Patent classifications
H01J2237/1536
System and method for learning-guided electron microscopy
A system and method is provided for rapidly collecting high quality images of a specimen through controlling a re-focusable beam of an electron microscope. An intelligent acquisition system instructs the electron microscope to perform an initial low-resolution scan of a sample. A low-resolution image of the sample is received by the intelligent acquisition system as scanned image information from the electron microscope. The intelligent acquisition system then determines regions of interest within the low-resolution image and instructs the electron microscope to perform a high-resolution scan of the sample, only in areas of the sample corresponding to the determined regions of interest or portions of the determined regions of interest, so that other regions within the sample are not scanned at high-resolution, where the high-resolution scanning in the regions of interest is guided by a probability map using a deep neural network for segmentation.
APPARATUS OF PLURAL CHARGED-PARTICLE BEAMS
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.
Apparatus of plural charged-particle beams
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.
MULTI-BEAM DIGITAL SCAN AND IMAGE ACQUISITION
A multi-beam charged particle microscope and a method of operating a multi-beam charged particle microscope for wafer inspection with high throughput and with high resolution and high reliability are provided. The method of operation and the multi-beam charged particle beam microscope comprises a mechanism for a synchronized scanning operation and image acquisition by a plurality of charged particle beamlets according a selected scan program, wherein the selected scan program can be selected according an inspection task from different scan programs.
CHARGED PARTICLE ASSESSMENT TOOL, INSPECTION METHOD
A charged-particle tool including: a condenser lens array configured to separate a beam of charged particles into a first plurality of sub-beams along a respective beam path and to focus each of the sub-beams to a respective intermediate focus; an array of objective lenses, each objective lens configured to project one of the plurality of sub-beams onto a sample; a corrector including an array of elongate electrodes, the elongate electrodes extending substantially perpendicular to the beam paths of the first plurality of sub-beams and arranged such that a second plurality of the sub-beams propagate between a pair of the elongate electrodes, the second plurality of sub-beams being a subset of the first plurality of sub-beams; and an electric power supply configured to apply a potential difference between the pair of elongate electrodes so as to deflect the second plurality of sub-beams by a desired amount.
Charged Particle Beam Device and Inspection Method
Provided is a charged particle beam device for which deterioration in throughput in the event of abnormality of multiple beams can be prevented. The charged particle beam device includes: a stage 11 on which a sample is mounted; a charged particle optical system configured to irradiate the sample with multiple beams including multiple primary beams; a detector 15 configured to detect secondary beams generated by interactions between the primary beams and the sample and output detection signals; and a control unit 17 configured to control the stage and the charged particle optical system to generate image data based on the detection signals from the detector obtained by scanning the sample with the multiple beams using a first scanning method. The control unit changes, when the abnormality of the multiple beams is detected based on the image data, the multiple beams to scan the sample using a second scanning method, and a scanning width of the multiple beams for scanning the sample is greater in the second scanning method than in the first scanning method.
SCANNING ELECTRON MICROSCOPE
The present invention relates to a scanning electron microscope configured to scan a workpiece, such as a wafer, mask, panel, or substrate, with an electron beam to generate an image of the workpiece. The scanning electron microscope includes a deflector (17, 18) configured to deflect the electron beam to scan a target region (T) on the workpiece (W) with the electron beam, and a deflection controller (22) configured to apply to the deflectors (17, 18) a scanning voltage that causes the electron beam to scan the target region (T) and an offset voltage that shifts the electron beam from an optical axial center (O) to the target region (T).
Method for calibrating a scanning charged particle microscope
A method for calibrating a scanning charged particle microscope, such as a scanning electron microscope (SEM), is provided. The method includes dividing a wafer into a plurality of regions; preparing, on each of the plurality of regions, a pattern including a first periodic structure interleaved with a second periodic structure, the first and second periodic structures having an induced offset; determining an actual pitch the first and second periodic structures and thereby determining actual induced offset on each of the plurality of regions; selecting a plurality of regions from among the plurality of regions; measuring, by the SEM, a pitch of first and second periodic structures on each of the plurality of regions; and performing linearity calibration on the SEM based on the determining and the measuring.
Sample Display Method
A sample display method by means of a scanning electron microscope comprises at most one active objective lens located above a first scanning element and a second scanning element. A primary electron beam is deflected so as to be focused by an objective lens so that the beam propagates from the second scanning element towards a sample approximately parallel to the SEM optical axis, wherein the sample is also tilted relative to the SEM optical axis by an angle other than 90°, or it is a sample with distinct topography.
Charged particle beam apparatus
An object of the invention is to correct an aberration or a defocus of an electron beam for irradiation, and control an influence on a deflector by a fluctuation in an electric field of an electrostatic lens. The invention provides a charged particle beam apparatus including a deflector that deflects a charged particle beam with which a specimen is irradiated, an objective lens that focuses the charged particle beam on the specimen, an electrostatic lens that includes a part of the objective lens and to which a voltage for correcting the aberration or the defocus of the charged particle beam is applied, and an constant electric field applying electrode that is provided between the deflector and the electrostatic lens and to which a constant voltage having a same sign with the voltage applied to the electrostatic lens is applied.