Abstract: An electron beam apparatus is configured for dark field imaging of a substrate surface. Dark field is defined as an operational mode where the image contrast is sensitive to topographical features on the surface. A source generates a primary electron beam, and scan deflectors are configured to deflect the primary electron beam so as to scan the primary electron beam over the substrate surface whereby secondary and/or backscattered electrons are emitted from the substrate surface, said emitted electrons forming a scattered electron beam. A beam separator is configured to separate the scattered electron beam from the primary electron beam. The apparatus includes a cooperative arrangement which includes at least a ring-like element, a first grid, and a second grid. The ring-like element and the first and second grids each comprises conductive material. A segmented detector assembly is positioned to receive the scattered electron beam after the scattered electron beam passes through the cooperative arrangement.

Abstract: A method of measuring properties of a sample using an electron beam. Coordinates of a measurement site on the sample, and a diameter of the electron beam are defined. Multiple measurement locations are determined within the measurement site, using the coordinates of the measurement site and the diameter of the electron beam. The measurement locations are selected such that the electron beam when directed at the multiple measurement locations (either through beam deflection or sample movement) substantially covers the measurement site. The electron beam is directed to the measurement locations and properties of the sample are measured at each of the measurement locations.

Abstract: An apparatus for detecting properties of a sample. An electron beam generator produces an electron beam and directs the electron beam at a desired point on the sample. The sample thereby emits characteristic x-rays at takeoff angles. A collimator receives and parallelizes the x-rays and converts the takeoff angles of the x-rays to positional differences between the parallelized x-rays. A diffractor receives and deflects the x-rays. A position sensitive detector receives the deflected x-rays and detects the positional differences between the x-rays, and generates signals that are characteristic of the received x-rays. An analyzer receives the signals from the detector and determines the properties of the sample based at least in part on the positional differences between the x-rays.