This contribution focuses on the fabrication and characterization of microchannel plates made of hydrogenated amorphous silicon (AMCPs). Flexible fabrication processes and the semi-conducting nature of amorphous silicon could give these detectors the advantage of superior temporal and spatial resolution over conventional lead glass based microchannel plates (MCPs). The current work focuses on the fabrication and characterization of high aspect ratio devices. The multiplication gain was measured under continuous illumination of UV light using a customized setup. Through optimization of the microengineering processes, devices with high aspect ratios up to 25 were realized which resulted in a multiplication factor of ~1500 for this new generation of AMCPs. This high gain, coupled with the AMCPs remarkable temporal and spatial resolution make them a promising alternative for various applications such as detectors for positron emission tomography.