Measurement of total electron emission yield of insulators based on self-terminating charge neutralization

For insulators, the accumulated charge on the surface after electron bombardment will interfere with the total electron emission yield (TEEY) measurement. This work develops a novel method to automatically measure the TEEY of insulators based on self-terminating charge neutralization using two neutralization electron guns. We perform theoretical analysis and experimental design for the neutralization of positive and negative charges. Positive charges are neutralized by an electron gun whose cathode is equipotential to the sample. Negative charges are neutralized by another electron gun whose cathode is adjusted to a negative potential with respect to the grounded sample, which is set between E_P1/e and E_P2/e. We test the control and stability performance of the TEEY measurement system based on the timing design of the electron gun switching and believe that it meets the TEEY measurement requirements. The TEEY measurements of glass, Si, and SiO₂ are in good agreement with the data reported in the references, which validates the accuracy of our method in this work. We anticipate that our method provides an essential reference for the rapid TEEY measurements of insulators.