Chemical Composition, Structure, and Functional Properties of the Coatings of Microchannel Plate Channels

Abstract

To provide the necessary electrical conductivity of microchannel plates, it is proposed that a thin RuO_x film be used by means of its pulsed metalorganic chemical vapor deposition onto the walls of the channels. The chemical composition, structure, electrical conductivity, and secondary electron emission are studied using satellite samples. The RuO_x film is shown to have a globular structure with a characteristic size of ~100 nm. The core of each globule (average size, ~21 nm) represents a mixture of the Ru and RuO₂ phases with a ratio of nearly 4 : 6. The other part of the globule is amorphous with a Ru : RuO₂ ratio of ~5.4 : 4.6. The electrical conductivity of the films has a metallic character. The secondary-electron-emission coefficient of RuO_x increases from 2.5 to ~4 after annealing in air at temperatures up to 800°C.