H01J2237/1508

Method of eliminating thermally induced beam drift in an electron beam separator

These electron beam separator designs address thermally-induced beam drift in an electron-optical system. A heater coil wrapped around the beam separator unit can maintain constant power. Additional coils also can be wrapped around the beam separator in a bifilar manner, which can maintain constant power in the beam separator coils. Wien power can be determined, and then heater coil current can be determined.

SYSTEMS AND METHODS FOR CHARGED PARTICLE BEAM MODULATION
20190164721 · 2019-05-30 ·

Systems and methods for conducting charged particle beam modulation are disclosed. According to certain embodiments, a charged particle beam apparatus generates a plurality of charged particle beams. A modulator may be configured to receive the plurality of charged particle beams and generate a plurality of modulated charged particle beams. A detector may be configured to receive the plurality of modulated charged particle beams.

Method of reducing coma and chromatic aberration in a charged particle beam device, and charged particle beam device

The present disclosure provides a method of reducing coma and chromatic aberration in a charged particle beam device for providing a beam tilt of a charged particle beam. The method includes tilting the charged particle beam with a deflection assembly consisting of two or more electrostatic deflection elements, wherein at least one deflection element of the two or more deflection elements is a post-lens deflector, while the charged particle beam is guided through an essentially coma-free z-position of an objective lens, and reducing off-axis chromatic aberrations with a magnetic deflection element, wherein tilting the charged particle beam reduces coma independent of off-axis chromatic aberrations.

Measuring spherical and chromatic aberrations in cathode lens electrode microscopes

An electron microscope system and a method of measuring an aberration of the electron microscope system are disclosed. An aperture filters an electron beam at a diffraction plane of the electron microscope to pass through electrons having a selected energy and momentum. A displacement of an image of the passed electrons is measured at a detector in an image plane of the electron microscope. An aberration coefficient of the electron microscope is determined from the measured displacement and at least one of the energy and momentum of the passed electrons. The measured aberration can be used to alter a parameter of the electron microscope or an optical element of the electron microscope to thereby control the overall aberration of the electron microscope.

SCANNING ELECTRON MICROSCOPE

The present invention enlarges a range of movement of field of view by beam deflection with a simple deflector configuration and suppresses deterioration of a signal electron detection rate caused by the beam deflection. A scanning electron microscope according to the present invention is provided with a first deflection field setting module that sets plural deflectors to move a scanning area on a specimen by a primary electron beam to a position deviated from an axis extended from an electron source toward the center of an objective lens and a second deflection field setting module that sets the plural deflectors so that trajectories of signal electrons are corrected without changing the scanning area set by the first deflection field setting module. The control unit controls the plural deflectors by adding a setting value set by the second deflection field setting module to a setting value set by the first deflection field setting module.

MEASURING SPHERICAL AND CHROMATIC ABERRATIONS IN CATHODE LENS ELECTRODE MICROSCOPES
20180337017 · 2018-11-22 ·

An electron microscope system and a method of measuring an aberration of the electron microscope system are disclosed. An aperture filters an electron beam at a diffraction plane of the electron microscope to pass through electrons having a selected energy and momentum. A displacement of an image of the passed electrons is measured at a detector in an image plane of the electron microscope. An aberration coefficient of the electron microscope is determined from the measured displacement and at least one of the energy and momentum of the passed electrons. The measured aberration can be used to alter a parameter of the electron microscope or an optical element of the electron microscope to thereby control the overall aberration of the electron microscope.

Method and system for aberration correction in an electron beam system

An electron-optical system for performing electron microscopy is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a source lens, a condenser lens and an objective lens disposed along an optical axis. The system includes a first Wien filter disposed along the optical axis and a second Wien filter disposed along the optical axis. The first Wien filter and the second Wien filter are disposed between the source lens and the objective lens. The first Wien filter is configured to correct chromatic aberration in the primary beam. The system also includes a detector assembly configured to detect electrons emanating from the surface of the sample.

Scanning Transmission Electron Microscope

A scanning transmission electron microscope is adapted to acquire high quality precession electron diffraction (PED) patterns by means of separated scanning deflectors and precession deflectors. Magnetic or electrostatic deflectors may be used for scanning and for precession. This enables independent optimization of parameters for each deflection system to achieve a broad operating range simultaneously for both deflection systems.

Method and System for Aberration Correction in an Electron Beam System
20180158644 · 2018-06-07 ·

An electron-optical system for performing electron microscopy is disclosed. The system includes an electron beam source configured to generate a primary electron beam. The system includes a source lens, a condenser lens and an objective lens disposed along an optical axis. The system includes a first Wien filter disposed along the optical axis and a second Wien filter disposed along the optical axis. The first Wien filter and the second Wien filter are disposed between the source lens and the objective lens. The first Wien filter is configured to correct chromatic aberration in the primary beam. The system also includes a detector assembly configured to detect electrons emanating from the surface of the sample.

Charged Particle Beam Device
20170271121 · 2017-09-21 ·

A processing apparatus and a processing method are provided, which use a charged particle beam device that achieves defection of secondary electrons/reflected electrons at a large angle and cancels out noises of an electromagnetic deflector and an electrostatic deflector to suppress a position shift of a primary electron beam caused by circuit noises of a primary beam/secondary beam separation circuit. In the charged particle beam device that includes an electronic optical system radiating a concentrated electron beam onto a sample placed on a stage to perform scanning and captures an image of the sample, a reference signal and a signal generation unit of a voltage-source control signal applied to the electrostatic deflector generating the electrostatic deflector and a reference signal and a signal generation unit of a current-source control signal applied to the electromagnetic deflector generating a magnetic field are made common in an overlapping-electromagnetic-deflector control unit that controls a path of the secondary electrons/reflected electrons incident on a detector, and frequency characteristics and phase characteristics of the voltage control signal are coincident with those of the current-source control signal.