Air-Transfer Production Method for Large-Area Picosecond Photodetectors

We have designed and prototyped the process steps for the batch production of large-area micro-channel-plate photomultipliers (MCP-PMT) using the "air-transfer" assembly process developed with single $LAPPD^{\text{TM}}$ modules. Results are presented addressing the challenges of designing a robust package that can transmit large numbers of electrical signals for pad or strip readout from inside the vacuum tube and hermetically sealing the large-perimeter window-body interface. We have also synthesized a photocathode in a large-area low-aspect-ratio volume, and shown that the micro-channel plates recover their functionality after cathode synthesis. The steps inform a design for a multi-module batch facility employing dual nested low-vacuum (LV) and ultra-high-vacuum (UHV) systems in a small-footprint. The facility design provides full access to multiple MCP-PMT modules prior to hermetic pinch-off for leak-checking and real-time photocathode optimization.