Anomalous hexagonal superstructure of aluminum oxide layer grown on NiAl(110) surface

作者：Krukowski Pawel; Chaunchaiyakul Songpol; Minagawa Yuto; Yajima Nami; Akai Kasaya Megumi; Saito Akira; Kuwahara Yuji

来源：Nanotechnology, 2016, 27(45): 455708.

DOI：10.1088/0957-4484/27/45/455708

• aluminum oxide
• NiAl(110)
• superstructure
• STM

A modified method for the fabrication of a highly crystallized layer of aluminum oxide on a NiAl(110) surface is reported. The fabrication method involves the multistep selective oxidation of aluminum atoms on a NiAl(110) surface resulting from successive oxygen deposition and annealing. The surface morphology and local electronic structure of the novel aluminum oxide layer were investigated by high-resolution imaging using scanning tunneling microscopy (STM) and current imaging tunneling spectroscopy. In contrast to the standard fabrication method of aluminum oxide on a NiAl(110) surface, the proposed method produces an atomically flat surface exhibiting a hexagonal superstructure. The superstructure exhibits a slightly distorted hexagonal array of close-packed bright protrusions with a periodicity of 4.5 +/- 0.2 nm.
Atomically resolved STM imaging of the aluminum oxide layer reveals a hexagonal arrangement of dark contrast spots with a periodicity of 0.27 +/- 0.02 nm. On the basis of the atomic structure of the fabricated layer, the formation of alpha-Al2O3(0001) on the NiAl(110) surface is suggested.

• 出版日期2016-11-11