论文信息 - Negative electron affinity and electron emission at cesiated GaN and AlN surfaces

Negative electron affinity and electron emission at cesiated GaN and AlN surfaces

Abstract The electronic structure of GaN and AlN (0001) surfaces and modification by cesium (Cs) adsorption are investigated via ultra-violet and X-ray photoemission spectroscopy (UPS, XPS) and total yield spectroscopy. The electron affinity (EA) of the clean and ordered 1×1 surfaces is found to be equal to 3.3 and 1.9 eV for GaN and AlN, respectively. Cs adsorption (with the help of oxygen pre-treatment in the case of GaN) reduces EA on both surfaces by about 2.6–2.8 eV, leading to true negative electron affinity (NEA) in the case of AlN and effective NEA in the case of GaN. Total yield spectroscopy confirms NEA on both surfaces.

Chih-I Wu | Antoine Kahn | A. Kahn | Chih‐I Wu

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