Electronic properties of the GaN nanowires surface activated by Cs/Li/NF3/Cs/Li alternate method in a high-concentration residual gas environment

Abstract

Listen

Translate article

The characteristics of models that adsorb different concentrations of H2O and CO2 residual gases on the surface of GaN nanowires activated alternately by Cs/Li/NF3/Cs/Li investigated systematically using first-principles, including adsorption energy, atomic structure, and work function, electron affinity and dipole moment. For the Cs/Li/NF3/Cs/Li alternately activated surface, H2O molecules are more likely to remain on the surface than CO2 molecules. In a high-concentration residual gas atmosphere, Cs/Li/NF3/Cs/Li alternately activated surface can be more stable than pure p-type surfaces. However, high concentrations of H2O and CO2 gas have a destructive effect on the activation layer, and it can even make the activated surface lose its negative electron affinity. The newly generated dipole moment from Cs and Li atoms to residual gas molecules greatly affects the normal operation of the cathode activation layer. From the analysis of characteristic data such as charge distribution and work function, the alternately activated cathode needs to work in a high vacuum state as much as possible to avoid generating a high-concentration residual gas environment.