Measurement of True Secondary Electron Emission Yields of Kapton

In order to meet the needs of spacecraft electrification protection and structure design, a test system for true secondary electron emission yield spectrum of space materials has been developed in this paper to test the true secondary electron emission yield(TSEY) of dielectric materials. The test chamber is composed of an injection chamber and an analysis chamber. Each chamber has its vacuum acquisition and detection functions. The internal four-dimensional electronic control test displacement platform, to achieve the adjustment of the sample position; During the test, an electron gun with an energy range of 0 ~ 2000eV was used to generate the electron beam. The true secondary electron emission coefficient of dielectric materials can be measured by pressurizing the Faraday cup and the grid. The true secondary electrons and backscattered electrons are collected and measured by the Faraday cup structure with the grid. The dielectric material was tested by the pulse method. The signal generator controlled the emission time of the electron gun under different energy by generating a pulse signal of 30s. The current signals of the Faraday cup and sample stand were measured by an oscilloscope, respectively. In this paper, the true secondary electron emission coefficient of dielectric materials is measured by using an electron gun to emit low-energy electrons and neutralize the excess charge on the material's surface. The results show that Kapton's true secondary electron emission coefficient can be effectively measured under different electron incident conditions.