High-performance microchannel plates based on atomic layer deposition for the preparation of functional layers
Zhuoxi Lian, Dan Wang, Xiangping Zhu, Yong Ning He
Abstract
Abstract Microchannel plates (MCPs) are critical devices used in electron multiplication for applications such as night vision, mass spectrometry, and particle detection. Traditional MCP fabrication using lead silicate glass faces challenges in meeting the increasing demands for high gain, long lifespan, and low noise. In this study, pursuing MCP with excellent performance, atomic layer deposition (ALD) technology was employed to prepare Ru/Al 2 O 3 composite film and Al 2 O 3 film as the conductive layer and secondary electron emission (SEE) layer respectively in microchannels. By optimizing the ALD cycle ratio of Ru and Al 2 O 3 , process parameters that satisfy the MCP bulk resistance requirements were obtained. As the number of ALD cycles for Ru increases, the bulk resistance decreases, enabling the regulation of bulk resistance within the range of tens to hundreds of megaohms. The variation of the secondary electron yield of Al 2 O 3 film with increasing thickness was investigated, and a preferable thickness of 5–7 nm was obtained. When the ALD cycle ratio of Ru to Al 2 O 3 in the conductive layer is 29:10 and the thickness of the Al 2 O 3 film in the SEE layer is 7 nm, the gain of the fabricated MCP exceeds 3 × 10 5 at a bias voltage of 1500 V. As well as the fabricated MCP also exhibits excellent uniformity and stability in electron multiplication. Additionally, a GaAs image intensifier utilizing the prepared MCP exhibited superior performance in field-of-view uniformity, low-light imaging, and resolution. This study makes significant engineering sense for enhancing MCP performance and expanding its applications in imaging and related fields.