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An exciting new approach for microchannel plate (MCP) detectors could help make them suitable for single photon detection. State-of-the-art clean room technology allows amorphous silicon based microchannel plates (AMCPs) to take a variety of shapes. This versatility together with a new form of on-chip integration enables detector configurations that can be manufactured to meet the exact requirements of the application. The collection efficiency can be increased to 100% while maintaining a maximum gain. With channel lengths of 60 um and diameters below 3 um, the detector gains are now in a range where low level signals can be amplified. In this thesis, we extend the fabrication possibilities of MCP detectors towards structures with diameters in the sub micrometer range, where we expect high gains and excellent timing. We found the minimum channel length of AMCPs with high gain to be 30 um. We show that the timing of such narrow channels is one of the fastest signal amplifications compared to other technologies. Their fast timing together with their high spatial resolution make them a valuable solution for applications where sub millimeter precision is crucial, for example in medical imaging. The results of the thesis alleviate the fabrication process of AMCPs, as the deposition of thick amorphous silicon layers has been identified as the current bottleneck of the fabrication. Through the detailed analysis of secondary emission properties and the implementation in a Monte-Carlo model we can now confidently predict the response of AMCPs with various shapes to a single incident electron. This now provides a quick path to adapt the AMCP configuration directly to the application and makes them a viable alternative to other single photon detectors.
Christophe Ballif, Jonathan Emanuel Thomet, Janina Christine Isabelle Löffler, Samira Alexandra Frey
Christophe Ballif, Quentin Thomas Jeangros, Mathieu Gérard Boccard, Monica Morales Masis, Sihua Zhong, Weiliang Wu