Abstract:
A method of transporting gas and entrained ions between higher and lower pressure regions of a mass spectrometer comprises providing an ion transfer conduit 60 between the higher and lower pressure regions. The ion transfer conduit 60 includes an electrode assembly 300 which defines an ion transfer channel. The electrode assembly 300 has a first set of ring electrodes 305 of a first width D1, and a second set of ring electrodes of a second width D2 (≧D1) and interleaved with the first ring electrodes 305. A DC voltage of magnitude V1 and a first polarity is supplied to the first ring electrodes 205 and a DC voltage of magnitude V2 which may be less than or equal to the magnitude of V1 but with an opposed polarity is applied to the second ring electrodes 310. The pressure of the ion transfer conduit 60 is controlled so as to maintain viscous flow of gas and ions within the ion transfer channel.
Abstract:
A multi-reflecting ion optical device includes electrostatic field generating means configured to generate electrostatic field defined by a superposition of first and second distributions of electrostatic potential φEF, φLS. The first distribution φEF subjects ions to energy focusing in a flight direction and the second distribution φLS subjects ions to stability in one lateral direction, to stability in another lateral direction for the duration of at least a finite number of oscillations in the one lateral direction and to subject ions to energy focusing in the one lateral direction for a predetermined energy range.
Abstract:
An apparatus for producing negative ions including an emitter coated with an ionic liquid room-temperature molten salt, an electrode positioned downstream relative to the emitter, a power supply that applies a voltage to the emitter with respect to the electrode. The power supply is sufficient to generate a stable high brightness beam of negative ions having minimal chromatic and spherical aberrations in the beam. An electrostatic lens and deflector is used to focus and direct the beam to a target.
Abstract:
An electron-emitting device utilizes an emitter electrode (12) shaped like a ladder in which a line of emitter openings (18) extend through the electrode. In fabricating the device, the emitter openings can be utilized to self-align certain edges, such as edges (38C) of a focusing system (37), to other edges, such as edges (28C) of control electrodes (28), to obtain desired lateral spacings. The self-alignment is typically achieved with the assistance of a backside photolithographic exposure operation. The ladder shape of the emitter electrode also facilitates the removal of short-circuit defects involving the electrode.
Abstract:
In a method of operating an electron tube including a plurality of emitters formed on a substrate and having sharp tips, gate electrodes surrounding the plurality of emitters, and a peripheral electrode surrounding an electron emission region constituted by the plurality of emitters and the gate electrodes and insulated from the plurality of emitters and the gate electrodes, the voltage applied to the peripheral electrode is set to be lower than the voltage applied to the gate electrode.
Abstract:
An electron-emitting device utilizes an emitter electrode (12) shaped like a ladder in which a line of emitter openings (18) extend through the electrode. In fabricating the device, the emitter openings can be utilized to self-align certain edges, such as edges (38C) of a focusing system (37), to other edges, such as edges (28C) of control electrodes (28), to obtain desired lateral spacings. The self-alignment is typically achieved with the assistance of a backside photolithographic exposure operation. The ladder shape of the emitter electrode also facilitates the removal of short-circuit defects involving the electrode.
Abstract:
A field-emission cold-cathode device including a substrate, an emitter having a sharp distal, a gate electrode having a hole in a region of the distal end of the emitter, and a focusing electrode formed farther from the distal end of the emitter than the gate electrode in a region of an end portion near the emitter.
Abstract:
In a field emission cathode, periphery portions of opening portions of a gate electrode are recessed on a side of a substrate, and a focusing electrode having opening portions which are identical in number with the opening portions of the gate electrode are disposed on the gate electrode. Further, a shield electrode having opening portions which are identical in number with opening portions of the gate electrode are disposed between the gate electrode and the focusing electrode. According to the above-mentioned construction, a focusing aberration can be reduced, and a focused electron flow can be obtained by a low electric potential of the gate electrode.
Abstract:
A combined fine focusing micro lens array and micro deflector assembly for use in electron beam tubes of the fly's eye type is provided. The assembly comprises a fine focusing micro lens array sub-assembly formed from a plurality of spaced-apart stacked parallel thin planar apertured silicon semiconductor lens plates each having an array of micro lens aperture openings. The lens plates each have highly conductive surfaces and are secured to glass rods for holding the plates in stacked parallel spaced-apart relationship with the apertures axially aligned in parallel. A micro deflector assembly is adjacent to the micro lens array sub-assembly. A micro deflector element axially aligned with each respective fine focusing lens element serves for deflecting an electron beam passing through along orthogonal x-y directional axes of movement normal to the electron beam path. The deflector elements are comprised by two orthogonally arrayed sets of parallel spaced-apart deflector bars with alternate bars of each set of deflector bars being interconnected electrically for common connection to a respective source of fine x-y deflection potential.The thin planar apertured silicon lens plates comprising the micro lens array are held together in stacked parallel assembled relationship by spaced-apart glass support rods whose longitudinal axes extend at right angles to the plates and to which the planar silicon lens plates are secured at their periphery. The two orthogonally arrayed sets of parallel spaced-apart deflection bars forming the sets of micro-deflector elements likewise preferably comprise parallel plates or bars of polycrystalline silicon having a highly conductive metalized surface. The micro deflector bars likewise are held in assembled spaced-apart parallel relationship by respective sets of spaced-apart parallel supporting glass rods whose longitudinal axes extend in a plane parallel to the plane of the deflector bars but at right angles thereto and to which the ends of the deflector bars are thermally bonded. The fine focusing micro lens array and micro deflector sub-assembly thus comprised, are secured together in assembled relation by additional glass support rods being disposed about the outer peripheries of the micro lens and micro deflector sub-assemblies and being secured thereto by thermal bonding such as by fusion.
Abstract:
Electric fields for electrostatic optics for focusing or otherwise controlling beams of ions, electrons and charged particles in general produced by surface current distributions which flow on appropriately shaped and located resistive elements from electrical power sources of appropriate voltage connected to two or more points or regions of the resistive surfaces; the resulting electric fields in the proximity of the current carrying surfaces are parallel to these surfaces. Useful electric field configurations may be produced which are inconvenient or impossible to produce by the prior art using surface charge distributions. New and improved analyzers of "concentric hemisphere" and "parallel plate" types are specifically utilized for ion kinetic energy selection prior to measurement of the mass-to-charge ratio of secondary ions produced by primary ion bombardment of surfaces.