Abstract: An electron beam lithography system has an electron gun including at least one laser that is operable in a first mode to generate electrons for lithography. The electron beam lithography system is operable in a second mode to regenerate the photocathode of the electron gun by application of the laser. The photocathode includes a layer of cesium telluride.

Abstract: One embodiment disclosed is an electron beam apparatus for examination of a specimen. The apparatus includes a photocathode source, an objective lens, a beam separator, and a projection lens. The photocathode source generates a primary electron beam with reduced energy spread. The low energy spread beam is focused onto the specimen by the objective lens. The beam separator separates a scattered electron beam from the primary electron beam, and the projection lens images the scattered electron beam. Software routines may analyze the image data for purposes of automated inspection or review.

Abstract: One embodiment disclosed relates to a method for inspecting or reviewing a magnetized specimen using an automated inspection apparatus. The method includes generating a beam of incident electrons using an electron source, biasing the specimen with respect to the electron source such that the incident electrons decelerate as a surface of the specimen is approached, and illuminating a portion of the specimen at a tilt with the beam of incident electrons. The specimen is moved under the incident beam of electrons using a movable stage of the inspection apparatus. Scattered electrons are detected to form image data of the specimen showing distinct contrast between regions of different magnetization. The movement of the specimen under the beam of incident electrons may be continuous, and data for multiple image pixels may be acquired in parallel using a time delay integrating detector.

Abstract: In accordance with one embodiment, the disclosure pertains to an apparatus for inspection of substrates. The apparatus includes at least a dual-energy e-beam source, an energy-dependent dispersive device, a beam separator, and an objective lens. The dual-energy e-beam source is configured to generate both a higher-energy e-beam component and a lower-energy e-beam component. Said two components exit the dual-energy e-source co-axially. The energy-dispersive device is configured to introduce dispersion between the two components. The components exit the dispersive device at different angles of trajectory. The beam separator is configured to receive the two dispersed components and substantially cancel the dispersion previously introduced by the dispersive device. As a result, the two components are rejoined in trajectory. Finally, the objective lens configured to focus said two rejoined components onto an area of the substrate.

Abstract: One embodiment disclosed pertains to a method for inspecting a substrate. The method includes inserting the substrate into a holding place of a substrate holder, moving the substrate holder under an electron beam, and applying a voltage to a conductive element of the substrate holder. The voltage applied to the conductive element reduces a substrate edge effect. Another embodiment disclosed relates to an apparatus for holding a substrate that reduces a substrate edge effect. The apparatus includes a holding place for insertion of the substrate and a conductive element. The conductive element is positioned so as to be located within a gap between an edge of the holding place and an edge of the substrate.

Abstract: One embodiment disclosed relates to a method for inspecting or reviewing a magnetized specimen using an automated inspection apparatus. The method includes generating a beam of incident electrons using an electron source, biasing the specimen with respect to the electron source such that the incident electrons decelerate as a surface of the specimen is approached, and illuminating a portion of the specimen at a tilt with the beam of incident electrons. The specimen is moved under the incident beam of electrons using a movable stage of the inspection apparatus. Scattered electrons are detected to form image data of the specimen showing distinct contrast between regions of different magnetization. The movement of the specimen under the beam of incident electrons may be continuous, and data for multiple image pixels may be acquired in parallel using a time delay integrating detector.

Abstract: A photocathode as a source of electron beams, having a substrate of optically transmissive diamond and a photoemitter. A photocathode with a single emitting region provides a single electron beam; a photocathode with multiple emitting regions provides multiple electron beams. The photoemitter is positioned on the side of the diamond substrate opposite the surface on which the illumination is incident, and has an irradiation region at the contact with the optically transmissive diamond, and an emission region opposite the irradiation region, these regions being defined by the path of the illumination. The diamond substrate at the irradiation region/emission region interface conducts heat away from this focused region of illumination on the photocathode. Alternately, a diamond film is used for heat conduction, while another material is used as a substrate to provide structural support.

Abstract: One embodiment disclosed relates to a method for inspecting or reviewing a magnetized specimen using an automated inspection apparatus. The method includes generating a beam of incident electrons using an electron source, biasing the specimen with respect to the electron source such that the incident electrons decelerate as a surface of the specimen is approached, and illuminating a portion of the specimen at a tilt with the beam of incident electrons. The specimen is moved under the incident beam of electrons using a movable stage of the inspection apparatus. Scattered electrons are detected to form image data of the specimen showing distinct contrast between regions of different magnetization. The movement of the specimen under the beam of incident electrons may be continuous, and data for multiple image pixels may be acquired in parallel using a time delay integrating detector.

Abstract: An electron beam lithography system includes a laser for generating a laser beam, and a beam splitter for splitting the laser beam into a plurality of light beams. The intensity of the light beams is individually modulated. The light beams are of sufficient energy such that, when they impinge on a photocathode, electrons are emitted. Modulation of the light beams controls modulation of the resulting electron beams. The electron beams are provided to an electron column for focusing and scanning control. Finally, the electron beams are used to write a scanning surface, for example, using an interlaced writing strategy.

Abstract: The microcolumn configuration of the present invention provides for emission noise reduction through the use of a screened beam-limiting aperture for monitoring the electron beam current. This novel approach utilizes a screening aperture located between the emitter and the beam-limiting aperture, which screening aperture collects most of the current transmitted by the first lens of the electron beam column. In order to achieve good noise suppression, the screening aperture should let through only the portion of the beam where the electrons are correlated. The current collected by the beam-limiting aperture is then used as a reference signal in the image processing. The elimination of this noise increases the detection sensitivity of an inspection tool. This reduces the total number of required pixels and therefore increases the throughput of the tool.

Abstract: A method and system for electron beam lithography at high throughput with shorter electron beam column length, reduced electron-electron interactions, and higher beam current. The system includes a photocathode having a pattern composed of a periodic array of apertures with a specific geometry. The spacing of the apertures is chosen so as to maximize the transmission of the laser beam through apertures significantly smaller than the photon wavelength. The patterned photocathode is illuminated by an array of laser beams to allow blanking and gray-beam modulation of the individual beams at the source level by the switching of the individual laser beams in the array. Potential applications for this invention include electron beam direct write on wafers and mask patterning.

Abstract: An electron beam lithography system has an electron gun including at least one laser that is operable in a first mode to generate electrons for lithography. The electron beam lithography system is operable in a second mode to regenerate the photocathode of the electron gun by application of the laser. The photocathode includes a layer of cesium telluride.

Abstract: An electron beam lithography system includes a laser for generating a laser beam, and a beam splitter for splitting the laser beam into a plurality of light beams. The intensity of the light beams is individually modulated. The light beams are of sufficient energy such that, when they impinge on a photocathode, electrons are emitted. Modulation of the light beams controls modulation of the resulting electron beams. The electron beams are provided to an electron column for focusing and scanning control. Finally, the electron beams are used to write a scanning surface, for example, using an interlaced writing strategy.

Abstract: A moving photoconverter device that converts an incident light image into an equivalent electron or other charged particle beam image. The moving photoconverter is ring shaped and is rotated by using a motor such that the incident light image exposes a moving photoconverter surface. The photoconverter may additionally or alternatively move in an X-Y motion or radially. Continuous regeneration is provided at a site remote from the region of moving photoconverter device that converts an incident light image into an equivalent electron or other charged particle beam image.

Abstract: An electron beam imaging apparatus capable of projecting an electron beam image on a substrate comprises a vacuum chamber having a wall and a substrate support. An electron beam source, modulator, and scanner is provided to generate, modulate, and scan one or more electron beams across the substrate. A controller is capable of generating or receiving an electrical signal to communicate with the electron beam source, modulator or scanner. One or more signal convertors are capable of converting the electrical signal to an optical signal and vice versa, the signal convertors located on either side of the wall.

Abstract: Multiple beam electron beam lithography uses an array of vertical cavity surface emitting lasers (VCSELS) to generate laser beams, which are then converted to electron beams using a photocathode. The electron beams are scanned across a semiconductor substrate or lithography mask to imprint a pattern thereon. The use of VCSELs simplifies the design of the electron beam column and improves the throughput and writing resolution of the lithography system.

Abstract: An electron source is disclosed in which control signals having transition times less than about 10 nanoseconds and electrically isolated from a gated photocathode control an electron beam supplied by the gated photocathode. In one embodiment, the electron source includes a transmissive substrate, a photoemitter on the substrate, a gate insulator on the photoemitter, a gate electrode on the gate insulator, a housing enclosing the photoemitter and the gate electrode, a light source located outside the housing, and a detector located in the housing to receive light from the light source. The detector is electrically coupled to control a voltage applied to one of the gate electrode or the photoemitter.

Abstract: A photocathode emitter as a source of electron beams, having an optically transmissive substrate patterned to define a protrusion, heat conducting material occupying the space surrounding the protrusion, and a photoemitter layer over the protrusion. The photoemitter is positioned on the side of the substrate opposite the surface on which the illumination is incident, and has an irradiation region at the contact with the top of the protrusion patterned on the substrate, and an emission region opposite the irradiation region, these regions being defined by the path of the illumination. The heat conducting material around the protrusion conducts heat away from this focused region of illumination on the photocathode to allow higher currents to be achieved from the photocathode and thus permits higher throughput rates in applications including electron beam lithography. In one version, the photocathode is fabricated using microfabrication techniques, to achieve a small emission spot size.

Abstract: A photocathode having a gate electrode so that modulation of the resulting electron beam is accomplished independently of the laser beam. The photocathode includes a transparent substrate, a photoemitter, and an electrically separate gate electrode surrounding an emission region of the photoemitter. The electron beam emission from the emission region is modulated by voltages supplied to the gate electrode. In addition, the gate electrode may have multiple segments that are capable of shaping the electron beam in response to voltages supplied individually to each of the multiple segments.

Abstract: A photocathode having a gate electrode so that modulation of the resulting electron beam is accomplished independently of the laser beam. The photocathode includes a transparent substrate, a photoemitter, and an electrically separate gate electrode surrounding an emission region of the photoemitter. The electron beam emission from the emission region is modulated by voltages supplied to the gate electrode. In addition, the gate electrode may have multiple segments that are capable of shaping the electron beam in response to voltages supplied individually to each of the multiple segments.