Low interface resistance and excellent anti-oxidation of Al/Cu/Ni multilayer thin-film electrodes for Bi 2Te 3-based modules

摘要

AbstractExploring high-performance multilayer electrodes is very important to improve the conversion efficiency of Bi2Te3-based modules. Here, an Al/Cu/Ni multilayer thin-film electrode with low interface resistance and excellent anti-oxidation was designed and fabricated on Bi2Te2.7Se0.3(BTS) legs through vacuum evaporation method. X-ray diffraction, electron probe microanalyzer, field emission scanning electron microscope, X-ray photoelectron spectroscopy and resistance measurements have been employed to investigate the impacts of Ni transition layer (TL) and Al protective layer (PL) on the phase composition, microstructure, interface resistance and anti-oxidation of the electrode. It was found that the Ni TL can significantly lower the interface resistance through improving the lattice match of interface between Cu and BTS. The Cu monolayer and Cu/Ni bilayer thin-film electrodes have very poor anti-oxidation; while the Al/Cu/Ni multilayer thin-film electrode exhibits excellent anti-oxidation because the dense Al2O3layer covering on the surface of the Al PL can effectively prevent from the further oxidation.Graphical abstractDisplay Omitted