measure a phase of a voltage applied to the upper electrode;   a second coaxial line for connecting the upper electrode to said second phase measurement circuit; and   a controller for controlling the first power supply and the second power supply based on output signals of said first phase measurement circuit and said second phase measurement circuit.