Research Triangle Institute

Sharp Kabushiki Kaisha Corporation

Minnesota Mining and Manufacturing Company

Berkeley Scholars, Inc.

Reserach Triangle Institute, Inc.

Robert C Hendry

Robert J Markunas

Ronald A Rudder

Moses Mekala David

Anthony E Robson

George Carlton Hudson

Gaius G Fountain

James V Burt

Tatsuo Morita

Rama Venkatasubramanian

Bing A Shen

Masataka Itoh

Raymond E Thomas

John Posthill

Cynthia Watkins

Gill Fountian

George C Hudson

Michael J Mantini

A power conversion unit and method for converting DC power. The power conversion unit includes a self-oscillating device configured to convert a DC voltage into a self-oscillating alternating current AC signal, a transformer connected to the self-oscillating device and configured to transform the self-oscillating AC signal into a transformed AC signal, and an AC-to-DC converter configured to convert the transformed AC signal into a DC signal. The method generates a self-oscillating current, transforms the self-oscillating current into a transformed AC signal, and converts the transformed AC signal into a DC signal.

DC-DC converter for low voltage power source

A plasma processing system and method wherein a power source produces a magnetic field and an electric field, and a window disposed between the power source and an interior of a plasma chamber couples the magnetic field into the plasma chamber thereby to couple power inductively into the chamber and based thereon produce a plasma in the plasma chamber. The window can be shaped and dimensioned to control an amount of power capacitively coupled to the plasma chamber by means of the electric field so that the amount of capacitively coupled power is selected in a range from zero to a predetermined amount. Also, a tuned antenna strap having r.f. power applied thereto to produce a standing wave therein can be arranged adjacent the window to couple magnetic field from a current maximum formed in the strap to the interior of the chamber. A desired amount of magnetic field and/or electric field coupling can be produced by arrangement of the chamber window adjacent that portion of the antenna strap exhibiting the desired current/voltage relationship. The system may be formed in a line source configuration, or in a cylindrical source configuration. The window may have slots and/or apertures, the size and shape of which may be variable.

Plasma processing system and method

A method and apparatus for plasma waste disposal of hazardous waste material, where the hazardous material is volatilized under vacuum inside a containment chamber to produce a pre-processed gas as input to a plasma furnace including a plasma-forming region in which a plasma-forming magnetic field is produced. The pre-processed gas is passed at low pressure and without circumvention through the plasma-forming region and is directly energized to an inductively coupled plasma state such that hazardous waste reactants included in the pre-processed gas are completely dissociated in transit through the plasma-forming region. Preferably, the plasma-forming region is shaped as a vacuum annulus and is dimensioned such that there is no bypass by which hazardous waste reactants in the pre-processed gas can circumvent the plasma-forming region. The plasma furnace is powered by a high frequency power supply outputting power at a fundamental frequency. The power supply contains parasitic power dissipation mechanisms to prevent non-fundamental, parasitic frequencies from destabilizing the fundamental frequency output power. These power loss mechanisms use either distributed resistance or frequency-selective power-loss devices to prevent parasitic oscillations from instantaneously turning on the high frequency power oscillator at non-fundamental frequencies.

Plasma furnace disposal of hazardous wastes

A method and apparatus for treating a work surface, wherein there is provided a chamber having a longitudinal axis and longitudinally extending electrically conductive sidewalls, at least one sidewall having at least one longitudinally extending gap that interrupts a current path through the sidewalls transverse to the longitudinal axis, and wherein the chamber is sealed to allow pressure inside the chamber to be controlled. Also provided is an axially-extending array of current-carrying conductors which at least partially encircle the chamber, are transverse to the longitudinal axis, and establish a magnetic field parallel to the longitudinal axis of the chamber, and a power supply connected to the conductor array and adapted to provide high-frequency current in the conductors to magnetically induce ionization of the gaseous material in the chamber and form a plasma sheath that surrounds and extends along the longitudinal axis and conforms to the sidewalls of the chamber, and wherein the work surface is exposed to the plasma sheath and extends in the direction of the longitudinal axis.

Durable plasma treatment apparatus and method

A line plasma source (20) comprises a plasma chamber (30) configured so that plasma (32) is situated remotely and on-edge with respect to a polycrystalline silicon surface (20S) to be treated, thereby preventing damage to the surface, facilitating treatment of large substrates, and permitting low temperature operation. Active species exit the plasma chamber through a long narrow ('line') outlet aperture (36) in the plasma chamber to a reaction zone (W) whereat the active species react with a reaction gas on the polycrystalline silicon surface (e.g., to form a deposited thin film). The polycrystalline silicon surface is heated to a low temperature below 6000.degree. C. Hydrogen is removed from the reactive surface in the low temperature line plasma source by a chemical displacement reaction facilitated by choice of dominant active species (singlet delta state of molecular oxygen). Reaction by-products including hydrogen are removed by an exhaust system (100) comprising long narrow exhaust inlet apertures (114L,114R) extending adjacent and parallel to the outlet aperture of the plasma chamber. An ionizing electric field is coupled to the plasma across a smallest dimension of the plasma, resulting in uniform production of active species and accordingly uniform quality of the thin film. The polycrystalline silicon surface to be treated is translated with respect to the plasma line source in a direction perpendicular to the outlet aperture of the plasma line source for integrating thin film quality in the direction of translation (22).

Line plasma vapor phase deposition apparatus and method

A method and apparatus for generating plasmas adapted for chemical vapor deposition, etching and other operations, and in particular to the deposition of large-area diamond films, wherein a chamber defined by sidewalls surrounding a longitudinal axis is encircled by an axially-extending array of current-carrying conductors that are substantially transverse to the longitudinal axis of the chamber, and a gaseous material is provided in the chamber. A high-frequency current is produced in the conductors to magnetically induce ionization of the gaseous material in the chamber and form a plasma sheath that surrounds and extends along the longitudinal axis and conforms to the sidewalls of the chamber. A work surface extending in the direction of the longitudinal axis of the chamber is positioned adjacent a sidewall, exposed to the plasma sheath and treated by the plasma. Preferably, the ratio of the width to the height of the chamber is 10:1 or larger so that the chamber includes a large area planar surface adjacent the plasma sheath and adjacent to which a large area substrate or a plurality of substrates is arranged, whereby large area treatment, such as diamond deposition, can be performed.

Plasma treatment method for treatment of a large-area work surface

A chemical vapor deposition (CVD) process and apparatus for the growth of diamond films using vapor mixtures of selected compounds having desired moieties, specifically precursors that provide carbon and etchant species that remove graphite. The process involves two steps. In the first step, feedstock gas enters a conversion zone. In the second step, by-products from the conversion zone proceed to an atomization zone where diamond is produced. In a preferred embodiment a feedstock gas phase mixture including at least 20% water which provides the etchant species is reacted with an alcohol which provides the requisite carbon precursor at low temperature (55.degree.-1100.degree. C.) and low pressure (0.1 to 100 Torr), preferably in the presence of an organic acid (acetic acid) which contributes etchant species reactant. In the reaction process, the feedstock gas mixture is converted to H.sub.2, CO, C.sub.2 H.sub.2, no O.sub.2, with some residual water. Oxygen formerly on the water is transferred to CO. Hence, an etchant species (H.sub.2 O, OH, O) is replaced in the reactor by CO, a growth species and prevents undesirous consumption of diamond (the net-product). In a preferred embodiment, the apparatus assures conversion by preventing gas circumvention of the conversion zone prior to dissociation in the hydrogen atomization zone to produce the necessary atomic hydrogen for diamond growth.

Process and apparatus for chemical vapor deposition of diamond films

A chemical vapor deposition (CVD) technique (process and apparatus) for the growth of diamond films using vapor mixtures of selected compounds having desired moieties, specifically precursors that provide carbon and etchant species that remove graphite disclosed. The selected compounds are reacted in a plasma created by a confined rf discharge to produce diamond films on a diamond or a non-diamond substrate. In a preferred embodiment a gas phase mixture including at least 20% water which provides the etchant species is reacted with an alcohol which provides the requisite carbon precursor at low temperature (300.degree.-650.degree. C.) and low pressure (0.1 to 10 Torr), preferably in the presence of an organic acid (acetic acid) which contributes etchant species reactant. In the preferred embodiment the volumetric mixtures have typically been 40-80% water and 60-20% alcohol. The gaseous mixture of H.sub.2 O and alcohol is dissociated to produce H, OH, and carbon radicals. Both OH and atomic H are capable of etching graphite from the depositing carbon layer. The selected compounds are reacted in a CVD apparatus in which a confined rf discharge is used to create an electric discharge or plasma. The plasma is confined between an inductive rf coil via transformer isolation from the chamber ground.

Chemical vapor deposition of diamond films using water-based plasma

A remote plasma enhanced CVD apparatus and method for growing semiconductor layers on a substrate, wherein a intermediate feed gas, which does not itself contain constituent elements to be deposited, is first activated in an activation region to produce plural reactive species of the feed gas. These reactive species are then spatially filtered to remove selected of the reactive species, leaving only other, typically metastable, species which are then mixed with a carrier gas including constituent elements to be deposited on the substrate. During this mixing, the selected spatially filtered reactive species of the feed gas chemically interacts, i.e., partially dissociates and activates, in the gas phase, the carrier gas, with the process variables being selected so that there is no back-diffusion of gases or reactive species into the feed gas activation region. The dissociated and activated carrier gas along with the surviving reactive species of the feed gas then flows to the substrate. At the substrate, the surviving reactive species of the feed gas further dissociate the carrier gas and order the activated carrier gas species on the substrate whereby the desired epitaxial semiconductor layer is grown on the substrate.

Remote plasma enhanced CVD method and apparatus for growing an epitaxial

A remote plasma enhanced CVD apparatus and method for growing semiconductor layers on a substrate, wherein an intermediate feed gas, which does not itself contain constituent elements to be deposited, is first activated in an activation region to produce plural reactive species of the feed gas. These reactive species are then spatially filtered to remove selected of the reactive species, leaving only other, typically metastable, species which are then mixed with a carrier gas including constituent elements to be deposited on the substrate. During this mixing, the selected spatially filtered reactive species of the feed gas chemically interacts, i.e., partially dissociates and activates, in the gas phase, the carrier gas, with the process variables being selected so that there is no back-diffusion of gases or reactive species into the feed gas activation region. The dissociated and activated carrier gas along with the surviving reactive species of the feed gas then flows to the substrate. At the substrate, the surviving reactive species of the feed gas further dissociate the carrier gas and order the activated carrier gas species on the substrate whereby the desired epitaxial semiconductor layer is grown on the substrate.

Growing community of inventors

Hillsborough, NC, United States of America

Robert C Hendry