A capacitively coupled segmented polyimide core anode for a microchannel plate timing detector

Abstract

We present a novel readout method for microchannel plate (MCP) signals using timing anodes made from flexible polyimide laminates. Our approach is fully compatible with ultrahigh vacuum environments, as required for the majority of MCP applications. Multiple anode segments and signal tracks are patterned onto the laminate using standard printed circuit board techniques, enabling precise impedance matching of the anode circuit to a 50 Ω coaxial transmission line. Copper patches on both sides of the laminate form embedded capacitors, which are part of integrated decoupling circuits that reduce latency and noise compared to traditional external signal readout methods. The high breakdown voltage of polyimide permits the application of several kilovolts across the anode for MCP detector operation modes that require biasing of both the MCP and the anode. We demonstrate that the MCP signals captured by these segmented polyimide anodes follow a Gaussian profile in time and have a duration <1.5 ns full-width-at-half-maximum. Using an optical detector characterization method, we demonstrate a timing resolution of 40 ps root-mean-square for our ∅50 mm MCPs in Chevron configuration across eight distinct anode segments.