Performance testing and simulation of microchannel plates for CALO-IsCMOS

Objective Microchannel plate (MCP) serves as the core electron multiplication devices in the intensified scientific complementary metal-oxide-semiconductor (IsCMOS) of the high energy radiation detection facility (HERD). This study develops high gain, long lifetime, large open area, low halo MCP using atomic layer deposition (ALD) and flaring technology to meet the stringent requirements of space exploration.MethodsThe surface morphology and microstructure of the MCP are characterized through scanning electron microscopy (SEM), X-ray photoelectron spectrometer (XPS), atomic force microscopy (AFM) and three-dimensional profilometer. Electron multiplication and imaging characteristics are evaluated through gain, lifetime, and imaging tests. A simulation model was constructed using CST Studio Suite to validate the effects of secondary electron emission (SEE) and open area ratio (OAR) on MCP performance.Results and DiscussionsTest results demonstrate that ALD technique forms a uniform and dense Al2O3 film on the MCP channel wall, reducing surface roughness from 0.55 nm to 0.43 nm, resulting in a 71% reduction in the amount of deformation and increasing gain from 372@800 V to 743@800 V. The lifetime improves by 6.5 times at a total output charge of 30 C. The flaring technology enhances the OAR from 67% to 87%, and increases the gain from743@800 V to 945@800 V. Concurrently, this process reduces the full width of 10% maximum (FWM) of the halo diameter from 378 μm to 288 μm. The simulation results indicate that higher SEE and OAR are effectively enhancing the MCP gain and suppressing electron scattering along with the halo effects.ConclusionsThe test results are in good agreement with the simulation results, providing a significant experimental and theoretical basis for high-performance MCP used in space exploration.