Secondary Electron Emission from Charged Dielectrics*

Secondary electron emission (SEE) from dielectric materials is relevant to a number of plasma applications such as Hall thrusters, surface discharges, plasma processing etc. Measurement of SEE properties from non-conductive and poorly conductive materials is usually performed in, at least, high vacuum environments using pulsed electron guns. Selecting pulse duration and current minimizes undesired surface charging effects on SEE measurements; however, dielectric surface charging is unavoidable in these measurements [1]. Thus, it is important to study charging effects on the accuracy of SEE measurements. In this work, we investigate these effects for SEE from ceramic materials (e.g. Al₂O₃, boron nitride) used in the above plasma applications, and explore discharging techniques such as substrate heating and others [2]. 

[1] A. Dunaevsky, Y. Raitses, and N. J. Fisch, Phys. Plasmas 10, 2574 (2003); 

[2] M Belhaj, T Tondu, V Inguimbert, and J P Chardon, Phys. D: Appl. Phys. 42, 105309 (2009)].