Abstract: The technique of measuring the spotsize and edgewidth of an electron beam by incrementally scanning the beam through discrete scan locations across a sharp edge is improved by processing the resulting beam current signals directly rather than the differentiated beam current signal. A linear regression is performed on beam current data points expected to fall in the linear portion of the beam current versus beam position characteristic in order to provide a linear approximation of the overall characteristic. Extrapolation of the linear function to its intersections with the maximum (I.sub.1) and minimum (I.sub.0) beam current levels yields corresponding beam positions Z.sub.B and Z.sub.A, such that (Z.sub.B -Z.sub.A) is a measure of spotsize in the scan direction. Edgewidth between the twelve and eighty-eight percent amplitude levels is obtained by locating measured beam currents at incremental scan locations on both sides of beam positions Z.sub.A and Z.sub.

Abstract: A multi leaf collimator for a radiation beam the particles of which is selected from the group consisting of high energy photons, electrons, protons and heavy ions which are emitted from a small effective radiation source. The collimator comprises low hight, elongated, curved, in cross section wedge-shaped leaves arranged side by side in opposed pairs. The configuration is such that the parts of the surfaces intersecting the irradation field will always be directed generally towards the radiation source. A protective casing surrounding a frame on which the collimator is mounted can be filled with helium gas to optimize the collimator for use with electron and photon beams in the energy range from 1 up to 50 MeV. The individual settings of the leaves are supervised by a TV-camera which also can be used to set the leaves in predetermined positions.

Abstract: A multi-stage valve having a valve housing containing an inlet port and an outlet port that communicate through means of an elongated chamber formed in the housing. An outer sealing unit is mounted in the chamber and is adapted to close in sealing contact against one of the ports. A control orifice is passed through the first sealing unit to restrict the flow through the port when the unit is sealed thereagainst. A second inner sealing unit is mounted in the chamber behind the outer unit and is arranged to close thereagainst to seal the orifice. The two units are coupled by a lost motion mechanism which permits the sealing units to close in sequence between a fully closed position, an intermediate position wherein the flow through the valve is restricted by the orifice and a fully opened position wherein the flow through the valve is unrestricted.

Abstract: A method of measuring a resist pattern in which size and/or position of a latent image formed in the resist film by irradiation, is measured by Auger electron spectroscopy or a like method. With this method, since there is no need to develop when the resist pattern is not acceptable, manufacturing costs are decreased. By adjusting developing time by replying upon the data from the latent image, furthermore, high yield processing can be effected more precisely.

Abstract: An improved scanning tunneling microscope comprising a semiconductor chip into which slots are etched to form a central portion linked by a first pair of stripes to an intermediate portion, which in turn is linked by a second pair of stripes to the main body of the chip. The pairs of stripes have mutually orthogonal directions to allow the center portion to perform movements in the x- and y-directions under the control of electrostatic forces created between the stripes and their opposite walls. The center portion has formed into it at least one tongue carrying an integrated, protruding tunnel tip which is capable of being moved in the z-direction by means of electrostatic forces between said tongue and the bottom of a cavity below the tongue.

Abstract: A radiation dispersing cavity has its interior surface covered by a plurality of deformations, each of which acts as a dispersing element which is small with respect to the effective diameter of the cavity and yet large with respect to the wavelengths processed by the integrating cavity. The interior surface of the cavity is coated with a material which provides the proper reflectivity for the wavelengths of interest. The interior of the cavity is covered with at least two different sets of interlocking deformations producing at least two different apparent planes of reflection. Use of alternating concave-inward, concave-outward deformations facilitates smooth transitions between deformations, preventing development of hot spots at sharp discontinuities.

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

Abstract: Negative ion source making it possible to produce an intense beam of negative ions, particularly of hydrogen and deuterium, as well as negative ions of other species. According to the main feature of this negative ion source, the number and distribution of the permanent magnets forming the magnetic multicusp confinement is chosen in such a way that the confinement time of the primary electrons is between 10.sup.-7 and 10.sup.-6 second and the thermionic electron emitters are located in the multicusp magnetic field between the saddle point of the magnetic field, formed by two adjacent permanent magnets and the center of the plasma in the vicinity of said saddle points. It is advantageously applied to the production of high-energy neutral atom beams used e.g. as an effective means for heating plasmas, produced in magnetic confinement fusion means.

Abstract: Electron detector apparatus and method for detecting secondary electrons released from a body, of particular utility in testing integrated circuits in an operational state. The apparatus utilizes a magnetic lens having an axis of symmetry, for producing a magnetic field that progressively weakens along the axis, so that the secondary electrons travel through the magnetic lens in progressively elongated helical paths and approach an electron retarding means, for example a planar grid, at approach angles to the direction of the axis such that their approach speeds along the axis are substantially equal to their actual speeds. The secondary electrons are collected after passage through the retarding means.

Abstract: An apparatus for continuous corona treatment of materials, such as wire. An electrode is helically wound about a tubular glass dielectric, and the electrode is attached to a source of high voltage, high frequency power. In order to facilitate rapid passage of the treated material through the glass tube, blocks with internal pulleys are mounted at either end of the tube.

Abstract: In a mass spectrometer comprising an ion gun for radiating an ion beam onto a surface of an object to make the surface emit secondary ions, a detector for the secondary ions, and a directing member for directing the secondary ions to the detector, a specific energy bandwidth is defined in an energy distribution of the secondary ions in consideration of a peak of the energy distribution. An analyzable energy range is expanded to at least twice the specific energy bandwidth by the use of an expanding member coupled to the directing member. The expanding member may be used to expand a transmissible bandwidth of an energy filter included in the directing member by raising a resolution and a center transmission energy. The expanding member may be used to raise a maximum analyzable energy of a quadrupole mass filter included in the mass filter. Specifically, the expanding member may be implemented by changing a length of each electrode member of the mass filter and/or a frequency of an a.c.

Abstract: The dimensions of the cross section of an electron beam emitted from a beam source are changed by deflectors interposed between a pair of aperture masks and are position-corrected by beam position correction deflectors. The electron beam is then irradiated onto a wafer. In accordance with beam dimension signals from a CPU, a correction signal generating circuit supplies correction signals to a beam position correction circuit. The circuit supplies beam position correction signals to the deflectors.

Abstract: Apparatus is disclosed herein, for converting laser energy to thermal energy for a variety of purposes, which includes a conical laser beam collector for gathering or receiving impinging beams or rays that has a plurality of coaxially disposed annular shoulders arranged either along the external or internal surfaces of the collector adapted directly to receive the laser beams or rays. A liquid circulating system includes a cylinder housing the conical collector having a plurality of coaxial coils arranged about its external surface and, in one version, joined with an internal coiled spiral carried on the conical collector. The liquid circulating system serves as a heat exchanger to convert the heat gathered by the conical collector into superheated liquid carried by the liquid circulating system for ultimate use in prime mover or generator applications.

Abstract: A deflecting magnet assembly for scanning an incident beam of charged particles in a scanning electron beam computed tomography scanner. The configuration (including angular orientation and coil end connection geometry) of the coils which comprise the magnet is selected to approximate the field of a pure dipole. In addition, a magnetic shield is used which equalizes the effective radii of the constituent coils and thereby simplifies construction of the assembly.

Abstract: An apparatus and method for maintaining an optical element at a sufficiently high temperature during transmission of radiation by the optical element to prevent radiation degradation of the optical element by an increase in the absorption of at least one wavelength of the radiation. The material of the optical element is such that the absorption of the wavelength(s) concerned temporarily decreases upon annealing the optical element. The optical element may be kept at the temperature required by a wide variety of heating techniques, including gas convection heating, direct contact heating, and radiant heating. The heated optical element may be employed in optical systems for transmitting radiation from a source of radiation to a target to be exposed to this radiation.

Abstract: In an Auger electron spectrometer for use in analyzing a surface of an object by the use of Auger electrons resulting from impingement of an electron beam, an electron gun comprises an electron beam source for generating the electron beam and an electron lens system for guiding the electron beam towards the surface. The electron lens system comprises a combination of a condenser lens and a permanent magnet member nearer to the surface than the condenser lens. The permanent magnet member may comprise either a plurality of permanent magnet pieces radially and azimuthally spaced apart from one another or a single permanent magnet piece. An ion gun may be disposed in the vicinity of the electron gun to generate an ion beam oblique to the electron beam and substantially concurrent with the electron beam on the surface. Magnetic pole pieces may be attached to each permanent magnet piece and bypassed to control a magnetic field generated by each permanent magnet piece.

Abstract: A closure system for a storage cask containing spent nuclear fuel has redundant mechanical seals to temporarily close the cask during development, testing, and refinement thereof, when it is occasionally necessary to open the cask, and redundant welded seals to supplement the mechanical seals when development is completed and the cask is permanently sealed during long-term storage. The closure system includes a primary cover which cooperates with an O-ring to provide a mechanical seal and which includes a canopy element that can be welded to the cask base element if a permanent seal is desired. The closure system also includes a secondary cover which cooperates with an additional O-ring to provide an additional mechanical seal and which is configured to receive an additional canopy element in the event that an additional welded seal is desired. The closure system permits the cask to be developed, tested, and refined using the same closure system that will be installed during actual use.

Abstract: A transitory or temporary storage for highly radioactive waste, in which the transitory storage incorporates containers for the receipt of the waste, and a cooling system for the discharge of the heat which is produced during the storage of the waste. The cooling system incorporates a cooling air duct, as well as a coolant circuit for a coolant which is conveyed in a closed circuit between coolant conduits which conduct off heat generated in the storage space and a heat sink arranged externally of the storage space.

Abstract: A method for measuring a low-frequency signal progression at a measuring point of a specimen by use of an electron probe. A load on the circuit is kept as low as possible by employing a pulsed electron probe during a search of the measuring points. The pulsed electron probe may also be employed for actual measurement. By providing a pulse repitition frequency of the electron probe which is independant of the operating frequency of the circuit specimen, a phase shift of the primary electron pulses relative to the low-frequency signal progression is not necessary for real time measurement of the low-frequency signal progression.

Abstract: An electron image projector for transferring mask patterns onto a semiconductor wafer comprises a patterned photoemissive cathode mask and a target formed by the semiconductor wafer coated with an electron sensitive resist. A patterned electron beam is projected from the cathode onto the target with unity magnification by acceleration with a uniform electric field E and focussing by a uniform magnetic field H. The electric field E is established between the cathode and an electron permeable anode grid situated between the cathode and the target. For fast alignment with low power consumption, beam deflection is achieved electrostatically. The electrostatic deflection plates which may be integral with the anode grid or form part of a further grid, are arranged for deflecting at least part of the beam as it travels from the anode grid to the target. In one arrangement to correct for misalignment, the entire beam is deflected in the same direction.