Abstract: A defect inspection method includes generating and applies a charged beam to a sample with patterns; controlling a shape of the charged beam so that a beam width in a first direction perpendicular to an optical axis differs from a beam width in a second direction perpendicular to the optical axis and the first direction, while substantially maintaining a cross-sectional area of the beam; scanning the sample with the charged beam having the controlled shape; and detecting charged particles from the sample by irradiation of the charged beam and detects a defect of the patterns. Assuming that the beam width of the charged beam in the first direction is smaller than that in the second direction, the first direction is set to a direction in which an interval between adjacent patterns becomes a minimum value and the sample is scanned in the second direction.

Abstract: The invention provides a method to real time monitor the ion beam. Initially, turn on an ion implanter which has a wafer holder, a Faraday cup and a measurement device positioned close to a special portion of a pre-determined ion beam path of the ion beam, wherein the Faraday cup is positioned downstream the wafer holder and the measurement device is positioned upstream the wafer holder. Then, measure a first ion beam current received by the Faraday cup and a second ion beam current received by the measurement device. By continuously measuring the first and second ion beam current, the ion beam is real-time monitored even the Faraday cup is at least partially blocked during the period of moving the wafer holder across the ion beam. Accordingly, the on-going implantation process and the operation of the implanter can be adjusted.

Abstract: There is proposed an apparatus for doping a material to be doped by generating plasma (ions) and accelerating it by a high voltage to form an ion current is proposed, which is particularly suitable for processing a substrate having a large area. The ion current is formed to have a linear sectional configuration, and doping is performed by moving a material to be doped in a direction substantially perpendicular to the longitudinal direction of a section of the ion current.

Abstract: Disclosed is an ion generating apparatus including a housing that is configured to be capable of specifically setting the positional relationship between the ion generating apparatus and an object from which adhering odors are to be removed. The ion generating apparatus is capable of directionally emitting ions toward the object.

Abstract: In a multi-charged-particle-beam apparatus, when an electric field and voltage on a surface of a specimen are varied according to characteristics of the specimen, a layout of plural primary beams on the surface of the specimen and a layout of plural secondary beams on each detector vary. Then, calibration is executed to adjust the primary beams on the surface of the specimen to an ideal layout corresponding to the variation of operating conditions including inspecting conditions such as an electric field on the surface and voltage applied to the specimen. The layout of the primary beams on the surface of the specimen is acquired as images displayed on a display of reference marks on the stage. Variance with an ideal state of the reference marks is measured based upon these images and is corrected by the adjustment of a primary electron optics system and others.

Abstract: A charged particle lithography system for pattern transfer onto a target surface, comprising a beam generator for generating a plurality of beamlets, and a plurality of aperture array elements comprising a first aperture array, a blanker array, a beam stop array, and a projection lens array. Each aperture array element comprises a plurality of apertures arranged in a plurality of groups, wherein the aperture groups of each aperture array element form beam areas distinct and separate from non-beam areas formed between the beam areas and containing no apertures for beamlet passage. The beam areas are aligned to form beam shafts, each comprising a plurality of beamlets, and the non-beam areas are aligned to form non-beam shafts not having beamlets present therein. The first aperture array element is provided with cooling channels in the non-beam areas for transmission of a cooling medium for cooling the array element.

Abstract: A combined laser and charged particle beam system. A pulsed laser enables milling of a sample at material removal rates several orders of magnitude larger than possible for a focused ion beam. In some embodiments, a scanning electron microscope enables high resolution imaging of the sample during laser processing. In some embodiments, a focused ion beam enables more precise milling of the sample. A method and structure for deactivating the imaging detectors during laser milling enables the removal of imaging artifacts arising from saturation of the detector due to a plasma plume generated by the laser beam. In some embodiments, two types of detectors are employed: type-1 detectors provide high gain imaging during scanning of the sample with an electron or ion beam, while type-2 detectors enable lower gain imaging and endpoint detection during laser milling.

Abstract: A thermal material-processing method wherein between the working spot of an electron beam and a workpiece a relative motion is brought about. Prior to the actual thermal treatment an effective processing contour is ascertained, in that the working spot of the electron beam executes, in accordance with the stored data of an ideal processing contour, a relative motion in relation to the workpiece, and on this relative motion a scan motion is superimposed which is directed transversely to the ideal processing contour. In this manner, both geometrical and magnetically conditioned deviations of the points of incidence of the electron beam on the workpiece can be compensated.

Abstract: When a predetermined region of a target volume is divided into multiple layers in a depth direction of particle beams and particle beams are irradiated, dose calibration is carried out separately for the divided layers.

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 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 a particle-beam projection processing apparatus for irradiating a target by a beam of energetic electrically charged particles, including an illumination system, a pattern definition system for positioning an aperture arrangement composed of apertures transparent to the energetic particles in the path of the illuminating beam, and a projection system to project the beam onto a target, there is provided at least one plate electrode device, which has openings corresponding to the apertures of the pattern definition system and including a composite electrode composed of a number of partial electrodes being arranged non-overlapping and adjoining to each other, the total lateral dimensions of the composite electrode covering the aperture arrangement of the pattern definition system. The partial electrodes can be applied different electrostatic potentials.

Abstract: Methods are disclosed that include exposing, in direct succession, portions of a surface of a sample to a charged particle beam, the portions of the surface of the sample forming a row in a first direction, the charged particle beam having an average spot size f at the surface of the sample, each portion being spaced from its neighboring portions by a distance of at least d in the first direction, and a ratio d/f being 2 or more.

Abstract: A processing system includes a piping which extends annularly, such as in the form of a circular annular shape, around a beam path between a focusing lens and an interaction region. The piping includes, on a side which faces the interaction region, a plurality of exit openings for the gas towards the interaction region. The piping also includes a holder configured to pivot the piping about a pivot axis. The holder is parallel to the tilt axis of the object holder.

Abstract: One embodiment relates to an electron-beam apparatus for defect inspection and/or review of substrates or for measuring critical dimensions of features on substrates. The apparatus includes an electron gun and an electron column. The electron gun includes an electron source configured to generate electrons for an electron beam and an adjustable beam-limiting aperture which is configured to select and use one aperture size from a range of aperture sizes. Another embodiment relates to providing an electron beam in an apparatus. Advantageously, the disclosed apparatus and methods reduce spot blur while maintaining a high beam current so as to obtain both high sensitivity and high throughput.

Abstract: An ion implantation system may comprise a plasma source for providing a plasma and a workpiece holder arranged to receive a bias with respect to the plasma to attract ions across a plasma sheath toward the substrate. The system may also include an extraction plate arrangement comprising a multiplicity of different apertures each arranged to provide an ion beam having ions distributed over a range of angles of incidence on the workpiece, wherein a first ion beam extracted from a first aperture has a first beam profile that differs from a second ion beam extracted from a second aperture.

Abstract: Disclosed is an operation for an optical system which achieves observation of focused ion beam processing equivalent to that in a case wherein a sample stage is tilted mechanically. In a focused ion beam optical system, an aperture, a tilting deflector, a beam scanner, and an objective lens are controlled so as to irradiate an ion beam tilted to the optical axis of the optical system, thereby achieving thin film processing and a cross section processing without accompanying adjustment and operation for a sample stage. The thin film processing and the cross section processing with a focused ion beam can be automated, and yield can be improved. For example, by applying the present invention to a cross section monitor to detect an end point, the cross section processing can be easily automated.

Abstract: The energy of positive ions accelerated in laser-matter interaction experiments can be significantly increased by providing a plurality of laser pulses, e.g., through the process of splitting the incoming laser pulse, to form multiple laser-matter interaction stages. From a thermodynamic point of view, the splitting procedure can be viewed as an effective way of increasing the efficiency of energy transfer from the laser light to positive ions, which energy peaks for processes having the least amount of entropy gain. A 100% increase in the energy efficiency is achieved for a six-stage laser positive ion accelerator compared to a single-stage laser positive ion accelerator.

Abstract: Provided is an ion beam device provided with a gas electric field ionization ion source which can prevent an emitter tip from vibrating in a non-contact manner. The gas electric field ionization ion source is comprised of an emitter tip (21) for generating ions; an emitter base mount (64) for supporting the emitter tip; an ionizing chamber which has an extraction electrode (24) opposed to the emitter tip and which is configured so as to surround the emitter tip (21); and a gas supply tube (25) for supplying gas to the vicinity of the emitter tip. The emitter base mount and a vacuum container magnetically interact with each other.

Abstract: The invention relates to a charged particle multi-beamlet lithography system for exposing a target using a plurality of beamlets. The system has a beam generator, a beamlet blanker, and a beamlet projector. The beam generator is configured to generate a plurality of charged particle beamlets. The beamlet blanker is configured to pattern the beamlets. The beamlet projector is configured to project the patterned beamlets onto the target surface. The system further has a deflection device. The deflection device has a plurality of memory cells. Each memory cell is provided with a storage element and is connected to a switching electrode of a deflector.

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: The system for irradiating patients with charged particles includes a raster scanning irradiation unit with a particle accelerator, a beam guide unit, and a 3D scanning system. It also contains a therapy planning system for generating therapy planning data, which include the energy and number of charged particles per raster point in each layer as derived from the derived dose distribution; a therapy control system, which converts the planning data generated by the therapy planning system into irradiation data and irradiation commands for the particle accelerator, the beam guide unit, and the 3D scanning system. The system further has a plurality of safety devices for ensuring that the therapy planning data have been converted correctly and for verifying the functionality of the system.

Abstract: A partial ovoidal FAIMS apparatus for separating ions is presented with inner and outer electrodes that have geometrically matched convex and concave partial ovoidal surfaces, respectively, that share at least one common defining axis and display a nearly constant displacement between the opposing surfaces. The ovoidal surfaces can be that of an egg shaped ovoid, an ellipse, or a sphere. The apparatus can have at least one ion inlet and an ion outlet where the outlet is on or as near as possible to a point on the defining axis in the outer electrode and the inlet or inlets are on, near, or symmetrically disposed about the defining axis of the ovoidal surfaces. Electrical contacts to the electrodes permit the application of an asymmetric waveform and a compensation voltage to at least one of the electrodes. The electrodes are positioned, stabilized, and insulated from each other by a base plate.

Abstract: A method and system for treating a non-planar structure is described. The method includes forming a non-planar structure on a substrate. Additionally, the method includes generating a gas cluster ion beam (GCIB) formed from a material source for treatment of the non-planar structure, tilting the substrate relative to the GCIB, and irradiating the non-planar structure with the GCIB. The system includes a substrate tilt actuator coupled to a substrate holder and configured to tilt the substrate holder relative to a GCIB.

Abstract: An inexpensive scanning irradiation device of a particle beam is obtained without using a rotating gantry. A first scanning electromagnet and a second scanning electromagnet, whose deflection surfaces of the particle beam are the same, and which bend the particle beam having an incident beam axis angle of approximately 45 degrees relative to a horizontal direction in reverse directions to each other; an electromagnet rotation driving mechanism which integrates the first and the second scanning electromagnets and rotates these scanning electromagnets around the incident beam axis; and a treatment bed are provided. The particle beam deflected by the first and the second scanning electromagnets can be obtained at a range of ?45 degrees to +45 degrees in deflection angle from an incident beam axis direction.

Abstract: In a maskless particle multibeam processing apparatus, a particle beam is projected through a pattern definition system producing a regular array of beamlets according to a desired pattern, which is projected onto a target which moves at continuous speed along a scanning direction with respect to the pattern definition system. During a sequence of uniformly timed exposure steps the beam image is moved along with the target along the scanning direction, and between exposure steps the location of the beam image is changed with respect to the target. During each exposure step the target covers a distance greater than the mutual distance of neighboring image elements on the target.

Abstract: An apparatus basically uses a simple and compact multi-axis magnetic lens to focus each of a plurality of charged particle beams on sample surface at the same time. In each sub-lens module of the multi-axis magnetic lens, two magnetic rings are respectively inserted into upper and lower holes with non-magnetic radial gap. Each gap size is small enough to keep a sufficient magnetic coupling and large enough to get a sufficient axial symmetry of magnetic scale potential distribution in the space near to its optical axis. This method eliminates the non-axisymmetric transverse field in each sub-lens and the round lens field difference among all sub-lenses at the same time; both exist inherently in a conventional multi-axis magnetic lens.

Abstract: There is provided a charged particle beam writing apparatus in which data processing is optimized by automatically dividing process regions on which parallel distributed processing is performed.

Abstract: A multi-beam source for generating a plurality of beamlets of energetic electrically charged particles. The multi-beam source includes an illumination system generating an illuminating beam of charged particles and a beam-forming system being arranged after the illumination system as seen in the direction of the beam, adapted to form a plurality of telecentric or homocentric beamlets out of the illuminating beam. The beam forming system includes a beam-splitter and an electrical zone device, the electrical zone having a composite electrode composed of a plurality of substantially planar partial electrodes, adapted to be applied different electrostatic potentials and thus influencing the beamlets.

Abstract: A particle therapy gantry for delivering a particle beam to a patient includes a beam tube having a curvature defining a particle beam path and a plurality of fixed field magnets sequentially arranged along the beam tube for guiding the particle beam along the particle path. In a method for delivering a particle beam to a patient through a gantry, a particle beam is guided by a plurality of fixed field magnets sequentially arranged along a beam tube of the gantry and the beam is alternately focused and defocused with alternately arranged focusing and defocusing fixed field magnets.

Abstract: A method for generating and visualizing an ion beam profile is provided. The method includes specifying an incidence direction of a particle beam, specifying a target region that is to be irradiated by said particle beam, creating an ion beam profile from points that are located on a downstream side of the target region or that are located in front of the target region and project onto the contour of the target region with respect to the incidence direction, and displaying a graphical representation of the ion beam profile.

Abstract: Initially, an ion beam is formed as an elongated shape incident on a wafer, where the shape has a length along a first axis longer than a diameter of the wafer, and a width along a second axis shorter than the diameter of the wafer. Then, a center of the wafer is moved along a scan path intersecting the ion beam at a movement velocity, and the wafer is rotated around at a rotation velocity simultaneously. During the simultaneous movement and rotation, the wafer is totally overlapped with the ion beam along the first axis when the wafer intersects with the ion beam, and the rotation velocity is at most a few times of the movement velocity. Both the movement velocity and the rotation velocity can be a constant or have a velocity profile relative to a position of the ion beam across the wafer.

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: The invention provides a magnetic lens for generating a magnetic imaging field to focus charged particles emitted from a sample, the lens comprising a central pole piece and an outer pole piece disposed about the central pole piece, wherein the lens comprises a magnetic moveable element for movement relative to at least one of the pole pieces, whereby a focal length of the lens is variable by said movement of the magnetic moveable element, thereby enabling a zoom facility for changing the magnification of an image. The movement of the moveable element preferably changes the magnetic circuit between the pole pieces. Also provided is a method of focusing charged particles emitted from a sample and a charged particle energy analyzer, such as an imaging photoelectron spectroscopy system.

Abstract: A collimator magnet (CM) usable in an ion implantation system provides an exit ion beam with a large aperture, substantially parallel in one plane or orthogonal planes. The CM includes identical poles, defined by an incident edge receiving an ion beam, and an exit edge outputting the ion beam for implantation. Ion beam deflection takes place due to magnetic forces inside the CM and magnetic field fringe effects outside the CM. The CM incident and/or exit edge is shaped by solving a differential equation to compensate for magnetic field fringe effects and optionally, space charge effects and ion beam initial non-parallelism. The CM shape is obtained by imposing that the incidence or exit angle is substantially constant, or, incidence and exit angles have opposite sign but equal absolute values for each ray in the beam; or the sum of incidence and exit angles is a constant or a non-constant function.

Abstract: A spin isolation apparatus comprising a particle source for emitting particles having spins, a receiving section for receiving the particles emitted by the particle source, a magnet for separating the particles into first particles having positive spins and second particles having negative spins, and a trajectory restricting section for isolating the first and the second particles received by the receiving section through restricting trajectories of the first particles and/or the second particles is provided. By applying this apparatus, particles having spins whose every sign is either one of the two signs can be mass-produced.

Abstract: An apparatus for merging a low energy electron flow into a high energy electron flow may include: a high energy electron path for accommodating the high energy electron flow; and a plurality of magnetic elements arranged to guide the low energy electron flow through a chicane presenting a path having a first end and a second end. The path intersects the high energy electron path at the second end. The path has a plurality of turns and path segments intermediate the first and second ends. Respective adjacent path segments intersect at each respective turn. The path establishes a respective bend radius and subtends a respective path angle between respective adjacent path segments at each respective turn. Each respective path angle is maximized within predetermined path angle limits. Each respective bend radius is minimized within predetermined bend radius limits.

Abstract: The invention is directed to an arrangement for the illumination of a substrate with a plurality of individually shaped, controllable particle beams, particularly for electron beam lithography in the semiconductor industry. It is the object of the invention to find a novel possibility for illuminating a substrate with a plurality of individually shaped, controllable particle beamlets which permits a high-resolution structuring of substrates with a high substrate throughput without limiting the flexibility of the applicable structure patterns or limiting the high substrate throughput due to a required flexibility.

Abstract: A deflector array includes a plurality of deflectors, which deflect charged particle beams, arrayed on a substrate. Each of the plurality of deflectors includes a single opening formed in the substrate, and each of the plurality of deflectors includes a pair of electrodes that oppose each other through the opening and are configured to deflect a single charged particle beam. The plurality of deflectors are arrayed such that a length of the pair of electrodes in a longitudinal direction thereof is not less than a distance between centers of two of the plurality of deflectors that are located nearest to each other. The plurality of deflectors is arrayed to form a checkerboard lattice, and two openings of the two of the plurality of deflectors overlap in the longitudinal direction.

Abstract: An electrostatic latent image measuring device includes a charged particle optical system which irradiates an electron beam and charges a photoconductor sample, an exposure optical system which forms an electrostatic latent image on a surface of the photoconductor sample, and a scanning unit which scans the surface of the photoconductor sample by the electron beam, a distribution of the electrostatic latent image on the surface of the sample being measured by a signal detected by the scanning.

Abstract: A charged particle beam column includes a charged particle beam source to generate a charged particle beam; an objective lens to focus the charged particle beam in an object plane; a first condenser lens disposed in a beam path of the charged particle beam between the charged particle beam source and the objective lens; a deflector disposed in the beam path between the first condenser lens and the objective lens and configured to change an angle of incidence of the charged particle beam in an object plane; and an aberration corrector disposed in the beam path between the deflector and the objective lens and configured to compensate aberrations introduced by the objective lens. The aberration corrector is also configured to not compensate aberrations introduced by the first condenser lens.

Abstract: For maskless irradiating a target with a beam of energetic electrically charged particles using a pattern definition means with a plurality of apertures and imaging the apertures in the pattern definition means onto a target which moves (v) relative to the pattern definition means laterally to the axis, the location of the image is moved along with the target, for a pixel exposure period within which a distance of relative movement of the target is covered which is at least a multiple of the width (w) of the aperture images as measured on the target, and after said pixel exposure period the location of the beam image is changed, which change of location generally compensates the overall movement of the location of the beam image.

Abstract: A scanning charged particle apparatus includes a layered charged particle beam column package; a sample holder; and a layered differential pumping aperture that assists in maintaining two different vacuums.

Abstract: Charged particles that are in transit through a deflection system when the beam is repositioned do not received the correct deflection force and are misdirected. By independently applying signals to the multiple stages of a deflection system, the number of misdirected particles during a pixel change is reduced.

Abstract: A spin isolation apparatus comprising a particle source for emitting particles having spins, a receiving section for receiving the particles emitted by the particle source, a magnet for separating the particles into first particles having positive spins and second particles having negative spins, and a trajectory restricting section for isolating the first and the second particles received by the receiving section through restricting trajectories of the first particles and/or the second particles is provided. By applying this apparatus, particles having spins whose every sign is either one of the two signs can be mass-produced.

Abstract: A charged particle gun alignment assembly for emitting a charged particle beam along an optical axis of a charged particle beam device is described. The charged particle gun alignment assembly is configured to compensate for misalignment of the charged particle beam and includes a charged particle source having an emitter with a virtual source defining a virtual source plane substantially perpendicular to the optical axis; a condenser lens for imaging the virtual source; a final beam limiting aperture adapted for shaping the charged particle beam; and a double stage deflection assembly positioned between the condenser lens and the final beam limiting aperture, wherein the working distance of the condenser lens is 15 mm or less.

Abstract: The invention comprises an ion beam focusing method and apparatus used as part of an ion beam injection system, which is used in conjunction with multi-axis charged particle or proton beam radiation therapy of cancerous tumors. The ion beam focusing system includes two or more electrodes where one electrode of each electrode pair partially obstructs the ion beam path with conductive paths, such as a conductive mesh. In a given electrode pair, electric field lines, running between the conductive mesh of a first electrode and a second electrode, provide inward forces focusing the negative ion beam. Multiple such electrode pairs provide multiple negative ion beam focusing regions.

Abstract: A charged particle multi-beamlet system for exposing a target using a plurality of beamlets. The system comprises a first plate having a plurality of holes formed in it, with a plurality of electrostatic projection lens systems formed at the location of each hole so that each electron beamlet passes through a corresponding projection lens system. The holes have sufficiently uniform placement and dimensions to enable focusing of the beamlets onto the surface of the target using a common control voltage. Preferably the electrostatic projection lens systems are controlled by a common electrical signal to focus the electron beamlets on the surface without correction of the focus or path of individual electron beamlets.

Abstract: The invention relates to a device (2) for generating an ion beam (4), comprising a support (6), an ion source (18), this ion source having a lower end (8) connected to the support (6) and an upper end (10) opposite the lower end (8), and extraction means (12) for extracting the ions emitted by the source, this extraction means (12) comprising a wall (14) having an opening (16), the opening (16) being arranged close to the upper end (10) of the ion source (18) so as to allow the extracted ions to pass through this opening. This device (2) further includes means (M1, M2) for the generation of a magnetic field (B) capable of generating a magnetic field in the opening (16) of the extraction means, the generated magnetic field (B) being capable of deflecting charged particles (20) attracted by the ion source so that these charged particles do not reach the ion source.

Abstract: A charged particle beam writing apparatus includes a stage on which a target object is placed; an emitting unit configured to emit a charged particle beam to the stage side; a blocking unit arranged between the emitting unit and the stage and configured to block the charged particle beam emitted; a deflector having electrodes through which a current flows by applying a voltage and configured to deflect the charged particle beam passing between the electrodes onto the blocking unit by applying a predetermined voltage across the electrodes; an optical axis adjusting unit configured to correct optical axis deviation of the charged particle beam generated by continuously repeating irradiation (beam-ON) of the charged particle beam on a target object and blocking (beam-OFF) of the beam by applying a two-step voltage to the deflector; and a control unit configured to control the optical axis adjusting unit such that an amount of the optical axis deviation is corrected.

Abstract: A semiconductor manufacturing includes: an ion source and a beam line for introducing an ion beam into a target film which is formed over a wafer with an insulating film interposed therebetween; a flood gun for supplying the target film with electrons for neutralizing charges contained in the ion beam; a rotating disk for subjecting the target film to mechanical scanning of the ion beam in two directions composed of r-? directions; a rear Faraday cage for measuring the current density produced by the ion beam; a disk-rotational-speed controller and a disk-scanning-speed controller for changing the scanning speed of the target film; and a beam current/current density measuring instrument for controlling, according to the current density, the scanning speed of the target film.