Method and apparatus for generating highly dense uniform plasma by use of a high frequency rotating electric field

A plasma generating apparatus comprising electric field exciting means for exciting, in a plasma generating part in a vacuum chamber, a rotational electric field to cause electrons in said plasma generating part to present rotational motions, said electric field exciting means comprising:

• three or more lateral electrodes so disposed as to surround said plasma generating part;
• a high frequency power supply for supplying a first high frequency electric power to one of said three or more lateral electrodes;
• a sample stage at a lower part of said plasma generating part, said sample stage being supplied with a second high frequency electric power which is lower in frequency than said first high frequency electric power;
• and
• a delay circuit group comprising a plurality of delay circuits for respectively supplying, with a delay, to other lateral electrodes of said three or more lateral electrodes, high frequency electric powers which are received from said high frequency electric power supply, which have the same frequency identical with the frequency of said first-mentioned high frequency electric power and of which respective phases are successively different from the phase of said first-mentioned high frequency electric power.

A plasma generating method comprising the steps of:

• disposing three or more lateral electrodes at lateral sides of a plasma generating part in a vacuum chamber, such that said three or more lateral electrodes surround said plasma generating part, and further disposing a sample stage at a lower part of said plasma generating part;
• respectively supplying, to said three or more lateral electrodes, first high frequency electric power of a first frequency, said first frequency having phases which are successively different from one another and wherein said phase differences are substantially equal to one another;
• and
• supplying, to said sample stage, second high frequency electric power of a second frequency which is different from said first frequency.

A plasma generating apparatus, comprising:

• a sample stage disposed at a lower part of a plasma generating part in a vacuum chamber;
• and
• electric field exciting means for exciting, in said plasma generating part, a rotational electric field to cause electrons in said plasma generating part to present oscillating motions, said electric field exciting means comprising:
• three or more lateral electrodes surrounding said plasma generating part, and first high frequency power supply means for supplying, to each of said three or more lateral electrodes, first high frequency electric power of a first frequency, said first frequency having phases which are successively different from one another and wherein said phase differences are substantially equal to one another;
• and
• second high frequency power supply means for supplying, to said sample stage, second high frequency electric power of a second frequency which is different from said first frequency.

A plasma etching method comprising the steps of:

• disposing three or more lateral electrodes at lateral sides of a plasma generating part in a vacuum chamber, such that said three or more lateral electrodes surround said plasma generating part, and further disposing at a lower part of said plasma generating part a sample stage for receiving a substrate;
• respectively supplying, to said three or more lateral electrodes, first high frequency electric power of a first frequency, said first frequency having phases which are successively different from one another and wherein said phase differences are substantially equal to one another;
• supplying, to said sample stage, second high frequency electric power of a second frequency which is different from said first frequency;
• and
• etching a layer-to-be-etched of said substrate by introducing etching gas into said vacuum chamber.

A plasma chemical vapor deposition method comprising the steps of:

• disposing three or more lateral electrodes at lateral sides of a plasma generating part in a vacuum chamber, such that said three or more lateral electrodes surround said plasma generating part, and further disposing a sample stage at a lower part of said plasma generating part;
• respectfully supplying, to said three or more lateral electrodes, a first high frequency electric power of a same frequency, said frequency having phases which are successively different from one another and wherein said phase differences are substantially equal to one another;
• supplying, to said sample stage, a second high frequency electric power of a second frequency which is different from said first frequency, and
• forming a thin film on a surface of a substrate placed in said vacuum chamber by introducing reaction gas into said vacuum chamber.