Electron cyclotron resonance plasma source

An electron cyclotron resonance plasma source comprising:

• a plasma generating chamber into which gases are introduced and ionized into a plasma condition;
• a microwave source for applying microwave energy to the plasma generating chamber;
• an electromagnetic coil outside the plasma generating chamber for generating a magnetic flux density in the plasma generating chamber which in combination with the microwave energy causes an electron cyclotron resonance condition in the plasma generating chamber and ionizes the gases into a plasma comprising ions, electrons, free radicals, and neutral atoms;
• an extraction system for extracting an output from the plasma generating chamber;
• and
• a plurality of permanent magnets disposed at the periphery of the plasma generating chamber between the electromagnetic coil and the extraction system, wherein the permanent magnets are for enhancing the uniformity of the output.

An electron cyclotron resonance plasma source comprising:

• a plasma generating chamber at a high potential into which gases are introduced and ionized into a plasma condition;
• a microwave source at or near ground potential for applying microwave energy to the plasma generating chamber;
• a means for electrically isolating the plasma generating chamber from the microwave source through which the microwave energy passes to enter the plasma generating chamber;
• a magnetic field source outside the plasma generating chamber which in combination with the microwave energy causes an electron cyclotron resonance condition in the plasma generating chamber and ionizes the gases within the plasma generating chamber into a plasma comprising ions, electrons, free radicals, and neutral atoms;
• and
• an extraction system for extracting an output from the plasma generating chamber.

An electron cyclotron resonance plasma source comprising:

• a plasma generating chamber into which gases are introduced and ionized into a plasma condition;
• a microwave source for applying microwave energy to the plasma generating chamber;
• a water cooled window apparatus through which the microwave energy passes to enter the plasma generating chamber;
• a magnetic field source outside the plasma generating chamber for creating a magnetic flux density in the plasma generating chamber which in combination with the microwave energy causes an electron cyclotron resonance condition in the plasma generating chamber and ionizes the gases within the plasma generating chamber into a plasma comprising ions, electrons, free radicals, and neutral atoms;
• and
• an extraction system for extracting an output from the plasma generating chamber.

An electron cyclotron resonance plasma source comprising:

• a plasma generating chamber at vacuum pressure to which gases are introduced and ionized into a plasma condition;
• a microwave source at or near atmospheric pressure for applying Microwave energy to the plasma generating chamber;
• a means for pressure isolating the plasma generating chamber from the microwave source and through which the microwave energy passes to enter the plasma generating chamber;
• a magnetic field source outside the plasma generating chamber for creating a magnetic flux density in the plasma generating chamber which in combination with the microwave energy causes an electron cyclotron condition in the plasma generating chamber and ionizes the gases within the plasma generating chamber into a plasma comprising ions, electrons, free radicals, and neutral atoms;
• and
• an extraction system for extracting an output from the plasma generating chamber.

An electron cyclotron resonance plasma source comprising:

• a high voltage plasma generating chamber at vacuum pressure into which gases are introduced and ionized into a plasma condition;
• a grounded microwave source at or near atmospheric pressure for applying microwave energy to the plasma generating chamber;
• a window apparatus for providing electrical and pressure isolation of the plasma generating chamber from the microwave source and through which the microwave energy passes to enter the plasma generating chamber;
• a magnetic field source outside the plasma generating chamber for creating a magnetic flux density in the plasma generating chamber which in combination with the microwave energy causes an electron cyclotron resonance condition in the plasma generating chamber and ionizes the gases within the plasma generating chamber into a plasma comprising ions, electrons, and free radicals;
• and
• an extraction system for extracting an output from the plasma generating chamber;
• the window apparatus comprising:
• a first water cooled barrier in contact with the microwave circuitry having an opening through which the microwave energy passes and comprising a microwave choke;
• a second water cooled barrier in contact with the plasma generating chamber having an opening through which the microwave energy passes, wherein the first and second water cooled barriers are electrically isolated;
• a nonconductive window between the first and second barriers at the openings of the first and second barriers, wherein the window is cooled by conduction from the first and second water cooled barriers;
• a first metal vacuum seal between the first barrier and the window;
• and
• a second metal vacuum seal between the second barrier and the window.

A method of producing a uniform ion density in the output of an ECR plasma source, comprising the steps of

• introducing a gas into a plasma generating chamber;
• inducing cyclotron motion of electrons from the gas by a magnetic field of a first magnetic field source;
• ionizing the gas into a plasma by introducing a microwave beam into the plasma generating chamber which in combination with the magnetic field results in an electron cyclotron resonance condition;
• subjecting the plasma to a uniform magnetic field region within the plasma generating chamber to produce a uniform ion density of the plasma within the uniform magnetic field region;
• and outputting from the uniform plasma in the plasma generating chamber an output having a uniform ion density.

A method of producing a uniform ion beam output from an ECR plasma source, comprising the steps of:

• introducing a gas into a plasma generating chamber;
• inducing cyclotron motion of the electrons from the gas by a magnetic field of a first magnetic field source;
• ionizing the gas into a plasma by introducing a microwave beam into the plasma generating chamber which in combination with the magnetic field results in an electron cyclotron resonance condition;
• subjecting the plasma to a uniform reduced magnetic field region within the plasma generating chamber to produce a uniform ion density of the plasma at a reduced magnetization at an extraction system;
• and
• extracting a uniform ion beam from the uniform plasma at a reduced magnetization.