Abstract: Systems and methods of inspecting a sample using a multi charged-particle beam apparatus with enhanced probe current of beamlets are disclosed. The apparatus may include a charged-particle source, a first condenser lens configured to focus the plurality of charged-particle beams to form a beam crossover at a crossover point and a second condenser lens configured to collimate the focused plurality of charged-particle beams, wherein the crossover point is formed between the first and the second condenser lens along the primary optical axis, and wherein an adjustment of a position of the crossover point causes an adjustment of a beam sizes of the plurality of charged-particle beams. The position of the crossover point may be adjusted by varying the excitation of one or more condenser lenses, or by electrically moving the principal plane positions of one or more condenser lenses.

Abstract: An apparatus includes a first charged particle beam manipulator positioned in a first layer configured to influence a charged particle beam and a second charged particle beam manipulator positioned in a second layer configured to influence the charged particle beam. The first and second charged particle beam manipulators may each include a plurality of electrodes having a first set of opposing electrodes and a second set of opposing electrodes. A first driver system electrically connected to the first set may be configured to provide a plurality of discrete output states to the first set. A second driver system electrically connected to the second set may be configured to provide a plurality of discrete output states to the second set. The first and second charged-particle beam manipulators may each comprise a plurality of segments; and a controller having circuitry configured to individually control operation of each of the plurality of segments.

Abstract: Systems and methods of observing a sample using an electron beam apparatus are disclosed. The electron beam apparatus comprises an electron source configured to generate a primary electron beam along a primary optical axis, and a first electron detector having a first detection layer substantially parallel to the primary optical axis and configured to detect a first portion of a plurality of signal electrons generated from a probe spot on a sample. The method may comprise generating a plurality of signal electrons and detecting the signal electrons using the first electron detector substantially parallel to the primary optical axis of the primary electron beam. A method of configuring an electrostatic element or a magnetic element to detect backscattered electrons may include disposing an electron detector on an inner surface of the electrostatic or magnetic element and depositing a conducting layer on the inner surface of the electron detector.

Abstract: Systems and methods are provided for compensating dispersion of a beam separator in a single-beam or multi-beam apparatus. Embodiments of the present disclosure provide a dispersion device comprising an electrostatic deflector and a magnetic deflector configured to induce a beam dispersion set to cancel the dispersion generated by the beam separator. The combination of the electrostatic deflector and the magnetic deflector can be used to keep the deflection angle due to the dispersion device unchanged when the induced beam dispersion is changed to compensate for a change in the dispersion generated by the beam separator. In some embodiments, the deflection angle due to the dispersion device can be controlled to be zero and there is no change in primary beam axis due to the dispersion device.

Abstract: A multi-beam apparatus for observing a sample with high resolution and high throughput and in flexibly varying observing conditions is proposed. The apparatus uses a movable collimating lens to flexibly vary the currents of the plural probe spots without influencing the intervals thereof, a new source-conversion unit to form the plural images of the single electron source and compensate off-axis aberrations of the plural probe spots with respect to observing conditions, and a pre-beamlet-forming means to reduce the strong Coulomb effect due to the primary-electron beam.

Abstract: Systems and methods of imaging a sample using a charged-particle beam apparatus are disclosed. The charged-particle beam apparatus may include a charged-particle source configured to generate primary charged particles, the primary charged particles forming a primary charged-particle beam along a primary optical axis, and a charged-particle detector comprising a plurality of con-centric segments of a charged-particle sensitive material configured to detect charged particles emitting from a sample after interaction of the primary charged-particle beam with the sample, wherein each segment of the plurality of concentric segments is configured to collect the emitted charged particles having a range of energy levels and a dominant energy level.

Abstract: Some disclosed embodiments include an electron detector comprising: a first semiconductor layer having a first portion and a second portion; a second semiconductor layer; a third semiconductor layer; a PIN region formed by the first, second, and third semiconductor layers; a power supply configured to apply a reverse bias between the first and the third semiconductor layers; and a depletion region formed within the PIN region by the reverse bias and configured to generate a detector signal based on a first subset of the plurality of signal electrons captured within the depletion region, wherein the second portion of the first semiconductor layer is not depleted and is configured to provide an energy barrier to block a second subset of the plurality of signal electrons and to allow the first subset of the plurality of signal electrons to pass through to reach the depletion region.

Abstract: A charged particle detector includes a plurality of sensing elements, with each sensing element being further divided into sub-sensing elements. The sub-sensing elements may be individually addressed during high-resolution image acquisition in a picture mode, and may be grouped together during high speed detection in a beam mode. The arrangement allows a selectable tradeoff between speed and resolution without introducing significant parasitic parameters.

Abstract: Systems and methods are provided for compensating dispersion of a beam separator in a single-beam or multi-beam apparatus. Embodiments of the present disclosure provide a dispersion device comprising an electrostatic deflector and a magnetic deflector configured to induce a beam dispersion set to cancel the dispersion generated by the beam separator. The combination of the electrostatic deflector and the magnetic deflector can be used to keep the deflection angle due to the dispersion device unchanged when the induced beam dispersion is changed to compensate for a change in the dispersion generated by the beam separator. In some embodiments, the deflection angle due to the dispersion device can be controlled to be zero and there is no change in primary beam axis due to the dispersion device.

Abstract: Systems and methods of mitigating Coulomb effect in a multi-beam apparatus are disclosed. The multi-beam apparatus may include a charged-particle source configured to generate a primary charged-particle beam along a primary optical axis, a first aperture array comprising a first plurality of apertures having shapes and configured to generate a plurality of primary beamlets derived from the primary charged-particle beam, a condenser lens comprising a plane adjustable along the primary optical axis, and a second aperture array comprising a second plurality of apertures configured to generate probing beamlets corresponding to the plurality of beamlets, wherein each of the plurality of probing beamlets comprises a portion of charged particles of a corresponding primary beamlet based on at least a position of the plane of the condenser lens and a characteristic of the second aperture array.

Abstract: Systems and methods of measuring of optimizing collection efficiency of secondary charged particles include a multi-beam inspection apparatus configured to scan a sample and including a lens, a detector configured to receive a plurality of secondary charged-particle beams in response to scanning the sample, and a controller including circuitry communicatively coupled to the multi-beam inspection apparatus and the detector, configured to: focus the lens to adjust sizes of secondary beam spots, wherein the secondary beam spots are formed by the plurality of secondary charged-particle beams on the detector; cause, for each secondary charged-particle beam of the plurality of secondary charged-particle beams, outlier charged particles of the each secondary charged-particle beam to not be detected by the detector; and refocus the lens to adjust currents of a portion of the plurality of secondary charged-particle beams detected by the detector, wherein the outlier charged particles do not contribute to the currents.

Abstract: Systems and methods of imaging a sample using a charged-particle beam apparatus are disclosed. The apparatus may include a charged-particle source configured to emit charged particles, the emitted charged particles forming a primary charged-particle beam along a primary optical axis; an objective lens comprising a magnetic lens; a charged-particle detector located downstream from the objective lens with respect to a path of the primary charged-particle beam and along a horizontal plane substantially perpendicular to the primary optical axis; and a voltage control plate located between the charged-particle detector and a pole-piece of the magnetic lens. The voltage control plate may comprise a horizontal portion comprising an opening; and an elongated portion extending downward from the opening with respect to the path of the primary charged-particle beam, into a hole of the charged-particle detector.

Abstract: A multi-beam apparatus for observing a sample with high resolution and high throughput and in flexibly varying observing conditions is proposed. The apparatus uses a movable collimating lens to flexibly vary the currents of the plural probe spots without influencing the intervals thereof, a new source-conversion unit to form the plural images of the single electron source and compensate off-axis aberrations of the plural probe spots with respect to observing conditions, and a pre-beamlet-forming means to reduce the strong Coulomb effect due to the primary-electron beam.

Abstract: Some embodiments are related to a method of or apparatus for forming an image of a buried structure that includes: emitting primary charged particles from a source; receiving a plurality of secondary charged particles from a sample; and forming an image based on received secondary charged particles that have an energy within a first range.

Abstract: Systems and methods of imaging a sample using a charged-particle beam apparatus are disclosed. The apparatus may include a charged-particle source configured to emit charged particles, an aperture plate configured to form a primary charged-particle beam along a primary optical axis from the emitted charged particles, a plurality of primary charged-particle beam deflectors configured to deflect the primary charged-particle beam to be incident on a surface of a sample to define a center of a field-of-view (FOV), and a controller including circuitry configured to apply a first excitation signal to a primary charged-particle beam deflector of the plurality of primary charged-particle beam deflectors to cause the primary charged-particle beam to scan a portion of the FOV of the sample, and apply a second excitation signal to cause the primary-charged particle beam deflector to compensate for an off-axis aberration of the primary charged-particle beam in the portion of the FOV.

Abstract: An improved system is disclosed for wafer outer portion inspection in a charged particle beam system, such as a scanning electron microscope (SEM). The system uses multiple conductive rings around the wafer to correct an e-field distortion occurring at the wafer outer portion. The rings are applied with different complimentary voltages in order achieve a precise compensation of the e-field distortion.

Abstract: A multi-beam apparatus for observing a sample with high resolution and high throughput is proposed. In the apparatus, a source-conversion unit forms plural and parallel images of one single electron source by deflecting plural beamlets of a parallel primary-electron beam therefrom, and one objective lens focuses the plural deflected beamlets onto a sample surface and forms plural probe spots thereon. A movable condenser lens is used to collimate the primary-electron beam and vary the currents of the plural probe spots, a pre-beamlet-forming means weakens the Coulomb effect of the primary-electron beam, and the source-conversion unit minimizes the sizes of the plural probe spots by minimizing and compensating the off-axis aberrations of the objective lens and condenser lens.

Abstract: Inspection systems and methods are disclosed. An inspection system may include a first energy source configured to provide a first landing energy beam and a second energy source configured to provide a second landing energy beam. The inspection system may also include a beam controller configured to selectively deliver one of the first and second landing energy beams towards a same field of view, and to switch between delivery of the first and second landing energy beams according to a mode of operation of the inspection system.

Abstract: Systems and methods of reducing the Coulomb interaction effects in a charged particle beam apparatus are disclosed. The charged particle beam apparatus may comprise a charged particle source and a source conversion unit comprising an aperture-lens forming electrode plate configured to be at a first voltage, an aperture lens plate configured to be at a second voltage that is different from the first voltage for generating a first electric field, which enables the aperture-lens forming electrode plate and the aperture lens plate to form aperture lenses of an aperture lens array to respectively focus a plurality of beamlets of the charged particle beam, and an imaging lens configured to focus the plurality of beamlets on an image plane. The charged particle beam apparatus may comprise an objective lens configured to focus the plurality of beamlets onto a surface of the sample and form a plurality of probe spots thereon.

Abstract: Systems and methods of providing a probe spot in multiple modes of operation of a charged-particle beam apparatus are disclosed. The method may comprise activating a charged-particle source to generate a primary charged-particle beam and selecting between a first mode and a second mode of operation of the charged-particle beam apparatus. In the flooding mode, the condenser lens may focus at least a first portion of the primary charged-particle beam passing through an aperture of the aperture plate to form a second portion of the primary charged-particle beam, and substantially all of the second portion is used to flood a surface of a sample. In the inspection mode, the condenser lens may focus a first portion of the primary charged-particle beam such that the aperture of the aperture plate blocks off peripheral charged-particles to form the second portion of the primary charged-particle beam used to inspect the sample surface.