Abstract: A mega-boule is used in fabricating microchannel plates (MCPs). The mega-boule has a cross-sectional surface including an island section, an inner perimeter section and an outer perimeter section, each section occupying a distinct portion of the cross-sectional surface. The island section is formed of a first plurality of optical fibers, transversely oriented to the cross-sectional surface, each optical fiber including a cladding formed of non-etchable material and a core formed of etchable material. The inner perimeter section is formed of non-etchable material and is disposed to surround the island section. The outer perimeter section is formed of a second plurality of optical fibers, transversely oriented to the cross-sectional surface, each optical fiber including a cladding formed of non-etchable material and a core formed of etchable material, and the outer perimeter section is disposed to surround the island section and the inner perimeter section.