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SUMMARY A microchannel plate detector has advantages over conventional Everhart‐Thornley detectors for low voltage SEM applications. A microchannel plate can provide symmetric SEM signal detection at the low beam energies needed for non‐destructive examination of integrated circuits. Microchannel plate detectors are effective for both secondary electron and backscattered electron imaging. Their relatively small size and ability to be mounted directly below the final pole piece give them improved performance relative to conventional detectors in applications requiring short working distances. A significant amount of laboratory and applications experience has shown that microchannel plates are reliable and sufficiently resistant to contamination for use in high volume, production environments which require low voltage SEM imaging.

Micro-diffraction based crystallography is essential to the design and development of many classes of ‘crafted materials’. Although the scanning electron microscope can provide crystallographic information with high spatial resolution, its current utility is severely limited by the low sensitivity of existing diffraction techniques (ref: Dingley). Previously, Joy showed that energy filtering increased contrast and pattern visibility in electron channelling. This present paper discribes the effect of energy filtering on EBSP sensitivity and backscattered SEM imaging.The EBSP detector consisted of an electron energy filter, a microchannel plate detector, a phosphor screen, optical coupler, and a slow scan CCD camera. The electrostatic energy filter used in this experiment was constructed as a cone with 5 coaxial electrodes. The angular field-of-view of the filter was approximately 38°. The microchannel plate, which was the initial sensing component, had high gain and had 50% to 80% detection efficiency for the low energy electrons that passed through the retarding field filter.

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