Abstract: One embodiment disclosed relates to a method for accurate electron beam metrology. A substrate with a target feature is loaded into a scanning electron microscope. An electron beam is scanned over the target feature, and scattered electrons are detected therefrom. A characteristic of the target feature is measured by finding optimal values for parameters of a mathematical model which accounts for substrate charging effects. Principal component analysis may be used to advantageously result in reduced requirements for processing time and/or computational speed.

Abstract: One embodiment disclosed relates to a method for robustly detecting a defective high aspect ratio (HAR) feature. A surface area of a semiconductor specimen with HAR features thereon is charged up, and a primary beam is impinged onto the surface area. Scattered electrons that are generated due to the impingement of the primary beam are extracted from the surface area. An energy filter is applied to remove the scattered electrons with lower energies, and the filtered electrons are detected. Image data is generated from the detected electrons, and an intensity threshold is applied to the image data.

Abstract: One embodiment disclosed relates to an apparatus for inspecting a substrate using charged particles. The apparatus includes an illumination subsystem, an objective subsystem, a projection subsystem, and a beam separator interconnecting those subsystems. Advantageously, the illumination subsystem includes a tilt deflector configured to controllably tilt the incident beam. The tilt of the incident beam caused by the tilt deflector is magnified prior to the incident beam impinging onto the substrate. This technique allows for achieving large beam tilts at the substrate without lens aberrations caused by introducing tilt at the objective lens and without complications due to using a tiltable stage. Other embodiments are also disclosed.

Abstract: The disclosure relates to filtered e-beam inspection and review. One embodiment pertains to the filtered inspection or review of a specimen with a high aspect ratio feature. Advantageously, the energy and/or angular filtering improves the information retrievable relating to the high aspect ratio feature on the specimen. Another embodiment pertains to a method for energy-filtered electron beam inspection where a band-pass energy filtered image data is generated by determining the difference between a first high-pass energy-filtered image data set and a second high-pass energy-filtered image data set.

Abstract: The disclosure relates to a method and system of electron beam scanning for measurement, inspection or review. In accordance with one embodiment, the method includes a first scan on a region to collect first image data. The first image data is processed to determine information about a feature in the region. A scanning method is selected for imaging the feature. A second scan using the selected scanning method on the feature is then applied to collect second image data.

Abstract: The disclosure relates to filtered e-beam inspection and review. One embodiment pertains to the filtered inspection or review of a specimen with a high aspect ratio feature. Advantageously, the energy and/or angular filtering improves the information retrievable relating to the high aspect ratio feature on the specimen. Another embodiment pertains to a method for energy-filtered electron beam inspection where a band-pass energy filtered image data is generated by determining the difference between a first high-pass energy-filtered image data set and a second high-pass energy-filtered image data set.

Abstract: The disclosure relates to measuring an undercut of a feature on a specimen using a scanning electron microscope (SEM). In accordance with one embodiment, a method for measuring the undercut includes illuminating the feature with a primary electron beam at an incident angle, changing the incident angle of the primary electron beam over a set of angles, measuring an intensity of scattered electrons from the feature for each incident angle in the set of angles, and determining a discontinuity in the intensities as a function of the incident angle.

Abstract: The disclosure relates to measuring an undercut of a feature on a specimen using a scanning electron microscope (SEM). In accordance with one embodiment, a method for measuring the undercut includes illuminating the feature with a primary electron beam at an incident angle, changing the incident angle of the primary electron beam over a set of angles, measuring an intensity of scattered electrons from the feature for each incident angle in the set of angles, and determining a discontinuity in the intensities as a function of the incident angle.