Abstract: An ion implanter performs ion implantation by irradiating a wafer having a notch at its outer peripheral region by an ion beam. In ion implanter, a twist angle adjustment mechanism is configured to adjust a twist angle, an aligner is configured to adjust an alignment angle, a wafer transfer device is configured to transfer the wafer between the aligner and the twist angle adjustment mechanism, an image processing device is configured to detect the twist angle of the wafer on the twist angle adjustment mechanism, and a control device is configured to carry out a twist control in which the wafer is rotated by the twist angle adjustment mechanism by an angle obtained from a first difference between the detected twist angle and the alignment angle and a second difference between the alignment angle and a target twist angle given as one of ion implantation conditions.

Abstract: Patterning effects on a substrate are reduced during radiation-based heating by filtering the radiation source or configuring the radiation source to produce radiation having different spectral characteristics. For the filtering, an optical filter may be used to truncate specific wavelengths of the radiation. The different configurations of the radiation source include a combination of one or more continuum radiation sources with one or more discrete spectrum sources, a combination of multiple discrete spectrum sources, or a combination of multiple continuum radiation sources. Furthermore, one or more of the radiation sources may be configured to have a substantially non-normal angle of incidence or polarized to reduce patterning effects on a substrate during radiation-based heating.

Abstract: A method and system for performing gas cluster ion beam (GCIB) etch processing of various materials is described. In particular, the GCIB etch processing includes setting one or more GCIB properties of a GCIB process condition for the GCIB to achieve one or more target etch process metrics.

Abstract: A method comprising introducing an injected gas (e.g., Argon, Xenon) into a beam line region comprising a magnetic scanner is provided herein. The injected gas improves beam current by enhancing (e.g., increasing, decreasing) charge neutralization of the magnetic ion beam (e.g., the ion beam at regions where the scanning magnetic field is non-zero) thereby reducing the current loss due to the zero field effect (ZFE). By reducing the current loss in regions having a magnetic field, the magnetic beam current is increased (e.g., the beam current is increased in regions where the magnetic field is non-zero) raising the overall beam current in a uniform manner over an entire scan path and thereby reducing the effect of the ZFE. In other words, the ZFE is removed by effectively minimizing it through an increase in the magnetized beam current.

Abstract: An ion source includes arc chamber housing defining an arc chamber. The arc chamber housing has an extraction plate in a fixed position, and the extraction plate defines a plurality of extraction apertures. The ion source also includes a shutter assembly positioned outside of the arc chamber proximate the extraction plate. The shutter assembly is configured to block at least a portion of one of the plurality of extraction apertures during one time interval. The ion source combined with relative movement of a workpiece to be treated with an ion beam extracted from the ion source enables a two dimensional ion implantation pattern to be formed on the workpiece using only one ion source.

Abstract: An ion source, a mass spectrometer and a method of enhancing the performance of an ion source for use with a mass spectrometer. The ion source has a housing incorporating an ion source enclosure defining a chamber and an outer cover remote from the chamber. A fluid flow passageway is provided between the ion source enclosure and the outer cover. The method of the invention comprising supplying to the ion source housing a regulated flow of fluid through the fluid passageways so as to maintain the ion source enclosure within a predetermined temperature range of substantially between 60° c. and 80° c. and preferably at 70° c.

Abstract: A high pressure microplasma source operating in a normal glow discharge regime is used to produce a cold bright focused beam of Xe+ and/or Xe2+ ions having ion temperature of the order of 0.5-1 eV and a current density on the order of 0.1-1 A/cm2 or higher for focused ion beam applications.

Abstract: Described herein is an ion slicer that: a) accelerates an ion beam towards a first electrode comprising an ion entrance slit, where the first electrode blocks a portion of ions with high displacement from the axis of the ion beam, thereby slicing the ion beam; and then b) decelerates the ion beam after it is sliced.

Abstract: A system and method are disclosed for controlling an ion beam. A deceleration lens is disclosed for use in an ion implanter. The lens may include a suppression electrode, first and second focus electrodes, and first and second shields. The shields may be positioned between upper and lower portions of the suppression electrode. The first and second shields are positioned between the first focus electrode and an end station of the ion implanter. Thus positioned, the first and second shields protect support surfaces of said first and second focus electrodes from deposition of back-streaming particles generated from said ion beam. In some embodiments, the first and second focus electrodes may be adjustable to enable the electrode surfaces to be adjusted with respect to a direction of the ion beam. By adjusting the angle of the focus electrodes, parallelism of the ion beam can be controlled. Other embodiments are described and claimed.

Abstract: An ion beam machining and observation method relevant to a technique of cross sectional observation of an electronic component, through which a sample is machined by using an ion beam and a charged particle beam processor capable of reducing the time it takes to fill up a processed hole with a high degree of flatness at the filled area. The observation device is capable of switching the kind of gas ion beam used for machining a sample with the kind of a gas ion beam used for observing the sample. To implement the switch between the kind of a gas ion beam used for sample machining and the kind of a gas ion beam used for sample observation, at least two gas introduction systems are used, each system having a gas cylinder a gas tube, a gas volume control valve, and a stop valve.

Abstract: A charged particle beam writing method includes inputting layout information of a plurality of chips on which pattern formation is to be achieved, setting, using the layout information, a plurality of writing groups each being composed of at least one of the plurality of chips and each having writing conditions differing from each other, setting a frame which encloses a whole of all chip regions in all the plurality of writing groups, virtually dividing the frame into a plurality of stripe regions in a predetermined direction while keeping chips of writing groups differing from each other intermingled, setting an order of each of the plurality of stripe regions such that a reference position of the each of the plurality of stripe regions is located in order in the predetermined direction, and writing a pattern in the each of the plurality of stripe regions onto a target workpiece according to the order which has been set, by using a charged particle beam.

Abstract: A device is disclosed for providing an inductively coupled radio frequency plasma flood gun. In one particular exemplary embodiment, the device is a plasma flood gun in an ion implantation system. The plasma flood gun may comprise a plasma chamber having one or more apertures; a gas source capable of supplying at least one gaseous substance to the plasma chamber; a single-turn coil disposed within the plasma chamber, and a power source coupled to the coil for inductively coupling radio frequency electrical power to excite the at least one gaseous substance in the plasma chamber to generate a plasma. The inner surface of the plasma chamber may be free of metal-containing material and the plasma may not be exposed to any metal-containing component within the plasma chamber. The plasma chamber may include a plurality of magnets for controlling the plasma.

Abstract: Techniques for improving extracted ion beam quality using high-transparency electrodes are disclosed. In one particular exemplary embodiment, the techniques may be realized as an apparatus for ion implantation. The apparatus may comprise an ion source for generating an ion beam, wherein the ion source comprises a faceplate with an aperture for the ion beam to travel therethrough. The apparatus may also comprise a set of extraction electrodes comprising at least a suppression electrode and a high-transparency ground electrode, wherein the set of extraction electrodes may extract the ion beam from the ion source via the faceplate, and wherein the high-transparency ground electrode may be configured to optimize gas conductance between the suppression electrode and the high-transparency ground electrode for improved extracted ion beam quality.

Abstract: An improved method of producing solar cells utilizes a mask which is fixed relative to an ion beam in an ion implanter. The ion beam is directed through a plurality of apertures in the mask toward a substrate. The substrate is moved at different speeds such that the substrate is exposed to an ion dose rate when the substrate is moved at a first scan rate and to a second ion dose rate when the substrate is moved at a second scan rate. By modifying the scan rate, various dose rates may be implanted on the substrate at corresponding substrate locations. This allows ion implantation to be used to provide precise doping profiles advantageous for manufacturing solar cells.

Abstract: A particle isolation system includes a semiconductor process chamber; at least one member within the semiconductor process chamber wherein the member has at least a first position and a second position; and at least one isolation compartment having a plurality of walls, the isolation compartment defined by the plurality of walls, at least one of the plurality of walls of the isolation compartment defining at least one opening wherein the member in the first position permits particles to enter the isolation compartment from the semiconductor process chamber through the opening, and wherein the member in the second position substantially encloses the isolation compartment thereby substantially retaining the particles in the isolation compartment and substantially limiting movement of the particles between the semiconductor process chamber and the isolation compartment through the opening. An ion implant system is also provided.

Abstract: Ion sources, systems and methods are disclosed. In some embodiments, the ion sources, systems and methods can exhibit relatively little undesired vibration and/or can sufficiently dampen undesired vibration. This can enhance performance (e.g., increase reliability, stability and the like). In certain embodiments, the ion sources, systems and methods can enhance the ability to make tips having desired physical attributes (e.g., the number of atoms on the apex of the tip). This can enhance performance (e.g., increase reliability, stability and the like).

Abstract: A processing system may include a plasma source for providing a plasma and a workpiece holder arranged to receive ions from the plasma. The processing system may further include a pulsed bias circuit electrically coupled to the plasma source and operable to switch a bias voltage supplied to the plasma source between a high voltage state in which the plasma source is biased positively with respect to ground and a low voltage state in which the plasma source is biased negatively with respect to the ground.

Abstract: Blockers in an ion beam blocker unit selectively block or trim an ion beam. In one instance, the ion beam has first current regions and second current regions. These current regions may be unequal. The ion beam is then implanted into a workpiece to form regions with different doses. The workpiece may be scanned so that the entirety of its surface is implanted.

Abstract: A method for evaluating radiation model data in particle beam radiation applications, in particular in proton beam therapy of a determined target volume of malignant tissue within a patient, includes the following steps: a) gaining diagnostic data for a determined target volume to be irradiated; b) calculating a particle range in the predetermined target volume based on the diagnostic data for the determined target volume; c) designing a radiation model with particle beam characteristics based on the calculated particle range and optionally on a calculated dose depth distribution; d) applying a single pencil beam shot to the determined target volume at an elevated beam energy as compared to the particle beam characteristics of the radiation model; e) measuring the beam range of the single pencil beam shot downstream of the determined target volume; and f) comparing the measured beam range to a reference beam range calculated on the basis of the radiation model.

Abstract: An object of the present invention relates to realizing the processing of a sample by charged particle beams and the monitoring of the processed cross-section with a high throughput. It is possible to process an accurate sample without an intended region lost even when the location and the size of the intended region are unknown by: observing a cross-sectional structure being processed by FIBs by using a secondary particle image generated from a sample by the ion beams shaving a cross section; forming at least two cross sections; and processing the sample while the processing and the monitoring of a processed cross section are carried out.

Abstract: An improved method and apparatus for imaging and milling a substrate using a FIB system. Preferred embodiments of the present invention use a mixture of light and heavy ions, focused to the same focal point by the same beam optics, to simultaneously mill the sample surface (primarily with the heavy ions) while the light ions penetrate deeper into the sample to allow the generation of images of subsurface features. Among other uses, preferred embodiments of the present invention provide improved methods of navigation and sample processing that can be used for various circuit edit applications, such as backside circuit edit.

Abstract: The ion implanter includes lens elements that arrange unit lens elements along a direction of a beam width of a ribbon ion beam and regulate a magnetic field or electric field to be created by each unit lens element in order to regulate a current density distribution of the ion beam, and a controlling portion that sets the intensity of the magnetic field or electric field to be created by the unit lens element to be regulated by the lens elements in accordance with the measured current density distribution.

Abstract: An ion source includes an arc chamber housing defining an arc chamber having an extraction aperture, and a wiper. The wiper is positioned within the arc chamber in a parked position and configured to be driven from the parked position to operational positions to clean the extraction aperture. A cleaning sub-assembly for an ion source includes a wiper configured to be positioned within an arc chamber of the ion source when in a parked position and driven from the parked position to operational positions to clean an extraction aperture of the ion source.

Abstract: In an ion implanter, a detector assembly is employed to monitor the ion beam current and incidence angle at the location of the work piece or wafer. The detector assembly includes a plurality of pairs of current sensors and a blocker panel. The blocker panel is coupled to the detector array to move together with the detector array. The blocker panel is also disposed a distance away from the sensors to allow certain of the beamlets that comprise the ion beam to reach the sensors. Each sensor in a pair of sensors measures the beam current incident thereon and the incident angle is calculated using these measurements. In this manner, beam current and incidence angle variations may be measured at the work piece site and be accommodated for, thereby avoiding undesirable beam current profiles.

Abstract: In an ion implanter, an ion current measurement device is disposed behind a mask co-planarly with respect to a surface of a target substrate as if said target substrate was positioned on a platen. The ion current measurement device is translated across the ion beam. The current of the ion beam directed through a plurality of apertures of the mask is measured using the ion current measurement device. In this manner, the position of the mask with respect to the ion beam as well as the condition of the mask may be determined based on the ion current profile measured by the ion current measurement device.

Abstract: An ion implanter and an ion implant method are disclosed. Essentially, the wafer is moved along one direction and an aperture mechanism having an aperture is moved along another direction, so that the projected area of an ion beam filtered by the aperture is two-dimensionally scanned over the wafer. Thus, the required hardware and/or operation to move the wafer may be simplified. Further, when a ribbon ion beam is provided, the shape/size of the aperture may be similar to the size/shape of a traditional spot beam, so that a traditional two-dimensional scan may be achieved. Optionally, the ion beam path may be fixed without scanning the ion beam when the ion beam is to be implanted into the wafer, also the area of the aperture may be adjustable during a period of moving the aperture across the ion beam.

Abstract: A method for performing milling and imaging in a focused ion beam (FIB) system employing an inductively-coupled plasma ion source, wherein two sets of FIB system operating parameters are utilized: a first set representing optimized parameters for operating the FIB system in a milling mode, and a second set representing optimized parameters for operating in an imaging mode. These operating parameters may comprise the gas pressure in the ICP source, the RF power to the ICP source, the ion extraction voltage, and in some embodiments, various parameters within the FIB system ion column, including lens voltages and the beam-defining aperture diameter. An optimized milling process provides a maximum milling rate for bulk (low spatial resolution) rapid material removal from the surface of a substrate. An optimized imaging process provides minimized material removal and higher spatial resolutions for improved imaging of the substrate area being milled.

Abstract: A multipurpose ion implanter beam line configuration comprising a mass analyzer magnet followed by a magnetic scanner and magnetic collimator combination that introduce bends to the beam path, the beam line constructed for enabling implantation of common monatomic dopant ion species cluster ions, the beam line configuration having a mass analyzer magnet defining a pole gap of substantial width between ferromagnetic poles of the magnet and a mass selection aperture, the analyzer magnet sized to accept an ion beam from a slot-form ion source extraction aperture of at least about 80 mm height and at least about 7 mm width, and to produce dispersion at the mass selection aperture in a plane corresponding to the width of the beam, the mass selection aperture capable of being set to a mass-selection width sized to select a beam of the cluster ions of the same dopant species but incrementally differing molecular weights, the mass selection aperture also capable of being set to a substantially narrower mass-selection

Abstract: A charged particle beam writing apparatus includes a plurality of tracking calculation units to calculate a deflection amount of the charged particle beam in regard to a movable substrate, a switching unit for each of a plurality of virtual small regions of the substrate, to input an end signal indicating completion of charged particle beam emission to a respective small region, and to switch from output of one of the tracking calculation units to output of another of the tracking calculation units, and a deflector, while a substrate is moving, to deflect the charged particle beam to an n-th small region, based on an output from one of the tracking calculation units before switching and to deflect the charged particle beam to an (n+1)th small region based on an output from another of tracking calculation units after switching the plurality of tracking calculation units.

Abstract: During ion implantation into a wafer, an ion beam current is measured, a change in vacuum conductance which changes in accordance with a change of the location of a structure operating in a vacuum beam line chamber or a vacuum treatment chamber is obtained, furthermore, changes in degree of vacuum at one or plural places are detected using a vacuum gauge installed in the vacuum beam line chamber or the vacuum treatment chamber. The amount of an ion beam current is corrected using the obtained vacuum conductance and the detected degree of vacuum at one or plural places, and the dose amount implanted into the wafer is controlled.

Abstract: The present invention relates to a method and apparatus for varying the cross-sectional shape of an ion beam, as the ion beam is scanned over the surface of a workpiece, to generate a time-averaged ion beam having an improved ion beam current profile uniformity. In one embodiment, the cross-sectional shape of an ion beam is varied as the ion beam moves across the surface of the workpiece. The different cross-sectional shapes of the ion beam respectively have different beam profiles (e.g., having peaks at different locations along the beam profile), so that rapidly changing the cross-sectional shape of the ion beam results in a smoothing of the beam current profile (e.g., reduction of peaks associated with individual beam profiles) that the workpiece is exposed to. The resulting smoothed beam current profile provides for improved uniformity of the beam current and improved workpiece dose uniformity.

Abstract: An ion implantation device and a method of manufacturing a semiconductor device is described, wherein ionized boron hydride molecular clusters are implanted to form P-type transistor structures. For example, in the fabrication of Complementary Metal-Oxide Semiconductor (CMOS) devices, the clusters are implanted to provide P-type doping for Source and Drain structures and for Polygates; these doping steps are critical to the formation of PMOS transistors. The molecular cluster ions have the chemical form BnHx+ and BnHx?, where 10?n?100 and 0?x?n+4.

Abstract: An multi-ion beam implantation apparatus and method are disclosed. An exemplary apparatus includes an ion beam source that emits at least two ion beams; an ion beam analyzer; and a multi-ion beam angle incidence control system. The ion beam analyzer and the multi-ion beam angle incidence control system are configured to direct the emitted at least two ion beams to a wafer.

Abstract: An apparatus includes a process chamber configured to perform an ion implantation process. A cooling platen or electrostatic chuck is provided within the process chamber. The cooling platen or electrostatic chuck is configured to support a semiconductor wafer. The cooling platen or electrostatic chuck has a plurality of temperature zones. Each temperature zone includes at least one fluid conduit within or adjacent to the cooling platen or electrostatic chuck. At least two coolant sources are provided, each fluidly coupled to a respective one of the fluid conduits and configured to supply a respectively different coolant to a respective one of the plurality of temperature zones during the ion implantation process. The coolant sources include respectively different chilling or refrigeration units.

Abstract: A focused ion beam apparatus, including: a specimen transferring unit having a probe to which a micro-specimen extracted from a specimen, can be joined through a joining deposition film, for transferring the micro-specimen to a sample holder; and wherein, the specimen transferring unit holds the probe which is joined through the joining deposition film to the micro-specimen extracted from the specimen, and the sample stage moves so that the sample holder mounted on the holder clasp is provided into an irradiated range of the focused ion beam, and the specimen transferring unit approaches the probe to the sample holder, and the gas nozzle supplies the deposition gas so that the micro-specimen is fixed to the sample holder through a fixing deposition film, and the ion beam irradiating optical system irradiates the focused ion beam to the micro-specimen fixed to the sample holder for various procedures.

Abstract: The present invention provides a plasma ion beam system that includes multiple gas sources and that can be used for performing multiple operations using different ion species to create or alter submicron features of a work piece. The system preferably uses an inductively coupled, magnetically enhanced ion beam source, suitable in conjunction with probe-forming optics sources to produce ion beams of a wide variety of ions without substantial kinetic energy oscillations induced by the source, thereby permitting formation of a high resolution beam.

Abstract: An ion implanter has a beam deflector having a pair of magnetic poles facing each other in a z direction, insulating members provided on the respective magnetic poles, at least one pair of electrodes provided on the insulating members so as to face each other across a space through which the ion beam passes in the z direction, and at least one power source configured to apply a voltage to the pair of electrodes. The beam deflector is configured to deflect, by a magnetic field, an overall shape of the ion beam so as to be substantially parallel to the x direction. The pair of electrodes have a dimension longer than the dimension of the ion beam in the y direction, and constitute an asymmetrical einzel lens in the direction of travel of the central orbit of the ion beam.

Abstract: A dual beam system includes an ion beam system and a scanning electron microscope with a magnetic objective lens. The ion beam system is adapted to operate optimally in the presence of the magnetic field from the SEM objective lens, so that the objective lens is not turned off during operation of the ion beam. An optional secondary particle detector and an optional charge neutralization flood gun are adapted to operate in the presence of the magnetic field. The magnetic objective lens is designed to have a constant heat signature, regardless of the strength of magnetic field being produced, so that the system does not need time to stabilize when the magnetic field is changed.

Abstract: A charged particle gun includes: a charged particle source; a first extracting electrode arranged in such a manner that a distance between the charged particle source and the first extracting electrode is fixed; a second extracting electrode located on the side opposite to the charged particle source with respect to the first extracting electrode, the electrode being arranged in such a manner that a distance between the first extracting electrode and the second extracting electrode is adjustable; and an earth electrode located on the side opposite to the first extracting electrode with respect to the second extracting electrode, the electrode being arranged in such a manner that a distance between the second extracting electrode and the earth electrode is fixed; wherein the first extracting electrode is equal in potential to the second extracting electrode.

Abstract: An ion implantation system and process, in which the performance and lifetime of the ion source of the ion implantation system are enhanced, by utilizing isotopically enriched dopant materials, or by utilizing dopant materials with supplemental gas(es) effective to provide such enhancement.

Abstract: Ion microscope methods and systems are disclosed. In general, the systems and methods involve relatively light isotopes, minority isotopes or both. In some embodiments, He-3 is used.

Abstract: When positively charged ions are implanted into a target substrate, charge-up damage may occur on the target substrate. In order to suppress charge-up caused by secondary electrons emitted from the target substrate when positively charged ions are implanted, a conductive member is installed at a position facing the target substrate and electrically grounded with respect to a high frequency. Further, a field intensity generated in the target substrate may be reduced by controlling an RF power applied to the target substrate in pulse mode.

Abstract: An apparatus and a method of ion implantation using a rotary scan assembly having an axis of rotation and a periphery. A plurality of substrate holders is distributed about the periphery, and the substrate holders are arranged to hold respective planar substrates. Each planar substrate has a respective geometric center on the periphery. A beam line assembly provides a beam of ions for implantation in the planar substrates on the holders. The beam line assembly is arranged to direct said beam along a final beam path.

Abstract: An ion implanting apparatus includes: an electrostatic accelerating tube for causing an ion beam extracted from an ion source to have a desirable energy, and deflecting the ion beam to be incident on a target, the electrostatic accelerating tube including deflecting electrodes provided to interpose the ion beam therebetween. The deflecting electrodes include a first deflecting electrode and a second deflecting electrode to which different electric potentials from each other are set. The second deflecting electrode is provided on a side where the ion beam is to be deflected and includes an upstream electrode provided on an upstream side of the ion beam and a downstream electrode provided apart from the upstream electrode toward a downstream side. An electric potential of the upstream electrode and an electric potential of the downstream electrode are independently set from each other.

Abstract: Disclosed are embodiments of an ion beam sample preparation thermal management apparatus and methods for using the embodiments. The apparatus comprises an ion beam irradiating means in a vacuum chamber that may direct ions toward a sample, a shield blocking a portion of the ions directed toward the sample, and a shield retention stage with shield retention means that replaceably and removably holds the shield in a position. The shield has datum features which abut complementary datum features on the shield retention stage when the shield is held in the shield retention stage. The shield has features which enable the durable adhering of the sample to the shield for processing the sample with the ion beam. The complementary datum features on both shield and shield retention stage enable accurate and repeatable positioning of the sample in the apparatus for sample processing and reprocessing. A heat sink means is configured to conduct heat away from the sample undergoing sample preparation in the ion beam.

Abstract: A mask or set of masks is disclosed in which outward projections are placed on either side of at least one aperture. An ion beam is then directed through the mask toward a workpiece. An ion collecting device or an optical system is then used to measure the alignment of the mask to the ion beam. These projections serve to increase the sensitivity of the system to misalignment. In another embodiment, a blocker is used to create a region of the workpiece that is not subjected to a blanket implant. This facilitates the use of optical means to insure and determine alignment of the mask to the ion beam.

Abstract: One embodiment relates to an ion implanter. The ion implanter includes an ion source to generate an ion beam, as well as a scanner to scan the ion beam across a surface of a workpiece along a first axis. The ion implanter also includes a deflection filter downstream of the scanner to ditheredly scan the ion beam across the surface of the workpiece along a second axis.

Abstract: An ion implantation method and the like by which a circular implantation region and a peripheral implantation region surrounding it and the dose amount of which is different from that of the circular implantation region can be formed within the surface of the substrate without the use of the step rotation of the substrate. The ion implantation method is forms a circular implantation region and a peripheral implantation region surrounding it and a dose amount of which is different from that of the circular implantation region within a surface of the substrate by making variable a scanning speed of the ion beam 4 within the surface of the substrate and changing a scanning speed distribution, in an X direction, of the ion beam within the surface of the substrate for each one-way scanning or each reciprocative scanning, according to a position of the substrate in a Y direction.

Abstract: The present invention relates to a multi-beamlet multi-column particle-optical system comprising a plurality of columns which are disposed in an array for simultaneously exposing a substrate, each column having an optical axis and comprising: a beamlet generating arrangement comprising at least one multi-aperture plate for generating a pattern of multiple beamlets of charged particles, and an electrostatic lens arrangement comprising at least one electrode element; the at least one electrode element having an aperture defined by an inner peripheral edge facing the optical axis, the aperture having a center and a predetermined shape in a plane orthogonal to the optical axis; wherein in at least one of the plurality of columns, the predetermined shape of the aperture is a non-circular shape with at least one of a protrusion and an indentation from an ideal circle about the center of the aperture.

Abstract: A high voltage insulator and radiation shield made of barium sulfate composite having a polymer matrix and barium sulfate therein. The device may be made by casting. By means of use of various combinations of barium sulfate, other radiologically resistant materials, polymers, and third components, the physical, radiological and electrical properties of the finished products may be tailored to achieve desired properties. In addition, the invention teaches that radiation shielding, insulators, and combined radiation shield/insulators may be fashioned from the composite. A wide range of production methods may be employed, including but not limited to liquid resin casting.