Abstract:
An electron beam device wherein a low temperature gaseous plasma is generated in a chamber divided by two parallel wire grids. A semiconductor wafer serves as a cathode drawing ions from the plasma to impinge on the wafer, generating secondary electrons that are accelerated toward an anode on the opposite side of the grids where a target resides. In order to have a beam with uniform cross-sectional flux characteristics, the semiconductor wafer is doped with a graded dopant concentration that promotes a uniform beam.
Abstract:
An electron beam device wherein a low temperature gaseous plasma is generated in a chamber divided by two parallel wire grids. A semiconductor wafer serves as a cathode drawing ions from the plasma to impinge on the wafer, generating secondary electrons that are accelerated toward an anode on the opposite side of the grids where a target resides. In order to have a beam with uniform cross-sectional flux characteristics, the semiconductor wafer is doped with a graded dopant concentration that promotes a uniform beam.
Abstract:
A method of generating light comprising the step of applying an electric field to an excimer-forming gas such as a gas mixture containing noble gases and hydrogen or halogen, and providing free electrons in the gas. The electric field is configured to accelerate electrons to at least the energy required to form excimers, but in at least one region of the electric field, the field does not substantially ionize the gas, so that the field does not induce arcing through the gas. For example, electrons can be injected from one or more field emission electrodes (18) such as one or more a metal needle tip conductors, whereas the electric field can be a field between the field emission electrodes and a counterelectrode (13).
Abstract:
A discharge device for operation in a gas at a prescribed pressure includes a cathode having a plurality of micro hollows therein, and an anode spaced from the cathode. Each of the micro hollows has dimensions selected to produce a micro hollow discharge at the prescribed pressure. Preferably, each of the micro hollows has a cross-sectional dimension that is on the order of the mean free path of electrons in the gas. Electrical energy is coupled to the cathode and the anode at a voltage and current for producing micro hollow discharges in each of the micro hollows in the cathode. The discharge device may include a discharge chamber for maintaining the prescribed pressure. A dielectric layer may be disposed on the cathode when the spacing between the cathode and the anode is greater than about the mean free path of electrons in the gas. Applications of the discharge device include fluorescent lamps, excimer lamps, flat fluorescent light sources, miniature gas lasers, electron sources and ion sources.
Abstract:
A plasma compensation cathode includes a casing (1) accommodating coaxially with its outlet hole (2) a hollow holder (3) and a thermal emitter (4) with a central passage (5), a layer (10) of material chemically inert at high temperatures to the materials of the holder and emitter being interposed therebetween. The central passage (5) is blind at the side of admission of gas, and is communicated with the interior of the holder (3) by way of a through passage (8) made in the wall of the thermal emitter (4) so that its axis intersects the axis of passage (5), and longitudinal grooves (9) made in the side surface of the thermal emitter (4) at the location of the inlet holes of the through passage (8). The holder (3) is embraced by heater (6) having a support ring (7) positioned in its midportion and secured in an insulation sleeve (18) separating the heater (6) from the coaxial heat screens (11) interconnected successively to define a sealed cavity (14) wherethrough the interior of the holder (3) communicates with the gas feeding pipe (13) secured in the casing (1) through the support insulator (17). Interposed between mechanical filters (16) and between holder (3) and pipe (13) is a getter (15).
Abstract:
The present invention relates to a vacuum arc electron source having an anode and a cathode facing each other such that they produce a plasma (P) after an appropriate voltage difference has been applied between the anode and the cathode, an electron extractor device (30) and a material-retaining device arranged between the extractor device and the plasma source. According to the invention, the material-retaining device comprises, arranged in the electron extraction direction (F), at least one upstream baffle (10) and a downstream baffle (20) which are each electrically conducting and have apertures (16, 26) arranged in quincunx, such that when the baffles (10, 20) are adjusted a given potential, the plasma (P) does not extend to downstream of the downstream baffle (20).
Abstract:
A large-area electron source which can operate continuously, stably, and indefinitely in a poor vacuum environment. The source includes a glow discharge cathode, appropriately positioned with respect to a target anode, and a fine-mesh grid spaced from the cathode by a distance less than the mean free path length of electrons leaving the cathode, the grid being electrically biased to control the electron beam current over a wide range with only small grid voltage changes. An accelerating voltage applied to the cathode can be varied continuously from as low as a few hundred volts to 30 KeV or greater and the source will continue to operate satisfactorily. Further, the grid is made of a fine mesh wire of sufficiently small dimensions as to not be resolvable in the target plane. A further refinement of the device utilizes scanning coils to achieve additional uniformity of the incident beam at the target plane. The basic apparatus of the invention can be combined with other features, for use in shadow mask lithography, resist sensitivity measurement, lift off processing, and resist curing.
Abstract:
Apparatus and method for producing a plurienergetic electron beam source. The apparatus includes a housing which functions as an anode, the same having an electron emission window covered by an electron-transparent grid, a cathode body mounted within the housing and electrically isolated therefrom, the spacing between the cathode body and grid being sufficient to permit a gas discharge to be maintained between them having a plasma region substantially thinner than the cathode sheath region. The method involves the simultaneous feeding of gas between a cathode body and an anode grid, applying voltages of about 10 kV to 20 kV and regulating the gas feed rate and the voltage to maintain a discharge condition of the character described above.
Abstract:
A plasma electron source has an apertured cathode, and a housing for defining a cavity behind the aperture. A trigger electrode, in communication with the cavity, is responsive to a short-duration trigger pulse for establishing plasma in the cavity. The plasma is sustained in the cavity subsequent to the termination of the trigger pulse by a bias circuit, which biases the cavity at a relatively low voltage with respect to the cathode for a period of time much longer than the duration of the trigger pulse.