Abstract: A universal canister flush valve having a valve body configured to be fixed relative to a toilet tank and having a hollow wall defining an internal flow passage; a guide post coupled to and extending away from the valve body; a float fitted about and configured to slide relative to the guide post between a closed position and an open position, the float having an open top; and an extender that selectively couples to the open top in a first position, in which a first end of the extender is received in and coupled to the open top, and in a second position, in which a second end of the extender is received in and coupled to the open top, wherein the extender and float define a first overflow height in the first position and define a second overflow height in the second position.

Abstract: The present invention is directed to an assembly for stretching a body cavity to a predetermined shape. The assembly includes an inelastic balloon that is affixed to the distal end of a balloon-tube. The tube defines an interior channel extending along a central axis that is contiguous with the interior of the balloon such that inflation and deflation of the balloon is controllable from the proximal end of the tube. When inflated the balloon defines a predetermined surface contour disposed about an interior region extending along a balloon axis. An alignment device operative from the proximal end of the tube provides for selectively aligning the central and balloon axes to a predetermined angular orientation.

Abstract: A phantom apparatus for measuring the radiation dose distribution produced by a brachytherapy device used to treat a localized area with radiation. The brachytherapy device includes an insertable probe capable of producing predefined radiation dose geometries about a predefined point. The phantom apparatus includes a tank containing a medium having a radiological equivalent characteristic of the localized area to be treated. The phantom apparatus also includes a radiation sensor for measuring the radiation dose and a positioning system for moving the probe with respect to the radiation sensor. The radiation sensor is also coupled to a positioning system to orient the sensor for optimal dose measurements. The phantom apparatus includes a control system that coordinates the movements of the probe and the radiation sensor to avoid a collision. The control system moves the probe along a predefined path around radiation sensor and records the dose at predefined points along the path.

Abstract: The present invention is directed to an x-ray source for irradiating a surface defining a body cavity in accordance with a predetermined dose distribution. The source comprises a housing, an elongated tubular probe, a target assembly, and an inflatable balloon. The housing encloses an electron beam source and includes elements for generating an electron beam along a beam path. The tubular probe extends along a central axis from the housing about the beam path. The target assembly extends along the central axis and is coupled to the end of the probe distal from the housing. The target assembly includes a target element is positioned in the beam path. The target element is adapted to emit x-rays in response to electrons incident thereon from the beam. The probe tip assembly and associated control electronics include elements for positioning the target element in the beam path, and is substantially x-ray transparent.

Abstract: The present invention is directed to a kit for delivering x-rays to the interior surface of a body cavity. The kit includes an x-ray source and an x-ray source guidance tube. The guidance tube includes an inflatable inelastic balloon disposed about and affixed at its distal end such that when inflated, the central axis of the balloon is coaxial with and is disposed about the central axis of the tubular element. Inflation and deflation of the balloon is controllable from the proximal end of the tubular element. The x-ray source may include an electron activated target for generating x-rays in response to electrons incident on the target. The x-ray source may also includes means for generating an electron beam and steering the beam so that it is incident on the target. The target end is slidably positionable within an interior channel of the source guidance tube.

Abstract: A method of treating brain tumors in a patient, comprising the steps of: identifying and locating a brain tumor in vivo; implanting at least a portion of an adjustable x-ray source in the patient proximate to the tumor, where the x-ray source generates an electron beam along a path on or slightly offset from a central axis to an x-ray emitting target element; and controlling the x-ray source to generate an x-ray pattern to selectively irradiate the tumor. Also disclosed is a method and apparatus for detecting certain x-ray photons generated by the x-ray source and propagating back on a path which is along or slightly off-set from the central axis of the implanted radiation source.

Abstract: A method of treating brain tumors in a patient, comprising the steps of: identifying and locating a brain tumor in vivo by affixing a stereotactic frame to the head of the patient, performing a computer tomographic (CT) scan of the skull of the patient to determine the location, size, and shape of the tumor with respect to the stereotactic frame, performing a biopsy by inserting an extraction tool along a path measured with respect to the frame to the tumor location, extracting a tissue from the location, removing the needle and the extracted tissue and analyzing the tissue; implanting at least a portion of an adjustable x-ray radiation source in the patient proximate the tumor, the adjustable radiation source including an electron beam source outside the head of the patient, and directing an electron beam produced by the source outside the head of the patient along the path to the location; and controlling the source to generate an x-ray radiation pattern characterized by a spatial and temporal distribution,

Abstract: This invention is directed to an x-ray source comprising a housing, an elongated tubular probe, a target assembly, and a beam steering assembly. The housing encloses an electron beam source, and has elements for generating an electron beam along a beam path. The elongated tubular probe extends along a central axis from the housing about the beam path. The target assembly extends along the central axis and is adapted for coupling to the end of the probe distal form the housing. The target assembly includes a target element positioned along the beam path, wherein the target element is adapted to emit x-rays in a predetermined spectral range in response to incident electrons. The beam steering assembly includes a deflection element, a feedback network, and a deflection controller. The deflection element deflects the beam from a nominal axis to a selected surface region on the target element in response to a deflection control signal.

Abstract: The present invention is directed to an x-ray source for irradiating a volume in accordance with a predetermined dose distribution. The source comprises a housing, an elongated tubular probe, and a target assembly. The housing encloses an electron beam source and includes elements for generating an electron beam along a beam path. The tubular probe extends along a central axis from the housing about the beam path. The target assembly extends along the central axis and is adapted for coupling to the end of the probe distal from the housing. The target assembly includes a target element, a probe tip assembly, and a variable transmission shield. The target element is positioned in the beam path. The target element is adapted to emit x-rays in response to electrons incident thereon from the beam. The probe tip assembly and associated control electronics include elements for positioning the target element in the beam path, and is substantially x-ray transparent.

Abstract: A light switched electron beam source employing a common photo-emitter cathode and at least two light emitting sources of monochromatic light, such as laser diodes, light emitting diodes and the like. A light optical collimating and aperture sub-system transmits the light images from the two or more light emitting sources onto a prism or other optical element for diverting the path of the light images onto a common path. The common photo-emitting cathode is positioned in the common path for selective excitation by the respective light emitting sources. An electron optical subsystem is coupled to the output from the common photo-emitter cathode for collimating and further sharpening the electron beam pattern and for projecting it upon a target plane which may comprise an integrated circuit structure upon which patterns are to be written.

Abstract: A method and apparatus for in-situ cleaning of charged particle beam optical systems such as electron microscopes, electron beam lithography systems, ion beam microscopes or lithography systems, through the use of a specially introduced plasma forming gas such as hydrogen that is excited by applying a high voltage, high frequency excitation potential between various optical elements of the electron beam optical column. Alternately, specially constructed separate plasma forming electrodes can be built into the electron beam optical system for this purpose. During the cleaning operation the plasma reacts chemically with the contaminants previously formed on the surface of the electron beam column optical elements to form gaseous reactants which then are pumped out of the electron beam column system.

Abstract: Resist coating on the surface of a semiconductor wafer is removed by a one-step process using anisotropic reactive ion etching through an apertured stencil disposed close to but spaced from the resist-coated surface. The ion bombardment greatly enhances the plasma etch rate in the areas of the coating exposed through stencil apertures so that only the exposed areas are effectively etched during the limited exposure time in spite of the presence of chemically reactive gas between the stencil and other areas of the wafer surface. The technique is limited by low resolution but is ideally suited for clearing resist from atop fiducial marks used to align the wafer with multiple wafers in an integrated circuit chip.

Abstract: An electron-beam array lithography (EBAL) system and method of operation is described. The method comprises deriving fiducial marking signals from a lenslet stitching grid of fiducial elements formed on a standard stitching target for calibrating the boundaries of the fields of view of the respective lens elements of an array of lenslets. The fiducial marking signals are used to stitch together the individual fields of view of the lens elements in the array of lenslets in order to cover a desired area of a workpiece surface to be subsequently exposed to the electron beam, for example, the surface of a semiconductor wafer upon which a plurality of integrated circuit chips are to be formed. In order to register the levels of multi-level patterns written on the same chip, each chip is provided with a registration fiducial grid comprised of fiducial marks at the corners and only at the corners of the chips.

Abstract: An electron-beam array lithography (EBAL) system and method of operation which employs an electron beam column of the array optics type having an array lens assembly, an array fine deflector assembly and a coarse deflector assembly, is described. The method and system derives fiducial marking signals from a lenslet stitching grid of fiducial elements, formed on a standard stitching target, for calibrating the boundaries of the fields of view of the respective elements of the array of lenslets. The fiducial marking signals are used to stitch together the individual fields of view of the elements in the array of lenslets. The same stitching calibration target, a precise copy, or similar precisely mapped target is used to calibrate all of the exposure stations of a multi-station EBAL system with the result that any level of multi-level registered patterns can be exposed in any of the so calibrated EBAL exposure stations.

Abstract: A multi-channel EBAL apparatus and method of operation employing a plurality of parallel operated electron beam channels with each electron beam channel being of the fly's eye array optics type having an electron gun for producing an electron beam, an array lenslet assembly and an associated fine deflector assembly together with a coarse deflector for selectively directing the electron beam to a desired array lenslet within the array lenslet assembly. The associated fine deflector element thereafter directs the electron beam to a desired point on a target surface such as a target semiconductor wafer being processed by electron beam lithography. A common movable stage is provided for supporting the target wafer surfaces below the plurality of parallel operated electron beam channels and for moving the target surfaces in common relative to the array optics axes of all of the electron beam channels.

Abstract: A data recording and readback subsystem for digital computer systems employing random access electron beam memories having an electron beam write/read apparatus for recording data to be stored on a recording member that is subject to fatigue in the eventuality of excessive write/read storage operations at any given physical location on the recording member. The improved method and apparatus for data management comprising systematically permuting the physical location of data stored on the recording member, recording each permutation of the data, deriving signals representative of the number of permutation operations, and combining programmer initiated requests from the computer system central processing unit for data stored in the electron beam memory with the signals representative of the number of permutations to derive an actual physical address signal for application to the electron beam memory for recovery of the requested data.

Abstract: A new and improved microminiature field emission electron source and method of manufacturing is described using a single crystal semiconductor substrate. The substrate is processed in accordance with known integrated microelectronic circuit techniques to form a plurality of integral, single crystal semiconductor raised field emitter tips at desired field emission cathode sites on the surface of the substrate in a manner such that the field emitter tips are integral with the single crystal semiconductor substrate. An insulating layer and overlying conductive layer may be formed in the order named over the semiconductor substrate and provided with openings at the field emission site locations to form micro-anode structures for each field emitter tip.