We report a cost-effective and production achievable path to fabricate robust large-area microchannel plates
(MCPs), which offers the new prospect for larger area MCP-based detector technologies. We used atomic Layer
Deposition (ALD), a thin film growth technique, to independently adjust the desired electrical resistance and secondary
electron emission (SEE) properties of low cost borosilicate glass micro-capillary arrays (MCAs). These capabilities
allow a separation of the substrate material properties from the signal amplification properties. This methodology enables
the functionalization of microporous, highly insulating MCA substrates to produce sturdy, large format MCPs with
unique properties such as high gain (<107/MCP pair), low background noise, ~10ps time resolution, sub-micron spatial
resolution and excellent stability after only a short (2-3days) scrubbing time.
The ALD self-limiting growth mechanism allows atomic level control over the thickness and composition of
resistive and secondary electron emission (SEE) layers that can be deposited conformally on high aspect ratio (~100)
capillary glass arrays. We have developed several robust and consistent production doable ALD processes for the
resistive coatings and SEE layers to give us precise control over the MCP parameters. Further, the adjustment of MCPs
resistance by tailoring the ALD material composition permits the use of these MCPs at high or low temperature detector
applications. Here we discuss ALD method for MCP functionalization and a variety of MCP testing results.
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