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A plasma arc discharge method for deposition of metallic and semiconductor layers on a substrate for the purpose of producing semiconductor grade materials such as silicon at a reduced cost. Magnetic fields are used so that silicon ions and electrons can be directed toward a target area where they a

A plasma arc discharge method for deposition of metallic and semiconductor layers on a substrate for the purpose of producing semiconductor grade materials such as silicon at a reduced cost. Magnetic fields are used so that silicon ions and electrons can be directed toward a target area where they are deposited. The ions and electrons are preferably injected as a compound in gaseous of liquid form but may also be injected in liquid elemental form or vaporized from a thermionic cathode. The magnetic fields include an accelerating magnetic field and a focusing magnetic field. The accelerating magnetic field is adjusted to support a desired high ion flux rate and the focusing magnet can control the plasma beam direction and divergence. The silicon provided in a compound form or in the form of metallurigical silicon is purified during the deposition process by a carrier substance which may be a part of the compound or separately injected. Chemical purification is accomplished by separation of the silicon due to ionization potential differences between silicon and other elements. The magnetic acceleration technique allows the use of pressures under 10-1 torr thereby facilitating plasma formation and allowing the materials to be deposited with a desired high purity.

대표청구항 ▼

An apparatus for refining semiconductor materials by using a plasma spray magnetically accelerated in a vacuum comprising: (a) a vacuum chamber and associated vacuum pumping apparatus; (b) a magnetoplasmadynamic Hall effect plasma generator, the plasma generator further comprising: a cathode an anod

An apparatus for refining semiconductor materials by using a plasma spray magnetically accelerated in a vacuum comprising: (a) a vacuum chamber and associated vacuum pumping apparatus; (b) a magnetoplasmadynamic Hall effect plasma generator, the plasma generator further comprising: a cathode an anode an accelerating magnet located adjacent that portion of the cathode closest to the anode; a focusing magnet at least part of which is located beyond the anode with respect to the cathode; (c) a plasma generator support structure, the support structure supporting the plasma generator within the vacuum chamber; (d) a means to supply the plasma generator with electric power, the electric power being primarily direct current and the power enabling the plasma generator to create a plasma; (e) a target surface, the target surface being located beyond the focusing magnet with respect to the cathode and anode; (f) a means for injecting materials into the plasma in order to create a plasma stream; (g) an access door enabling access to the inside of the vacuum chamber from the outside, the access door having sealing means, whereby said injected materials are preferentially ionized by the plasma generator, thereby causing impurities in the materials to separate while they are in the plasma stream.