Plasma processing apparatus and method with controlled biasing functions

Abstract

A plasma processing apparatus including: a phase controller for controlling a phase difference between biasing power supplied to the antenna biasing electrode and biasing power supplied to the substrate electrode to have a difference of 180°±45°; wherein the biasing power supplied to the antenna biasing electrode and the biasing power supplied to the substrate electrode have a same frequency, which same frequency is lower than a frequency of the RF power for plasma generation. A plurality of filters is included, to perform a variety of filtering.

1 . A plasma processing apparatus comprising:
 a container of which the inside is controlled to have a predetermined pressure-reduced atmosphere;   a substrate electrode on which a sample to be processed provided in said container can be placed;   an antenna electrode provided to oppose said substrate electrode;   a plasma-generating RF power supply connected via a first filter and a first matching circuit to said antenna electrode to supply an R.F power thereto, for generating plasma within said container;   an antenna biasing power supply connected via a second filter and a second matching circuit to said antenna electrode;   a substrate biasing power supply connected via a third filter and a third matching circuit to said substrate electrode;   a phase controller for controlling a phase difference between biasing power supplied to said antenna biasing electrode and biasing power supplied to said substrate electrode to have a difference of 180°±45′;   wherein said biasing power supplied to the antenna biasing electrode and said biasing power supplied to the substrate electrode have a same frequency, which same frequency is lower than a frequency of said RF power for plasma generation;   wherein said first filter operates to pass RF power from said plasma-generating RF power supply, but cut out RF biasing power from said antenna biasing power supply;   wherein said second filter operates to pass biasing power from said antenna biasing power supply, but cut out RF biasing power from said plasma-generating RF power supply;   wherein said third filter operates to pass biasing power from said substrate biasing power supply, but cut out RF power from said plasma-generating RF power supply;   wherein said phase controller operates to extract voltage waveforms from said second filter and said second matching circuit and from said third filter and said third matching circuit, respectively;   wherein said phase controller controls the phase differences of the respective voltage waveforms within 180°±45°, and signals with a small amplitude and a phase difference to each other are output to said antenna biasing electrode and said substrate biasing electrode.   
   
   
       2 . A plasma processing apparatus according to  claim 1 , comprising a magnetic generating coil for generating a magnetic flux passing through said antenna electrode and said substrate electrode.