Abstract: An electron beam column comprises a thermal field emission electron source to generate an electron beam, an electron beam blanker, a beam shaping module, and electron beam optics comprising a plurality of electron beam lenses. In one version, the optical parameters of the electron beam blanker, beam shaping module, and electron beam optics are set to achieve an acceptance semi-angle ? of from about ¼ to about 3 mrads, where the acceptance semi-angle ? is the half the angle subtended by the electron beam at the writing plane. The beam-shaping module can also operate as a single lens using upper and lower projection lenses. A multifunction module for an electron beam column is also described.

Abstract: An electron beam source for use in an electron gun. The electron beam source includes an emitter terminating in a tip. The emitter is configured to generate an electron beam. The electron beam source further includes a suppressor electrode laterally surrounding the emitter such that the tip of the emitter protrudes through the suppressor electrode and an extractor electrode disposed adjacent the tip of the emitter. The extractor electrode comprises a magnetic disk whose magnetic field is aligned with an axis of the electron beam.

Abstract: A photocathode is capable of generating an electron beam from incident light. The photocathode comprises a light permeable support having a light receiving surface and an opposing surface. A Group III nitride layer is provided on the opposing surface of the support. The Group III nitride layer comprises at least one Group III element and nitrogen. An alkali halide layer is provided on the Group III nitride layer. The alkali halide can be a cesium halide, such as cesium bromide or iodide.

Abstract: A multiple electron beam source comprises a photon source to generate a photon beam, a lens to focus the photon beam, a photocathode having a photon receiving surface and an electron emitting surface, and an array of electron transmission gates spaced apart from the electron emitting surface of the photocathode by a distance dg. Each electron transmission gate comprises a membrane; an anode on a first surface of the membrane; an insulator on a second surface of the membrane; an aperture through the anode, insulator and membrane; and a gate electrode on the insulator. The gate electrode is positioned about the aperture and capable of receiving a gate control voltage that controls the transmission of electrons through that electron transmission gate. In one version, the multiple electron beam source comprises a photocathode stage assembly to move the photocathode relative to the array of electron transmission gates.

Abstract: An electron beam source has a photocathode with a photoemitter material having a work function, and with a beam receiving portion and an electron emitting portion. A first light source directs a first light beam onto the beam receiving portion of the photocathode to generate an electron beam from the electron emitting portion. The first light beam has a wavelength ?1 such that hc/?1 is at least about the work function of the photoemitter material, where ‘h’ is Planck's constant and ‘c’ is the speed of light. A second light source directs a second light beam onto the beam receiving portion of the photocathode, such as onto the beam receiving portion, to stabilize the electron beam. The second light beam having a wavelength ?2 such that hc/?2 is less than about the work function of the photoemitter material.

Abstract: An electron beam source has a photocathode with a photoemitter material having a work function, and with a beam receiving portion and an electron emitting portion. A first light source directs a first light beam onto the beam receiving portion of the photocathode to generate an electron beam from the electron emitting portion. The first light beam has a wavelength &lgr;1 such that hc/&lgr;1 is at least about the work function of the photoemitter material, where ‘h’ is Planck's constant and ‘c’ is the speed of light. A second light source directs a second light beam onto the beam receiving portion of the photocathode, such as onto the beam receiving portion, to stabilize the electron beam. The second light beam having a wavelength &lgr;2 such that hc/&lgr;2 is less than about the work function of the photoemitter material.

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: 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.