81 results about "Electron drift" patented technology

A Hall field plasma accelerator with closed electron drift includes a composite anode including a housing with inner and outer walls which form an outer anode and an inner anode forming inner and outer distribution zones; the housing is electrically conductive and has an upstream end and an exit port electrically insulated from the housing; the composite anode includes an input distribution system for introducing plasma gas into the distribution zones; poles establish a magnetic field across the exit port and a cathode establishes an electron flow through the magnetic field toward the composite anode and creates an electric field through the exit port; the electrons ionize the plasma gas that is accelerated by the electric field through the exit port.

The invention relates to a multi-region detection system for the partial discharge decomposition components of insulating gas and a method thereof, which belong to the technical field of on-line gas-insulated equipment insulation monitoring. The system comprises a voltage regulator, an isolation transformer, a corona-free test transformer, a partial discharge-free protective resistor, a capacitive divider, an insulating gas discharge decomposition device, an ultrahigh-frequency antenna, an oscillograph, a gas chromatograph-mass spectrometer and the like, and the insulating gas discharge decomposition device comprises a housing, insulating sleeves, connecting rods, electrodes, valves, a vacuum meter, a gas pressure meter, a vacuum pump, an SF6 gas bottle, a pure compressed air bottle and the like. The method utilizes the system to respectively detect the discharge decomposition components of multiple regions in the insulating gas discharge decomposition device. The invention can accurately detect the components and component contents of the decomposed gas of a main gas chamber, a glow discharge region and an electron drift region and provide a standard. The invention can be widely applied to the on-line monitoring of gas-insulated equipment insulation, in particular to the on-line monitoring of GIS (gas-insulated switchgear) insulation.

A design and readout of a xenon detection medium based device, which provides improved spectroscopic performance compared to currently commercially available devices. To achieve energy resolution improvement, a method to accurately measure radial spatial position for interacting events within a HPXe cylindrical detector is described using the plan as shown in FIG. 4. This is accomplished by utilization of light generated both at the gamma interaction site and at the collection point near the anode wire of the cylindrical detector. These light flashes are detected by a VUV photon detector. Light transmission is facilitated by incorporating a vacuum ultraviolet (VUV) light transparent window at least one end of the cylindrical ionization detector. With the known electron drift velocity in HPXe, the time between these two photopulses is sufficient to accurately determine the radial coordinate. Consequently, correction by electronic means for the electrostatic pulse dispersion using the expression graphed in FIG. 2 can be achieved in order to approach the true intrinsic energy resolution limit for HPXe.

The thruster comprises, on a common plate, a plurality of main annular ionization and acceleration channels having axes that are not parallel and that converge in the outlet direction of the channels. A magnetic circuit sets up a magnetic field in the annular channels. The thruster also has a hollow cathode, a device for regulating the ionizable gas feed rate to each annular channel, and a device for controlling the ion discharge acceleration current in the channels. The direction of the thrust vector of the thruster can be controlled without significantly increasing the mass of the thruster.

The closed electron drift plasma accelerator comprises an annular ionization chamber, an acceleration chamber on the same axis as the ionization chamber, an annular anode, a hollow cathode, a first DC voltage source, an annular gas manifold, a magnetic circuit, and magnetic field generators. A coaxial annular coil is placed in the cavity of the ionization chamber, is provided with bias conductive cladding connected, together with the electrically-conductive material of the inside faces of the walls of the ionization chamber, to the positive pole of a second voltage source whose negative pole is connected to the anode, and constitutes an additional magnetic field generator which, together with the other magnetic field generators, forms a magnetic field having a magnetic line of force with an “X” point corresponding to a magnetic field zero situated between the coaxial annular coil and the anode.

The closed electron drift plasma thruster uses a magnetic circuit to create a magnetic field in a main annular channel for ionization and acceleration, said magnetic circuit comprises: an essentially radial first outer pole piece; a conical second outer pole piece; an essentially radial first inner pole piece; a conical second inner pole piece; a plurality of outer magnetic cores surrounded by outer coils to interconnect the first and second outer pole pieces; an axial magnetic core surrounded by a first inner coil and connected to the first inner pole piece; and a second inner coil placed upstream from the outer coils. The thruster also comprises a plurality of radial arms included in the magnetic circuit, and a structural base which is separate from the magnetic circuit and which serves, amongst other things, to cool the coils.

A cylindrical cathode target assembly for use in sputtering target material onto a substrate comprises a generally cylindrical target, means for rotating the target about its axis during a sputtering operation, a magnetic array carried within the target for generation of a plasma-containing field including a plurality of electron drift paths adjacent an outer surface of the target, and a device for supporting the magnetic array independently of rotation of the target. In certain embodiments of the invention, the magnetic array may include a plurality of magnetic elements arranged to form a plurality of electron drift paths spaced along a substantial length of the target to promote generally uniform film deposition and uniform target utilization along its length.

A tandem Hall field plasma accelerator with closed electron drift includes a magnetic circuit having an inner pole and an outer pole and a magnetic field source and a discharge cavity disposed axially in tandem; the discharge cavity including an axially extending accelerator section defining an exit aperture between the inner and outer poles and a plenum section extending radially outwardly and upstream of the accelerator section and including an anode and a propellant injector. Also disclosed is the use of an electromagnetic coil which provides a magnetic field in a magnetic circuit and includes a multiple turn winding wound on an electrically conductive bobbin. The plasma discharge is connected electrically in series with the electromagnetic coil and a power source with a bobbin defining a single turn secondary coil winding on the magnetic circuit which reduces magnetic field fluctuations in the plasma discharge and reduces eddy currents and consequent heating of the magnetic circuit.

PCT No. PCT/FR97/00906 Sec. 371 Date Jan. 21, 1999 Sec. 102(e) Date Jan. 21, 1999 PCT Filed May 23, 1997 PCT Pub. No. WO98/53201 PCT Pub. Date Nov. 26, 1998The ion beam concentration apparatus for a plasma thruster having closed electron drift comprises: a) an essentially frustoconical flared magnetic pole piece (63) open at both ends and designed to be situated downstream from the outlet plane of a plasma thruster having an annular ionization and acceleration channel (1) and peripheral and central pole pieces (3, 4) disposed on either side of the annular channel (1) to produce an essentially radial magnetic field in an outlet plane (14) perpendicularly to the axis of the annular channel (1); and b) an additional peripheral magnetic circuit (60; 80) connecting the downstream end of the flared magnetic pole piece (63) to said peripheral pole piece (3), the flared magnetic pole piece (63) co-operating with the additional peripheral magnetic circuit (60; 80) and with the peripheral and central pole pieces (3, 4) to define the shape of the magnetic field downstream from the annular channel (1) in such a manner as to constrain the ion beam emitted by the annular channel (1) to remain within an essentially conical zone whose predetermined angle at the apex is defined by the angle at the apex of the flared magnetic pole piece (63).

A detector for fast neutrons has been developed which includes 1) selected open structure of solid hydrogen-containing material which converts impinging neutrons into recoil protons; 2) a surrounding gas which interacts with the protons to release electrons; 3) an electric field able to drift the electrons through and away from the open-structure material; and 4) an electron detector which monitors the drifted electrons thereby sensing the original impinging neutrons. This type of detector is advantageous for many applications, including efficient fast neutron detection; large area imaging of fast neutrons for fast neutron radiography; or fast neutron beam profiling.

The present invention discloses an electronic device formed of a group III nitride. In one embodiment, a substrate is fabricated by the ammonothermal method and a drift layer is fabricated by hydride vapor phase epitaxy. After etching a trench, p-type contact pads are made by pulsed laser deposition followed by n-type contact pads by pulsed laser deposition. The bandgap of the p-type contact pad is designed larger than that of the drift layer. Upon forward bias between p-type contact pads (gate) and n-type contact pads (source), holes and electrons are injected into the drift layer from the p-type contact pads and n-type contact pads. Injected electrons drift to the backside of the substrate (drain).

The invention discloses a gallium-nitride-based heterojunction field effect transistor with a combined gate dielectric layer. The gallium-nitride-based heterojunction field effect transistor sequentially and mainly comprises a substrate, a gallium nitride buffering layer, a gallium nitride channel layer, an aluminum gallium nitrogen barrier layer and the combined gate dielectric layer from bottom to top. A source, a drain and a gate are formed on the barrier layer, wherein the source and the drain are in ohmic contact with the barrier layer, and the gate is in schottky contact with the barrier layer. The combined gate dielectric layer is composed of gate dielectric layer bodies different in dielectric constant. In this way, an electric field peak value is formed on the gate dielectric layer interface of the channel layer, a peak value of the electron drifting speed exists at the portion of the electric field peak value, and the drifting speed of electrons in a whole channel is accordingly increased; meanwhile, due to the gate dielectric layer body with the low dielectric constant, the gate capacitance is reduced, and the frequency characteristic of a device is improved.

A focused ion source based on a Hall thruster with closed loop electron drift and a narrow acceleration zone is disclosed. The ion source of the invention has an ion focusing system consisting of two parts. The first part is a ballistic focusing system in which the aperture through which the beam exits the discharge channel is tilted. The second is a magnetic focusing system which focuses the ion beam exiting the discharge channel by canceling a divergent magnetic field present at the aperture through which the beam exits the discharge channel. The ion source of the invention also has an in-line hollow cathode capable of forming a self-sustaining discharge. The invention further reduces substrate contamination, while increasing the processing rate. Further the configuration disclosed allows the ion source to operate at lower operational gas pressures.

The invention belongs to the technical field of deep space detection and discloses a large-area spiral cylindrical double-sided silicon drift detector and a design method thereof. The design method for the large-area spiral cylindrical double-sided silicon drift detector comprises the following steps of determining electric potentials of the front surface and the rear surface of the silicon driftdetector; calculating an optimal drift path from a point S1 to a point S2 for a carrier during drifting in the silicon drift detector by adopting a mathematical variation method; determining a constant drift electric field of the optimal drift path; and calculating width distribution of a spiral negative electrode of the silicon drift detector. According to the method, through analysis on a carrier drift behavior law and heavily doped electrode growth of the SSD, starting from a new structure, a novel process integration design and a light particle theory calculation method, a double-sided electrode having a double-sided correlation effect and capable of keeping an uniform electron drift electric field and providing a smooth drift trajectory is designed, and an innovative design and manufacturing mode of the efficient collection SDD with high energy resolution of soft X-ray particles with the intensity of 0.5-15keV is established.

According to a simultaneous duel model that a de Broglie wave accompanies an electron drift-moving in an electron circuit, wiring is considered as a waveguide of the average de Broglie wave and design was performed by reducing the resistance value at bending portion of the wiring. Furthermore, by providing a micro-structure having a wave suppressing function of average de Broglie wave on the boundary between the metal electrode and the semiconductor electrode, so that electron transmitting probability at the boundary is increased. This improves electric feature of a macro structure portion which may cause a local heating such as a bending corner of wiring contained in the electronic circuit such as an IC and an LSI or a boundary between the metal electrode and the semiconductor electrode.

A radiation detector comprises two electrode arrangements, each including a dielectric substrate and an electrically conducting layer formed on a first surface of respective dielectric substrate, wherein the electrodes are oriented such that the conducting layers are facing each other. A dielectric spacer is provided to hold the electrodes at a distance from each other to thereby define an inter-electrode space, which, during use, is filled with an ionizable gas. The electrodes are held at respective electric potentials to drift electrons released during ionization of the ionizable gas by external radiation towards one of the electrodes for detection. To suppress the occurrence of sparks in the inter-electrode space an electrically conducting layer is formed on a second surface of the dielectric substrate of either one of the electrodes, and, during use, held at a selected electric potential held at a selected electric potential to thereby reduce the risk for occurrence of sparks between the cathode and anode arrangements.

The invention provides a processing method of deep etching a smooth surface based on a SiC substrate slice and relates to the technical field of deep etching of wide bandgap semiconductor materials. The processing method comprises the steps of cleaning the substrate, patterning the SiC substrate slice by virtue of the etched pattern transfer technology, forming a seed layer Ni/Cr/Au by virtue of ultrahigh vacuum magnetron sputtering to realize metal patterning, enhancing the electrical conductivity of the substrate by use of a seed layer, forming a micro-scale thick etching mask layer Ni by virtue of electroplating, gluing the substrate slice with a Si slice, forming a 72 microns deep circular strain film by virtue of RIE deep etching, removing the Si slice and the metal mask, and the like. The processing method has the characteristics of simple preparation method, simple operation process, controllable conditions and the like. Technical and material foundations are laid for the demand on high-temperature, high-power, high-frequency and low-loss devices having such characteristics of wide bandgap, high breakdown electric field, high electrical conductivity and high saturated electron drift velocity in the electronic industrial product market.

The invention belongs to the technical field of deep space detection, and discloses a large-area concentric-circles-shaped cylindrical double-surface silicon drift detector and a design method thereof. The design method of the large-area concentric-circles-shaped cylindrical double-surface silicon drift detector comprises the following steps: determining electric potentials of the front surface and the rear surface of the silicon drift detector; calculating an optimal drift path from a point S1 to a point S2 when a current carrier drifts in the silicon drift detector by using a mathematic variational method; and determining a constant drift electric field of the optimal drift path. An SDD current carrier drift behavior law and heavy doping electrode growth are analyzed, a double-surface electrode which has double-surface correlation, not only maintains a uniform electron drift electric field, but also provides a smooth drift track is designed from a new structure, novel process integrated design and a theoretical calculating method for the corpuscular property of light, and a creative design manufacturing mode which is high in energy resolution ration on soft X-ray particles with the strength being 0.5-15 keV and effectively collects SDD is established.

In a closed electron drift thruster, a magnetic circuit for creating a magnetic field in a main annular channel comprises at least one axial magnetic core surrounded by a first coil and an inner upstream pole piece forming a body of revolution, together with a plurality of outer magnetic cores surrounded by outer coils. The magnetic circuit further comprises an essentially radial outer first pole piece defining a concave inner peripheral surface and an essentially radial second pole piece defining a convex outer peripheral surface. The concave inner peripheral surface and the convex outer peripheral surface present respective adjusted profiles that are distinct from circular cylindrical surfaces so as to form between them a gap of varying width presenting zones of maximum value in register with the outer coils and zones of minimum value in between the outer coils so as to create a uniform radial magnetic field.

There is provided a semiconductor device or the like which includes a channel and a gate electrode in an opening and in which electric field concentration near a bottom portion of the opening can be reduced. The semiconductor device includes n⁻-type GaN drift layer 4/p-type GaN barrier layer 6/n⁺-type GaN contact layer. An opening 28 extends from the top layer and reaches the n-type GaN-based drift layer. The semiconductor device includes a regrown layer 27 located in the opening, the regrown layer 27 including an electron supply layer 26 and an electron drift layer 22, a source electrode S, a drain electrode D, a gate electrode G located on the regrown layer, and a semiconductor impurity adjustment region 31 disposed in the bottom portion of the opening. The impurity adjustment region 31 is a region that promotes a potential drop from the drain electrode side to the gate electrode side in a potential distribution in an off-state.

The invention discloses a lattice-structured electron drift tube. The lattice cathode of the electron drift tube converts X-rays radiated by a target into electron pulse strings distributed in a spatial array, the electron pulse strings drift at a high speed under the action of a gradual change electric field with non-interfering spatial arrays, and the spatial scale of the electron pulse stringsin the drift is fully guaranteed. The electron pulse strings pass through a rear-end grid mesh distributed in an equal-ratio space array, is multiplied by a microchannel plate and then bombards a fluorescent screen to emit light, and the electric signal is converted into an optical signal again, and the electron pulse strings are in a uniform magnetic field generated by a magnetic coil with a shielding shell in the whole process. The electron drift tube can obviously improve the spatial resolution characteristic in an electron uniform-speed drift region, furthest reduce the spatial transversecrosstalk of the electron pulse strings by utilizing the magnetic field constraint, achieve spatial fidelity and a large dynamic range, contribute to promoting the development of an ultrahigh time-resolution two-dimensional imaging diagnosis technology, and have important significance for improving the precision level of laser inertial constraint fusion diagnosis.