ceramics and other materials, and methods of creation of conductive and secondary emissive layers, are proposed. But despite abundance of publications, new MCP technology, able to replace the conventional one, is still not created.
Anodic aluminum oxide
Fig. 1. Natural pores of anodic aluminum oxide. View from above.
We propose new material for MCP production: anodic aluminum oxide. It is being formed by electrochemical oxidation of aluminum in electrolytes, weakly dissolving alumina and consists of regular hexagonally packed cells, which are parallel to each other and perpendicular to the surface of aluminum substrate (fig. 1 and 2).
Fig. 2. Anodic aluminum oxide. Side view.
Each cell has axial pore, closed by the barrier oxide layer on the side of aluminum anode (fig. 3). The cell diameter is mainly defined by the anodization voltage. Cell diameter rating is about 2.5 – 3.0 nm per volt of anodizing voltage.
Fig.3. Barrier layer of anodic aluminum oxide
Diameter of the pore depends on the electrolyte nature, its temperature and concentration, the current density and other parameters of anodization process. It is possible to vary the diameters of the cell and the pore by variation of the electrolyte composition and anodization conditions. The pore diameter can also be enlarged by