Abstract: A radio-frequency type charged particle accelerator includes a RFQ accelerator and a rear stage RF accelerator both of which are contained in a single evacuated chamber. The RFQ accelerator has quadrupole electrodes positioned along a traveling path of the charged particle and bunches and accelerates a charged particle beam by receiving a radio-frequency power from a radio-frequency power source and resonating. The rear stage RF accelerator is disposed in a rear stage of the RFQ accelerator and accelerates or decelerates the energy of the charged particle beam accelerated by the RFQ accelerator by receiving the radio-frequency power from the radio-frequency power source and resonating. A separating plate is disposed in the single evacuated chamber to separate the RFQ accelerator from the rear stage RF accelerator so that the RFQ accelerator and the rear stage RF accelerator work independently of each other.

Abstract: An charged particle beam imaging system reduces aberrations affecting resolution at the workpiece where the aberrations are caused by interactions between the charged particles in the beam. The average distance between the particles at a crossover image in the illumination subsystem is increased by positioning an annular aperture at the crossover image.

Abstract: A method and apparatus for analyzing ions by determining times of flight including using a deflectron based daughter ion selector for selecting daughter ions. Parent ions generated in an ion source may fragment to form daughter ions. Daughter ions may further fragment to form grand daughter ions. By selecting a specific type of daughter ion from ions formed in the ion source, one may obtain a grand daughter ion spectrum. According to the present invention, a deflectron based daughter ion selector, in the form of two deflectron and a set of selection plates, is used as a daughter ion selector.

Abstract: Electrostatic particle-beam lenses using a concentric co-planar array of independently biased rings can be advantageous for some applications. Traditional electrostatic lenses often consist of axial series of biased rings, apertures, or tubes. The science of lens design has devoted much attention to finding axial arrangements that compensate for the substantial optical aberrations of the individual elements. Thus, as with multi-element lenses for light, a multi-element charged-particle lens can have optical behavior that is far superior to that of the individual elements. Transverse multiple-concentric-ring lenses achieve high performance, while also having advantages in terms of compactness and optical versatility.

Abstract: An ion implanter and an ion implanting method compatible for both positive and negative ions. The ion implanter has an ion extractor and a mass analyzer for deflecting ions, having one of a positive or negative charged state, in a predetermined direction regardless of the charged state of the ions. A polarity converter changes the flux direction of a magnetic field in the mass analyzer according to the charged state of the ions. Thus, shallow and deep impurity layers can be formed into wafers without changing ion implanters, such that BF.sup.+ as well as B.sup.+ or P.sup.+ can be implanted with a single ion implanter. As a result, the product yield of a semiconductor device can be improved.

Abstract: A linear accelerator for charged particles includes a plurality of accelerating stages in a linear arrangement along a central axis. Each accelerating stage has at least one passageway radially spaced from the central axis for transmitting a beam of charged particles. Electromagnetic wave energy is coupled to the accelerating stages to produce an accelerating electric field in a region of the passageway of each of the accelerating stages. Coupling circuits couple the electromagnetic wave energy between adjacent accelerating stages. Each accelerating stage may be configured as an annular accelerating cavity or as two or more accelerating cavities disposed around the central axis. The passageway may be configured as two or more discrete apertures or a single annular aperture. Beam bending devices may be used to direct the charged particle beam through the accelerator two or more times. The linear accelerator produces a high current, high energy charged particle beam.

Abstract: An improved particle lens has an axis that is shifted to follow the central ray of the beam as it is deflected through the lens creating, in effect, a variable curvilinear optical axis for the lens and introducing aberrations depending on the object size and the distance off the lens symmetry axis. These aberrations are corrected by a set of wire pairs perpendicular to the system axis to add a gradient of the z-component of the magnetic field by which aberrations are generated of the same type but opposite direction as those inherent in the system.

Abstract: In a method for correcting astigmatism and focusing in a charged particle optical lens-barrel, according to the invention, Fourier transformation data items are obtained, which indicate images obtained by scanning a sample with a charged particle beam when the focal distance of an objective lens is set to each of at least two different values. Then, the configuration of the section of the beam is determined on the basis of the difference between the data items, thereby performing astigmatism correction and focusing. As a result, a charged particle microscope can perform highly accurate astigmatism correction and focusing during observation, irrespective of the surface configuration of the sample or the beam section on the sample.

Abstract: An electrostatic-magnetic lens arrangement is for focusing charged particles as well as a charged particle beam device with such a lens arrangement which has a magnetic lens and an electrostatic lens incorporated into the magnetic lens, the magnetic lens being constructed as a single-pole lens.

Abstract: In a charged particle beam projection apparatus in which a plurality of areas are defined in a mask and a pattern in each area is projected in a corresponding area on a substrate such as a semiconductor wafer or the like, in order to reduce aberration caused by magnetic lens or deflectors when projecting the mask pattern onto the substrate, the positioning and dimensions of these magnetic lenses or the deflectors are set so that specific relationships are achieved, or a distortion in the mask pattern projected on the substrate is corrected in correspondence to the partitioned areas on the mask pattern.

Abstract: The present invention relates to a charged particle beam exposure apparatus, deflecting a charged particle beam formed into a predetermined shape by being passed through a predetermined transmission mask, and irradiating a predetermined location on the surface of a sample with the charged particle beam. The apparatus comprises: a mirror barrel through which the charged particle beam is passed; and an electrostatic deflector, provided in the mirror barrel, for deflecting the charged particle beam. The electrostatic deflector has a plurality of pairs of electrodes, which are made of a conductive material having carbon as a primary element and are embedded in an internal face of an insulating cylinder. The present invention also relates to a method for forming the electrostatic deflector.

Abstract: There is disclosed an apparatus for generating an electron beam in an electron microscope comprising an electron gun, a second anode located under the gun, an aperture plate having an aperture for limiting the electron beam, and a scattered electron-blocking member for limiting passage of the beam. The aperture plate is mounted in the beam passage formed in the second anode. The scattered electron-blocking member is located under the aperture plate. Electrons scattered at the edges of the aperture are blocked by the scattered electron-blocking member from colliding against the accelerator tube.

Abstract: A charged particle beam expander increases a diameter of a charged particle beam while increasing uniformity of an area energy distribution thereof. The charged particle beam expander has a first linear optics section receiving the charged particle beam from a particle accelerator and for forming the charged particle beam to have a generally circular cross-section and a non-linear optics section receiving the charged particle beam from the first linear optics section and for redistributing charged particles from a periphery of the charged particle beam toward a core thereof. The charged particle beam expander also has a second linear optics section receiving the charged particle beam from the non-linear optics section, the second linear optics section for increasing the diameter of the charged particle beam and for imaging the charged particle beam onto the target.

Abstract: A decelerating and focusing ion beam device is provided with an ion source, a focusing lens system having a plurality of focusing lenses and a multiple decelerating lens system having a plurality of decelerating lenses. It is possible to realize selective super-refined crystal growth and superficial etching with very high accuracy.

Abstract: A method for improving the alignment of an electron-beam through the optical axis of lenses in a lithographic system is described. The beam is nominally tilted through the center of the lens, and by using a plurality of deflectors the beam is pivoted through the center of the lens using a square wave toggle. The resolution of the beam is measured as it scans over a target, for both toggle states. The nominal tilt angle is chosen such that the resolution is identical for both toggle states. This technique does not rely on using an observation station, as it is common on TEMs, to view a magnified image of the specimen. Therefore, this technique can be used to align a beam that has been shifted off the optical axis, for instance, in a Variable-Axis-Lens lithography (VAL) system.

Abstract: An arrangement for masked beam lithography by means of electrically charged particles for the imaging of structures of a mask on a substrate arranged behind it, with a substantially punctiform particle source (Q) and an extraction system (Ex) for a specific type of charged particles which leave the source (Q) in the form of a divergent particle beam, and with an electrode arrangement (B, B', El.sub.1, El.sub.2, E.sub.3, . . . El.sub.n) for concentrating the divergent particle beam into a particle beam which is at least approximately parallel, by means of which an electrostatic acceleration field (E) is generated, the potential (U) of which in the beam direction has a constant gradient at least in parts and perpendicular to the beam direction is substantially constant at least within the beam cross-section. The electrode arrangement can be formed for example by a plurality of coaxial ring electrodes (El.sub.1, El.sub.2, El.sub.3, . . . El.sub.

Abstract: An in-lens type objective lens is separated into two parts along the plane perpendicular to the direction of electron or ion orbit, so that a target sample can placed between the upper part and the lower part of the lens. Coils for the two parts are serially connected so as to work as one coil. Each of the upper and lower parts of the lens is provided with a lens positioning device. If the in-lens type objective lens is of a three-piece electrostatic type, a structure is provided which enables a target sample to be placed between a first and second electrode group and the third electrode.

Abstract: There is disclosed a high-resolution magnetic-electrostatic compound objective lens for use in a scanning electron microscope, the objective lens having reduced spherical aberration and chromatic aberration. The lens comprises a substantially conically-shaped magnetic pole piece, a coil wound along the inner surface of the magnetic pole piece, a hollow insulator disposed along the inner surface of the coil and a high-resistivity film disposed along the inner surface of the insulator. When the coil is energized, an axially symmetrical magnetic field is produced inside the magnetic lens. The obtained axial magnetic flux density distribution has a peak near the bottom end of the magnetic pole piece. The principal plane of the magnetic lens is brought close to the specimen and results in smaller aberrations.

Abstract: An ion accelerator for use in an ion beam implanter. The accelerator forms milliampere beams of heavy ions such as boron and phosphorous in a configuration in which the terminal ion source is replaced by a neutral beam injector. The neutral beam is formed at ground by the conversion of a focused beam of positive ions to neutral ions in a charge exchange canal. The neutral beam so formed is stripped of one or more electrons in a gas or vapor filled canal in the high voltage terminal. A 180.degree. analyzing magnet located in the high voltage terminal analyzes and directs a selected charge state to an acceleration tube parallel to the neutral beam injection tube where the selected positive ions are accelerated to ground potential.

Abstract: To improve the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector. A glitch waveform generated during a step change in the output of a D/A converter at the preceding stage of the amplifier is anticipated and is cancelled out with a correction waveform. After the output of the D/A converter has settled, this output is sample-held and the step change is interpolated with a smoothing circuit. The deflection area is increased by positioning an electrostatic deflector offset around the optical axis relative to another electrostatic deflector, and the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turns. The alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area.

Abstract: The invention relates to methods and devices for the efficient and loss-free transfer of ions in moderate vacuum from a first location (a source) to a second location (a user).The invention consists of an arrangement, reaching from the first location to the second, of five pole rods (a pentapole) to which a five-phase radio frequency (RF) voltage is applied.

Abstract: A charged particle lens has an axis that is shifted to follow the central ray of the beam as it is deflected through the lens creating, in effect, a variable curvilinear optical axis for the lens and introducing aberrations having depending on the object size and the distance off the lens symmetry axis. These aberrations are corrected by a set of coil pairs tilted with respect to the system axis, which generate compensating aberrations of the same type.

Abstract: A deflection magnetic system and method are provided to deflect an electron beam through a predetermined angle while maintaining a circular cross-section for the electron beam. A plurality of spaced magnetic fields are provided to deflect the electron beam through angles less than the total predetermined angle, but the total angle is achieved when the beam passes through the last magnetic field. Magnetic shields are provided between the spaced magnetic fields to absorb any undesired leakage magnetic flux.

Abstract: A controlled gradient device acts as a reflectron that controls the velocity and direction of a charged particle stream when an external voltage source is applied. An enclosing insulating structure has a metallized contact ring on each end. The interior surface has a resistive coating to provide a continuous electrically resistive surface that generates a desired voltage gradient along the length when a voltage is applied across the metallized contact rings. Each of the metallized contact rings can be a metal mesh that is coincident with a cross-sectional region of the conduit so that the electrical potential is constant at these locations.

Abstract: A charged particle beam is controlled by two pairs of deflectors that adjust the beam through two or more deflection centers, thereby saving cost and space and reducing system noise. The mathematics of the superposition of signals and, therefore, of the deflecting fields provide orthogonality of the adjustments so that all adjustments are independent of each other.

Abstract: A mass spectrometer with phonon sensitive cryogenic particle detector determines the masses of macromolecules, proteins, large peptides, long DNA-fragments and polymers. The kinetic energy of the electrostatically accelerated charged macromolecule is absorbed in the cryogenic particle detector thereby exciting phonons which are detected by phonon sensors. The macromolecules are detected in the single particle counting mode with a sensitivity independent of their respective masses. The mass spectrometer contains a single-channel cryogenic particle detector providing high sensitivity. The mass spectrometer contains a spatially resolving multi-channel cryogenic detector array providing both high sensitivity and high throughput. The mass spectrometer consists of a vacuum vessel in which is a magnet, a mass separator, a feed through and a phonon sensitive cryogenic detector array. The cryogenic detector array consists of an absorber and a specified number of phonon sensors.

Abstract: A focused ion beam column featuring a combination of blanker electrodes and a chicane system of electrodes which permit selection of a target spot size by selection of appropriate voltages applied to the chicane electrodes. The chicane potentials deflect the beam such as to select the closest distance between the center of the beam and the edge of a blocker plate thus reducing beam blurring when the beam is quickly turned off and on.

Abstract: Purely electrical or magnetic deflection systems are usually utilized in the probe-shaping part of modern electron beam tomographs in order to remove the gas ions generated in the evacuated drift tube by electron impact from the beam. The known deflection systems, however, cause an offset of the electron beam, so that this enters extra-axially into the lens element following the deflection system. In the apparatus for removing ions from an electron beam disclosed herein, a deflection unit (Wien filter) generates an E.times.B field oriented perpendicular to the beam axis that exerts strong shearing forces only on the positively charged gas ions, but does not influence the electrons. The deflection unit is essentially composed of two tube electrodes lying at a constant potential, of an electrostatic octopole deflector, and two saddle coil pairs annularly surrounding the octopole deflector. The apparatus is useful for fast electron beam tomographs, including x-ray scanners.

Abstract: Circuitry that controls a multiple-plate charged particle beam deflection arrangement includes a Digital Signal Processor (DSP) acting through a separate accumulating Arithmetic Logic Unit (ALU) connected to each of the plates. For each line to be scanned, at the commencement of the scanning of the line, the DSP delivers to each accumulating ALU a separate signal composed of a digital number representing an initial value (if any) and a digital number representing a step size. During each subsequent cycle of a clock, each accumulating ALU successively adds the step size to a resulting cumulative sum. This cumulative sum depends upon the initial value (if any) plus the step size multiplied by the number of cycles that have elapsed since the initial cycle.

Abstract: A method and apparatus for a charged particle scanning system and an automatic inspection system, including wafers and masks used in microcircuit fabrication. A charged particle beam is directed at the surface of a substrate for scanning that substrate and a selection of detectors are included to detect at least one of the secondary charged particles, back-scattered charged particles and transmitted charged particles from the substrate. The substrate is mounted on an x-y stage to provide at least one degree of freedom while the substrate is being scanned by the charged particle beam. The substrate is also subjected to an electric field on it's surface to accelerate the secondary charged particles. The system facilitates inspection at low beam energies on charge sensitive insulating substrates and has the capability to accurately measure the position of the substrate with respect to the charged particle beam.

Abstract: The invention relates to methods and devices for the reflection of positively and negatively charged particles of moderate kinetic energies at surfaces of any form. The invention consists in the production of a virtual or real surface for reflecting charged particles by creation of strongly inhomogenous high frequency fields of low penetration range into the space above the surface. The inhomogenous electric field is produced by supply of a high frequency voltage to a narrow grid pattern forming the surface and consisting of electrically conducting electrodes, isolated from each other. The electrode elements of the pattern are regularly repeated in at least one direction within the surface. The phases of the high frequency voltage are connected alternately to subsequent grid elements. The invention can be used to build new types of ion storage devices and ion guides for the transport of ions in moderate and high vacuum. New types of mass filters can be produced by this invention.

Abstract: To improve in the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector, a glitch waveform generated during a step change in the output or a D/A converter at the preceding stage of the amplifier, is anticipated and is canceled out with a correction waveform, after the output of the D/A converter has settled, this output is sample held and the step change is interpolated at a smoothing circuit, the deflection area is increased by positioning a electrostatic deflector offset around the optical axis relative to another electrostatic deflector, the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turn, and the alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area.

Abstract: An apparatus employs two spaced apart dipole magnets. An ion beam containing carbon of mass 2, 13 and 14 is focused by an Einzel lens and is directed into a first dipole magnet. The first magnet causes the beam to bend approximately 70 degrees, which separates the mass 12, 13 and 14 ions while at the same time focusing them in the X direction or deflection plane. The ions exit the first dipole magnet and pass through a blanking plate which can selectively remove one or two of the beams of mass 12, 13 and 14 ions. After leaving the first bending magnet, the mass 12 and 14 beams pass through a steering device so the trajectories of the mass 12 and 14 ions are deflected a few degrees to bring them parallel to the mass 13 ion beam. The parallel ion beams next pass through an electrostatic slot lens which focuses the beams in the direction out of the bending plane. After passing through the slot lens, the mass 12 and 14 beams are deflected in like amount to the deflection at the first steering device.

Abstract: A scanning system (25) for controlling a scanning servo (28,30) includes a scanning signal generator (50) which generates (51) a series of square wave scan signals, a pulse signal generator which generates (52) a pattern of pulses having short durations relative to the scan signal from the first generator, the generators being synchronized, and the scan signals and pulses then being separately applied to the scanner servo (30) to control it such that the resulting scanning behavior of the servo corresponds to the scan signals modified by the pattern of pulses.

Abstract: An auto focusing apparatus of a scanning electron microscope includes an auto focusing mechanism which calculates a focus evaluation value, using an electron signal or picture signal generated from a specimen when the specimen is scanned by an electron beam focused by an objective lens, and controls an exciting current of the objective lens according to said focus evaluation value. A focus correction value register and a focus correction mechanism for correcting the focused position determined by the aforementioned auto focusing mechanism by as much as the correction value registered in the focus correction value register are provided.

Abstract: An electron deflection device responsive to an electrical input signal for producing an output signal includes a focusing array for producing a collimated electron beam input ribbon in the direction of a propagation axis, the input ribbon being elongated along an array axis perpendicular to the propagation axis, and being relatively thin along a deflection axis perpendicular to the array axis and to the propagation axis. The focusing array is preferably a linear array of gated cold cathode units with lens electrodes. The deflection device further includes first and second electrically conductive deflector faces, forming a deflection region therebetween and being disposed so that the propagation-axis passes through the deflection region.

Abstract: An energy filter for charged particles includes a stack of micro-machined wafers including plural apertures passing through the stack of wafers, focusing electrodes bounding charged particle paths through the apertures, an entrance orifice to each of the plural apertures and an exit orifice from each of the plural apertures and apparatus for biasing the focusing electrodes with an electrostatic potential corresponding to an energy pass band of the filter.

Abstract: Deflection apparatus is shown for high perveance ion beams, operating at 20 Hz fundamental and substantially higher order harmonics, having a magnetic structure formed of laminations with thickness in range between 0.2 and 1 millimeter. Additionally, a compensator is shown with similar laminated structures with resonant excitation circuit, operating at 20 Hz or higher, in phase locked relationship with the frequency of the previously deflected beam. Furthermore, features are shown which have broader applicability to producing strong magnetic field in magnetic gap. Among the numerous important features shown are special laminated magnetic structures, including different sets of crosswise laminations in which the field in one lamination of one set is distributed into multiplicity of laminations of the other set of coil-form structures, field detection means and feedback control system, cooling plate attached in thermal contact with number of lamination layers.

Abstract: A synchrotron radiation light-source apparatus is provided in which the characteristics of synchrotron radiation generated by bending electromagnets can be made uniform, and emittance can be made smaller to increase brightness. The synchrotron radiation light-source apparatus for bending the traveling direction of an electron beam with bending electromagnets and for emitting synchrotron radiation includes deflecting electromagnets which cause a negative value (-dBy/dx) of a magnetic-field gradient gradually to increase after gradually decreasing in the traveling direction of the electron beam, that is, along the length of the bending electromagnets, so as to form a smooth recessing distribution, or to increase in a step-like manner after decreasing in a step-like manner.

Abstract: The invention is directed to a method for illuminating an object with a focused electron beam as well as to an electron-optical illuminating apparatus therefor. The crossover of an electron source is imaged, greatly demagnified, into the object plane via four imaging stages. The two first condenser stages define a zoom system. The cross section of the crossover image in the input image plane of the third condenser stage can be varied by varying the corresponding lens excitation. The third condenser stage images the crossover image from the input image plane into the input image plane of the objective. A multiple diaphragm is mounted between the third condenser stage and the input image plane of the objective. This multiple diaphragm has several apertures which are, in part, off-axis.

Abstract: A reflectron capable of focusing an entire mass range of product ions at substantially the same focal point, comprising a plurality of lens plates, each having an opening therein, for generating a non-linear electric field in the reflectron. To generate the non-linear electric field, the voltage applied to each successive lens plate increases non-linearly with respect to its adjacent lens plate. The voltage of the first lens plate having the opening through which the ions first enter the reflectron is set to a low potential and the voltage being applied to each successive lens plate increases in a non-linear manner with the largest voltage being applied to the lens plate furthest from the first lens plate. This non-linear voltage application, to generate the non-linear electric field, can be achieved by coupling a potentiometer between each lens plate and adjusting each potentiometer accordingly.

Abstract: An apparatus for exposing a radiation sensitive workpiece to define patterns therein includes an electron gun, a mask with spaced apertures for passing electron radiation, and a radiation deflector-blanker to direct the radiation to selected ones of the apertures and to form separate beamlets from the apertures then demagnify the separate beamlets and direct them onto the workpiece without crossing them. In one embodiment, the groups of apertures are fixed on the mask and define fixed undivided profiles in the path of the radiation.

Abstract: An electrostatic lens produces a smooth potential distribution along the center axis and is reduced in lens size and in total shape. A metal layer 13 is deposited at a certain position on an inner surface of insulating cylinder 11, and a high-resistance layer 12 is deposited on a portion except for the metal layer 13 on the inner surface of cylinder 11. A negative potential is applied from an external power source 19 to the metal layer 13, and the high-resistance layer 12 is earthed.

Abstract: A charged particle beam apparatus includes a charged particle beam generating system for causing a charged particle source to generate a charged particle beam. A focusing system focuses the charged particle beam onto a sample. A deflecting system causes the focused charged particle beam to scan the surface of the sample. An evacuating system evacuates a space through which the charged particle beam passes. A detector detects information obtained by irradiating the charged particle beam onto the sample. An image display system displays as an image the status of distribution of the information over the sample surface based on a detection signal forwarded from the detector. The focusing system is entirely constituted by an electrostatic lens containing a plurality of lens electrodes, one of the lens electrodes being a final electrode located closest to the sample.

Abstract: An electron linear accelerator for use in industrial material processing, comprises an elongated, resonant, electron accelerator structure defining a linear electron flow path and having an electron injection end and an electron exit end, an electron gun at the injection end for producing and delivering one or more streams of electrons to the electron injection end of the structure during pulses of predetermined length and of predetermined repetition rate, the structure being comprised of a plurality of axially coupled resonant microwave cavities operating in the .pi./2 mode and including a graded-.beta. capture section at the injection end of the structure for receiving and accelerating electrons in the one or more streams of electrons, .beta.

Abstract: A charged particle beam-exposure method in which a subject is exposed to a pattern via a charged particle beam having an on/off exposure characteristic. A blanking aperture array has n open/close devices which individually/correspond to respective scan positions of the charged particle beam and operate to control the on/off exposure characteristic of the charged particle beam.

Abstract: A mass spectometer for analyzing a beam of ions generated from a sample of analyze comprises an analyzer (3) and an interface between the analyze sample (1) and the analyzer. The inlet aperture to the analyzer (13) is positioned off the axis of the ion beam (2) exiting the interface system, and a deflector is (14) provided to generate an electric field between the interface system and the analyzer to deflect the ion beam into the inlet aperture of the analyzer.

Abstract: The invention relates to a scanning electron beam device in which at least one electrostatic reflector is provided for reflection of a secondary electron beam emitted by the primary electron beam on the object. This reflector is preferably located outside the beam path of the primary electron beam, and at least one electron-optical element which effects a preliminary deflection of the secondary electron beam by a small angle with respect to the beam path of the primary electron beam is provided between the object and the reflector. Such an arrangement makes it possible with comparatively low technical expenditure to reflect the secondary electron beam by a relatively large angle with respect to the unaffected primary electron beam which travels on a straight axis.

Abstract: A structure and method of accurately positioning and aligning an extraction member aperture (arc slit) and an extraction electrode gap with a predetermined beam line in an ion implantation apparatus is disclosed. The extraction member aperture is positioned with respect the ion beam source housing thereby eliminating cumulative tolerance errors which plague prior art ion implantation apparatuses. A removable alignment fixture is used in conjunction with a self-centering clamping assembly to accurately position the extraction member aperture in alignment with the predetermined beam line. The extraction member is secured to a support ring of the clamping assembly and the clamping assembly is mounted to the alignment fixture. The alignment fixture is mounted to the source housing precisely aligning the extraction member aperture with the predetermined beam line. The split ring of the clamping assembly is secured to a support tube surrounding the ion generating arc chamber.

Abstract: Spurious electrodynamic effects are reduced or eliminated by the use of a mechanically compact, low capacitance, geometrically symmetric, differentially-driven blanker assembly. This eliminates the need for internal cables or SMA-type launchers and has a solid metal electromechanical contact to system ground.