Abstract: A multifunction module for an electron beam column comprises upper and lower electrodes, and a central ring electrode. The upper and lower electrodes have multipoles and are capable of deflecting, or correcting an aberration of, an electron beam passing through the electrodes. A voltage can be applied to the central ring electrode independently of the voltages applied to the upper and lower electrodes to focus the electron beam on a substrate.

Abstract: Methods and apparatus to facilitate the measurement of the amount of scattered electrons collected by an anti-fogging baffle arrangement are provided. For some embodiments, by affixing a lead to an electrically isolated (floating) portion of the baffle arrangement, the amount of scattered electrons collected thereby may be read out, for example, as a current signal. Thus, for such embodiments, the baffle arrangement may double as a detector, allowing an image of surface (e.g., a mask or substrate surface) to be generated.

Abstract: A multifunction module for an electron beam column comprises upper and lower electrodes, and a central ring electrode. The upper and lower electrodes have multipoles and are capable of deflecting, or correcting an aberration of, an electron beam passing through the electrodes. A voltage can be applied to the central ring electrode independently of the voltages applied to the upper and lower electrodes to focus the electron beam on a substrate.

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 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: Embodiments of the present invention may be utilized to improve electron beam deflection. One embodiment provides an electrostatic deflection system with electrodes that minimize aberrations and to achieve vertical incidence simultaneously. By using at least two stages of deflection for a deflection direction, the present invention allows the deflected electron beam to pass a back focal plane of an objective lens while deflection capacitors are not disposed across the back focal plane. As a result, deflection electrodes can have an angle of 120° to minimize aberrations and simultaneously achieve vertical incidence of the electron beam on a target to avoid distortions or changes in magnification with height variations of the target or focus variations.

Abstract: An apparatus and method for deflecting electron beams with high precision and high throughput. At least one electrode of a deflecting capacitor is connected to a signal source via a coaxial cable. A termination resistor is further connected to the coaxial cable and the electrode at the joint of the coaxial cable and the electrode. The termination resistor has a resistance matched to the impedance of the coaxial cable and the electrode has an impedance matched to half of the impedance of the coaxial. The deflecting capacitors of the present invention have a minimized loss of precision due to eddy current. The spacing of electrodes in the deflecting capacitors is reduced by a factor of approximately two compared to the state-the-art system.

Abstract: An immersion lens for a charged particle beam lithography system includes a magnetically floating shield that limits a deflection magnetic field from creating eddy currents in electrically conductive components of the system downstream from the shield. The surface of the shield lies parallel or approximately parallel to a magnetic equipotential surface of the focusing magnetic field so that the shield does not affect the focusing magnetic field. The shield is, e.g., a ferrite disk or a hollow ferrite cone defining a central bore for passage of the charged particle beam.

Abstract: An electron source has an anode and a cathode that is capable of being negatively biased relative to the anode, the cathode having an electron emitting portion and a cathode axis. An electromagnetic radiation source is adapted to generate an electromagnetic radiation beam to heat the cathode. A lens is adapted to direct the electromagnetic radiation beam onto the cathode, the lens having a lens axis that forms an acute angle with, or is substantially parallel to, the cathode axis of the electron emitting portion.

Abstract: An immersion lens for a charged particle beam lithography system includes a magnetically floating shield that limits a deflection magnetic field from creating eddy currents in electrically conductive components of the system downstream from the shield. The surface of the shield lies parallel or approximately parallel to a magnetic equipotential surface of the focusing magnetic field so that the shield does not affect the focusing magnetic field. The shield is, e.g., a ferrite disk or a hollow ferrite cone defining a central bore for passage of the charged particle beam.

Abstract: An immersion lens for a charged particle beam lithography system includes a magnetically floating shield that limits a deflection magnetic field from creating eddy currents in electrically conductive components of the system downstream from the shield. The surface of the shield lies parallel or approximately parallel to a magnetic equipotential surface of the focusing magnetic field so that the shield does not affect the focusing magnetic field. The shield is, e.g., a ferrite disk or a hollow ferrite cone defining a central bore for passage of the charged particle beam.

Abstract: A blanker assembly for an electron beam column obtains synchronicity between the beam blanking signal propagating through its blanker plates and the associated electron beam which is being blanked. Since the blanking signal travels faster than does the electron beam, the desired synchronicity is achieved by use of a dielectric material for propagating the blanking signal to slow down this signal to match the electron beam velocity. By using a dielectric material for high frequency (RF) blanking signals, there will be less signal reflection and greater blanking accuracy because the electron beam is continuously deflected. The blanker plates each include a substance having a relatively low dielectric constant for proipagating the blanking signal between an upper deflection region. The relative slowness of the propagation of the blanking signal between the upper and lower deflection regions provides a delay effect so as to synchronize the blanking signal with the associated electron beam.

Abstract: An electron source has an anode and a cathode that is capable of being negatively biased relative to the anode, the cathode having an electron emitting portion and a cathode axis. An electromagnetic radiation source is adapted to generate an electromagnetic radiation beam to heat the cathode. A lens is adapted to direct the electromagnetic radiation beam onto the cathode, the lens having a lens axis that forms an acute angle with, or is substantially parallel to, the cathode axis of the electron emitting portion.

Abstract: An enhanced electron source in most respects similar to a standard cathode assembly for an electron gun includes an electron emitter surrounded by a suppressor electrode, the emitted electrons passing through an extractor electrode. Additionally, the suppressor electrode includes a small ring shaped permanent magnet surrounding the opening in the suppressor electrode through which the emitter tip protrudes. The resulting magnetic field is aligned with the beam axis, and includes a tail which forms a very short focal length magnetic lens immediately following the emitter tip. This magnetic field collimates the electron beam before it enters the downstream electrostatic gun lens, thus increasing the effective angular intensity of the cathode assembly. The aberrations of this collimating lens are very low so that its useful brightness is not reduced. Also the influence of guns lens aberrations is reduced because a smaller aperture angle in the gun lens may be used to obtain higher beam current.

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.

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.

Abstract: Disclosed is a biassing scheme for a beam position location apparatus (50) which comprises electron detector diodes (52) in an electron beam lithography machine (10) such that the detector diodes (52) deposit fewer secondary electrons (62) on a substrate (16) being processed by the electron beam (22) and thus reduce or eliminate any charge buildup on said substrate which deflect the electron beam (22) causing pattern distortion.

Abstract: A composite objective lens for a particle beam lithographic system having deflection coils within the bore of the lens, a solenoidal excitation lens coil, a first set of two or more cylindrical pole pieces with a lens gap and a second set of cylindrical pole pieces arranged concentrically outside the first pole pieces but within the excitation lens coil. The second set of pole pieces is constructed of a high saturation material such as iron with a lens gap coextensive with the gap in the first set of pole pieces. The return flux from the deflection coils is carried by the inner cylindrical pole pieces only, while the flux generated by the lens coil is shared by both the inner and outer pole pieces. With this arrangement the linear relationship between the axial field strength and excitation current is maintained at all points along the axis of the lens, and saturation of the inner pole piece is avoided.