In one embodiment, a method includes generating a model trained to predict a low-probability stochastic defect, calibrating, using unbiased measurement data, the model to a specific lithography process, patterning process, or both to generate a calibrated model, using the calibrated model to predict the low-probability stochastic defect; and modifying, based on the low-probability stochastic defect, a variable, parameter, setting, or some combination of a manufacturing process of a device.

A charged particle assessment tool including: an objective lens configured to project a plurality of charged particle beams onto a sample, the objective lens having a sample-facing surface defining a plurality of beam apertures through which respective ones of the charged particle beams are emitted toward the sample; and a plurality of capture electrodes, each capture electrode adjacent a respective one of the beam apertures, configured to capture charged particles emitted from the sample.

A charged particle beam device 1 includes: a plurality of detectors 7 for detecting a signal particle 9 emitted from a sample 8 irradiated with a charged particle beam 3 and converting the detected signal particle 9 into an output electrical signal 17; an energy discriminator 14 provided for each detector 7 and configured to discriminate the output electrical signal 17 according to energy of the signal particle 9; a discrimination control block 21 for setting an energy discrimination condition of each of the energy discriminators 14; and an image calculation block 22 for generating an image based on the discriminated electrical signal. The discrimination control block 21 sets energy discrimination conditions different from each other among the plurality of energy discriminators 14.

A wafer inspection system is disclosed. According to certain embodiments, the system includes an electron detector that includes circuitry to detect secondary electrons or backscattered electrons (SE/BSE) emitted from a wafer. The electron beam system also includes a current detector that includes circuitry to detect an electron-beam-induced current (EBIC) from the wafer. The electron beam system further includes a controller having one or more processors and a memory, the controller including circuitry to: acquire data regarding the SE/BSE; acquire data regarding the EBIC; and determine structural information of the wafer based on an evaluation of the SE/BSE data and the EBIC data.

From a reference waveform 112 and a BSE signal waveform 211 that is extracted from a backscattered electron image and indicates a backscattered electron signal intensity from a pattern along a first direction, a difference waveform indicating a relationship between the backscattered electron signal intensity and a difference between a coordinate of the BSE signal waveform and a coordinate of the reference waveform which have the same backscattered electron signal intensity is generated, and presence or absence of a shielded region 203 that is not irradiated with a primary electron beam on a side wall of the pattern is determined based on the difference waveform. The reference waveform indicates a backscattered electron signal intensity from a reference pattern along the first direction in which the side wall is formed perpendicularly to an upper surface and a bottom surface of the pattern when the reference pattern is scanned with the primary electron beam.

A charged particle beam apparatus with a charged particle source to generate a primary charged particle beam, a sample holder to hold a sample for impingement of the primary charged particle beam on the sample, a pulsed laser configured to generate a pulsed light beam for impingement onto an area on the sample, and an electrode to collect electrons emitted from the sample in a non-linear photoemission.

Roughness measurement corrects a machine difference utilizing first PSD data indicating power spectral density of a line pattern measured for a line pattern formed on a wafer for machine difference management by a reference machine in roughness index calculation and second PSD data indicating power spectral density of a line pattern measured for the line pattern formed on the wafer for machine difference management by a correction target machine are used to obtain a correction method for correcting the power spectral density of the second PSD data to the power spectral density of the first PSD data, power spectral density of a line pattern is measured as third PSD data from a scanning image of the line pattern, and corrected power spectral density obtained by correcting the power spectral density of the third PSD data by the obtained correction method is calculated.

An improved leveling sensor and method for adjusting a sample height in a charged-particle beam inspection system are disclosed. An improved leveling sensor comprises a light source configured to project a first pattern onto a sample and a detector configured to capture an image of a projected pattern after the first pattern is projected on the sample. The first pattern can comprise an irregularity to enable a determination of a vertical displacement of the sample.

An improved charged particle beam inspection apparatus, and more particularly, a particle beam inspection apparatus including an improved alignment mechanism is disclosed. An improved charged particle beam inspection apparatus may include a second electron detection device to generate one or more images of one or more beam spots of the plurality of secondary electron beams during the alignment mode. The beam spot image may be used to determine the alignment characteristics of one or more of the plurality of secondary electron beams and adjust a configuration of a secondary electron projection system.

A charged particle beam scanning module, a charged particle beam device, and a computer that can correct an INL error in a DAC circuit in real time. The charged particle beam scanning module includes a scanning controller configured to output a scanning digital signal of a charged particle beam, a DAC circuit configured to convert the scanning digital signal into a scanning analog signal and output the scanning analog signal, and an ADC circuit configured to convert the scanning analog signal into an evaluation digital signal. A sampling frequency at which the DAC circuit samples the scanning digital signal is a first frequency, and a sampling frequency at which the ADC circuit samples the scanning analog signal is a second frequency smaller than the first frequency. The scanning controller determines an output characteristic of the DAC circuit by evaluating the scanning digital signal and the evaluation digital signal.