Nitridation of Al(111) surface induced by N translational energy; Surface temperature dependence

Nの並進運動エネルギーによって誘起されるAl(111)表面の窒化; 表面温度依存性

寺岡 有殿; 神農 宗徹*; 高岡 毅*; Harries, J.; 岡田 隆太; 岩井 優太郎*; 吉越 章隆 ; 米田 忠弘*

Teraoka, Yuden; Jinno, Muneaki*; Takaoka, Tsuyoshi*; Harries, J.; Okada, Ryuta; Iwai, Yutaro*; Yoshigoe, Akitaka; Komeda, Tadahiro*

The Al(111) surface has been directly nitrided using the supersonic N molecular beam of 2.0 eV at a sample temperature region below 773 K. The nitrogen uptake curves obtained showed an incubation time at the reaction temperature below 473 K, indicating the formation of nitrided local structures (precursors) at the surface. Actually, nitrogen diffusion into aluminium bulk even at 473 K had been already confirmed by a depth profile analysis using angle-resolved photoemission spectroscopy. The Al2p photoemission spectra showed shoulder structures only slightly shifted to higher binding energies, suggesting that sub-nitride components are predominant in the nitride layer. Peak deconvolution of N1s photoemission spectra reveals that the three-coordinated nitrogen (N) dominates among the four chemical state components (N : n=1-4) although four-coordinated nitrogen (N) shares in both Wurtzite and Zinc-Blende type crystal structures.