Applied Microwave Plasma Concepts, Inc.

Other

Tokyo Electron Limited

Asm Japan K.k.

Asm International N.v.

Raphael A Dandl

Wayne L Johnson

Bill H Quon

Gareth E Guest

Andrej Mitrovic

Samuel S Antley

A plasma transport system uses a slow-wave power signal in external radio-frequency (RF) inductors to force plasmas to flow through ducts, such as from a plasma generator to a point of use. A magneto-hydrodynamic force is deliberately created by the RF inductors to displace plasma electrons down along the inside of the ductwork. A charge separation results that both drags the ions along and slows down the electrons with the ion drag. The consequence is that both electrons and ions are motivated down the ductwork and the overall plasma charge stays neutral. A directed stream of energetic ions and neutral gas atoms can be realized. The RF electric fields induced in the plasma tend to counteract any electron cooling and help maintains the plasma electron temperature enough to reduce later reionization power demands.

Slow-wave induction plasma transport

A stand-alone plasma vacuum pump for pumping gas from a low-pressure inlet to a high-pressure outlet, composed of: a housing enclosing one or more pumping regions located between the inlet and the outlet; a plurality of permanent magnet assemblies providing magnetic fields that extend in the pumping region between the inlet and the outlet, the magnetic field forming magnetic flux channels for guiding and confining plasmas; elements disposed for coupling microwave power into the flux channels to heat electrons, ionize gas, and accelerate plasma ions in a direction from the inlet to the outlet; elements disposed for creating an electric in the magnetic flux channels to accelerate ions in the flux channels toward the outlet by momentum transfer; and a differential conductance baffle proximate to the outlet for promoting flow of plasma ions and neutral atoms to the outlet.

Stand alone plasma vacuum pump

A plasma vacuum pump including an array of permanent magnets, one or more plasma conduits or ducts, components for accelerating plasma ions through these conduits, and supporting structures that together comprise at least one applied plasma duct system (APDS) cell. The APDS cell permits large volumes of particles and plasma to flow rapidly in a preferred direction while constricting the flow of neutral particles in the reverse direction. A plasma pump utilizing APDS technology is intended to permit a large throughput of ionized gas at the intermediate pressures of interest in the plasma-enhanced processing industry, compressing this gas to a pressure at which blower-type pumps can be used efficiently to exhaust the spent processing gas at atmospheric pressure.

Applied plasma duct system

A plasma pump and method for pumping ions from a first to second region, the pump including a partition member having a through opening defining a plurality of conduits ( ); a group of magnets ( ) to provide magnetic forces that extend to the conduits; and a plurality of electric potential sources ( ) for creating electrostatic fields which accelerate ions from the conduits to the second region.

Plasma vacuum pump

A plasma pumping cell and method for pumping ions from a first region containing a plasma to a second region when the plasma pumping cell is interposed between the first and second regions, the plasma pumping cell including: a partition member ( ) positioned between the first and second regions, the partition member ( ) having a through opening defining a conduit ( ); a plurality of magnets ( ) positioned relative to the conduit in a manner to provide lines of magnetic force that extend through the conduit; a source of free electrons in communication with the conduit; and an electric potential source ( ) disposed relative to the conduit to create an electrostatic field which accelerates ions from the conduit ( ) to the second region.

Plasma vacuum pumping cell

A method and apparatus employing a microwave applicator for use with an ECR plasma source for applications including etching and chemical vapor deposition is provided. A magnetic field is generated by magnets circumferentially arranged about a chamber that is symmetrical about its longitudinal axis. The microwave applicator, which comprises at least one pair of coaxial resonant multiport microwave antenna arrays, injects and distributes microwave power about a plasma forming portion of the chamber. The antenna arrays include a plurality of radiating stubs for radiating microwave power. The stubs are positioned along the arrays at predetermined intervals and selected orientations relative to a coaxial transmission line, for efficiently distributing microwave power uniformly about the plasma forming portion. The position and orientation of the radiating stubs cause microwave power to be launched into the plasma in the form of propagating electromagnetic waves with a polarization suitable for electron cyclotron heating. The applicator is coupled to a microwave power source that preferably supplies microwave power at a frequency of 2.45 GHz. A magnetic-field free region produces uniformity of plasma distribution in a plasma stream that approaches an outlet in the chamber. The plasma stream flows through the plasma forming region toward the specimen with characteristics of high density, uniformity over transverse dimensions larger than the specimen, and low plasma temperature, while operating at gas pressures which can be varied over a wide range.

Coaxial resonant multi-port microwave applicator for an ECR plasma source

A method and apparatus are disclosed employing a microwave applicator for use with an electron cyclotron resonance (ECR) plasma source for applications including, but not limited to, etching and chemical vapor deposition. A magnetic field is generated by magnets circumferentially arranged about a chamber that is symmetrical about its longitudinal axis. The microwave applicator, which comprises one or more pairs of slotted antenna arrays, injects and distributes microwave power about the entire periphery of a plasma forming portion of the chamber. The antenna arrays include a plurality of radiating stubs for radiating microwave power. The stubs are positioned along the arrays at predetermined intervals for efficiently distributing microwave power uniformly about the periphery of the plasma forming portion. The position and orientation of the radiating stubs cause microwave power to be launched into the plasma in the form of propagating waves with a polarization suitable of electron cyclotron heating. The applicator is coupled to a microwave power source that preferably supplies microwave power at a frequency of 2.45 GHz. A magnetic-field free region produces uniformity of plasma distribution in a plasma stream that approaches an outlet in the chamber. The plasma stream flows through the plasma forming region toward the specimen with characteristics of high density, uniformity over transverse dimensions larger than the specimen, and low plasma temperature, while operating at gas pressures which can be varied over a wide range.

Coaxial microwave applicator for an electron cyclotron resonance plasma

A method and apparatus are disclosed employing electron cyclotron resonant (ECR) heating to produce plasma for applications including but not limited to chemical vapor deposition and etching. A magnetic field is formed by magnets circumferentially arranged about a cylindrical and symmetrical chamber with microwave power injected perpendicularly to a longitudinal axis of the chamber for preventing line-of-sight communication of resulting energetic electrons with a specimen being treated. The microwave power is distributed uniformly around the circumference of the chamber by applicators formed by one or more pairs of annular sectors, each of which comprises a slotted wave guide antenna, and coupled to an external source of microwave power by a hybrid coupler. A magnetic field free region produces uniformity of plasma distribution in a plasma stream approaching the outlet. The above characteristics are maintained for the plasma stream over substantial transverse dimensions larger than the specimen. A rectilinear applicator array is also disclosed for selected applications.

Electron cyclotron resonance plasma source and method of operation

A method is disclosed employing electron cyclotron resonant (ECR) heating to produce plasma for applications including but not limited to chemical vapor deposition and etching. A magnetic field is formed by magnets circumferentially arranged about a cylindrical and symmetrical chamber with microwave power injected perpendicularly to a longitudinal axis of the chamber for preventing line-of-sight communication of resulting energetic electrons through an outlet at one axial end of the chamber. The circumferential magnets in the symmetrical chamber cause precessing of the electrons resulting in greatly increased plasma density and ion flux or current density even at low gas pressures which are preferably maintained for establishing unidirectionality or anisotropic plasma characteristics. A magnetic field free region is formed between the plasma forming region containing the microwave power source and the circumferential magnets in order to also produce uniformity of plasma distribution in a plasma stream approaching the outlet. Thus, with specimens arranged in communication with the outlet, the above characteristics are maintained for the plasma stream over substantial transverse dimensions larger than the specimen.

Method of operation of electron cyclotron resonance plasma source

A method and apparatus are disclosed employing electron cyclotron resonant (ECR) heating to produce plasma for applications including but not limited to chemical vapor deposition and etching. A magnetic field is formed by magnets circumferentially arranged about a cylindrical and symmetrical chamber with microwave power injected perpendicularly to a longitudinal axis of the chamber for preventing line-of-sight communication of resulting energetic electrons through an outlet at one axial end of the chamber. The circumferential magnets in the symmetrical chamber cause precessing of the electrons resulting in greatly increased plasma density and ion flux or current density even at low gas pressures which are preferably maintained for establishing unidirectionality or anisotropic plasma characteristics. A magnetic field free region is formed between the plasma forming region containing the microwave power source and the circumferential magnets in order to also produce uniformity of plasma distribution in a plasma stream approaching the outlet. Thus, with specimens aranged in communication with the outlet, the above characteristics are maintained for the plasma stream over substantial transverse dimensions larger than the specimen.

Electron cyclotron resonance plasma source

A method and apparatus are disclosed for producing microwave radiation wherein a generally stable, high-beta, relativistic electron plasma is formed in a static magnetic field of a suitable enclosure either by an external microwave source or in situ within the plasma by means of at least one pair of steady-state interacting energetic electron beams, a convectively unstable wave then being created in the confined plasma either internally in an oscillator mode or externally in an amplifier mode by means of an external launcher for producing a pulse of relatively intense microwave radiation at a frequency near a local electron gyrofrequency. The above steps or functions are preferably sequentially repeated with sequential pulses of microwave radiation being withdrawn from the enclosure, focused by quasi-optical means and directed toward a target including electronic circuitry, so that the beam of sequential pulses is coupled into the electronic circuitry for developing substantial amounts of energy therein.

Method and apparatus for producing intense microwave pulses

A method and apparatus are disclosed for producing microwave radiation wherein a generally stable, high-beta, relativistic electron plasma is formed and magnetically confined in a magnetic mirror region of a suitable enclosure, a convectively unstable wave then being created in the confined plasma for producing a pulse of relatively intense microwave radiation at a frequency near a local electron gyrofrequency of the plasma, the plasma preferably being formed by simultaneous multiple-frequency electron cyclotron heating and upper off-resonant heating using microwave power at frequencies above the electron gyrofrequency of the plasma. The above steps or functions are preferably sequentially repeated with sequential pulses of microwave radiation being withdrawn from the enclosure, focused by quasi-optical means and directed toward a target including electronic circuitry, the method and apparatus of the invention being preferably adapted for causing the beam of sequential pulses to be coupled into the electronic circuitry for developing substantial amounts of energy therein.

Method and apparatus for producing microwave radiation

A method and apparatus is disclosed for producing a gas pumping plasma within an evacuated enclosure having a collimating system consisting of baffle structures and a magnetic field having a central uniform region connected to a source of neutral gas, a magnetic mirror intermediate region and a terminating divergent region. According to the method and apparatus of the present invention, the enclosure is evacuated to a selected pressure, high frequency microwave energy of a selected power and frequency is fed into the magnetic mirror intermediate region, the magnetic field is established at a strength such that an electron cyclotron frequency is made equal to the frequency of the microwave energy within the intermediate region, electrons within the magnetic mirror intermediate region being heated by the microwave energy, the heated electrons ionizing the neutral gas in the intermediate and central regions for creating and maintaining a pumping plasma. Baffle structures are provided between the central and intermediate regions and between the intermediate and terminal regions for permitting unobstructed flow of plasma along the magnetic field lines to the terminal region while restricting inward flow of neutral gas resulting from recombination in the terminal region. The plasma is preferably composed of ionized neutral gas from the central and intermediate regions and an adequate neutral gas concentration is maintained in the intermediate region by controlled supply of make-up gas.

Growing community of inventors

San Marcos, CA, United States of America

Raphael A Dandl