Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5424150 | Surface Science | 2010 | 7 Pages |
Structures of monolayer nickel nitride (NiN) on Cu(0Â 0Â 1) surface are studied by X-ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). Formations of Ni-N chemical bonds and NiN monolayer at the surface are confirmed by XPS on the N-adsorbed Cu(0Â 0Â 1) surfaces after Ni deposition and subsequent annealing to 670Â K. A c(2Â ÃÂ 2) structure is always observed in the LEED patterns, which is a quite contrast to the (2Â ÃÂ 2)p4g structure observed usually at the N-adsorbed Ni(0Â 0Â 1) surface. Atomic images by STM indicate the mixture of Ni-N and Cu-N structures at the surface. Density of the trenches on the N-saturated surface decreases and the grid pattern on partially N-covered surfaces becomes disordered with increasing the Ni coverage. These results are attributed to the decrease of the surface compressive stress at the N-adsorbed Cu surface by mixing Ni atoms.