STUDY ON QUANTUM EFFICIENCY OF NEA-GaAs WITH VARIOUS THERMAL TREATMENTS; THE INCREASE IN QUANTUM EFFICIENCY BY THE LOW TEMPERATURE TREATMENT

摘要

Evolution of quantum efficiency (QE) is discussed in detail in relation to the history of conditions of negative electron affinity (NEA) activation and thermal pretreatment. An average QE of 0.10 was observed after multiple NEA activation with thermal pretreatment at 550°C, and a high QE of over 0.13 was observed with lower temperature activation (450°C). Our findings indicated that the increase in QE is caused by the number of electron emission sites due to the difference in the formation and desorption rates of Cs-Ga bonds.