The present application discloses methods, systems and devices for using charged particle beam tools to pattern and inspect a substrate. The inventors have discovered that it is highly advantageous to use patterns generated using the Hadamard transform as alignment and registration marks (Hadamard targets) for multiple-column charged particle beam substrate processing and inspection tools. Hadamard targets can be written to a substrate using charged particle beams performing, for example, resist-based lithography or resist-less direct processing. High-order Hadamard targets can also be patterned and imaged to obtain superior column performance metrics for applications such as super-rapid beam calibration DOE, column matching, and column performance tracking. Hadamard target blocks can be written highly locally to electrically functional pattern portions, or integrated into said pattern portions, thereby enabling re-registration local and contemporaneous to writing and improving beam targeting accuracy following re-registration. Superior alignment and registration, and column parameter optimization, allow significant yield gains.

Apparatus and methods for the alignment of a charged-particle beam with an optical beam within a charged-particle beam microscope, and to the focusing of the optical beam are disclosed. An embodiment includes a charged-particle beam microscope having one or more charged-particle beams, such as an electron beam, and one or more optical beams provided by an optical-beam accessory that is mounted in or on the charged-particle beam microscope. This accessory is integrated into a nanomanipulator system, allowing its focus location to be moved within the microscope. The apparatus includes a two-dimensional pixelated beam locator such as a CCD or CMOS imaging array sensor. The image formed by this sensor can then be used to manually, or automatically in an open or closed loop configuration, adjust the positioning of one or more charged-particle beams or optical beams to achieve coincidence of such beams or focus of one or more such beams.

The disclosure relates to a low energy electron microscopy. The electron microscopy includes a vacuum chamber; an electron gun used to emit electron beam; a diffraction chamber; an imaging device; a sample holder used to fix two-dimensional nanomaterial sample; a vacuum pumping device; and a control computer. The electron beam transmits the sample to form a transmission electron beam and diffraction electron beam. The control computer includes a switching module to switch the work mode between a large beam spot diffraction imaging mode and small beam spot diffraction imaging mode.

By switching between a plurality of image transfer units based on a state of a stage and using the switched image transfer unit, traceability of stage movement and tolerance to communication failure can be improved. A first image transfer protocol is a protocol of which reliability is higher than reliability of a second image transfer protocol, and a switch unit may select a first image transfer unit in a case where it is determined that a state of a stage is a state in which the stage is stopping. A second image transfer unit is a protocol of which a transfer speed is higher than a transfer speed of the first image transfer protocol, and the switch unit may select the second image transfer unit in a case where it is determined that the state of the stage is a state in which the stage is moving.

Electrostatic lenses for focusing a beam of charged particles, and in particular an electron beam, are used especially in the electron guns of electron microscopes or electron-beam lithography apparatuses. The present disclosure improves the possibilities for focusing the particle beam, in particular an electron beam emitted by a cathode. The lens comprises at least one conducting electrode having at least one through-opening for the passage of an electron beam. Different electric fields are set up upstream and downstream of the opening. The passage opening is at least partially closed by a planar or curved thin membrane of semi-conducting material that is transparent to electrons and has a high dielectric permittivity. Structuring the membrane (holes or thickened portions of electrodes deposited on the membrane) makes it possible to correct lens aberration defects.

A method of measuring an overlay offset using a scanning electron microscope system includes: scanning an in-cell region, which includes a lower structure and an upper structure stacked in a sample, using a primary electron beam with a landing energy of at least 10 kV; detecting electrons emitted from the scanned in-cell region; and measuring an overlay offset with respect to overlapping patterns included in the in-cell region using an image of the in-cell region that is generated based on the detected electrons emitted from the scanned in-cell region.

A system that generates short charged particle packets or pulses (e.g., electron packets) without requiring a fast-switching-laser source is described. This system may include a charged particle source that produces a stream of continuous charged particles to propagate along a charged particle path. The system also includes a charged particle deflector positioned in the charged particle path to deflect the stream of continuous charged particles to a set of directions different from the charged particle path. The system additionally includes a series of beam blockers located downstream from the charged particle deflector and spaced from one another in a linear configuration as a beam-blocker grating. This beam-blocker grating can interact with the deflected stream of charged particles and divide the stream of the charged particles into a set of short particle packets. In one embodiment, the charged particles are electrons. The beam blockers can be conductors.

Methods and apparatus for modulating a particle pulse include a succession of Hermite-Gaussian optical modes that effectively construct a three-dimensional optical trap in the particle pulse's rest frame. Optical incidence angles between the propagation of the particle pulse and the optical pulse are tuned for improved compression. Particles pulses that can be modulated by these methods and apparatus include charged particles and particles with non-zero polarizability in the Rayleigh regime. Exact solutions to Maxwell's equations for first-order Hermite-Gaussian beams demonstrate single-electron pulse compression factors of more than 100 in both longitudinal and transverse dimensions. The methods and apparatus are useful in ultrafast electron imaging for both single- and multi-electron pulse compression, and as a means of circumventing temporal distortions in magnetic lenses when focusing ultra-short electron pulses.

This invention provides a charged particle source, which comprises an emitter and means of generating a magnetic field distribution. The magnetic field distribution is minimum, about zero, or preferred zero at the tip of the emitter, and along the optical axis is maximum away from the tip immediately. In a preferred embodiment, the magnetic field distribution is provided by dual magnetic lens which provides an anti-symmetric magnetic field at the tip, such that magnetic field at the tip is zero.

This invention provides a charged particle source, which comprises an emitter and means of generating a magnetic field distribution. The magnetic field distribution is minimum, about zero, or preferred zero at the tip of the emitter, and along the optical axis is maximum away from the tip immediately. In a preferred embodiment, the magnetic field distribution is provided by dual magnetic lens which provides an anti-symmetric magnetic field at the tip, such that magnetic field at the tip is zero.