Contribution of microchannel plate luminescence to the noise of 20-inch photomultiplier tubes

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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Low - Voltage Scanning Electron Microscopy Imaging, Secondary and Backscatter, With Microchannel Plate Detector

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180963 ◽

1990 ◽

Vol 48 (1) ◽

pp. 442-442

Author(s):

Galen Powers ◽

Ray Cochran

Keyword(s):

Low Voltage ◽

Beam Current ◽

Microchannel Plate ◽

Normal Operation ◽

Microscopy Imaging ◽

Backscatter Signal ◽

Vacuum Interface ◽

Width Measurements ◽

Working Distance ◽

Beam Currents

The capability to obtain symmetrical images at voltages as low as 200 eV and beam currents less than 9 pico amps is believed to be advantageous for metrology and study of dielectric or biological samples. Symmetrical images should allow more precise and accurate line width measurements than currently achievable by traditional secondary electron detectors. The low voltage and current capability should allow imaging of samples which traditionally have been difficult because of charging or electron beam damage.The detector system consists of a lens mounted dual anode MicroChannel Plate (MCP) detector, vacuum interface, power supplies, and signal conditioning to interface directly to the video card of the SEM. The detector has been miniaturized so that it does not interfere with normal operation of the SEM sample handling and alternate detector operation. Biasing of the detector collection face will either add secondaries to the backscatter signal or reject secondaries yielding only a backscatter image. The dual anode design allows A−B signal processing to provide topological information as well as symmetrical A+B images.Photomicrographs will show some of the system capabilities. Resolution will be documented with gold on carbon. Variation of voltage, beam current, and working distance on dielectric samples such as glass and photoresist will demonstrate effects of common parameter changes.

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Simulation on temporal and spatial characteristics for the non-gain microchannel plate

JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING ◽

10.3724/sp.j.1249.2018.05500 ◽

2018 ◽

Vol 35 (5) ◽

pp. 500

Author(s):

Ke ZHANG ◽

Houzhi CAI ◽

Jinyuan LIU

Keyword(s):

Microchannel Plate ◽

Spatial Characteristics ◽

Temporal And Spatial ◽

Temporal And Spatial Characteristics

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