Magnetic Lens Patents (Class 250/396ML)
  • Patent number: 6153885
    Abstract: A semiconductor manufacturing tool for charged particle lithography systems such as an EBPS comprises a magnetic deflector with a hub comprising a cylinder mounted on flange. The hub has an opening for a particle beam. Grooves on the surface of the flange at the base of the cylinder and slots in the edge of the cylinder support several deflection coil vanes. Each of the vanes is formed of substrate comprising a thin plate which has a left surface and a right surface. Complementary electrical coils are wound as a planar spirals on the left surface and on the right surface of the vanes with a via connection through the plate interconnecting the coils. The series connected, spiral coils are patterned as mirror images so that the magnetic fields from the coils are additive. To accommodate vanes carrying large currents, the plate is quartz and complementary copper conductor spirals are bonded to the sides of the quartz plate.
    Type: Grant
    Filed: June 3, 1999
    Date of Patent: November 28, 2000
    Assignee: Nikon Corporation
    Inventor: Rodney Arthur Kendall
  • Patent number: 6150657
    Abstract: An energy filter has a plurality of deflection means and is constructed by using the plural deflection means so that an average track of an electron beam is symmetric and the normal line to a symmetric plane is inclined against an incident direction of the electron beam.
    Type: Grant
    Filed: August 25, 1998
    Date of Patent: November 21, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Koji Kimoto, Yoshifumi Taniguchi, Shunroku Taya, Shigeto Isakozawa, Takashi Aoyama, Masakazu Saito, Tomoko Sekiguchi
  • Patent number: 6140642
    Abstract: There is disclosed an imaging energy filter equipped with a distortion corrector. The energy filter is incorporated in an electron microscope and includes a spectrometer having magnets for producing magnetic fields. In this spectrometer, coils for exciting the magnets and potentiometers having variable resistors are connected in parallel. The variable resistors of the potentiometers are shifted to control the ratio of currents flowing into coils of shunting circuits.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: October 31, 2000
    Assignees: Jeol Ltd., Michiyoshi Tanaka
    Inventors: Toshikatsu Kaneyama, Toshikazu Honda, Michiyoshi Tanaka, Masami Terauchi, Kenji Tsuda
  • Patent number: 6140645
    Abstract: There is disclosed a small-sized and inexpensive electron spectroscopic imaging (ESI) system using an .OMEGA.-filter. The amounts of currents supplied to the lenses located before and after the .OMEGA.-filter need not be varied, whether the .OMEGA.-filter is used or not. The .OMEGA.-filter has an entrance window and an exit window. A straight path is formed between these two windows. A coil in an objective lens is located above a specimen. An entrance aperture is positioned close to the back focal plane of the objective lens. The objective lens is so energized that an electron microscope image is focused at the center of the filter on the straight path. The first stage of imaging lens is so energized that an image at the position P is an object plane. This image is magnified and focused onto a fluorescent screen by the following stages of imaging lenses.
    Type: Grant
    Filed: October 16, 1998
    Date of Patent: October 31, 2000
    Assignee: Jeol Ltd.
    Inventor: Katsushige Tsuno
  • Patent number: 6130432
    Abstract: A magnetic lens having a lens bore for the passage of a particle beam includes a dynamic focus coil that is positioned outside the lens bore and within the pole piece that shapes the lens field, so that the magnetic flux lines from the dynamic focus coil all end on the pole pieces of the lens and the shape of the lens field between the pole pieces has its magnitude changed by the current passing through the dynamic focus coil, but the field shape is not changed, thus changing the focal plane of the beam without moving the beam transversely with respect to the system axis.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: October 10, 2000
    Assignee: International Business Machines Corporation
    Inventors: Hans C. Pfeiffer, Joseph J. Senesi, Maris Andris Sturans
  • Patent number: 6124596
    Abstract: The present invention provides CPB projection apparatus and transfer methods for transferring a pattern from a mask onto a wafer with precise linear-distortion correction of transferred images without creating significant astigmatic blur of the image. A preferred embodiment of the projection apparatus includes an illumination-optical system and a projection-optical system. The illumination-optical system includes a CPB source for emitting a charged-particle beam, and first and second condenser lenses. A field-limiting aperture limits the field of the charged-particle flux. A first astigmatic-aberration correction coil is positioned at a principal plane of either the first or second projection lens and corrects linear distortion of a resulting projected image. A third condenser lens collimates the beam to form an image of the field-limiting aperture on a selected subfield of the mask. A projection-lens system demagnifies the image formed by the mask and projects the demagnified image on a wafer.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: September 26, 2000
    Assignee: Nikon Corporation
    Inventors: Mamoru Nakasuji, Shohei Suzuki
  • Patent number: 6107633
    Abstract: An electron beam lens has a magnetic lens provided with first and second pole pieces for influencing an electron beam and forming a magnetic field between the two pole pieces. A third pole piece is provided, but is not in magnetic contact with the two other pole pieces. The third pole piece is immersed in the magnetic field formed between the first and second pole pieces and extracts a part of such magnetic field. Also disclosed is a cathode lens and an electron beam device for use with such an electron beam lens.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: August 22, 2000
    Assignee: Advantest Corporation
    Inventors: Jurgen Frosien, Stefan Lanio, Gerald Schonecker
  • Patent number: 6104034
    Abstract: The invention relates to an objective lens for influencing a particle beam, particularly an electron beam with a magnetic single-pole lens and an electrostatic lens having a first and a second electrode which can be supplied with different potentials. The objective lens is characterized in that the electrostatic lens is disposed after the magnetic single-pole lens in the direction of the particle beam.
    Type: Grant
    Filed: July 9, 1998
    Date of Patent: August 15, 2000
    Assignee: Advantest Corporation
    Inventors: Jurgen Frosien, Stefan Lanio, Gerald Schonecker
  • Patent number: 6097028
    Abstract: There is disclosed a highly isochromatic electron spectroscopic imaging filter providing good energy resolution even in a microscope image having a wide field of view. To reduce the difference in energy between the vicinity of the center of the image on the pupil plane and peripheral portions, the relation LL/L.sub.5 > is satisfied, where LL is the distance from the pupil plane to the slit plane S and L.sub.5 is the distance from the exit end surface of the filter to the slit plane S.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: August 1, 2000
    Assignee: JEOL Ltd.
    Inventor: Katsushige Tsuno
  • Patent number: 6087670
    Abstract: A synchrotron type accelerator including a deflecting electromagnet arranged on a circulating orbit of a charged particle beam, four-pole divergence electromagnets and four-pole convergence electromagnets arranged on said circulating orbit. A high frequency applying unit arranged on the circulating orbit for applying a high frequency electromagnetic field to the charged particle beam circulating and for increasing an amplitude of betatron oscillation of the particle beam to a level above a stability limit of resonance. A first deflector for beam ejection arranged on the circulating orbit for deflecting the charged particle beam excited above the stability limit of the resonance by the high frequency applying unit and a second deflector for beam ejection arranged on the circulating orbit used in pairs with the first deflector for beam ejection for introducing the charged particle beam deflected by the first deflector for beam ejection into an ejected beam transporting system.
    Type: Grant
    Filed: August 3, 1999
    Date of Patent: July 11, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Kazuo Hiramoto, Masumi Umezawa, Koji Matsuda
  • Patent number: 6078382
    Abstract: Charged-particle-beam projection optical systems are disclosed including a symmetric magnetic doublet comprising first and second magnetic lenses arranged along a system axis between a reticle position and a sample position. The lenses have point symmetry about a crossover point and a centrally located mutual focal point located between the two lenses. The dimensions on the sample-side of the cross-over point are reduced, in both the axial direction measured from the axis and the radial direction measured from the crossover point, by a demagnification ratio. The magnetic fields of each lens are opposite, the electrical excitation current applied to each lens coil is equal, and the lenses are preferably energized by the same power supply. A first beam deflector is located near the reticle inside the first lens; a second and third beam deflector are located inside the first lens and the second lens, respectively; and a fourth beam deflector is located near the sample inside the second lens.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: June 20, 2000
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 6069363
    Abstract: Resolution of a symmetric magnetic doublet charged particle beam projection lens is improved by applying a non-uniform electrostatic field having the same symmetry conditions as the lens through the magnetic doublet which provides a maximum particle velocity at the plane of symmetry of the magnetic doublet. Since the same symmetry conditions are used for both the electrostatic and magnetic fields, the performance of the magnetic doublet is not compromised. Electrode configurations which provide more intense fields provide further reduction in aberrations for a given potential superimposed on the accelerating voltage.
    Type: Grant
    Filed: February 26, 1998
    Date of Patent: May 30, 2000
    Assignee: International Business Machines Corporation
    Inventor: Steven D. Golladay
  • Patent number: 6066852
    Abstract: An electron energy filter includes a first pair of magnetic poles for generating a first deflecting magnetic field and a second pair of magnetic poles for generating a second deflecting magnetic field in the same direction as the first deflecting magnetic field. The incident electrons are deflected about 90.degree. with a trace radius of AM1 through the effect of the first deflecting magnetic field, passed through a free space having a distance DL2 that is about a half of the trace radius AM1 and then are incident to the second deflecting magnetic field. The electrons are deflected about 180.degree. with a trace radius AM2 that is about a half of the curvature radius AM1 and are passed through the free space DL2. Then, the electrons are incident to the first deflecting magnetic field again where those electrons are deflected about 90.degree.. The deflected electrons are traveled like a gamma trace so that those electrons outgo in the same direction as the incident one.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: May 23, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Shunroku Taya, Yoshifumi Taniguchi
  • Patent number: 6066853
    Abstract: Electron-optical systems are disclosed in having operating parameters that are quantitatively optimized in a short period of time. The systems comprise multiple deflectors that diminish off-axis aberrations. The deflectors are situated in a two-stage projection lens. The dimensions of the main field which in subfields are selected by electron-beam deflection are set to 10 mm or less. The dimensions of each transfer subfield on the surface of the substrate are set to (500 .mu.m).sup.2 to (750 .mu.m).sup.2, and the mask-to-specimen distance is set to 600 mm or less.
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: May 23, 2000
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 6064071
    Abstract: Charged-particle optical systems are disclosed for transferring high-resolution patterns from a mask to a wafer. One embodiment comprises a symmetric magnetic doublet lens and a plurality of deflectors. The deflectors satisfy variable axis lens (VAL) conditions and establish an effective optical axis. The deflectors also deflect the charged-particle beam so that a principal ray coincides with the effective optical axis. Symmetry conditions are provided for the symmetric magnetic doublet and the deflectors. In another embodiment, deflectors use a common series current.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: May 16, 2000
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 6060711
    Abstract: Charged-particle beam pattern transfer apparatus and charged-particle beam optical systems are disclosed. A representative charged-particle beam pattern transfer apparatus comprises a projection lens that images patterns from a mask onto a substrate. To reduce off-axis image aberrations, especially anisotropic coma and astigmatism, deflectors are provided that produce a magnetic field such that the effective optical axis of the lenses is along a straight line that is tilted with respect to the mask and the substrate. Focus correctors are provided that produce a magnetic field that corrects image focus. Mathematical descriptions of these magnetic fields are disclosed. With such magnetic fields, the charged-particle beam that irradiates a central region of a subfield on the mask propagates along a straight-line axis through the projection lens, reducing deflection aberration and improving image quality.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: May 9, 2000
    Assignee: Nikon Corporation
    Inventor: Hiroyasu Shimizu
  • Patent number: 6055719
    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.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: May 2, 2000
    Assignee: Fujitsu Limited
    Inventors: Yoshihisa Ooaeh, Tomohiko Abe, Hiroshi Yasuda
  • Patent number: 6053241
    Abstract: A method of cooling a deflection system for a particle beam, containing vibration sensitive deflection devices comprises providing a vibrating cooled heat exchange structure spaced away from the vibration sensitive deflection devices. The technique used is transmission of the heat away from the vibration sensitive devices to the heat exchange structure through a high thermal conductivity structure such as a cold plate. The heat is transmitted from a static heat exchange structure with a static, inert fluid through cold plates to a vibrating heat exchanger cooled by turbulent liquid passing through a cooling coil in the heat exchanger.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: April 25, 2000
    Assignee: Nikon Corporation
    Inventor: Rodney Arthur Kendall
  • Patent number: 6051839
    Abstract: Disclosed are lens apparatus in which a beam of charged particlesis brought to a focus by means of a magnetic field, the lens being situated behind the target position. In illustrative embodiments, a lens apparatus is employed in a scanning electron microscopeas the sole lens for high-resolution focusing of an electron beam, and in particular, an electron beam having an accelerating voltage of from about 10 to about 30,000 V. In one embodiment, the lens apparatus comprises an electrically-conducting coil arranged around the axis of the beam and a magnetic pole piece extending along the axis of the beam at least within the space surrounded by the coil. In other embodiments, the lens apparatus comprises a magnetic dipole or virtual magnetic monopole fabricated from a variety of materials, including permanent magnets, superconducting coils, and magnetizable spheres and needles contained within an energy-conducting coil.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: April 18, 2000
    Assignee: Arch Development Corporation
    Inventor: Albert V. Crewe
  • Patent number: 6049084
    Abstract: Charged-particle-beam optical systems are disclosed exhibiting reduced aberrations. Such a system comprises a symmetric magnetic doublet type projection lens system and deflectors. An imaginary Z-axis is superimposed on the optical axis with an origin at an image-crossover point. Excitation of the deflectors and lenses is controlled by a controller so that the ratio of G.sub.1 (Z) to G.sub.2 (-M.multidot.Z) is substantially equal to the ratio of (-M) to 1 (i.e., G.sub.1 (Z):G.sub.2 (-M.multidot.Z)=(-M):1), and the deflection trajectory of the charged-particle beam intersects with the optical axis at a crossover Z.sub.c, where M is the magnification of the lens system, G.sub.1 (Z) is the distribution of the deflective magnetic field formed on the object side of the crossover, and G.sub.2 (Z) is the distribution of the deflective magnetic field formed on the image side of the crossover.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: April 11, 2000
    Assignee: Nikon Corporation
    Inventor: Hiroyasu Simizu
  • Patent number: 6043488
    Abstract: A system for separating certain ions from an ion beam in a mass spectrometer. A magnetic or electrostatic field is applied at an angle to the ion beam, causing the ions to disperse according to their mass to charge ratio. The ions are dispersed enough to allow certain ions to be blocked and removed from the beam using a physical stop. A subsequent plurality of fields is then applied to reform the beam and adjust its direction and dispersion.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: March 28, 2000
    Assignee: The Perkin-Elmer Corporation
    Inventors: Dar Bahatt, David G. Welkie
  • Patent number: 6031239
    Abstract: The plasma beam from a cathodic arc is filtered by baffles, a double bend toroidal plasma duct and a biased, corrugated liner within the duct, giving coatings virtually free of contaminating macroparticles. Reactive gas is ionised in the plasma ball and automatic arc ignition is provided.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: February 29, 2000
    Assignee: Filpas Vacuum Technology Pte Ltd.
    Inventors: Xu Shi, David Ian Flynn, Beng Kang Tay, Hong Siang Tan
  • Patent number: 6028317
    Abstract: An optical element includes two electrodes 1 and 2 arranged at a distance to oppose each other and configured to converge an electron beam. The opposing surfaces of the electrodes 1 and 2 are so formed as to be cylindrically symmetrical along the beam passing direction and to form curves obtained by deforming hyperbolas in a direction perpendicular to the beam passing direction, in order that an electric field whose effective part except for an arbitrary constant of the field potential is given by.phi.=(k/2)r.sup.2 -.alpha.lnr-kz.sup.2is spatially partially formed in a cylindrical coordinate system defined by (r, z, .theta.).
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: February 22, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ken-ichi Murooka, Munehiro Ogasawara, Hitoshi Sunaoshi
  • Patent number: 6025600
    Abstract: A method for calculating and correcting an astigmatism error in a charged particle beam system. Images are collected during a single focus sweep of the charged particle beam system. Different orientations of image features, such as lines on a stigmation target, are analyzed. Optimum sharpness or best focus values are obtained as a function of the objective lens settings. Appropriate changes to the settings of the astigmatism correctors are computed by taking a linear combination of optimum sharpness values associated with the different orientations of image features. Proper settings of the objective lens and the astigmatism correctors result in focusing of the beam into a "small" spot. In a scanning electron microscope, for example, two sets of quadrupole compensation coils are typically used as astigmatism correctors.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: February 15, 2000
    Assignees: International Business Machines Corporation, Applied Materials, Inc.
    Inventors: Charles N. Archie, Steven R. Rogers, Eric P. Solecky
  • Patent number: 6015973
    Abstract: There is disclosed an energy filter having polepieces which form lenses and are mounted at accuracies that can be easily checked. The positions of the lenses can be easily readjusted. The lenses are mounted to a base plate and stacked on top of each other between two polepieces via two spacers. The polepieces form magnetic poles. These lenses are mounted to the base plate with screws so as to form a passage.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: January 18, 2000
    Assignee: JEOL Ltd.
    Inventor: Hiromi Nunome
  • Patent number: 6011268
    Abstract: Electron-beam demagnifying projection-optical systems are disclosed that perform magnification adjustment, image-rotation adjustment, and focus correction while not contributing to aberrations. Also disclosed are electron-beam microlithography apparatus comprising such a projection-optical system. The projection-optical system comprises first and second projection lenses arranged on an optical axis, and project an electron beam, that has passed through a mask pattern, with demagnification on a substrate. Each projection lens includes an auxiliary lens that generates a magnetic field having an axial strength distribution proportional to the axial magnetic field distribution of the respective projection lens. By adjusting the direction and amount of electrical current through the auxiliary lenses at least of focal point, image rotation, and image magnification can be independently adjusted.
    Type: Grant
    Filed: July 21, 1998
    Date of Patent: January 4, 2000
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 6008498
    Abstract: The imaging characteristics of focal-point position, image rotation, and magnification of a projection system of a charged-particle-beam image-transfer apparatus are corrected by correction lenses positioned between a first projection lens and a second projection lens. The driving currents of the correction lenses are determined by solving a system of three linear equations with three unknowns, whose coefficients are the correction amounts for the three imaging characteristics of the projection system produced by the three correction lenses when they are driven by the unit Ampere-turn, and the target correction amounts for the three imaging characteristics. More correction lenses can be employed than imaging characteristics to be corrected, with Ampere-turn values selected from among those that satisfy the corresponding equations. Also, the driving currents of one or more projection lenses can be varied to allow the projection lenses to operate as correction lenses.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: December 28, 1999
    Assignee: Nikon Corporation
    Inventor: Hiroyasu Simizu
  • Patent number: 6005250
    Abstract: An electron beam projection system comprises a source of an electron beam, a first doublet of condenser lenses with a first symmetry plane, a first aperture comprising a trim aperture located at the first symmetry plane of the first doublet also serving as a first blanking aperture. A second aperture comprises a shaping aperture located below the trim aperture. A second doublet of condenser lenses with a second symmetry plane is located below the second aperture, the second doublet having a symmetry plane. A third aperture is located at the symmetry plane of the second doublet wherein the third aperture comprises another blanking aperture. There are first blanking plates between the first condenser lens and the trim aperture, and second electrostatic alignment plates between the trim aperture and the second aperture.
    Type: Grant
    Filed: August 22, 1998
    Date of Patent: December 21, 1999
    Assignee: Nikon Corporation
    Inventors: Werner Stickel, Steven Douglas Golladay
  • Patent number: 6002135
    Abstract: A composite magnetic lens and deflector for particle beam optical systems has a concentric gap and concentric conical lower pole pieces arranged to allow more accurate magnetic deflection. The flux generated by a solenoidal lens coil is shared by magnetically soft inner and higher saturation flux outer pole pieces to minimize saturation effects, while the flux generated by internal deflection coils is confined to magnetically soft inner pole pieces that minimize flux leakage and associated eddy current settling effects. Shielding rings further contain leakage flux. The inner magnetic circuit is mounted and adhesively bonded to radial flexures to minimize thermal expansion drifts.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: December 14, 1999
    Assignee: Etec Systems, Inc.
    Inventors: Lee H. Veneklasen, William J. DeVore
  • Patent number: 5994704
    Abstract: Electromagnetic deflectors and methods for their manufacture are disclosed. The excitation coils inside such deflectors can be situated relative to each other and to an optical axis with a high degree of accuracy and precision. A pair of loop-shaped channels are formed opposite each other in the sides of a cylindrical insulating cylinder. An electrically conductive material is embedded in the channels to form a set of opposing coils operable to deflect a charged particle beam passing axially through the cylinder in one dimension. Multiple cylinders each comprising a set of opposing coils can be concentrically assembled to provide, e.g., a biaxial deflector operable to deflect the beam in an X-dimension and a Y-dimension. In such a biaxial deflector, the sets of coils are arranged perpendicular to each other. The cylinder(s) is placed concentrically inside a cylindrical outer casing made of a ferromagnetic material such as ferrite to make an electromagnetic deflector.
    Type: Grant
    Filed: October 3, 1997
    Date of Patent: November 30, 1999
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 5994703
    Abstract: A printed circuit for forming deflection coils used, for example, in a scanning electron microscope. The printed circuit permits some of scroll coil circuits to be connected with an external circuit with or without connecting them in series. There is also disclosed a printed circuit capable of forming deflection coils which are small in size but produce strong magnetic fields. A printed circuit according to the invention comprises a sheet on which the scroll coils and indicia are printed. When the sheet is wound into a cylinder, the scroll coils are arranged circumferentially.
    Type: Grant
    Filed: March 6, 1997
    Date of Patent: November 30, 1999
    Assignee: JEOL Ltd.
    Inventor: Yoshihiro Arai
  • Patent number: 5974112
    Abstract: A photon beam dose enhancement is controlled by configuring a topical magnetic field, the magnetic field configuration having a magnetic field component across the beam path and having a magnetic field gradient component along the beam path which cause the dose enhancement, the dose enhancement being changeable during beam use by changing the magnetic field configuration during beam use, wherein the topical magnetic field can be produced by an array of magnet coils.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: October 26, 1999
    Inventor: Leonard Reiffel
  • Patent number: 5969354
    Abstract: A charged-particle analyzer in which a solenoid or other means set up a generally axial magnetic field in a drift region. Meshes of magnetically permeable material are set at ends of the drift region to terminate the magnetic field. Charged particles, such as electrons, are incident upon entrance mesh at a given angle with respect to the central axis. After passing through the entrance mesh, they gyrate around the magnetic field lines, and they then exit the drift region through the exit mesh. The rotation accumulated across the drift region depends upon the energy of the incident particle, and the angle of the particle trajectory exterior of the exit mesh thus depends on the particle's energy. A charged-particle detector detects the position of the particle relative to the central axis and, hence, its energy. In one embodiment, the meshes are flat so that a uniform magnetic field is created in the drift region.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: October 19, 1999
    Inventor: Michael A. Kelly
  • Patent number: 5959303
    Abstract: A mass-analysed ion beam generator in which the ion beam is in the form of a thin flat ribbon with its major transverse dimension aligned parallel with the direction of the mass-analysing magnetic field.
    Type: Grant
    Filed: February 1, 1999
    Date of Patent: September 28, 1999
    Inventor: James Harry Freeman
  • Patent number: 5955732
    Abstract: There is disclosed a small-sized omega-type energy filter having reduced drift lengths and an increased merit function. Four magnetic fields M.sub.1, M.sub.2, M.sub.3, and M.sub.4 deflect the electron beam into an .OMEGA.-shaped orbit from the entrance window plane to the slit plane. The distance L.sub.4 from the exit end surface of the third field M.sub.3 to the entrance end surface of the fourth field M.sub.4 is set no greater than 50 .sqroot.U*/.sqroot.U*(200) mm. The deflection angle .PHI. is set to a range of from 120.degree.-50.degree. to 120.degree.+5.degree.. The distance L.sub.3 from the central plane between the second field M.sub.2 and the third field M.sub.3 to the entrance end surface of the third field M.sub.3 is set such that 20 .sqroot.U*/.sqroot.U*(200) mm .gtoreq.10.sqroot.U*/.sqroot.U*(200) mm. The distance L.sub.5 from the exit end surface of the fourth field M.sub.4 to the slit plane is set such that 30 .sqroot.U*/.sqroot.U*(200) mm.ltoreq.L.sub.5 .ltoreq.50 .sqroot.U*/.sqroot.U*(200) mm.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: September 21, 1999
    Assignee: Jeol Ltd.
    Inventor: Katsushige Tsuno
  • Patent number: 5952656
    Abstract: There is disclosed an .OMEGA.-filter for use with an electron microscope. This filter has only one parameter that controls the exciting currents supplied to four magnets M.sub.1 -M.sub.4. Only those electrons of incident electrons that have a given energy pass through the successive magnets and emerge from the filter. The coils of the magnets M.sub.1 and M.sub.4 are identical in number of turns and connected in series. Similarly, the coils of the magnets M.sub.2 and M.sub.3 are identical in number of turns and connected in series. When a human operator specifies an exciting current i.sub.1 through an entry device, a controller causes a power supply P.sub.1 to produce this exciting current i.sub.1, thus exciting the magnets M.sub.1 and M.sub.4. The controller calculates an exciting current i.sub.2 from the exciting current i.sub.1, and causes a power supply P.sub.2 to produce this exciting current i.sub.2, thus exciting the magnets M.sub.2 and M.sub.3.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: September 14, 1999
    Assignee: JEOL Ltd.
    Inventor: Toshikatsu Kaneyama
  • Patent number: 5952667
    Abstract: Charged-particle-beam microlithography apparatus are disclosed comprising a lens system, such as a variable axis lens (VAL) or variable axis immersion lens (VAIL), that causes a charged-particle-beam incident to an objective lens off-axis to be incident under the same conditions as if the beam were incident on-axis. The objective lens comprises astigmatism-correction deflectors that generate an astigmatism-correction field serving to correct astigmatism of the beam and generate a deflecting magnetic field that corrects the off-axis state in the astigmatism correction field relative to the charged-particle-beam. Thus, generation of aberrations is kept to a minimum even when the charged-particle-beam is incident off-axis.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: September 14, 1999
    Assignee: Nikon Corporation
    Inventor: Hiroyasu Shimizu
  • Patent number: 5939026
    Abstract: An electron beam gas processing apparatus includes a single vacuum vessel maintained at vacuum by means of a vacuum pump and first and second lenses are disposed in the vacuum vessel. An electron beam emitted from an electron source is focused by each of the lenses, and the electron beam is irradiated onto a processing gas in a duct. When the current value of the electron beam is increased as the concentration of NOx in the processing gas increases, the focal distance is decreased by increasing the intensity of magnetic fields or the intensity of electric fields of the lenses in accordance with the current value of a filament, the current value of an arc power supply and the gas pressure in a gas reservoir and the first lens is moved toward a draw-out electrode and the second lens is moved toward the duct, so that a parallel electron beam of constant diameter is formed and the electron beam can be prevented from being increased in focusing diameter.
    Type: Grant
    Filed: December 29, 1997
    Date of Patent: August 17, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Hirofumi Seki, Hirofumi Shirakata, Yasuro Hori, Shigeo Shiono
  • Patent number: 5929451
    Abstract: Symmetric magnetic doublets are disclosed that image a reticle onto a sensitized substrate using a charged-particle beam. The symmetric magnetic doublet comprises an object-side lens and an image-side lens and satisfies certain quantitative conditions. If the object-side lens has a length S.sub.1 and pole-piece apertures of radii R.sub.1, R.sub.2, and the image-side lens has a length S.sub.2 and pole-piece apertures of radii R.sub.3, R.sub.4, then a lens according to an embodiment of the invention produces a demagnification of 1/m in an object-image distance L between the reticle and the substrate. This embodiment satisfies the relations R.sub.3 =R.sub.2 /m, R.sub.4 =R.sub.1 /m, S.sub.2 =S.sub.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: July 27, 1999
    Assignee: Nikon Corporation
    Inventors: Shin-Ichi Kojima, Kazuya Okamoto
  • Patent number: 5895919
    Abstract: The invention relates to a gun lens for generating a particle beam with a cathode, an extraction electrode, an anode and a condenser lens, wherein a deceleration field is generated between the extraction electrode and the anode and the condenser lens produces a magnetic field which is superimposed on both the cathode, the extraction electrode and the anode.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: April 20, 1999
    Assignee: Advantest Corporation
    Inventors: Jurgen Frosien, Stefan Lanio, Gerald Schonecker
  • Patent number: 5850083
    Abstract: A charged particle beam lithograph apparatus of the present invention projects a charged particle beam onto a sample through a mask and lithographs a mask pattern on the sample through the movement of the charged particle beam. In order to focus the charged particle beam, the apparatus creates an electromagnetic field, from the magnetic lens, symmetric with respect to an optical axis of the charged particle beam. An aberration of the charged particle beam is created under the symmetric electromagnetic magnet. The aberration is compensated for under an electromagnetic field nonsymmetric with respect to the optical axis which is created by a deflection unit.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: December 15, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Souji Koikari, Shuichi Tamamushi, Shusuke Yoshitake, Munehiro Ogasawara
  • Patent number: 5847401
    Abstract: An apparatus for delivering a beam of charged particles along two separate beam paths comprising a pulsed charged particle beam source for producing a series of beam pulses along a first beam path, a switching magnet for developing a magnetic field, and a power supply means for selectively applying current pulses to said switching magnet in timed relation to each of a plurality of predetermined beam pulses effective to develop a constant magnetic field throughout the period of each predetermined beam pulse and deflect each entire predetermined beam pulse from said first beam path to a second beam path.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: December 8, 1998
    Assignee: Atomic Energy of Canada Limited
    Inventors: Joseph McKeown, Marshall R. Cleland, Norbert H. Drewell, Courtlandt B. Lawrence, Walter Garfield Davies
  • Patent number: 5847399
    Abstract: A deflection system (6) for a charged particle beam (2), in particular for rrangement in an objective lens for a charged particle beam device with a deflection means (60) for generating a magnetic field acting on the charged particle beam (2) and a shield (61) for avoiding eddy currents, which surrounds the deflection means and guides the formed outer magnetic field. The shield (61) consists, transversely to the direction of the charged particle beam (2), of at least one soft magnetic layer which is preferably formed as a strip material and rolled up to a cylinder together with an electrically insulating layer.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: December 8, 1998
    Assignee: ACT Advanced Circuit Testing Gesellschaft fur Testsystementwicklung mbH
    Inventors: Reinhold Schmitt, Stefan Lanio, Thomas Jasinski
  • Patent number: 5847402
    Abstract: This invention concerns a charged particle beam pattern transfer system which uses a flux of charged particles, e.g. from an electron or ion beam, to transfer a mask pattern to a sensitized substrate. In particular, the invention is applicable to an electron beam reduction transfer system which demagnifies and transfers a mask pattern defined by multiple mask subfields to a sensitized substrate using the step-and-repeat transfer method. The invention provides a system for transferring the mask subfields, separated from one another on the mask by boundary strips, onto a wafer such that the transferred images of the mask subfields are joined together on the wafer as transfer subfields lacking any intervening boundary regions.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: December 8, 1998
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 5831270
    Abstract: Magnetic deflectors for charged particle beams are provided. The magnetic deflectors comprise at least one pair of coils to provide high deflection sensitivity over large regions of uniform deflection without increasing the size of the magnetic core used by the deflectors. Charged-particle-beam lithography systems using such deflectors are also disclosed.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: November 3, 1998
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 5831274
    Abstract: A image transferring apparatus using a charged particle beam including a projection lens for transferring a pattern formed on a mask onto a target by focusing a charged particle beam passing through the mask, and a deflector for deflecting the charged particle beam passing through the mask toward a predetermined direction (x-axis direction) so that a transfer position of the pattern to the target is changed. In this apparatus, the deflector includes a deflection coil for generating a deflection magnetic field extending in a direction (y-axis direction) perpendicular to the predetermined direction, and correction coils for generating correction magnetic fields extending in the same direction as the deflection magnetic field at areas spaced apart from the center of the deflection magnetic field along the direction (x-axis direction) perpendicular to the direction of the deflection magnetic field.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: November 3, 1998
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji
  • Patent number: 5811801
    Abstract: An omega-type energy filter of the B-type in which a beam of charged-particles is focused three times in a direction perpendicular to the direction of magnetic fields and twice in the direction of the magnetic fields. The geometry is so designed that this B-type produces smaller aberrations and larger energy dispersion than the A-type. The filter has four sector magnets M.sub.1, M.sub.2, M.sub.3, and M.sub.4 for successively deflecting the charged-particle beam passed through an entrance aperture and for directing the beam toward an exit slit. The entrance aperture and the exit slit are arranged symmetrically with respect to a central, symmetrical plane. The sector magnets M.sub.1 and M.sub.4 are arranged symmetrically with respect to the symmetrical plane. The sector magnets M.sub.2 and M.sub.3 are arranged symmetrically with respect to the symmetrical plane. The entrance aperture and the entrance face of the sector magnet M.sub.1 are separated by a distance of L.sub.5. The exit face of the sector magnet M.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: September 22, 1998
    Assignee: JEOL Ltd.
    Inventor: Katsushige Tsuno
  • Patent number: 5793048
    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.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: August 11, 1998
    Assignee: International Business Machines Corporation
    Inventors: Paul F. Petric, Guenther O. Langner
  • Patent number: 5780859
    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.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: July 14, 1998
    Assignee: ACT Advanced Circuit Testing Gesellschaft
    Inventors: Hans-Peter Feuerbaum, Jurgen Frosien, Koshi Ueda, Toshimichi Iwai, Gerald Schonecker
  • Patent number: 5773837
    Abstract: An image transferring apparatus using a charged particle beam comprising a projection lens for transferring a pattern formed on a mask onto a target by focusing a charged particle beam passed through the mask, and a deflector for deflecting the charged particle beam passed through the mask toward a predetermined direction (x-axis direction) so that a transfer position of the pattern to the target is changed. In this apparatus, the deflector comprises a deflection coil for generating a deflection magnetic field extending in a direction (y-axis direction) perpendicular to the predetermined direction, and correction coils for generating correction magnetic fields extending in the same direction as the deflection magnetic field at areas spaced apart from the center of the deflection magnetic field along the direction (x-axis direction) perpendicular to the direction of the deflection magnetic field.
    Type: Grant
    Filed: June 10, 1997
    Date of Patent: June 30, 1998
    Assignee: Nikon Corporation
    Inventor: Mamoru Nakasuji