Monte-Carlo Simulations on the Noise Characteristics of the Ion Barrier Film of Microchannel Plate

In the third-generation Low-light-level (LLL) image tube, a super thinner Ion barrier film (IBF) is often coved on the input surface of Microchannel plate (MCP) to protect the photocathode and prolong the operation life of the image tube. In order to further investigate on the properties of IBFs, a physical model for the interaction of low-energy electrons with solid was described. A Monte-Carlo simulation on the noise characteristics of the Al₂O₃ IBF was conducted. Trajectory and spatial distribution of the transmission electrons were simulated with Matlab software. Besides, influence factors for transmittance characteristic of electrons in the Al₂O₃ IBF were studied. Finally, noise factor of IBFs was calculated and discussed, based on a method of Time domain division. This work provided a theory support for fabricating high performance LLL device.