Study Of The Uniform Surface Electron Source And The Channeltron Electron Multiplier

During the production process of the microchannel plate(MCP),a large amount of gas is adsorbed on the inner surface of the microchannel.These gases cause the life of the MCP to be shortened,the noise is increased,and the sensitivity is lowered.In order to meet the performance test and electronic scrubbing of large-size microchannel plates(MCP),an electron gun is designed to produce a surface electron source with large size,uniformity and wide dynamic range.The electron gun adopts tantalum wire with a lower work function,and the coiled structure is processed.By applying an electric field,the electron source beam density emitted to the microchannel plate is adjustable,and the uniformity is better than 10%.For electronic scrubbing,stability is better than±0.1?A within 12 hours,dynamic range is up t.o 7 orders of magnitude(10-12?10-5A).After a large number of experimental tests,the electron gun can meet the requirements of the micro-channel board electronic scrubbing process and DC performance test.The channel electron multiplier(CEM)can directly detect energetic particles such as electrons,ions,and X-rays,and is an important component of precision instruments such as analytical instruments and detection instruments.In order to properly use and develop high-performance CEM,it is necessary to set up a test platform to conduct comprehensive test research on the performance of CEM.In this paper,first,test the resistance of CEM under different voltages;then,test the gain of different voltages and input currents of CEM;finally,test the single photoelectron charge spectrum at different voltages of CEM.The test results show that with the increase of CEM voltage,the resistance is stable at 99MQ;the CEM DC gain reaches the order of 106,and the gain decreases with the increase of input current;the pulse gain reaches the order of 108,the voltage The FWHM is 46.9%at 2700V.As the CEM voltage increases,the gain gradually increases and the FWMH gradually decreases.Through the test research,the test platform designed in this paper has achieved the purpose of evaluating CEM performance.