Patent•
method of powering corona discharge in ozone generators
14 Jun 1990-
TL;DR: In this article, the first pulse of each pair of unipolar pulses is configured to make the dielectric electrode electronically negative with respect to the metal electrode to decrease acoustic and mechanical resonances and fatigue to system components.
Abstract: A method of supplying electrical power to and controlling corona discharge cells used for the generation of ozone employs a single-cycle discontinuous waveform which is characterized by a fixed pulse width and a variable repetition rate. Discrete bipolar pulses are composed of a pair of unipolar pulses of opposite polarity. The bipolar pulse repetition rate is varied to control the average corona power, providing an infinite turndown of ozone output. When powering discharge cells which are asymmetric in their response to pulse polarity, such as those containing a dielectric coated with a conducting surface as a first electrode and a metal as a second electrode, the present invention configures the first pulse of each pair to make the dielectric electrode electronically negative with respect to the metal electrode. This polarity sequence produces a more stable corona and far less electrical noise. Furthermore, to decrease acoustic and mechanical resonances and fatigue to system components and to the human ear, this invention broadens the frequency distribution of the pulse repetition rate by repetitively sweeping or randomly jittering the intervals between bipolar pulses.
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01 Aug 2008
TL;DR: In this article, the oxide semiconductor film has at least a crystallized region in a channel region, which is defined as a region of interest (ROI) for a semiconductor device.
Abstract: An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.
1,501 citations
Patent•
16 Feb 2005TL;DR: In this article, a bypass pipe is connected between the mechanical booster pump and the rest vacuum pumps located at a downstream side of the booster pump to prevent the exhaust gas from diffusing back to the inside of a process chamber.
Abstract: Process gas discharged from a bypass pipe to a gas exhaust system can be prevented from diffusing back to the inside of a process chamber without having to install a dedicated vacuum pump at the downstream side of the bypass pipe. The substrate processing apparatus includes a process chamber accommodating a substrate, a gas supply system supplying process gas from a process gas source to the process chamber for processing the substrate, a gas exhaust system configured to exhaust the process chamber, two or more vacuum pumps installed in series at the gas exhaust system, and a bypass pipe connected between the gas supply system and the gas exhaust system. The most upstream one of the vacuum pumps is a mechanical booster pump, and the bypass pipe is connected between the mechanical booster pump and the rest vacuum pumps located at a downstream side of the mechanical booster pump.
644 citations
Patent•
23 Jun 1998TL;DR: In this article, a transformer with a magnetic core surrounding a portion of a plasma chamber and a primary winding was described. But the transformer was not designed for dissociating gases.
Abstract: An apparatus for dissociating gases includes a plasma chamber that may be formed from a metallic material and a transformer having a magnetic core surrounding a portion of the plasma chamber and having a primary winding. The apparatus also includes one or more switching semiconductor devices that are directly coupled to a voltage supply and that have an output coupled to the primary winding of the transformer. The one or more switching semiconductor devices drive current in the primary winding that induces a potential inside the chamber that forms a plasma which completes a secondary circuit of the transformer.
361 citations
Patent•
28 Oct 2011TL;DR: In this paper, a gas channel plate for a semiconductor process module is described, which includes a heat exchange surface including a plurality of heat exchange structures separated from one another by intervening gaps.
Abstract: Embodiments related to managing the process feed conditions for a semiconductor process module are provided. In one example, a gas channel plate for a semiconductor process module is provided. The example gas channel plate includes a heat exchange surface including a plurality of heat exchange structures separated from one another by intervening gaps. The example gas channel plate also includes a heat exchange fluid director plate support surface for supporting a heat exchange fluid director plate above the plurality of heat exchange structures so that at least a portion of the plurality of heat exchange structures are spaced from the heat exchange fluid director plate.
281 citations
Patent•
13 Nov 2009TL;DR: In this paper, a method of forming an insulation film by alternating multiple times, respectively, a process of adsorbing a precursor onto a substrate and treating the adsorbed surface using reactant gas and a plasma, wherein a plasma is applied in the process of supplying the precursor.
Abstract: A method of forming an insulation film by alternating multiple times, respectively, a process of adsorbing a precursor onto a substrate and a process of treating the adsorbed surface using reactant gas and a plasma, wherein a plasma is applied in the process of supplying the precursor.
215 citations
References
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Patent•
03 Apr 1986
TL;DR: In this paper, a versatile pulsed voltage resonant inverter power supply for an ozonator which results in the efficient operation of the ozonators is presented. But the voltage at which the thyristors are triggered is selected to be lower than the circuit resonant frequency in order that the load voltage supplied by the inverter is substantially pulsed, and a pulse burst modulation mode is also disclosed.
Abstract: A versatile pulsed voltage resonant inverter power supply for an ozonator which results in the efficient operation thereof A resonant inverter ozonator power supply comprises a DC power source and a DC/AC thyristor inverter coupled at its outputs to the primary winding of a high voltage transformer The ozonator load is connected across the secondary winding of transformer and provides a discharge path during each high frequency cycle First and second embodiments of control circuits are disclosed for generating gating control signals for the thyristors The switching frequency at which the thyristors are triggered is selected to be lower than the circuit resonant frequency in order that the load voltage supplied by the inverter is substantially pulsed, and a pulse burst modulation mode is also disclosed
45 citations
Patent•
04 Apr 1979TL;DR: In this article, it was found that for many corona discharge reactions, such as the conversion of oxygen to ozone, the present method increases the electrical efficiency of the reaction, which increases the power consumption of the corona.
Abstract: Corona induced chemical reactions are conducted in a corona discharge zone in which narrow high voltage pulses are applied along with a relatively low voltage bias potential. It is found that for many corona discharge reactions, such as the conversion of oxygen to ozone, the present method increases the electrical efficiency of the reaction.
30 citations
Patent•
19 Dec 1974TL;DR: In this article, a solid state power supply circuit for a corona generator type device where two alternately fired load commutated SCR (Silicon Controlled Rectifier) means conduct in opposite directions through the primary winding of a power transformer is described.
Abstract: A solid state power supply circuit for a corona generator type device wherein two alternately fired load commutated SCR (Silicon Controlled Rectifier) means conduct in opposite directions through the primary winding of a power transformer. Each SCR means is series connected to a separate DC power source and isolated from the other SCR means by means of diodes. A corona generator is connected to the secondary of the power transformer and receives symmetrical, bipolar power pulses from the power supply circuit.
17 citations
Patent•
04 Mar 1981
TL;DR: In this paper, a servo system chain comprising devices for controlling the duration of the initiating signals by means of a set signal, having regard to the total ozonization produced by the n ozonizers.
Abstract: The ozonization installation comprises a group of n ozonizers supplied with energy by a common source in a successive alternating voltage wave train mode, the application of the wave trains being controlled by a control device. The latter produces initiating signals which selectively enable the passage of the electric energy in the form of wave trains coming from the common source to the ozonizer. The installation comprises a servo system chain comprising devices for controlling the duration of the initiating signals by means of a set signal, having regard to the total ozonization produced by the n ozonizers. This duration corresponds to that of each successive wave train. Synchronization devices are provided for connecting the common energy source to solely one ozonizer at a time.
12 citations