Energy dependent sensitivity of Au-coated-microchannel plate detector in X-ray range

A kind of photodetector was developed by microchannel plate (MCP) evaporated with Au photocathode. According to the resistive and capacitive characteristics of MCP, a method for measuring the energy dependent sensitivity was established. The response of the detector for incident energy from 2.1 to 6.0 keV was calibrated on the 3B3 medium energy X-ray beamline. An AXUV-100 silicon diode, which was produced by IRD Company and absolutely calibrated by NIST, was used as the secondary standard detector to calibrate two Au-coated-MCP detectors with 25 and 100 nm thick Au films, respectively. The experimental result, shows that, the elements’ absorption line and the thickness of Au film are very important to the quantum efficiency, and the sensitivity of the detector with 100 nm thick Au film is