Plasma treating method and apparatus therefor

A plasma treating apparatus comprising:

• means for rendering a gas having a critical potential plasmic under a reduced pressure by use of the action of an electric field by microwaves and the action of a magnetic field by magnetic field generation means, said critical potential being a potential at which an etching action and a deposition action are in equilibrium with each other when a sample is treated with the plasma which is generated by rendering a certain kind of gas plasmic under a predetermined plasma condition and applying an acceleration voltage to ions in said plasma so as to let thm be incident to said sample;
• means for applying said acceleration voltage to a sample table on which said sample is placed;
• and
• means for changing said acceleration voltage interposing said critical potential.

A plasma treating apparatus comprising:

• a vacuum treating vessel having a discharge tube disposed at an upper opening thereof;
• a discharge space within said discharge tube;
• a waveguide disposed so as to encircle said discharge tube, said waveguide including a magnetron for generating microwaves;
• an electromagnetic coil disposed around the outer periphery of said discharge tube through said waveguide;
• an electrode including a sample table disposed within said vacuum treating vessel so as to allow support of a sample to be treated in said discharge space;
• a ground electrode disposed around the outer periphery of said electrode and electrically insulated therefrom;
• means to introduce gas into said discharge space, said gas having a critical potential at which an etching action and a deposition action of said gas are in equilibrium;
• and
• means to control an acceleration voltage connected to said electrode, for accelerating ions in a plasma of said gas, so as to alternately etch and deposit said sample.

A plasma treating apparatus comprising:

• a vacuum treating vessel having a discharge tube disposed at an upper opening thereof;
• a discharge space within said discharge tube;
• a waveguide disposed so as to encircle said discharge tube, said waveguide including a magnetron for generating microwaves;
• an electromagnetic coil disposed around the outer periphery of said discharge tube through said waveguide;
• an electrode including a sample table disposed within said vacuum treating vessel so as to allow support of a sample to be treated in said discharge space;
• means to introduce gas into said discharge space, said gas having a critical potential at which at etching action and a deposition action of said gas are in equilibrium;
• means to control an acceleration voltage for accelerating ions in a plasma of said gas, so as to alternately etch and deposit said sample;
• said means to control acceleration voltage including a grid electrode disposed in said discharge space above said sample, D.C. power source connected to said grid electrode, an output voltage controller connected to said D.C. power source, and an output waveform controller connected to said output voltage controller.

A plasma treating apparatus comprising:

• a vacuum treating vessel having a gas injection port;
• an upper electrode disposed in an upper portion of said vacuum treating vessel;
• a lower electrode for supporting a sample to be treated, disposed in a lower portion of said vacuum treating vessel so as to face said upper electrode, said lower electrode being insulated from said vacuum treating vessel;
• means to introduce gas into said vacuum treating vessel through said injection port, said gas having a critical potential at which an etching action and a deposition action of said gas are in equilibrium;
• and
• means to control an acceleration voltage connected to said lower electrode for accelerating ions in a plasma of said gas, so as to alternately etch and deposit said sample.

A plasma treating apparatus comprising:

• a vacuum treating vessel having a gas injection port;
• an upper electrode disposed in an upper portion of said vacuum treating vessel;
• a lower electrode for supporting a sample to be treated, disposed in a lower portion of said vacuum treating vessel so as to face said upper electrode, said lower electrode being insulated from said vacuum treating vessel;
• means to introduce gas into said vacuum treating vessel through said injection port, said gas having a critical potential at which an etching action and a deposition action of said gas are in equilibrium;
• and
• means to control an acceleration voltage for accelerating ions in a plasma of said gas, so as to alternately etch and deposit said sample, said means to control an acceleration voltage including a grid electrode disposed in said vacuum treating vessel above said sample, a D.C. power source connected to said grid electrode, an output voltage controller connected to said D.C. power source, an output waveform controller connected to said output voltage controller, and a radio frequency power source connected to said lower electrode through a matching box.